Commit Graph

5983 Commits

Author SHA1 Message Date
Li Zefan
75139b8274 cgroups: remove some redundant NULL checks
- In cgroup_clone(), if vfs_mkdir() returns successfully,
  dentry->d_fsdata will be the pointer to the newly created
  cgroup and won't be NULL.

- a cgroup file's dentry->d_fsdata won't be NULL, guaranteed
  by cgroup_add_file().

- When walking through the subsystems of a cgroup_fs (using
  for_each_subsys), cgrp->subsys[ss->subsys_id] won't be NULL,
  guaranteed by cgroup_create().

(Also remove 2 unused variables in cgroup_rmdir().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 08:31:01 -08:00
Robert Richter
d2852b932f Merge branch 'oprofile/ring_buffer' into oprofile/oprofile-for-tip 2009-01-08 14:27:34 +01:00
David Howells
b9456371a7 CRED: Fix commit_creds() on a process that has no mm
Fix commit_creds()'s handling of a process that has no mm (such as one that is
calling or has called daemonize()).  commit_creds() should check to see if
task->mm is not NULL before calling set_dumpable() on it.

Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-01-08 23:13:56 +11:00
Paul Mundt
dd8632a12e NOMMU: Make mmap allocation page trimming behaviour configurable.
NOMMU mmap allocates a piece of memory for an mmap that's rounded up in size to
the nearest power-of-2 number of pages.  Currently it then discards the excess
pages back to the page allocator, making that memory available for use by other
things.  This can, however, cause greater amount of fragmentation.

To counter this, a sysctl is added in order to fine-tune the trimming
behaviour.  The default behaviour remains to trim pages aggressively, while
this can either be disabled completely or set to a higher page-granular
watermark in order to have finer-grained control.

vm region vm_top bits taken from an earlier patch by David Howells.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
2009-01-08 12:04:47 +00:00
David Howells
8feae13110 NOMMU: Make VMAs per MM as for MMU-mode linux
Make VMAs per mm_struct as for MMU-mode linux.  This solves two problems:

 (1) In SYSV SHM where nattch for a segment does not reflect the number of
     shmat's (and forks) done.

 (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
     exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
     that a VMA might be shared and already have its vm_mm assigned to another
     process or a dead process.

A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.

This patch makes the following additional changes:

 (1) Regions are now allocated with alloc_pages() rather than kmalloc() and
     with no recourse to __GFP_COMP, so the pages are not composite.  Instead,
     each page has a reference on it held by the region.  Anything else that is
     interested in such a page will have to get a reference on it to retain it.
     When the pages are released due to unmapping, each page is passed to
     put_page() and will be freed when the page usage count reaches zero.

 (2) Excess pages are trimmed after an allocation as the allocation must be
     made as a power-of-2 quantity of pages.

 (3) VMAs are added to the parent MM's R/B tree and mmap lists.  As an MM may
     end up with overlapping VMAs within the tree, the VMA struct address is
     appended to the sort key.

 (4) Non-anonymous VMAs are now added to the backing inode's prio list.

 (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
     the backing region.  The VMA and region structs will be split if
     necessary.

 (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
     segment instead of all the attachments at that addresss.  Multiple
     shmat()'s return the same address under NOMMU-mode instead of different
     virtual addresses as under MMU-mode.

 (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.

 (8) /proc/maps is now the global list of mapped regions, and may list bits
     that aren't actually mapped anywhere.

 (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
     of RAM currently allocated by mmap to hold mappable regions that can't be
     mapped directly.  These are copies of the backing device or file if not
     anonymous.

These changes make NOMMU mode more similar to MMU mode.  The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2009-01-08 12:04:47 +00:00
Linus Torvalds
8cfc7f9c00 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: fix possible recursive rq->lock
2009-01-07 15:43:58 -08:00
Linus Torvalds
b424e8d3b4 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (98 commits)
  PCI PM: Put PM callbacks in the order of execution
  PCI PM: Run default PM callbacks for all devices using new framework
  PCI PM: Register power state of devices during initialization
  PCI PM: Call pci_fixup_device from legacy routines
  PCI PM: Rearrange code in pci-driver.c
  PCI PM: Avoid touching devices behind bridges in unknown state
  PCI PM: Move pci_has_legacy_pm_support
  PCI PM: Power-manage devices without drivers during suspend-resume
  PCI PM: Add suspend counterpart of pci_reenable_device
  PCI PM: Fix poweroff and restore callbacks
  PCI: Use msleep instead of cpu_relax during ASPM link retraining
  PCI: PCIe portdrv: Add kerneldoc comments to remining core funtions
  PCI: PCIe portdrv: Rearrange code so that related things are together
  PCI: PCIe portdrv: Fix suspend and resume of PCI Express port services
  PCI: PCIe portdrv: Add kerneldoc comments to some core functions
  x86/PCI: Do not use interrupt links for devices using MSI-X
  net: sfc: Use pci_clear_master() to disable bus mastering
  PCI: Add pci_clear_master() as opposite of pci_set_master()
  PCI hotplug: remove redundant test in cpq hotplug
  PCI: pciehp: cleanup register and field definitions
  ...
2009-01-07 15:41:01 -08:00
Linus Torvalds
67acd8b4b7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-async
* git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-async:
  async: don't do the initcall stuff post boot
  bootchart: improve output based on Dave Jones' feedback
  async: make the final inode deletion an asynchronous event
  fastboot: Make libata initialization even more async
  fastboot: make the libata port scan asynchronous
  fastboot: make scsi probes asynchronous
  async: Asynchronous function calls to speed up kernel boot
2009-01-07 15:35:47 -08:00
Paul E. McKenney
c9d557c19f rcu: fix bug in rcutorture system-shutdown code
This patch fixes an rcutorture bug found by Eric Sesterhenn that
resulted in oopses in response to "rmmod rcutorture".  The problem
was in some new code that attempted to handle the case where a system
is shut down while rcutorture is still running, for example, when
rcutorture is built into the kernel so that it cannot be removed.
The fix causes the rcutorture threads to "park" in an
schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT) rather than
trying to get them to terminate cleanly.  Concurrent shutdown and
rmmod is illegal.

I believe that this is 2.6.29 material, as it is used in some testing
setups.

For reference, here are the rcutorture operating modes:

CONFIG_RCU_TORTURE_TEST=m

	This is the normal rcutorture build.  Use "modprobe rcutorture"
	(with optional arguments) to start, and "rmmod rcutorture" to
	stop.  If you shut the system down without doing the rmmod, you
	should see console output like:

	rcutorture thread rcu_torture_writer parking due to system shutdown

	One for each rcutorture kthread.

CONFIG_RCU_TORTURE_TEST=y
CONFIG_RCU_TORTURE_TEST_RUNNABLE=n

	Use this if you want rcutorture built in, but don't want the
	test to start running during early boot.  To start the
	torturing:

		echo 1 > /proc/sys/kernel/rcutorture_runnable

	To stop the torturing, s/1/0/

	You will get "parking" console messages as noted above when
	you shut the system down.

CONFIG_RCU_TORTURE_TEST=y
CONFIG_RCU_TORTURE_TEST_RUNNABLE=y

	Same as above, except that the torturing starts during early
	boot.  Only for the stout of heart and strong of stomach.
	The same /proc entry noted above may be used to control the
	test.

Located-by: Eric Sesterhenn <snakebyte@gmx.de>
Tested-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-07 23:36:25 +01:00
Robert Richter
465634adc1 ring_buffer: fix ring_buffer_event_length()
Function ring_buffer_event_length() provides an interface to detect
the length of data stored in an entry. However, the length contains
offsets depending on the internal usage. This makes it unusable. This
patch fixes this and now ring_buffer_event_length() returns the
alligned length that has been used in ring_buffer_lock_reserve().

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07 22:47:40 +01:00
Heiko Carstens
a0e280e0f3 stop_machine/cpu hotplug: fix disable_nonboot_cpus
disable_nonboot_cpus calls _cpu_down. But _cpu_down requires that the
caller already created the stop_machine workqueue (like cpu_down does).
Otherwise a call to stop_machine will lead to accesses to random memory
regions.

When introducing this new interface (9ea09af3bd
"stop_machine: introduce stop_machine_create/destroy") I missed the second
call site of _cpu_down.
So add the missing stop_machine_create/destroy calls to disable_nonboot_cpus
as well.

Fixes suspend-to-ram/disk and also this bug:

[  286.547348] BUG: unable to handle kernel paging request at 6b6b6b6b
[  286.548940] IP: [<c0150ca4>] __stop_machine+0x88/0xe3
[  286.550598] Oops: 0002 [#1] SMP
[  286.560580] Pid: 3273, comm: halt Not tainted (2.6.28-06127-g238c6d5
[  286.560580] EIP: is at __stop_machine+0x88/0xe3
[  286.560580] Process halt (pid: 3273, ti=f1a28000 task=f4530f30
[  286.560580] Call Trace:
[  286.560580]  [<c03d04e4>] ? _cpu_down+0x10f/0x234
[  286.560580]  [<c012a57e>] ? disable_nonboot_cpus+0x58/0xdc
[  286.560580]  [<c01360c0>] ? kernel_poweroff+0x22/0x39
[  286.560580]  [<c0136301>] ? sys_reboot+0xde/0x14c
[  286.560580]  [<c01331b2>] ? complete_signal+0x179/0x191
[  286.560580]  [<c0133396>] ? send_signal+0x1cc/0x1e1
[  286.560580]  [<c03de418>] ? _spin_unlock_irqrestore+0x2d/0x3c
[  286.560580]  [<c0133b65>] ? group_send_signal_info+0x58/0x61
[  286.560580]  [<c0133b9e>] ? kill_pid_info+0x30/0x3a
[  286.560580]  [<c0133d49>] ? sys_kill+0x75/0x13a
[  286.560580]  [<c01a06cb>] ? mntput_no_expire+ox1f/0x101
[  286.560580]  [<c019b3b3>] ? dput+0x1e/0x105
[  286.560580]  [<c018ef87>] ?  __fput+0x150/0x158
[  286.560580]  [<c0157abf>] ? audit_syscall_entry+0x137/0x159
[  286.560580]  [<c010329f>] ? sysenter_do_call+0x12/0x34

Reported-and-tested-by: "Justin P. Mattock" <justinmattock@gmail.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-07 11:36:14 -08:00
Linus Torvalds
57c44c5f6f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits)
  trivial: chack -> check typo fix in main Makefile
  trivial: Add a space (and a comma) to a printk in 8250 driver
  trivial: Fix misspelling of "firmware" in docs for ncr53c8xx/sym53c8xx
  trivial: Fix misspelling of "firmware" in powerpc Makefile
  trivial: Fix misspelling of "firmware" in usb.c
  trivial: Fix misspelling of "firmware" in qla1280.c
  trivial: Fix misspelling of "firmware" in a100u2w.c
  trivial: Fix misspelling of "firmware" in megaraid.c
  trivial: Fix misspelling of "firmware" in ql4_mbx.c
  trivial: Fix misspelling of "firmware" in acpi_memhotplug.c
  trivial: Fix misspelling of "firmware" in ipw2100.c
  trivial: Fix misspelling of "firmware" in atmel.c
  trivial: Fix misspelled firmware in Kconfig
  trivial: fix an -> a typos in documentation and comments
  trivial: fix then -> than typos in comments and documentation
  trivial: update Jesper Juhl CREDITS entry with new email
  trivial: fix singal -> signal typo
  trivial: Fix incorrect use of "loose" in event.c
  trivial: printk: fix indentation of new_text_line declaration
  trivial: rtc-stk17ta8: fix sparse warning
  ...
2009-01-07 11:31:52 -08:00
Arjan van de Ven
e8de1481fd resource: allow MMIO exclusivity for device drivers
Device drivers that use pci_request_regions() (and similar APIs) have a
reasonable expectation that they are the only ones accessing their device.
As part of the e1000e hunt, we were afraid that some userland (X or some
bootsplash stuff) was mapping the MMIO region that the driver thought it
had exclusively via /dev/mem or via various sysfs resource mappings.

This patch adds the option for device drivers to cause their reserved
regions to the "banned from /dev/mem use" list, so now both kernel memory
and device-exclusive MMIO regions are banned.
NOTE: This is only active when CONFIG_STRICT_DEVMEM is set.

In addition to the config option, a kernel parameter iomem=relaxed is
provided for the cases where developers want to diagnose, in the field,
drivers issues from userspace.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:12:32 -08:00
Peter Zijlstra
490dea45d0 itimers: remove the per-cpu-ish-ness
Either we bounce once cacheline per cpu per tick, yielding n^2 bounces
or we just bounce a single..

Also, using per-cpu allocations for the thread-groups complicates the
per-cpu allocator in that its currently aimed to be a fixed sized
allocator and the only possible extention to that would be vmap based,
which is seriously constrained on 32 bit archs.

So making the per-cpu memory requirement depend on the number of
processes is an issue.

Lastly, it didn't deal with cpu-hotplug, although admittedly that might
be fixable.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-07 18:52:44 +01:00
Arjan van de Ven
ad160d2319 async: don't do the initcall stuff post boot
while tracking the asynchronous calls during boot using the initcall_debug
convention is useful, doing it once the kernel is done is actually
bad now that we use asynchronous operations post boot as well...

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2009-01-07 09:31:49 -08:00
Arjan van de Ven
22a9d64567 async: Asynchronous function calls to speed up kernel boot
Right now, most of the kernel boot is strictly synchronous, such that
various hardware delays are done sequentially.

In order to make the kernel boot faster, this patch introduces
infrastructure to allow doing some of the initialization steps
asynchronously, which will hide significant portions of the hardware delays
in practice.

In order to not change device order and other similar observables, this
patch does NOT do full parallel initialization.

Rather, it operates more in the way an out of order CPU does; the work may
be done out of order and asynchronous, but the observable effects
(instruction retiring for the CPU) are still done in the original sequence.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2009-01-07 08:45:46 -08:00
Peter Zijlstra
da8d5089da sched: fix possible recursive rq->lock
Vaidyanathan Srinivasan reported:

 > =============================================
 > [ INFO: possible recursive locking detected ]
 > 2.6.28-autotest-tip-sv #1
 > ---------------------------------------------
 > klogd/5062 is trying to acquire lock:
 >  (&rq->lock){++..}, at: [<ffffffff8022aca2>] task_rq_lock+0x45/0x7e
 >
 > but task is already holding lock:
 >  (&rq->lock){++..}, at: [<ffffffff805f7354>] schedule+0x158/0xa31

With sched_mc at 2. (it is default-off)

Strictly speaking we'll not deadlock, because ttwu will not be able to
place the migration task on our rq, but since the code can deal with
both rqs getting unlocked, this seems the easiest way out.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-07 16:10:54 +01:00
Linus Torvalds
c861ea2cb2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3]
  Revert "CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]"
  SELinux: shrink sizeof av_inhert selinux_class_perm and context
  CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]
  keys: fix sparse warning by adding __user annotation to cast
  smack: Add support for unlabeled network hosts and networks
  selinux: Deprecate and schedule the removal of the the compat_net functionality
  netlabel: Update kernel configuration API
2009-01-06 17:11:39 -08:00
Linus Torvalds
3610639d1f Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimer: splitout peek ahead functionality, fix
  hrtimer: fixup comments
  hrtimer: fix recursion deadlock by re-introducing the softirq
  hrtimer: simplify hotplug migration
  hrtimer: fix HOTPLUG_CPU=n compile warning
  hrtimer: splitout peek ahead functionality
2009-01-06 17:10:53 -08:00
Linus Torvalds
cfa97f993c Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: fix section mismatch
  sched: fix double kfree in failure path
  sched: clean up arch_reinit_sched_domains()
  sched: mark sched_create_sysfs_power_savings_entries() as __init
  getrusage: RUSAGE_THREAD should return ru_utime and ru_stime
  sched: fix sched_slice()
  sched_clock: prevent scd->clock from moving backwards, take #2
  sched: sched.c declare variables before they get used
2009-01-06 17:10:33 -08:00
Linus Torvalds
f94181da71 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: fix rcutorture bug
  rcu: eliminate synchronize_rcu_xxx macro
  rcu: make treercu safe for suspend and resume
  rcu: fix rcutree grace-period-latency bug on small systems
  futex: catch certain assymetric (get|put)_futex_key calls
  futex: make futex_(get|put)_key() calls symmetric
  locking, percpu counters: introduce separate lock classes
  swiotlb: clean up EXPORT_SYMBOL usage
  swiotlb: remove unnecessary declaration
  swiotlb: replace architecture-specific swiotlb.h with linux/swiotlb.h
  swiotlb: add support for systems with highmem
  swiotlb: store phys address in io_tlb_orig_addr array
  swiotlb: add hwdev to swiotlb_phys_to_bus() / swiotlb_sg_to_bus()
2009-01-06 17:10:04 -08:00
Linus Torvalds
40d7ee5d16 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (60 commits)
  uio: make uio_info's name and version const
  UIO: Documentation for UIO ioport info handling
  UIO: Pass information about ioports to userspace (V2)
  UIO: uio_pdrv_genirq: allow custom irq_flags
  UIO: use pci_ioremap_bar() in drivers/uio
  arm: struct device - replace bus_id with dev_name(), dev_set_name()
  libata: struct device - replace bus_id with dev_name(), dev_set_name()
  avr: struct device - replace bus_id with dev_name(), dev_set_name()
  block: struct device - replace bus_id with dev_name(), dev_set_name()
  chris: struct device - replace bus_id with dev_name(), dev_set_name()
  dmi: struct device - replace bus_id with dev_name(), dev_set_name()
  gadget: struct device - replace bus_id with dev_name(), dev_set_name()
  gpio: struct device - replace bus_id with dev_name(), dev_set_name()
  gpu: struct device - replace bus_id with dev_name(), dev_set_name()
  hwmon: struct device - replace bus_id with dev_name(), dev_set_name()
  i2o: struct device - replace bus_id with dev_name(), dev_set_name()
  IA64: struct device - replace bus_id with dev_name(), dev_set_name()
  i7300_idle: struct device - replace bus_id with dev_name(), dev_set_name()
  infiniband: struct device - replace bus_id with dev_name(), dev_set_name()
  ISDN: struct device - replace bus_id with dev_name(), dev_set_name()
  ...
2009-01-06 17:02:07 -08:00
Johannes Weiner
58c6d3dfe4 dma-coherent: catch oversized requests to dma_alloc_from_coherent()
Prevent passing an order to bitmap_find_free_region() that is larger than
the actual bitmap can represent.

These requests can come from device drivers that have no idea how big the
dma region is and need to rely on dma_alloc_from_coherent() to sort it out
for them.

Reported-by: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:31 -08:00
Andrew Morton
eccd83e116 dma_alloc_coherent: clean it up
This thing was rather stupidly coded.  Rework it all prior to making
changes.

Also, rename local variable `page': kernel readers expect something called
`page' to have type `struct page *'.

Cc: Guennadi Liakhovetski <lg@denx.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:31 -08:00
Andrew Morton
0bef3c2dc7 dma_alloc_from_coherent(): fix fallback to generic memory
If bitmap_find_free_region() fails and DMA_MEMORY_EXCLUSIVE is not set,
the function will fail to write anything to *ret and will return 1.             This will cause dma_alloc_coherent() to return an uninitialised value,
crashing the kernel, perhaps via DMA to a random address.

Fix that by changing it to return zero in this case, so the caller will
proceed to allocate the memory from the generic memory allocator.

Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:30 -08:00
Hidehiro Kawai
4cb0e11b15 coredump_filter: permit changing of the default filter
Introduce a new kernel parameter `coredump_filter'.  Setting a value to
this parameter causes the default bitmask of coredump_filter to be
changed.

It is useful for users to change coredump_filter settings for the whole
system at boot time.  Without this parameter, users have to change
coredump_filter settings for each /proc/<pid>/ in an initializing script.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:29 -08:00
Sukadev Bhattiprolu
9cd4fd1043 SEND_SIG_NOINFO: set si_pid to tgid instead of pid
POSIX requires the si_pid to be the process id of the sender, so ->si_pid
should really be set to 'tgid'.  This change does have following changes
in behavior:

	- When sending pdeath_signal on re-parent to a sub-thread, ->si_pid
	  cannot be used to identify the thread that did the re-parent since
	  it will now show the tgid instead of thread id.

	- A multi-threaded application that expects to find the specific
	  thread that encountered a SIGPIPE using the ->si_pid will now
	  break.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-By: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:29 -08:00
Sukadev Bhattiprolu
09bca05c90 SEND_SIG_NOINFO: masquerade si_pid when crossing pid-ns boundary
For SEND_SIG_NOINFO, si_pid is currently set to the pid of sender
in sender's active pid namespace. But if the receiver is in a
Eg: when parent sends the 'pdeath_signal' to a child that is in
a descendant pid namespace, we should set si_pid 0.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-By: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:28 -08:00
Randy Dunlap
bd4207c901 kmod: fix varargs kernel-doc
Fix varargs kernel-doc format in kmod.c:
Use @... instead of @varargs.

Warning(kernel/kmod.c:67): Excess function parameter or struct member 'varargs' description in 'request_module'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:27 -08:00
Masami Hiramatsu
f24659d96f kprobes: support probing module __init function
Allow kprobes to probe module __init routines.  When __init functions are
freed, kprobes which probe those functions are set to "Gone" flag.  These
"Gone" probes are disarmed from the code and never be enabled.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:21 -08:00
Masami Hiramatsu
0deddf436a module: add MODULE_STATE_LIVE notify
Add a module notifier call which notifies that the state of a module
changes from MODULE_STATE_COMING to MODULE_STATE_LIVE.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:21 -08:00
Masami Hiramatsu
49ad2fd76c kprobes: remove called_from argument
Remove called_from argument from kprobes which had been used for
preventing self-refering of kernel module.  However, since we don't keep
module's refcount after registering kprobe any more, there is no reason to
check that.

This patch also simplifies registering/unregistering functions because we
don't need to use __builtin_return_address(0) which was passed to
called_from.

[ananth@in.ibm.com: build fix]
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:21 -08:00
Masami Hiramatsu
e8386a0cb2 kprobes: support probing module __exit function
Allows kprobes to probe __exit routine.  This adds flags member to struct
kprobe.  When module is freed(kprobes hooks module_notifier to get this
event), kprobes which probe the functions in that module are set to "Gone"
flag to the flags member.  These "Gone" probes are never be enabled.
Users can check the GONE flag through debugfs.

This also removes mod_refcounted, because we couldn't free a module if
kprobe incremented the refcount of that module.

[akpm@linux-foundation.org: document some locking]
[mhiramat@redhat.com: bugfix: pass aggr_kprobe to arch_remove_kprobe]
[mhiramat@redhat.com: bugfix: release old_p's insn_slot before error return]
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:21 -08:00
Masami Hiramatsu
017c39bdb1 kprobes: add __kprobes to kprobe internal functions
Add __kprobes to kprobes internal functions for protecting from probing by
kprobes itself.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
Masami Hiramatsu
1294156078 kprobes: add kprobe_insn_mutex and cleanup arch_remove_kprobe()
Add kprobe_insn_mutex for protecting kprobe_insn_pages hlist, and remove
kprobe_mutex from architecture dependent code.

This allows us to call arch_remove_kprobe() (and free_insn_slot) while
holding kprobe_mutex.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
Masami Hiramatsu
a06f6211ef module: add within_module_core() and within_module_init()
This series of patches allows kprobes to probe module's __init and __exit
functions.  This means, you can probe driver initialization and
terminating.

Currently, kprobes can't probe __init function because these functions are
freed after module initialization.  And it also can't probe module __exit
functions because kprobe increments reference count of target module and
user can't unload it.  this means __exit functions never be called unless
removing probes from the module.

To solve both cases, this series of patches introduces GONE flag and sets
it when the target code is freed(for this purpose, kprobes hooks
MODULE_STATE_* events).  This also removes refcount incrementing for
allowing user to unload target module.  Users can check which probes are
GONE by debugfs interface.  For taking timing of freeing module's .init
text, these also include a patch which adds module's notifier of
MODULE_STATE_LIVE event.

This patch:

Add within_module_core() and within_module_init() for checking whether an
address is in the module .init.text section or .text section, and replace
within() local inline functions in kernel/module.c with them.

kprobes uses these functions to check where the kprobe is inserted.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
Masami Hiramatsu
12da3b888b kprobes: add tests for register_kprobes
Add testcases for *probe batch registration (register_kprobes) to kprobes
sanity tests.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: David Miller <davem@davemloft.net>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
Masami Hiramatsu
8e1144050e kprobes: indirectly call kprobe_target
Call kprobe_target indirectly.  This prevents gcc to unroll a noinline
function in caller function.

I ported patches which had been discussed on
http://sources.redhat.com/bugzilla/show_bug.cgi?id=3542

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: David Miller <davem@davemloft.net>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
Masami Hiramatsu
bc2f70151f kprobes: bugfix: try_module_get even if calling_mod is NULL
When someone called register_*probe() from kernel-core code(not from
module) and that probes a kernel module, users can remove the probed
module because kprobe doesn't increment reference counter of the module.
(on the other hand, if the kernel-module calls register_*probe, kprobe
increments refcount of the probed module.)

Currently, we have no register_*probe() calling from kernel-core(except
smoke-test, but the smoke-test doesn't probe module), so there is no real
bugs.  But the logic is wrong(or not fair) and it can causes a problem
when someone might want to probe module from kernel.

After this patch is applied, even if someone put register_*probe() call in
the kernel-core code, it increments the reference counter of the probed
module, and it prevents user to remove the module until stopping probing
it.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00
KOSAKI Motohiro
26e5438e4b profile: don't include <asm/ptrace.h> twice.
Currently, kernel/profile.c include <asm/ptrace.h> twice.  It can be
removed.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:14 -08:00
Paul Mackerras
e3d5a27d58 Allow times and time system calls to return small negative values
At the moment, the times() system call will appear to fail for a period
shortly after boot, while the value it want to return is between -4095 and
-1.  The same thing will also happen for the time() system call on 32-bit
platforms some time in 2106 or so.

On some platforms, such as x86, this is unavoidable because of the system
call ABI, but other platforms such as powerpc have a separate error
indication from the return value, so system calls can in fact return small
negative values without indicating an error.  On those platforms,
force_successful_syscall_return() provides a way to indicate that the
system call return value should not be treated as an error even if it is
in the range which would normally be taken as a negative error number.

This adds a force_successful_syscall_return() call to the time() and
times() system calls plus their 32-bit compat versions, so that they don't
erroneously indicate an error on those platforms whose system call ABI has
a separate error indication.  This will not affect anything on other
platforms.

Joakim Tjernlund added the fix for time() and the compat versions of
time() and times(), after I did the fix for times().

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:13 -08:00
Arjan van de Ven
d6624f996a oops: increment the oops UUID every time we oops
... because we do want repeated same-oops to be seen by automated
tools like kerneloops.org

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:12 -08:00
Zhaolei
60348802e9 fork.c: cleanup for copy_sighand()
Check CLONE_SIGHAND only is enough, because combination of CLONE_THREAD and
CLONE_SIGHAND is already done in copy_process().

Impact: cleanup, no functionality changed

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:11 -08:00
Alexey Dobriyan
f1883f86de Remove remaining unwinder code
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Gabor Gombas <gombasg@sztaki.hu>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:11 -08:00
Oleg Nesterov
901608d904 mm: introduce get_mm_hiwater_xxx(), fix taskstats->hiwater_xxx accounting
xacct_add_tsk() relies on do_exit()->update_hiwater_xxx() and uses
mm->hiwater_xxx directly, this leads to 2 problems:

- taskstats_user_cmd() can call fill_pid()->xacct_add_tsk() at any
  moment before the task exits, so we should check the current values of
  rss/vm anyway.

- do_exit()->update_hiwater_xxx() calls are racy.  An exiting thread can
  be preempted right before mm->hiwater_xxx = new_val, and another thread
  can use A_LOT of memory and exit in between.  When the first thread
  resumes it can be the last thread in the thread group, in that case we
  report the wrong hiwater_xxx values which do not take A_LOT into
  account.

Introduce get_mm_hiwater_rss() and get_mm_hiwater_vm() helpers and change
xacct_add_tsk() to use them.  The first helper will also be used by
rusage->ru_maxrss accounting.

Kill do_exit()->update_hiwater_xxx() calls.  Unless we are going to
decrease rss/vm there is no point to update mm->hiwater_xxx, and nobody
can look at this mm_struct when exit_mmap() actually unmaps the memory.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:09 -08:00
David Rientjes
2da02997e0 mm: add dirty_background_bytes and dirty_bytes sysctls
This change introduces two new sysctls to /proc/sys/vm:
dirty_background_bytes and dirty_bytes.

dirty_background_bytes is the counterpart to dirty_background_ratio and
dirty_bytes is the counterpart to dirty_ratio.

With growing memory capacities of individual machines, it's no longer
sufficient to specify dirty thresholds as a percentage of the amount of
dirtyable memory over the entire system.

dirty_background_bytes and dirty_bytes specify quantities of memory, in
bytes, that represent the dirty limits for the entire system.  If either
of these values is set, its value represents the amount of dirty memory
that is needed to commence either background or direct writeback.

When a `bytes' or `ratio' file is written, its counterpart becomes a
function of the written value.  For example, if dirty_bytes is written to
be 8096, 8K of memory is required to commence direct writeback.
dirty_ratio is then functionally equivalent to 8K / the amount of
dirtyable memory:

	dirtyable_memory = free pages + mapped pages + file cache

	dirty_background_bytes = dirty_background_ratio * dirtyable_memory
		-or-
	dirty_background_ratio = dirty_background_bytes / dirtyable_memory

		AND

	dirty_bytes = dirty_ratio * dirtyable_memory
		-or-
	dirty_ratio = dirty_bytes / dirtyable_memory

Only one of dirty_background_bytes and dirty_background_ratio may be
specified at a time, and only one of dirty_bytes and dirty_ratio may be
specified.  When one sysctl is written, the other appears as 0 when read.

The `bytes' files operate on a page size granularity since dirty limits
are compared with ZVC values, which are in page units.

Prior to this change, the minimum dirty_ratio was 5 as implemented by
get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user
written value between 0 and 100.  This restriction is maintained, but
dirty_bytes has a lower limit of only one page.

Also prior to this change, the dirty_background_ratio could not equal or
exceed dirty_ratio.  This restriction is maintained in addition to
restricting dirty_background_bytes.  If either background threshold equals
or exceeds that of the dirty threshold, it is implicitly set to half the
dirty threshold.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:03 -08:00
Hugh Dickins
e5991371ee mm: remove cgroup_mm_owner_callbacks
cgroup_mm_owner_callbacks() was brought in to support the memrlimit
controller, but sneaked into mainline ahead of it.  That controller has
now been shelved, and the mm_owner_changed() args were inadequate for it
anyway (they needed an mm pointer instead of a task pointer).

Remove the dead code, and restore mm_update_next_owner() locking to how it
was before: taking mmap_sem there does nothing for memcontrol.c, now the
only user of mm->owner.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:01 -08:00
David Rientjes
75aa199410 oom: print triggering task's cpuset and mems allowed
When cpusets are enabled, it's necessary to print the triggering task's
set of allowable nodes so the subsequently printed meminfo can be
interpreted correctly.

We also print the task's cpuset name for informational purposes.

[rientjes@google.com: task lock current before dereferencing cpuset]
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:58:59 -08:00
James Morris
ac8cc0fa53 Merge branch 'next' into for-linus 2009-01-07 09:58:22 +11:00
David Howells
3699c53c48 CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3]
Fix a regression in cap_capable() due to:

	commit 3b11a1dece
	Author: David Howells <dhowells@redhat.com>
	Date:   Fri Nov 14 10:39:26 2008 +1100

	    CRED: Differentiate objective and effective subjective credentials on a task

The problem is that the above patch allows a process to have two sets of
credentials, and for the most part uses the subjective credentials when
accessing current's creds.

There is, however, one exception: cap_capable(), and thus capable(), uses the
real/objective credentials of the target task, whether or not it is the current
task.

Ordinarily this doesn't matter, since usually the two cred pointers in current
point to the same set of creds.  However, sys_faccessat() makes use of this
facility to override the credentials of the calling process to make its test,
without affecting the creds as seen from other processes.

One of the things sys_faccessat() does is to make an adjustment to the
effective capabilities mask, which cap_capable(), as it stands, then ignores.

The affected capability check is in generic_permission():

	if (!(mask & MAY_EXEC) || execute_ok(inode))
		if (capable(CAP_DAC_OVERRIDE))
			return 0;

This change passes the set of credentials to be tested down into the commoncap
and SELinux code.  The security functions called by capable() and
has_capability() select the appropriate set of credentials from the process
being checked.

This can be tested by compiling the following program from the XFS testsuite:

/*
 *  t_access_root.c - trivial test program to show permission bug.
 *
 *  Written by Michael Kerrisk - copyright ownership not pursued.
 *  Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html
 */
#include <limits.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>

#define UID 500
#define GID 100
#define PERM 0
#define TESTPATH "/tmp/t_access"

static void
errExit(char *msg)
{
    perror(msg);
    exit(EXIT_FAILURE);
} /* errExit */

static void
accessTest(char *file, int mask, char *mstr)
{
    printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask));
} /* accessTest */

int
main(int argc, char *argv[])
{
    int fd, perm, uid, gid;
    char *testpath;
    char cmd[PATH_MAX + 20];

    testpath = (argc > 1) ? argv[1] : TESTPATH;
    perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM;
    uid = (argc > 3) ? atoi(argv[3]) : UID;
    gid = (argc > 4) ? atoi(argv[4]) : GID;

    unlink(testpath);

    fd = open(testpath, O_RDWR | O_CREAT, 0);
    if (fd == -1) errExit("open");

    if (fchown(fd, uid, gid) == -1) errExit("fchown");
    if (fchmod(fd, perm) == -1) errExit("fchmod");
    close(fd);

    snprintf(cmd, sizeof(cmd), "ls -l %s", testpath);
    system(cmd);

    if (seteuid(uid) == -1) errExit("seteuid");

    accessTest(testpath, 0, "0");
    accessTest(testpath, R_OK, "R_OK");
    accessTest(testpath, W_OK, "W_OK");
    accessTest(testpath, X_OK, "X_OK");
    accessTest(testpath, R_OK | W_OK, "R_OK | W_OK");
    accessTest(testpath, R_OK | X_OK, "R_OK | X_OK");
    accessTest(testpath, W_OK | X_OK, "W_OK | X_OK");
    accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK");

    exit(EXIT_SUCCESS);
} /* main */

This can be run against an Ext3 filesystem as well as against an XFS
filesystem.  If successful, it will show:

	[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
	---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx
	access(/tmp/xxx, 0) returns 0
	access(/tmp/xxx, R_OK) returns 0
	access(/tmp/xxx, W_OK) returns 0
	access(/tmp/xxx, X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK) returns 0
	access(/tmp/xxx, R_OK | X_OK) returns -1
	access(/tmp/xxx, W_OK | X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1

If unsuccessful, it will show:

	[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
	---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx
	access(/tmp/xxx, 0) returns 0
	access(/tmp/xxx, R_OK) returns -1
	access(/tmp/xxx, W_OK) returns -1
	access(/tmp/xxx, X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK) returns -1
	access(/tmp/xxx, R_OK | X_OK) returns -1
	access(/tmp/xxx, W_OK | X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1

I've also tested the fix with the SELinux and syscalls LTP testsuites.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-01-07 09:38:48 +11:00
James Morris
29881c4502 Revert "CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]"
This reverts commit 14eaddc967.

David has a better version to come.
2009-01-07 09:21:54 +11:00
Kay Sievers
81ff86a11f pm: struct device - replace bus_id with dev_name(), dev_set_name()
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:39 -08:00
Ming Lei
cd3772e689 kernel/ksysfs.c:fix dependence on CONFIG_NET
Access to uevent_seqnum and uevent_helper does not need to
depend on CONFIG_NET, so remove it.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:31 -08:00
Frederik Schwarzer
025dfdafe7 trivial: fix then -> than typos in comments and documentation
- (better, more, bigger ...) then -> (...) than

Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06 11:28:06 +01:00
Jiri Kosina
edb123e16c trivial: printk: fix indentation of new_text_line declaration
Remove bogus indentation of new_text_line declaration introduced in
commit ac60ad741.

Acked-by: Nick Andrew <nick@nick-andrew.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06 11:28:06 +01:00
Li Zefan
db2f59c8c9 sched: fix section mismatch
init_rootdomain() calls alloc_bootmem_cpumask_var() at system boot,
so does cpupri_init().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-06 11:07:15 +01:00
Li Zefan
0c910d2895 sched: fix double kfree in failure path
It's not the responsibility of init_rootdomain() to free root_domain
allocated by alloc_rootdomain().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-06 11:07:04 +01:00
Ingo Molnar
d9be28ea91 Merge branches 'sched/clock', 'sched/cleanups' and 'linus' into sched/urgent 2009-01-06 09:33:57 +01:00
Ingo Molnar
fdbc0450df Merge branches 'core/futexes', 'core/locking', 'core/rcu' and 'linus' into core/urgent 2009-01-06 09:32:11 +01:00
Linus Torvalds
0bbb275358 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: convert to stop_machine_create/destroy.
  stop_machine: introduce stop_machine_create/destroy.
  parisc: fix module loading failure of large kernel modules
  module: fix module loading failure of large kernel modules for parisc
  module: fix warning of unused function when !CONFIG_PROC_FS
  kernel/module.c: compare symbol values when marking symbols as exported in /proc/kallsyms.
  remove CONFIG_KMOD
2009-01-05 19:03:39 -08:00
Linus Torvalds
520c853466 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  inotify: fix type errors in interfaces
  fix breakage in reiserfs_new_inode()
  fix the treatment of jfs special inodes
  vfs: remove duplicate code in get_fs_type()
  add a vfs_fsync helper
  sys_execve and sys_uselib do not call into fsnotify
  zero i_uid/i_gid on inode allocation
  inode->i_op is never NULL
  ntfs: don't NULL i_op
  isofs check for NULL ->i_op in root directory is dead code
  affs: do not zero ->i_op
  kill suid bit only for regular files
  vfs: lseek(fd, 0, SEEK_CUR) race condition
2009-01-05 18:32:06 -08:00
Al Viro
56ff5efad9 zero i_uid/i_gid on inode allocation
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-05 11:54:28 -05:00
Ingo Molnar
82c5b7b527 hrtimer: splitout peek ahead functionality, fix
Impact: build fix on !CONFIG_HIGH_RES_TIMERS

Fix:

  kernel/hrtimer.c:1586: error: implicit declaration of function '__hrtimer_peek_ahead_timers'

Signen-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 14:11:10 +01:00
Li Zefan
c70f22d203 sched: clean up arch_reinit_sched_domains()
- Make arch_reinit_sched_domains() static. It was exported to be used in
  s390, but now rebuild_sched_domains() is used instead.

- Make it return void.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:54:16 +01:00
Li Zefan
39aac64812 sched: mark sched_create_sysfs_power_savings_entries() as __init
Impact: cleanup

The only caller is cpu_dev_init() which is marked as __init.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:54:16 +01:00
Ingo Molnar
5359c32eb7 Merge branch 'linus' into sched/urgent 2009-01-05 13:53:39 +01:00
Thomas Gleixner
e3f1d88374 hrtimer: fixup comments
Clean up the comments

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:34 +01:00
Peter Zijlstra
a6037b61c2 hrtimer: fix recursion deadlock by re-introducing the softirq
Impact: fix rare runtime deadlock

There are a few sites that do:

  spin_lock_irq(&foo)
  hrtimer_start(&bar)
    __run_hrtimer(&bar)
      func()
        spin_lock(&foo)

which obviously deadlocks. In order to avoid this, never call __run_hrtimer()
from hrtimer_start*() context, but instead defer this to softirq context.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:33 +01:00
Thomas Gleixner
731a55ba0f hrtimer: simplify hotplug migration
Impact: cleanup

No need for a smp function call, which is likely to run on the same
CPU anyway. We can just call hrtimers_peek_ahead() in the interrupts
disabled section of migrate_hrtimers().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:33 +01:00
Thomas Gleixner
d5fd43c4ae hrtimer: fix HOTPLUG_CPU=n compile warning
Impact: cleanup

 kernel/hrtimer.c: In function 'hrtimer_cpu_notify':
 kernel/hrtimer.c:1574: warning: unused variable 'dcpu'

Introduced by commit 37810659ea
("hrtimer: removing all ur callback modes, fix hotplug") from the
timers.  dcpu is only used if CONFIG_HOTPLUG_CPU is set.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:32 +01:00
Thomas Gleixner
8bdec955b0 hrtimer: splitout peek ahead functionality
Impact: cleanup

Provide a peek ahead function that assumes irqs disabled, allows for micro
optimizations.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:32 +01:00
Paul E. McKenney
c59ab97e9e rcu: fix rcutorture bug
Fix an rcutorture bug that prevents the shutdown notifier from ever
actually having any effect, due to the fact that kthreads ignore all
signals.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:09:49 +01:00
Paul E. McKenney
ea7d3fef42 rcu: eliminate synchronize_rcu_xxx macro
Impact: cleanup

Expand macro into two files.

The synchronize_rcu_xxx macro is quite ugly and it's only used by two
callers, so expand it instead.  This makes this code easier to change.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 10:18:08 +01:00
Paul E. McKenney
90a4d2c010 rcu: make treercu safe for suspend and resume
Impact: fix kernel warnings [and potential crash] during suspend+resume

Kudos to both Dhaval Giani and Jens Axboe for finding a bug in treercu
that causes warnings after suspend-resume cycles in Dhaval's case and
during stress tests in Jens's case.  It would also probably cause failures
if heavily stressed.  The solution, ironically enough, is to revert to
rcupreempt's code for initializing the dynticks state.  And the patch
even results in smaller code -- so what was I thinking???

This is 2.6.29 material, given that people really do suspend and resume
Linux these days.  ;-)

Reported-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Reported-by: Jens Axboe <jens.axboe@oracle.com>
Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Tested-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 10:12:33 +01:00
Paul E. McKenney
c12172c025 rcu: fix rcutree grace-period-latency bug on small systems
Impact: fix delays during bootup

Kudos to Andi Kleen for finding a grace-period-latency problem!  The
problem was that the special-case code for small machines never updated
the ->signaled field to indicate that grace-period initialization had
completed, which prevented force_quiescent_state() from ever expediting
grace periods.  This problem resulted in grace periods extending for more
than 20 seconds.  Not subtle.  I introduced this bug during my inspection
process when I fixed a race between grace-period initialization and
force_quiescent_state() execution.

The following patch properly updates the ->signaled field for the
"small"-system case (no more than 32 CPUs for 32-bit kernels and no more
than 64 CPUs for 64-bit kernels).

Reported-by: Andi Kleen <andi@firstfloor.org>
Tested-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 10:10:28 +01:00
Linus Torvalds
fe0bdec68b Merge branch 'audit.b61' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b61' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  audit: validate comparison operations, store them in sane form
  clean up audit_rule_{add,del} a bit
  make sure that filterkey of task,always rules is reported
  audit rules ordering, part 2
  fixing audit rule ordering mess, part 1
  audit_update_lsm_rules() misses the audit_inode_hash[] ones
  sanitize audit_log_capset()
  sanitize audit_fd_pair()
  sanitize audit_mq_open()
  sanitize AUDIT_MQ_SENDRECV
  sanitize audit_mq_notify()
  sanitize audit_mq_getsetattr()
  sanitize audit_ipc_set_perm()
  sanitize audit_ipc_obj()
  sanitize audit_socketcall
  don't reallocate buffer in every audit_sockaddr()
2009-01-04 16:32:11 -08:00
David Howells
14eaddc967 CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]
Fix a regression in cap_capable() due to:

	commit 5ff7711e635b32f0a1e558227d030c7e45b4a465
	Author: David Howells <dhowells@redhat.com>
	Date:   Wed Dec 31 02:52:28 2008 +0000

	    CRED: Differentiate objective and effective subjective credentials on a task

The problem is that the above patch allows a process to have two sets of
credentials, and for the most part uses the subjective credentials when
accessing current's creds.

There is, however, one exception: cap_capable(), and thus capable(), uses the
real/objective credentials of the target task, whether or not it is the current
task.

Ordinarily this doesn't matter, since usually the two cred pointers in current
point to the same set of creds.  However, sys_faccessat() makes use of this
facility to override the credentials of the calling process to make its test,
without affecting the creds as seen from other processes.

One of the things sys_faccessat() does is to make an adjustment to the
effective capabilities mask, which cap_capable(), as it stands, then ignores.

The affected capability check is in generic_permission():

	if (!(mask & MAY_EXEC) || execute_ok(inode))
		if (capable(CAP_DAC_OVERRIDE))
			return 0;

This change splits capable() from has_capability() down into the commoncap and
SELinux code.  The capable() security op now only deals with the current
process, and uses the current process's subjective creds.  A new security op -
task_capable() - is introduced that can check any task's objective creds.

strictly the capable() security op is superfluous with the presence of the
task_capable() op, however it should be faster to call the capable() op since
two fewer arguments need be passed down through the various layers.

This can be tested by compiling the following program from the XFS testsuite:

/*
 *  t_access_root.c - trivial test program to show permission bug.
 *
 *  Written by Michael Kerrisk - copyright ownership not pursued.
 *  Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html
 */
#include <limits.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>

#define UID 500
#define GID 100
#define PERM 0
#define TESTPATH "/tmp/t_access"

static void
errExit(char *msg)
{
    perror(msg);
    exit(EXIT_FAILURE);
} /* errExit */

static void
accessTest(char *file, int mask, char *mstr)
{
    printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask));
} /* accessTest */

int
main(int argc, char *argv[])
{
    int fd, perm, uid, gid;
    char *testpath;
    char cmd[PATH_MAX + 20];

    testpath = (argc > 1) ? argv[1] : TESTPATH;
    perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM;
    uid = (argc > 3) ? atoi(argv[3]) : UID;
    gid = (argc > 4) ? atoi(argv[4]) : GID;

    unlink(testpath);

    fd = open(testpath, O_RDWR | O_CREAT, 0);
    if (fd == -1) errExit("open");

    if (fchown(fd, uid, gid) == -1) errExit("fchown");
    if (fchmod(fd, perm) == -1) errExit("fchmod");
    close(fd);

    snprintf(cmd, sizeof(cmd), "ls -l %s", testpath);
    system(cmd);

    if (seteuid(uid) == -1) errExit("seteuid");

    accessTest(testpath, 0, "0");
    accessTest(testpath, R_OK, "R_OK");
    accessTest(testpath, W_OK, "W_OK");
    accessTest(testpath, X_OK, "X_OK");
    accessTest(testpath, R_OK | W_OK, "R_OK | W_OK");
    accessTest(testpath, R_OK | X_OK, "R_OK | X_OK");
    accessTest(testpath, W_OK | X_OK, "W_OK | X_OK");
    accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK");

    exit(EXIT_SUCCESS);
} /* main */

This can be run against an Ext3 filesystem as well as against an XFS
filesystem.  If successful, it will show:

	[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
	---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx
	access(/tmp/xxx, 0) returns 0
	access(/tmp/xxx, R_OK) returns 0
	access(/tmp/xxx, W_OK) returns 0
	access(/tmp/xxx, X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK) returns 0
	access(/tmp/xxx, R_OK | X_OK) returns -1
	access(/tmp/xxx, W_OK | X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1

If unsuccessful, it will show:

	[root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043
	---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx
	access(/tmp/xxx, 0) returns 0
	access(/tmp/xxx, R_OK) returns -1
	access(/tmp/xxx, W_OK) returns -1
	access(/tmp/xxx, X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK) returns -1
	access(/tmp/xxx, R_OK | X_OK) returns -1
	access(/tmp/xxx, W_OK | X_OK) returns -1
	access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1

I've also tested the fix with the SELinux and syscalls LTP testsuites.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-01-05 11:17:04 +11:00
Heiko Carstens
9e01892c42 module: convert to stop_machine_create/destroy.
The module code relies on a non-failing stop_machine call. So we create
the kstop threads in advance and with that make sure the call won't fail.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-05 08:40:15 +10:30
Heiko Carstens
9ea09af3bd stop_machine: introduce stop_machine_create/destroy.
Introduce stop_machine_create/destroy. With this interface subsystems
that need a non-failing stop_machine environment can create the
stop_machine machine threads before actually calling stop_machine.
When the threads aren't needed anymore they can be killed with
stop_machine_destroy again.

When stop_machine gets called and the threads aren't present they
will be created and destroyed automatically. This restores the old
behaviour of stop_machine.

This patch also converts cpu hotplug to the new interface since it
is special: cpu_down calls __stop_machine instead of stop_machine.
However the kstop threads will only be created when stop_machine
gets called.

Changing the code so that the threads would be created automatically
on __stop_machine is currently not possible: when __stop_machine gets
called we hold cpu_add_remove_lock, which is the same lock that
create_rt_workqueue would take. So the workqueue needs to be created
before the cpu hotplug code locks cpu_add_remove_lock.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-05 08:40:14 +10:30
Helge Deller
088af9a6e0 module: fix module loading failure of large kernel modules for parisc
When creating the final layout of a kernel module in memory, allow the
module loader to reserve some additional memory in front of a given section.
This is currently only needed for the parisc port which needs to put the
stub entries there to fulfill the 17/22bit PCREL relocations with large
kernel modules like xfs.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (renamed fn)
2009-01-05 08:40:13 +10:30
Jianjun Kong
d1e99d7ae4 module: fix warning of unused function when !CONFIG_PROC_FS
Fix this warning:
kernel/module.c:824: warning: ‘print_unload_info’ defined but not used
print_unload_info() just was used when CONFIG_PROC_FS was defined.
This patch mark print_unload_info() inline to solve the problem.

Signed-off-by: Jianjun Kong <jianjun@zeuux.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CC: Ingo Molnar <mingo@elte.hu>
CC: Américo Wang <xiyou.wangcong@gmail.com>
2009-01-05 08:40:11 +10:30
Tim Abbott
ca4787b779 kernel/module.c: compare symbol values when marking symbols as exported in /proc/kallsyms.
When there are two symbols in a module with the same name, one of which is
exported, both will be marked as exported in /proc/kallsyms.  There aren't
any instances of this in the current kernel, but it is easy to construct a
simple module with two compilation units that exhibits the problem.

$ objdump -j .text -t testmod.ko | grep foo
00000000 l     F .text	00000032 foo
00000080 g     F .text	00000001 foo
$ sudo insmod testmod.ko
$ grep "T foo" /proc/kallsyms
c28e8000 T foo	[testmod]
c28e8080 T foo	[testmod]

Fix this by comparing the symbol values once we've found the exported
symbol table entry matching the symbol name.  Tested using Ksplice:

$ ksplice-create --patch=this_commit.patch --id=bar .
$ sudo ksplice-apply ksplice-bar.tar.gz
Done!
$ grep "T foo" /proc/kallsyms
c28e8080 T foo	[testmod]

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-05 08:40:11 +10:30
Li Zefan
7b574b7b01 cgroups: fix a race between cgroup_clone and umount
The race is calling cgroup_clone() while umounting the ns cgroup subsys,
and thus cgroup_clone() might access invalid cgroup_fs, or kill_sb() is
called after cgroup_clone() created a new dir in it.

The BUG I triggered is BUG_ON(root->number_of_cgroups != 1);

  ------------[ cut here ]------------
  kernel BUG at kernel/cgroup.c:1093!
  invalid opcode: 0000 [#1] SMP
  ...
  Process umount (pid: 5177, ti=e411e000 task=e40c4670 task.ti=e411e000)
  ...
  Call Trace:
   [<c0493df7>] ? deactivate_super+0x3f/0x51
   [<c04a3600>] ? mntput_no_expire+0xb3/0xdd
   [<c04a3ab2>] ? sys_umount+0x265/0x2ac
   [<c04a3b06>] ? sys_oldumount+0xd/0xf
   [<c0403911>] ? sysenter_do_call+0x12/0x31
  ...
  EIP: [<c0456e76>] cgroup_kill_sb+0x23/0xe0 SS:ESP 0068:e411ef2c
  ---[ end trace c766c1be3bf944ac ]---

Cc: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:19 -08:00
Al Viro
5af75d8d58 audit: validate comparison operations, store them in sane form
Don't store the field->op in the messy (and very inconvenient for e.g.
audit_comparator()) form; translate to dense set of values and do full
validation of userland-submitted value while we are at it.

->audit_init_rule() and ->audit_match_rule() get new values now; in-tree
instances updated.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:42 -05:00
Al Viro
36c4f1b18c clean up audit_rule_{add,del} a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:42 -05:00
Al Viro
e048e02c89 make sure that filterkey of task,always rules is reported
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:42 -05:00
Al Viro
e45aa212ea audit rules ordering, part 2
Fix the actual rule listing; add per-type lists _not_ used for matching,
with all exit,... sitting on one such list.  Simplifies "do something
for all rules" logics, while we are at it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:42 -05:00
Al Viro
0590b9335a fixing audit rule ordering mess, part 1
Problem: ordering between the rules on exit chain is currently lost;
all watch and inode rules are listed after everything else _and_
exit,never on one kind doesn't stop exit,always on another from
being matched.

Solution: assign priorities to rules, keep track of the current
highest-priority matching rule and its result (always/never).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro
1a9d0797b8 audit_update_lsm_rules() misses the audit_inode_hash[] ones
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro
57f71a0af4 sanitize audit_log_capset()
* no allocations
* return void
* don't duplicate checked for dummy context

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro
157cf649a7 sanitize audit_fd_pair()
* no allocations
* return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro
564f6993ff sanitize audit_mq_open()
* don't bother with allocations
* don't do double copy_from_user()
* don't duplicate parts of check for audit_dummy_context()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro
c32c8af43b sanitize AUDIT_MQ_SENDRECV
* logging the original value of *msg_prio in mq_timedreceive(2)
  is insane - the argument is write-only (i.e. syscall always
  ignores the original value and only overwrites it).
* merge __audit_mq_timed{send,receive}
* don't do copy_from_user() twice
* don't mess with allocations in auditsc part
* ... and don't bother checking !audit_enabled and !context in there -
  we'd already checked for audit_dummy_context().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro
20114f71b2 sanitize audit_mq_notify()
* don't copy_from_user() twice
* don't bother with allocations
* don't duplicate parts of audit_dummy_context()
* make it return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro
7392906ea9 sanitize audit_mq_getsetattr()
* get rid of allocations
* make it return void
* don't duplicate parts of audit_dummy_context()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro
e816f370cb sanitize audit_ipc_set_perm()
* get rid of allocations
* make it return void
* simplify callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro
a33e675100 sanitize audit_ipc_obj()
* get rid of allocations
* make it return void
* simplify callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:39 -05:00
Al Viro
f3298dc4f2 sanitize audit_socketcall
* don't bother with allocations
* now that it can't fail, make it return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:39 -05:00
Al Viro
4f6b434fee don't reallocate buffer in every audit_sockaddr()
No need to do that more than once per process lifetime; allocating/freeing
on each sendto/accept/etc. is bloody pointless.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:39 -05:00
KOSAKI Motohiro
8916edef58 getrusage: RUSAGE_THREAD should return ru_utime and ru_stime
Impact: task stats regression fix

Original getrusage(RUSAGE_THREAD) implementation can return ru_utime and
ru_stime. But commit "f06febc: timers: fix itimer/many thread hang" broke it.

this patch restores it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-04 14:04:00 +01:00
Linus Torvalds
7d3b56ba37 Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits)
  x86: setup_per_cpu_areas() cleanup
  cpumask: fix compile error when CONFIG_NR_CPUS is not defined
  cpumask: use alloc_cpumask_var_node where appropriate
  cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t
  x86: use cpumask_var_t in acpi/boot.c
  x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids
  sched: put back some stack hog changes that were undone in kernel/sched.c
  x86: enable cpus display of kernel_max and offlined cpus
  ia64: cpumask fix for is_affinity_mask_valid()
  cpumask: convert RCU implementations, fix
  xtensa: define __fls
  mn10300: define __fls
  m32r: define __fls
  h8300: define __fls
  frv: define __fls
  cris: define __fls
  cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
  cpumask: zero extra bits in alloc_cpumask_var_node
  cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
  cpumask: convert mm/
  ...
2009-01-03 12:04:39 -08:00
Linus Torvalds
61420f59a5 Merge branch 'cputime' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
* 'cputime' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_ID
  [PATCH] improve idle cputime accounting
  [PATCH] improve precision of idle time detection.
  [PATCH] improve precision of process accounting.
  [PATCH] idle cputime accounting
  [PATCH] fix scaled & unscaled cputime accounting
2009-01-03 11:56:24 -08:00
Mike Travis
6ca09dfc9f sched: put back some stack hog changes that were undone in kernel/sched.c
Impact: prevents panic from stack overflow on numa-capable machines.

Some of the "removal of stack hogs" changes in kernel/sched.c by using
node_to_cpumask_ptr were undone by the early cpumask API updates, and
causes a panic due to stack overflow.  This patch undoes those changes
by using cpumask_of_node() which returns a 'const struct cpumask *'.

In addition, cpu_coregoup_map is replaced with cpu_coregroup_mask further
reducing stack usage.  (Both of these updates removed 9 FIXME's!)

Also:
   Pick up some remaining changes from the old 'cpumask_t' functions to
   the new 'struct cpumask *' functions.

   Optimize memory traffic by allocating each percpu local_cpu_mask on the
   same node as the referring cpu.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-03 19:00:09 +01:00
Ingo Molnar
6bdf197b04 ia64: cpumask fix for is_affinity_mask_valid()
Impact: build fix on ia64

ia64's default_affinity_write() still had old cpumask_t usage:

 /home/mingo/tip/kernel/irq/proc.c: In function `default_affinity_write':
 /home/mingo/tip/kernel/irq/proc.c:114: error: incompatible type for argument 1 of `is_affinity_mask_valid'
 make[3]: *** [kernel/irq/proc.o] Error 1
 make[3]: *** Waiting for unfinished jobs....

update it to cpumask_var_t.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-03 18:59:33 +01:00
Ingo Molnar
263ec6457b cpumask: convert RCU implementations, fix
Impact: cleanup

This warning:

 kernel/rcuclassic.c: In function ‘rcu_start_batch’:
 kernel/rcuclassic.c:397: warning: passing argument 1 of ‘cpumask_andnot’ from incompatible pointer type

triggers because one usage site of rcp->cpumask was not converted
to to_cpumask(rcp->cpumask). There's no ill effects of this bug.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-03 18:59:25 +01:00
Mike Travis
7eb1955336 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask
Conflicts:
	arch/x86/kernel/io_apic.c
	kernel/rcuclassic.c
	kernel/sched.c
	kernel/time/tick-sched.c

Signed-off-by: Mike Travis <travis@sgi.com>
[ mingo@elte.hu: backmerged typo fix for io_apic.c ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-03 18:53:31 +01:00
Darren Hart
90621c40cc futex: catch certain assymetric (get|put)_futex_key calls
Impact: add debug check

Following up on my previous key reference accounting patches, this patch
will catch puts on keys that haven't been "got".  This won't catch nested
get/put mismatches though.

Build and boot tested, with minimal desktop activity and a run of the
open_posix_testsuite in LTP for testing.  No warnings logged.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-02 23:10:44 +01:00
Linus Torvalds
b840d79631 Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
  x86: export vector_used_by_percpu_irq
  x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
  sched: nominate preferred wakeup cpu, fix
  x86: fix lguest used_vectors breakage, -v2
  x86: fix warning in arch/x86/kernel/io_apic.c
  sched: fix warning in kernel/sched.c
  sched: move test_sd_parent() to an SMP section of sched.h
  sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
  sched: activate active load balancing in new idle cpus
  sched: bias task wakeups to preferred semi-idle packages
  sched: nominate preferred wakeup cpu
  sched: favour lower logical cpu number for sched_mc balance
  sched: framework for sched_mc/smt_power_savings=N
  sched: convert BALANCE_FOR_xx_POWER to inline functions
  x86: use possible_cpus=NUM to extend the possible cpus allowed
  x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
  x86: update io_apic.c to the new cpumask code
  x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
  x86: xen: use smp_call_function_many()
  x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
  ...

Fixed up trivial conflict in kernel/time/tick-sched.c manually
2009-01-02 11:44:09 -08:00
Mike Galbraith
0a582440ff sched: fix sched_slice()
Impact: fix bad-interactivity buglet

Fix sched_slice() to emit a sane result whether a task is currently
enqueued or not.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Tested-by: Jayson King <dev@jaysonking.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 kernel/sched_fair.c |   30 ++++++++++++------------------
 1 file changed, 12 insertions(+), 18 deletions(-)
2009-01-02 17:10:43 +01:00
Rusty Russell
5db0e1e9e0 cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
Impact: cleanup

Simple replacement, now the _nr is redundant.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
2009-01-01 10:12:29 +10:30
Rusty Russell
41c7bb9588 cpumask: convert rest of files in kernel/
Impact: Reduce stack usage, use new cpumask API.

Mainly changing cpumask_t to 'struct cpumask' and similar simple API
conversion.  Two conversions worth mentioning:

1) we use cpumask_any_but to avoid a temporary in kernel/softlockup.c,
2) Use cpumask_var_t in taskstats_user_cmd().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
2009-01-01 10:12:28 +10:30
Rusty Russell
e0b582ec56 cpumask: convert kernel/cpu.c
Impact: Reduce kernel stack and memory usage, use new cpumask API.

Use cpumask_var_t for take_cpu_down() stack var, and frozen_cpus.

Note that notify_cpu_starting() can be called before core_initcall
allocates frozen_cpus, but the NULL check is optimized out by gcc for
the CONFIG_CPUMASK_OFFSTACK=n case.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:28 +10:30
Rusty Russell
c309b917ca cpumask: convert kernel/profile.c
Impact: Reduce kernel memory usage, use new cpumask API.

Avoid a static cpumask_t for prof_cpu_mask, and an on-stack cpumask_t
in prof_cpu_mask_write_proc.  Both become cpumask_var_t.

prof_cpu_mask is only allocated when profiling is on, but the NULL
checks are optimized out by gcc for the !CPUMASK_OFFSTACK case.

Also removed some strange and unnecessary casts.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:27 +10:30
Rusty Russell
bd232f97b3 cpumask: convert RCU implementations
Impact: use new cpumask API.

rcu_ctrlblk contains a cpumask, and it's highly optimized so I don't want
a cpumask_var_t (ie. a pointer) for the CONFIG_CPUMASK_OFFSTACK case.  It
could use a dangling bitmap, and be allocated in __rcu_init to save memory,
but for the moment we use a bitmap.

(Eventually 'struct cpumask' will be undefined for CONFIG_CPUMASK_OFFSTACK,
so we use a bitmap here to show we really mean it).

We remove on-stack cpumasks, using cpumask_var_t for
rcu_torture_shuffle_tasks() and for_each_cpu_and in force_quiescent_state().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:26 +10:30
Rusty Russell
d036e67b40 cpumask: convert kernel/irq
Impact: Reduce stack usage, use new cpumask API.  ALPHA mod!

Main change is that irq_default_affinity becomes a cpumask_var_t, so
treat it as a pointer (this effects alpha).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:26 +10:30
Rusty Russell
6b954823c2 cpumask: convert kernel time functions
Impact: Use new APIs

Convert kernel/time functions to use struct cpumask *.

Note the ugly bitmap declarations in tick-broadcast.c.  These should
be cpumask_var_t, but there was no obvious initialization function to
put the alloc_cpumask_var() calls in.  This was safe.

(Eventually 'struct cpumask' will be undefined for CONFIG_CPUMASK_OFFSTACK,
so we use a bitmap here to show we really mean it).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-01 10:12:25 +10:30
Rusty Russell
e7577c50f2 cpumask: convert kernel/workqueue.c
Impact: Reduce memory usage, use new cpumask API.

cpu_populated_map becomes a cpumask_var_t, and cpu_singlethread_map is
simply a cpumask pointer: it's simply the cpumask containing the first
possible CPU anyway.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:25 +10:30
Rusty Russell
a45185d2d7 cpumask: convert kernel/compat.c
Impact: Reduce stack usage, use new cpumask API.

Straightforward conversion; cpumasks' size is given by cpumask_size() (now
a variable rather than fixed) and on-stack cpu masks use cpumask_var_t.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:24 +10:30
Rusty Russell
f1fc057c79 cpumask: remove any_online_cpu() users: kernel/
Impact: Remove obsolete API usage

any_online_cpu() is a good name, but it takes a cpumask_t, not a
pointer.

There are several places where any_online_cpu() doesn't really want a
mask arg at all.  Replace all callers with cpumask_any() and
cpumask_any_and().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-01 10:12:23 +10:30
Rusty Russell
4462344ee9 cpumask: convert kernel trace functions further
Impact: Reduce future memory usage, use new cpumask API.

Since the last patch was created and acked, more old cpumask users
slipped into kernel/trace.

Mostly trivial conversions, except struct trace_iterator's "started"
member becomes a cpumask_var_t.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:23 +10:30
Rusty Russell
9e01c1b74c cpumask: convert kernel trace functions
Impact: Reduce future memory usage, use new cpumask API.

(Eventually, cpumask_var_t will be allocated based on nr_cpu_ids, not NR_CPUS).

Convert kernel trace functions to use struct cpumask API:
1) Use cpumask_copy/cpumask_test_cpu/for_each_cpu.
2) Use cpumask_var_t and alloc_cpumask_var/free_cpumask_var everywhere.
3) Use on_each_cpu instead of playing with current->cpus_allowed.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
2009-01-01 10:12:22 +10:30
Rusty Russell
4f4b6c1a94 cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core
Impact: cleanup

In future, all cpumask ops will only be valid (in general) for bit
numbers < nr_cpu_ids.  So use that instead of NR_CPUS in iterators
and other comparisons.

This is always safe: no cpu number can be >= nr_cpu_ids, and
nr_cpu_ids is initialized to NR_CPUS at boot.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: James Morris <jmorris@namei.org>
Cc: Eric Biederman <ebiederm@xmission.com>
2009-01-01 10:12:15 +10:30
Linus Torvalds
db200df0b3 Merge branch 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sparseirq: move __weak symbols into separate compilation unit
  sparseirq: work around __weak alias bug
  sparseirq: fix hang with !SPARSE_IRQ
  sparseirq: set lock_class for legacy irq when sparse_irq is selected
  sparseirq: work around compiler optimizing away __weak functions
  sparseirq: fix desc->lock init
  sparseirq: do not printk when migrating IRQ descriptors
  sparseirq: remove duplicated arch_early_irq_init()
  irq: simplify for_each_irq_desc() usage
  proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
  irq: for_each_irq_desc() move to irqnr.h
  hrtimer: remove #include <linux/irq.h>
2008-12-31 09:00:59 -08:00
Martin Schwidefsky
79741dd357 [PATCH] idle cputime accounting
The cpu time spent by the idle process actually doing something is
currently accounted as idle time. This is plain wrong, the architectures
that support VIRT_CPU_ACCOUNTING=y can do better: distinguish between the
time spent doing nothing and the time spent by idle doing work. The first
is accounted with account_idle_time and the second with account_system_time.
The architectures that use the account_xxx_time interface directly and not
the account_xxx_ticks interface now need to do the check for the idle
process in their arch code. In particular to improve the system vs true
idle time accounting the arch code needs to measure the true idle time
instead of just testing for the idle process.
To improve the tick based accounting as well we would need an architecture
primitive that can tell us if the pt_regs of the interrupted context
points to the magic instruction that halts the cpu.

In addition idle time is no more added to the stime of the idle process.
This field now contains the system time of the idle process as it should
be. On systems without VIRT_CPU_ACCOUNTING this will always be zero as
every tick that occurs while idle is running will be accounted as idle
time.

This patch contains the necessary common code changes to be able to
distinguish idle system time and true idle time. The architectures with
support for VIRT_CPU_ACCOUNTING need some changes to exploit this.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31 15:11:46 +01:00
Martin Schwidefsky
457533a7d3 [PATCH] fix scaled & unscaled cputime accounting
The utimescaled / stimescaled fields in the task structure and the
global cpustat should be set on all architectures. On s390 the calls
to account_user_time_scaled and account_system_time_scaled never have
been added. In addition system time that is accounted as guest time
to the user time of a process is accounted to the scaled system time
instead of the scaled user time.
To fix the bugs and to prevent future forgetfulness this patch merges
account_system_time_scaled into account_system_time and
account_user_time_scaled into account_user_time.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Michael Neuling <mikey@neuling.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31 15:11:46 +01:00
Rusty Russell
2ca1a61583 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	arch/x86/kernel/io_apic.c
2008-12-31 23:05:57 +10:30
Thomas Gleixner
1c5745aa38 sched_clock: prevent scd->clock from moving backwards, take #2
Redo:

  5b7dba4: sched_clock: prevent scd->clock from moving backwards

which had to be reverted due to s2ram hangs:

  ca7e716: Revert "sched_clock: prevent scd->clock from moving backwards"

... this time with resume restoring GTOD later in the sequence
taken into account as well.

The "timekeeping_suspended" flag is not very nice but we cannot call into
GTOD before it has been properly resumed and the scheduler will run very
early in the resume sequence.

Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-31 09:53:21 +01:00
Linus Torvalds
6a94cb7306 Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (184 commits)
  [XFS] Fix race in xfs_write() between direct and buffered I/O with DMAPI
  [XFS] handle unaligned data in xfs_bmbt_disk_get_all
  [XFS] avoid memory allocations in xfs_fs_vcmn_err
  [XFS] Fix speculative allocation beyond eof
  [XFS] Remove XFS_BUF_SHUT() and friends
  [XFS] Use the incore inode size in xfs_file_readdir()
  [XFS] set b_error from bio error in xfs_buf_bio_end_io
  [XFS] use inode_change_ok for setattr permission checking
  [XFS] add a FMODE flag to make XFS invisible I/O less hacky
  [XFS] resync headers with libxfs
  [XFS] simplify projid check in xfs_rename
  [XFS] replace b_fspriv with b_mount
  [XFS] Remove unused tracing code
  [XFS] Remove unnecessary assertion
  [XFS] Remove unused variable in ktrace_free()
  [XFS] Check return value of xfs_buf_get_noaddr()
  [XFS] Fix hang after disallowed rename across directory quota domains
  [XFS] Fix compile with CONFIG_COMPAT enabled
  move inode tracing out of xfs_vnode.
  move vn_iowait / vn_iowake into xfs_aops.c
  ...
2008-12-30 17:48:25 -08:00
Huang Weiyi
1af237a099 tracing: removed duplicated #include
Removed duplicated #include in kernel/trace/trace.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-30 17:35:40 -08:00
Linus Torvalds
526ea064f9 Merge branch 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  oprofile: select RING_BUFFER
  ring_buffer: adding EXPORT_SYMBOLs
  oprofile: fix lost sample counter
  oprofile: remove nr_available_slots()
  oprofile: port to the new ring_buffer
  ring_buffer: add remaining cpu functions to ring_buffer.h
  oprofile: moving cpu_buffer_reset() to cpu_buffer.h
  oprofile: adding cpu_buffer_entries()
  oprofile: adding cpu_buffer_write_commit()
  oprofile: adding cpu buffer r/w access functions
  ftrace: remove unused function arg in trace_iterator_increment()
  ring_buffer: update description for ring_buffer_alloc()
  oprofile: set values to default when creating oprofilefs
  oprofile: implement switch/case in buffer_sync.c
  x86/oprofile: cleanup IBS init/exit functions in op_model_amd.c
  x86/oprofile: reordering IBS code in op_model_amd.c
  oprofile: fix typo
  oprofile: whitspace changes only
  oprofile: update comment for oprofile_add_sample()
  oprofile: comment cleanup
2008-12-30 17:31:25 -08:00
Linus Torvalds
6de71484cf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6: (98 commits)
  sparc: move select of ARCH_SUPPORTS_MSI
  sparc: drop SUN_IO
  sparc: unify sections.h
  sparc: use .data.init_task section for init_thread_union
  sparc: fix array overrun check in of_device_64.c
  sparc: unify module.c
  sparc64: prepare module_64.c for unification
  sparc64: use bit neutral Elf symbols
  sparc: unify module.h
  sparc: introduce CONFIG_BITS
  sparc: fix hardirq.h removal fallout
  sparc64: do not export pus_fs_struct
  sparc: use sparc64 version of scatterlist.h
  sparc: Commonize memcmp assembler.
  sparc: Unify strlen assembler.
  sparc: Add asm/asm.h
  sparc: Kill memcmp_32.S code which has been ifdef'd out for centuries.
  sparc: replace for_each_cpu_mask_nr with for_each_cpu
  sparc: fix sparse warnings in irq_32.c
  sparc: add include guards to kernel.h
  ...
2008-12-30 17:23:31 -08:00
Linus Torvalds
1dff81f20c Merge branch 'for-2.6.29' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.29' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  bio: get rid of bio_vec clearing
  bounce: don't rely on a zeroed bio_vec list
  cciss: simplify parameters to deregister_disk function
  cfq-iosched: fix race between exiting queue and exiting task
  loop: Do not call loop_unplug for not configured loop device.
  loop: Flush possible running bios when loop device is released.
  alpha: remove dead BIO_VMERGE_BOUNDARY
  Get rid of CONFIG_LSF
  block: make blk_softirq_init() static
  block: use min_not_zero in blk_queue_stack_limits
  block: add one-hit cache for disk partition lookup
  cfq-iosched: remove limit of dispatch depth of max 4 times quantum
  nbd: tell the block layer that it is not a rotational device
  block: get rid of elevator_t typedef
  aio: make the lookup_ioctx() lockless
  bio: add support for inlining a number of bio_vecs inside the bio
  bio: allow individual slabs in the bio_set
  bio: move the slab pointer inside the bio_set
  bio: only mempool back the largest bio_vec slab cache
  block: don't use plugging on SSD devices
  ...
2008-12-30 17:20:05 -08:00
Linus Torvalds
179475a3b4 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, sparseirq: clean up Kconfig entry
  x86: turn CONFIG_SPARSE_IRQ off by default
  sparseirq: fix numa_migrate_irq_desc dependency and comments
  sparseirq: add kernel-doc notation for new member in irq_desc, -v2
  locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEP
  sparseirq, xen: make sure irq_desc is allocated for interrupts
  sparseirq: fix !SMP building, #2
  x86, sparseirq: move irq_desc according to smp_affinity, v7
  proc: enclose desc variable of show_stat() in CONFIG_SPARSE_IRQ
  sparse irqs: add irqnr.h to the user headers list
  sparse irqs: handle !GENIRQ platforms
  sparseirq: fix !SMP && !PCI_MSI && !HT_IRQ build
  sparseirq: fix Alpha build failure
  sparseirq: fix typo in !CONFIG_IO_APIC case
  x86, MSI: pass irq_cfg and irq_desc
  x86: MSI start irq numbering from nr_irqs_gsi
  x86: use NR_IRQS_LEGACY
  sparse irq_desc[] array: core kernel and x86 changes
  genirq: record IRQ_LEVEL in irq_desc[]
  irq.h: remove padding from irq_desc on 64bits
2008-12-30 16:20:19 -08:00
Linus Torvalds
bb758e9637 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimers: fix warning in kernel/hrtimer.c
  x86: make sure we really have an hpet mapping before using it
  x86: enable HPET on Fujitsu u9200
  linux/timex.h: cleanup for userspace
  posix-timers: simplify de_thread()->exit_itimers() path
  posix-timers: check ->it_signal instead of ->it_pid to validate the timer
  posix-timers: use "struct pid*" instead of "struct task_struct*"
  nohz: suppress needless timer reprogramming
  clocksource, acpi_pm.c: put acpi_pm_read_slow() under CONFIG_PCI
  nohz: no softirq pending warnings for offline cpus
  hrtimer: removing all ur callback modes, fix
  hrtimer: removing all ur callback modes, fix hotplug
  hrtimer: removing all ur callback modes
  x86: correct link to HPET timer specification
  rtc-cmos: export second NVRAM bank

Fixed up conflicts in sound/drivers/pcsp/pcsp.c and sound/core/hrtimer.c
manually.
2008-12-30 16:16:21 -08:00
Linus Torvalds
5f34fe1cfc Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (63 commits)
  stacktrace: provide save_stack_trace_tsk() weak alias
  rcu: provide RCU options on non-preempt architectures too
  printk: fix discarding message when recursion_bug
  futex: clean up futex_(un)lock_pi fault handling
  "Tree RCU": scalable classic RCU implementation
  futex: rename field in futex_q to clarify single waiter semantics
  x86/swiotlb: add default swiotlb_arch_range_needs_mapping
  x86/swiotlb: add default phys<->bus conversion
  x86: unify pci iommu setup and allow swiotlb to compile for 32 bit
  x86: add swiotlb allocation functions
  swiotlb: consolidate swiotlb info message printing
  swiotlb: support bouncing of HighMem pages
  swiotlb: factor out copy to/from device
  swiotlb: add arch hook to force mapping
  swiotlb: allow architectures to override phys<->bus<->phys conversions
  swiotlb: add comment where we handle the overflow of a dma mask on 32 bit
  rcu: fix rcutorture behavior during reboot
  resources: skip sanity check of busy resources
  swiotlb: move some definitions to header
  swiotlb: allow architectures to override swiotlb pool allocation
  ...

Fix up trivial conflicts in
  arch/x86/kernel/Makefile
  arch/x86/mm/init_32.c
  include/linux/hardirq.h
as per Ingo's suggestions.
2008-12-30 16:10:19 -08:00
Darren Hart
42d35d48ce futex: make futex_(get|put)_key() calls symmetric
Impact: cleanup

This patch makes the calls to futex_get_key_refs() and futex_drop_key_refs()
explicitly symmetric by only "putting" keys we successfully "got".  Also
cleanup a couple return points that didn't "put" after a successful "get".

Build and boot tested on an x86_64 system.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-30 06:38:15 +01:00
Rusty Russell
ce47d974f7 cpumask: arch_send_call_function_ipi_mask: core
Impact: new API to reduce stack usage

We're weaning the core code off handing cpumask's around on-stack.
This introduces arch_send_call_function_ipi_mask().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:05:17 +10:30
Rusty Russell
54b11e6d57 cpumask: smp_call_function_many()
Impact: Implementation change to remove cpumask_t from stack.

Actually change smp_call_function_mask() to smp_call_function_many().
We avoid cpumasks on the stack in this version.

(S390 has its own version, but that's going away apparently).

We have to do some dancing to figure out if 0 or 1 other cpus are in
the mask supplied and the online mask without allocating a tmp
cpumask.  It's still fairly cheap.

We allocate the cpumask at the end of the call_function_data
structure: if allocation fails we fallback to smp_call_function_single
rather than using the baroque quiescing code (which needs a cpumask on
stack).

(Thanks to Hiroshi Shimamoto for spotting several bugs in previous versions!)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: npiggin@suse.de
Cc: axboe@kernel.dk
2008-12-30 09:05:16 +10:30
Rusty Russell
3fa4152069 cpumask: make set_cpu_*/init_cpu_* out-of-line
They're only for use in boot/cpu hotplug code anyway, and this avoids
the use of deprecated cpu_*_map.

Stephen Rothwell points out that gcc 4.2.4 (on powerpc at least)
didn't like the cast away of const anyway:

  include/linux/cpumask.h: In function 'set_cpu_possible':
  include/linux/cpumask.h:1052: warning: passing argument 2 of 'cpumask_set_cpu' discards qualifiers from pointer target type

So this kills two birds with one stone.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:05:16 +10:30
Rusty Russell
b3199c025d cpumask: switch over to cpu_online/possible/active/present_mask: core
Impact: cleanup

This implements the obsolescent cpu_online_map in terms of
cpu_online_mask, rather than the other way around.  Same for the other
maps.

The documentation comments are also updated to refer to _mask rather
than _map.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
2008-12-30 09:05:14 +10:30
Rusty Russell
33edcf133b Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-12-30 08:02:35 +10:30
Yinghai Lu
43a256322a sparseirq: move __weak symbols into separate compilation unit
GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

So move all the IRQ handling related __weak symbols to kernel/irq/chip.c.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29 12:15:49 +01:00
Jens Axboe
abf137dd77 aio: make the lookup_ioctx() lockless
The mm->ioctx_list is currently protected by a reader-writer lock,
so we always grab that lock on the read side for doing ioctx
lookups. As the workload is extremely reader biased, turn this into
an rcu hlist so we can make lookup_ioctx() lockless. Get rid of
the rwlock and use a spinlock for providing update side exclusion.

There's usually only 1 entry on this list, so it doesn't make sense
to look into fancier data structures.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:50 +01:00
Nikanth Karthikesan
7c0990c7ee Do not free io context when taking recursive faults in do_exit
When taking recursive faults in do_exit, if the io_context is not null,
exit_io_context() is being called. But it might decrement the refcount
more than once. It is better to leave this task alone.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:43 +01:00
Lachlan McIlroy
0a8c5395f9 [XFS] Fix merge failures
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

	fs/xfs/linux-2.6/xfs_cred.h
	fs/xfs/linux-2.6/xfs_globals.h
	fs/xfs/linux-2.6/xfs_ioctl.c
	fs/xfs/xfs_vnodeops.h

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-12-29 16:47:18 +11:00
David S. Miller
e3c6d4ee54 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
	arch/sparc64/kernel/idprom.c
2008-12-28 20:19:47 -08:00
Ingo Molnar
b2e2fe9962 sparseirq: work around __weak alias bug
Impact: fix boot crash if the kernel is built with certain GCC versions

GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

This can lead to the boot crash reported by Kamalesh Babulal:

 ACPI: Core revision 20080926
 Setting APIC routing to flat
 BUG: unable to handle kernel NULL pointer dereference at
 0000000000000000
 IP: [<ffffffff8021f9a8>] add_pin_to_irq_cpu+0x14/0x74
 PGD 0
 Oops: 0000 [#1] SMP
 [...]

So move the arch_init_chip_data() function from handle.c to manage.c.

Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29 00:19:55 +01:00
Linus Torvalds
96faec945f Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (25 commits)
  allow stripping of generated symbols under CONFIG_KALLSYMS_ALL
  kbuild: strip generated symbols from *.ko
  kbuild: simplify use of genksyms
  kernel-doc: check for extra kernel-doc notations
  kbuild: add headerdep used to detect inclusion cycles in header files
  kbuild: fix string equality testing in tags.sh
  kbuild: fix make tags/cscope
  kbuild: fix make incompatibility
  kbuild: remove TAR_IGNORE
  setlocalversion: add git-svn support
  setlocalversion: print correct subversion revision
  scripts: improve the decodecode script
  scripts/package: allow custom options to rpm
  genksyms: allow to ignore symbol checksum changes
  genksyms: track symbol checksum changes
  tags and cscope support really belongs in a shell script
  kconfig: fix options to check-lxdialog.sh
  kbuild: gen_init_cpio expands shell variables in file names
  remove bashisms from scripts/extract-ikconfig
  kbuild: teach mkmakfile to be silent
  ...
2008-12-28 15:13:48 -08:00
Linus Torvalds
a39b863342 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
  sched: fix warning in fs/proc/base.c
  schedstat: consolidate per-task cpu runtime stats
  sched: use RCU variant of list traversal in for_each_leaf_rt_rq()
  sched, cpuacct: export percpu cpuacct cgroup stats
  sched, cpuacct: refactoring cpuusage_read / cpuusage_write
  sched: optimize update_curr()
  sched: fix wakeup preemption clock
  sched: add missing arch_update_cpu_topology() call
  sched: let arch_update_cpu_topology indicate if topology changed
  sched: idle_balance() does not call load_balance_newidle()
  sched: fix sd_parent_degenerate on non-numa smp machine
  sched: add uid information to sched_debug for CONFIG_USER_SCHED
  sched: move double_unlock_balance() higher
  sched: update comment for move_task_off_dead_cpu
  sched: fix inconsistency when redistribute per-cpu tg->cfs_rq shares
  sched/rt: removed unneeded defintion
  sched: add hierarchical accounting to cpu accounting controller
  sched: include group statistics in /proc/sched_debug
  sched: rename SCHED_NO_NO_OMIT_FRAME_POINTER => SCHED_OMIT_FRAME_POINTER
  sched: clean up SCHED_CPUMASK_ALLOC
  ...
2008-12-28 12:27:58 -08:00
Linus Torvalds
b0f4b285d7 Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits)
  sched, trace: update trace_sched_wakeup()
  tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3
  Revert "x86: disable X86_PTRACE_BTS"
  ring-buffer: prevent false positive warning
  ring-buffer: fix dangling commit race
  ftrace: enable format arguments checking
  x86, bts: memory accounting
  x86, bts: add fork and exit handling
  ftrace: introduce tracing_reset_online_cpus() helper
  tracing: fix warnings in kernel/trace/trace_sched_switch.c
  tracing: fix warning in kernel/trace/trace.c
  tracing/ring-buffer: remove unused ring_buffer size
  trace: fix task state printout
  ftrace: add not to regex on filtering functions
  trace: better use of stack_trace_enabled for boot up code
  trace: add a way to enable or disable the stack tracer
  x86: entry_64 - introduce FTRACE_ frame macro v2
  tracing/ftrace: add the printk-msg-only option
  tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()
  x86, bts: correctly report invalid bts records
  ...

Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits
being already partly merged by the SH merge.
2008-12-28 12:21:10 -08:00
Yinghai Lu
12026ea16a sparseirq: fix hang with !SPARSE_IRQ
Impact: fix hang

Suresh report his two sockets system only works with SPARSE_IRQ enable
it turns out we miss the setting desc->irq

so provide early_irq_init() even !SPARSE_IRQ to set desc->irq

Reported-by: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27 17:52:07 +01:00
Yinghai Lu
fa6beb37b0 sparseirq: set lock_class for legacy irq when sparse_irq is selected
Impact: add lockdep annotation to legacy IRQ descs

Warnings resulting out of this were not seen in practice, but it's prudent
to initialize the legacy descriptors to the lock class as well, symmetric
to how we do it with other descriptors.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27 17:51:45 +01:00
Yinghai Lu
13a0c3c269 sparseirq: work around compiler optimizing away __weak functions
Impact: fix panic on null pointer with sparseirq

Some GCC versions seem to inline the weak global function,
when that function is empty.

Work it around, by making the functions return a (dummy) integer.

Signed-off-by: Yinghai <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27 13:24:00 +01:00
Ingo Molnar
793f7b12a0 sparseirq: fix desc->lock init
Impact: cleanup

init_one_irq_desc() does not initialize the desc->lock properly -
you cannot init a lock by memcpying some other lock on it.

This happens to work right now (because irq_desc_init is never in use),
but it's a dangerous construct nevertheless, so fix it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27 09:29:22 +01:00
Ingo Molnar
8b07cd4451 sparseirq: do not printk when migrating IRQ descriptors
Impact: reduce printk noise

There were a couple of leftover KERN_DEBUG debugging printks, remove
them. Also clarify an error message.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27 09:29:21 +01:00
Rusty Russell
be4d638c15 cpumask: Replace cpu_coregroup_map with cpu_coregroup_mask
cpu_coregroup_map returned a cpumask_t: it's going away.

(Note, the sched part of this patch won't apply meaningfully to the
sched tree, but I'm posting it to show the goal).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
2008-12-26 22:23:43 +10:30
Yinghai Lu
00c2363487 sparseirq: remove duplicated arch_early_irq_init()
Impact: clean up

We already have a weak copy of this function in init/main.c

Signed-off-by: Yinghai <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26 10:43:30 +01:00
KOSAKI Motohiro
18eefedfe8 irq: simplify for_each_irq_desc() usage
Impact: cleanup

all for_each_irq_desc() usage point have !desc check.
then its check can move into for_each_irq_desc() macro.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26 09:48:18 +01:00
KOSAKI Motohiro
26ddd8d5ca proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
Impact: cleanup

irq_desc can be NULL when CONFIG_SPARSE_IRQ=y only.
therefore, NULL checking can move into kstat_irqs_cpu() of SPARSE_IRQ version.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: "Yinghai Lu" <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26 09:48:18 +01:00
KOSAKI Motohiro
f9af0e7091 irq: for_each_irq_desc() move to irqnr.h
Impact: cleanup

before CONFIG_SPARSE_IRQ age, for_each_irq_desc() sat in irqnr.h and
could be called from generic code.

CONFIG_SPARSE_IRQ breaks this assumption, but SPARSE_IRQ version
for_each_irq_desc() also can move into irqnr.h easily.

Also, this patch unifies CONFIG_SPARSE_IRQ and !CONFIG_SPARSE_IRQ
for_each_irq_desc().

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26 09:48:17 +01:00
KOSAKI Motohiro
51bc39f4ba hrtimer: remove #include <linux/irq.h>
Impact: cleanup

<linux/irq.h> can be removed and should be, because:

  - hrtimer doesn't use any irq feature.
  - <linux/irq.h> shouldn't be include from generic code.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26 09:48:16 +01:00
Ingo Molnar
32e8d18683 Merge branches 'timers/clocksource', 'timers/hpet', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/rtc' into timers/core 2008-12-25 18:02:25 +01:00
Ingo Molnar
860cf8894b Merge branches 'irq/sparseirq', 'irq/genirq' and 'irq/urgent'; commit 'v2.6.28' into irq/core 2008-12-25 16:27:54 +01:00
Ingo Molnar
6638101c11 Merge branches 'core/debugobjects', 'core/iommu', 'core/locking', 'core/printk', 'core/rcu', 'core/resources', 'core/softirq' and 'core/stacktrace' into core/core 2008-12-25 14:06:29 +01:00
Ingo Molnar
cc37d3d206 Merge branch 'core/futexes' into core/core 2008-12-25 13:54:14 +01:00
Ingo Molnar
b594deb0cc Merge branch 'core/debug' into core/core 2008-12-25 13:53:11 +01:00
Ingo Molnar
0b271ef452 Merge commit 'v2.6.28' into core/core 2008-12-25 13:51:46 +01:00
Ingo Molnar
4e202284e6 Merge branch 'sched/urgent'; commit 'v2.6.28' into sched/core 2008-12-25 13:42:23 +01:00
Ingo Molnar
5250d329e3 Merge branches 'tracing/ftrace', 'tracing/hw-branch-tracing' and 'tracing/ring-buffer'; commit 'v2.6.28' into tracing/core 2008-12-25 13:11:00 +01:00
Peter Zijlstra
468a15bb4c sched, trace: update trace_sched_wakeup()
Impact: extend the wakeup tracepoint with the info whether the wakeup was real

Add the information needed to distinguish 'real' wakeups from 'false'
wakeups.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-25 13:10:21 +01:00
Ingo Molnar
9212ddb5ea stacktrace: provide save_stack_trace_tsk() weak alias
Impact: build fix

Some architectures have not implemented save_stack_trace_tsk() yet:

  fs/built-in.o: In function `proc_pid_stack':
  base.c:(.text+0x3f140): undefined reference to `save_stack_trace_tsk'

So warn about that if the facility is used.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-25 11:44:43 +01:00
Ingo Molnar
12d79bafb7 rcu: provide RCU options on non-preempt architectures too
Impact: build fix

Some old architectures still do not use kernel/Kconfig.preempt, so the
moving of the RCU options there broke their build:

 In file included from /home/mingo/tip/include/linux/sem.h:81,
                 from /home/mingo/tip/include/linux/sched.h:69,
                 from /home/mingo/tip/arch/alpha/kernel/asm-offsets.c:9:
 /home/mingo/tip/include/linux/rcupdate.h:62:2: error: #error "Unknown RCU implementation specified to kernel configuration"

Move these options back to init/Kconfig, which every architecture
includes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-25 09:31:28 +01:00
James Morris
cbacc2c7f0 Merge branch 'next' into for-linus 2008-12-25 11:40:09 +11:00
Ingo Molnar
db8862eafe Merge branch 'linus' into tracing/hw-branch-tracing 2008-12-24 21:08:26 +01:00
Li Zefan
20ca9b3f4c cgroups: avoid accessing uninitialized data in failure path
If cgroup_get_rootdir() failed, free_cg_links() will be called in the
failure path, but tmp_cg_links hasn't been initialized at that time.

I introduced this bug in the 2.6.27 merge window.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-23 15:58:21 -08:00
Sharyathi Nagesh
e368d3a836 cgroups: suppress bogus warning messages
Remove spurious warning messages that are thrown onto the console during
cgroup operations.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Sharyathi Nagesh <sharyathi@in.ibm.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-23 15:58:21 -08:00
Vaidyanathan Srinivasan
36dffab679 sched: nominate preferred wakeup cpu, fix
Andrew Morton reported:

> kernel/sched.c: In function 'schedule':
> kernel/sched.c:3679: warning: 'active_balance' may be used uninitialized in this function
>
> This warning is correct - the code is buggy.

In sched.c load_balance_newidle, there's real potential use of
uninitialised variable - fix it.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-23 22:37:29 +01:00
Steven Rostedt
98db8df777 ring-buffer: prevent false positive warning
Impact: eliminate false WARN_ON message

If an interrupt goes off after the setting of the local variable
tail_page and before incrementing the write index of that page,
the interrupt could push the commit forward to the next page.

Later a check is made to see if interrupts pushed the buffer around
the entire ring buffer by comparing the next page to the last commited
page. This can produce a false positive if the interrupt had pushed
the commit page forward as stated above.

Thanks to Jiaying Zhang for finding this race.

Reported-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-23 18:45:26 +01:00
Steven Rostedt
a8ccf1d6f6 ring-buffer: fix dangling commit race
Impact: fix stuck trace-buffers

If an interrupt comes in during the rb_set_commit_to_write and
pushes the tail page forward just at the right time, the commit
updates will miss the adding of the interrupt data. This will
cause the commit pointer to cease from moving forward.

Thanks to Jiaying Zhang for finding this race.

Reported-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-23 18:45:25 +01:00
Lachlan McIlroy
27a0464a6c [XFS] Fix merge conflict in fs/xfs/xfs_rename.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

	fs/xfs/xfs_rename.c

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-12-22 17:34:26 +11:00
Thomas Gleixner
3d44cc3e01 Null pointer deref with hrtimer_try_to_cancel()
Impact: Prevent kernel crash with posix timer clockid CLOCK_MONOTONIC_RAW

commit 2d42244ae7 (clocksource:
introduce CLOCK_MONOTONIC_RAW) introduced a new clockid, which is only
available to read out the raw not NTP adjusted system time.

The above commit did not prevent that a posix timer can be created
with that clockid. The timer_create() syscall succeeds and initializes
the timer to a non existing hrtimer base. When the timer is deleted
either by timer_delete() or by the exit() cleanup the kernel crashes.

Prevent the creation of timers for CLOCK_MONOTONIC_RAW by setting the
posix clock function to no_timer_create which returns an error code.

Reported-and-tested-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-20 14:13:45 -08:00
Markus Metzger
bf53de907d x86, bts: add fork and exit handling
Impact: introduce new ptrace facility

Add arch_ptrace_untrace() function that is called when the tracer
detaches (either voluntarily or when the tracing task dies);
ptrace_disable() is only called on a voluntary detach.

Add ptrace_fork() and arch_ptrace_fork(). They are called when a
traced task is forked.

Clear DS and BTS related fields on fork.

Release DS resources and reclaim memory in ptrace_untrace(). This
releases resources already when the tracing task dies. We used to do
that when the traced task dies.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-20 09:15:46 +01:00
Yinghai Lu
b909895739 sparseirq: fix numa_migrate_irq_desc dependency and comments
Impact: reduce kconfig variable scope and clean up

Bartlomiej pointed out that the config dependencies and comments are not right.

update it depend to NUMA, and fix some comments

Reported-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 22:56:02 +01:00
Hiroshi Shimamoto
26cc271db7 printk: fix discarding message when recursion_bug
Impact: fix truncated recursion bug message printout

When recursion_bug is true, kernel discards original message because printk_buf
contains recursion_bug_msg with NULL terminator. The sizeof(recursion_bug_msg)
makes this, use strlen() to get correct length without NULL terminator.

Reported-by: Toshikazu Nakayama <nakayama.ts@ncos.nec.co.jp>
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 22:52:47 +01:00
Jan Beulich
9bb482476c allow stripping of generated symbols under CONFIG_KALLSYMS_ALL
Building upon parts of the module stripping patch, this patch
introduces similar stripping for vmlinux when CONFIG_KALLSYMS_ALL=y.
Using CONFIG_KALLSYMS_STRIP_GENERATED reduces the overhead of
CONFIG_KALLSYMS_ALL from 245k/310k to 65k/80k for the (i386/x86-64)
kernels I tested with.

The patch also does away with the need to special case the kallsyms-
internal symbols by making them available even in the first linking
stage.

While it is a generated file, the patch includes the changes to
scripts/genksyms/keywords.c_shipped, as I'm unsure what the procedure
here is.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-12-19 22:47:10 +01:00
Pekka J Enberg
213cc06079 ftrace: introduce tracing_reset_online_cpus() helper
Impact: cleanup

This patch factors out common code from multiple tracers into a
tracing_reset_online_cpus() function and converts the tracers to use it.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 16:29:34 +01:00
Rafael J. Wysocki
baa5835df1 Hibernate: Replace unnecessary evaluation of pfn_to_page()
Replace one evaluation of pfn_to_page() in copy_data_pages() with
the value of a local variable containing the right number already.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-19 04:40:35 -05:00
Rafael J. Wysocki
846705deb0 Hibernate: Take overlapping zones into account (rev. 2)
It has been requested to make hibernation work with memory
hotplugging enabled and for this purpose the hibernation code has to
be reworked to take the possible overlapping of zones into account.
Thus, rework the hibernation memory bitmaps code to prevent
duplication of PFNs from occuring and add checks to make sure that
one page frame will not be marked as saveable many times.

Additionally, use list.h lists instead of open-coded lists to
implement the memory bitmaps.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-19 04:40:35 -05:00
Rafael J. Wysocki
69643279a8 Hibernate: Do not oops on resume if image data are incorrect
During resume from hibernation using the userland interface image
data are being passed from the used space process to the kernel.
These data need not be valid, but currently the kernel sometimes
oopses if it gets invalid image data, which is wrong.  Make the
kernel return error codes to the user space in such cases.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-19 04:40:35 -05:00
Rafael J. Wysocki
3f4b0ef7f2 ACPI hibernate: Add a mechanism to save/restore ACPI NVS memory
According to the ACPI Specification 3.0b, Section 15.3.2,
"OSPM will call the _PTS control method some time before entering a
sleeping state, to allow the platform's AML code to update this
memory image before entering the sleeping state. After the system
awakes from an S4 state, OSPM will restore this memory area and call
the _WAK control method to enable the BIOS to reclaim its memory
image."  For this reason, implement a mechanism allowing us to save
the NVS memory during hibernation and to restore it during the
subsequent resume.

Based on a patch by Zhang Rui.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Cc: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-19 04:40:34 -05:00
Zhang Rui
3fe0313e6e Hibernate: Call platform_begin before swsusp_shrink_memory
Call platform_begin() before swsusp_shrink_memory() so that we can
always allocate enough memory to save the ACPI NVS region from
platform_begin().

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-12-19 04:40:34 -05:00
Ingo Molnar
30cd324e97 Merge branches 'tracing/ftrace', 'tracing/ring-buffer' and 'tracing/urgent' into tracing/core
Conflicts:
	include/linux/ftrace.h
2008-12-19 09:42:40 +01:00
Ingo Molnar
9924da434a sched: fix warning in kernel/sched.c
Impact: fix cpumask conversion bug

this warning:

  kernel/sched.c: In function ‘find_busiest_group’:
  kernel/sched.c:3429: warning: passing argument 1 of ‘__first_cpu’ from incompatible pointer type

shows that we forgot to convert a new patch to the new cpumask APIs.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:57 +01:00
Vaidyanathan Srinivasan
ad273b32e4 sched: activate active load balancing in new idle cpus
Impact: tweak task balancing to save power more agressively

Active load balancing is a process by which migration thread
is woken up on the target CPU in order to pull current
running task on another package into this newly idle
package.

This method is already in use with normal load_balance(),
this patch introduces this method to new idle cpus when
sched_mc is set to POWERSAVINGS_BALANCE_WAKEUP.

This logic provides effective consolidation of short running
daemon jobs in a almost idle system

The side effect of this patch may be ping-ponging of tasks
if the system is moderately utilised. May need to adjust the
iterations before triggering.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:54 +01:00
Vaidyanathan Srinivasan
7eb52dfa70 sched: bias task wakeups to preferred semi-idle packages
Impact: tweak task wakeup to save power more agressively

Preferred wakeup cpu (from a semi idle package) has been
nominated in find_busiest_group() in the previous patch.  Use
this information in sched_mc_preferred_wakeup_cpu in function
wake_idle() to bias task wakeups if the following conditions
are satisfied:

        - The present cpu that is trying to wakeup the process is
          idle and waking the target process on this cpu will
          potentially wakeup a completely idle package
        - The previous cpu on which the target process ran is
          also idle and hence selecting the previous cpu may
          wakeup a semi idle cpu package
        - The task being woken up is allowed to run in the
          nominated cpu (cpu affinity and restrictions)

Basically if both the current cpu and the previous cpu on
which the task ran is idle, select the nominated cpu from semi
idle cpu package for running the new task that is waking up.

Cache hotness is considered since the actual biasing happens
in wake_idle() only if the application is cache cold.

This technique will effectively move short running bursty jobs in
a mostly idle system.

Wakeup biasing for power savings gets automatically disabled if
system utilisation increases due to the fact that the probability
of finding both this_cpu and prev_cpu idle decreases.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:52 +01:00
Vaidyanathan Srinivasan
7a09b1a27b sched: nominate preferred wakeup cpu
Impact: extend load-balancing code (no change in behavior yet)

When the system utilisation is low and more cpus are idle,
then the process waking up from sleep should prefer to
wakeup an idle cpu from semi-idle cpu package (multi core
package) rather than a completely idle cpu package which
would waste power.

Use the sched_mc balance logic in find_busiest_group() to
nominate a preferred wakeup cpu.

This info can be stored in appropriate sched_domain, but
updating this info in all copies of sched_domain is not
practical.  Hence this information is stored in root_domain
struct which is one copy per partitioned sched domain.
The root_domain can be accessed from each cpu's runqueue
and there is one copy per partitioned sched domain.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:50 +01:00
Vaidyanathan Srinivasan
d5679bd119 sched: favour lower logical cpu number for sched_mc balance
Impact: change load-balancing direction to match that of irqbalanced

Just in case two groups have identical load, prefer to move load to lower
logical cpu number rather than the present logic of moving to higher logical
number.

find_busiest_group() tries to look for a group_leader that has spare capacity
to take more tasks and freeup an appropriate least loaded group.  Just in case
there is a tie and the load is equal, then the group with higher logical number
is favoured.  This conflicts with user space irqbalance daemon that will move
interrupts to lower logical number if the system utilisation is very low.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:48 +01:00
Gautham R Shenoy
afb8a9b70b sched: framework for sched_mc/smt_power_savings=N
Impact: extend range of /sys/devices/system/cpu/sched_mc_power_savings

Currently the sched_mc/smt_power_savings variable is a boolean,
which either enables or disables topology based power savings.
This patch extends the behaviour of the variable from boolean to
multivalued, such that based on the value, we decide how
aggressively do we want to perform powersavings balance at
appropriate sched domain based on topology.

Variable levels of power saving tunable would benefit end user to
match the required level of power savings vs performance
trade-off depending on the system configuration and workloads.

This version makes the sched_mc_power_savings global variable to
take more values (0,1,2).  Later versions can have a single
tunable called sched_power_savings instead of
sched_{mc,smt}_power_savings.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:21:46 +01:00
Darren Hart
b56863630d futex: clean up futex_(un)lock_pi fault handling
Impact: cleanup

Some apparently left over cruft code was complicating the fault logic:

Testing if uval != -EFAULT doesn't have any meaning, get_user() sets ret
to either 0 or -EFAULT, there's no need to compare uval, especially not
against EFAULT which it will never be.  This patch removes the superfluous
test and clarifies the comment blocks.

Build and boot tested on an 8way x86_64 system.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 09:20:21 +01:00
Ingo Molnar
c71dd42db2 tracing: fix warnings in kernel/trace/trace_sched_switch.c
these warnings:

  kernel/trace/trace_sched_switch.c: In function ‘tracing_sched_register’:
  kernel/trace/trace_sched_switch.c:96: warning: passing argument 1 of ‘register_trace_sched_wakeup_new’ from incompatible pointer type
  kernel/trace/trace_sched_switch.c:112: warning: passing argument 1 of ‘unregister_trace_sched_wakeup_new’ from incompatible pointer type
  kernel/trace/trace_sched_switch.c: In function ‘tracing_sched_unregister’:
  kernel/trace/trace_sched_switch.c:121: warning: passing argument 1 of ‘unregister_trace_sched_wakeup_new’ from incompatible pointer type

Trigger because sched_wakeup_new tracepoints need the same trace
signature as sched_wakeup - which was changed recently.

Fix it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 01:05:38 +01:00
Ingo Molnar
3bddb9a324 tracing: fix warning in kernel/trace/trace.c
this warning:

  kernel/trace/trace.c: In function ‘print_lat_fmt’:
  kernel/trace/trace.c:1826: warning: unused variable ‘state’

Triggers because 'state' has become unused - remove it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 01:01:25 +01:00
Ingo Molnar
b2e3c0adec hrtimers: fix warning in kernel/hrtimer.c
this warning:

  kernel/hrtimer.c: In function ‘hrtimer_cpu_notify’:
  kernel/hrtimer.c:1574: warning: unused variable ‘dcpu’

is caused because 'dcpu' is only used in the CONFIG_HOTPLUG_CPU case.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 00:45:32 +01:00
Paul E. McKenney
64db4cfff9 "Tree RCU": scalable classic RCU implementation
This patch fixes a long-standing performance bug in classic RCU that
results in massive internal-to-RCU lock contention on systems with
more than a few hundred CPUs.  Although this patch creates a separate
flavor of RCU for ease of review and patch maintenance, it is intended
to replace classic RCU.

This patch still handles stress better than does mainline, so I am still
calling it ready for inclusion.  This patch is against the -tip tree.
Nevertheless, experience on an actual 1000+ CPU machine would still be
most welcome.

Most of the changes noted below were found while creating an rcutiny
(which should permit ejecting the current rcuclassic) and while doing
detailed line-by-line documentation.

Updates from v9 (http://lkml.org/lkml/2008/12/2/334):

o	Fixes from remainder of line-by-line code walkthrough,
	including comment spelling, initialization, undesirable
	narrowing due to type conversion, removing redundant memory
	barriers, removing redundant local-variable initialization,
	and removing redundant local variables.

	I do not believe that any of these fixes address the CPU-hotplug
	issues that Andi Kleen was seeing, but please do give it a whirl
	in case the machine is smarter than I am.

	A writeup from the walkthrough may be found at the following
	URL, in case you are suffering from terminal insomnia or
	masochism:

	http://www.kernel.org/pub/linux/kernel/people/paulmck/tmp/rcutree-walkthrough.2008.12.16a.pdf

o	Made rcutree tracing use seq_file, as suggested some time
	ago by Lai Jiangshan.

o	Added a .csv variant of the rcudata debugfs trace file, to allow
	people having thousands of CPUs to drop the data into
	a spreadsheet.	Tested with oocalc and gnumeric.  Updated
	documentation to suit.

Updates from v8 (http://lkml.org/lkml/2008/11/15/139):

o	Fix a theoretical race between grace-period initialization and
	force_quiescent_state() that could occur if more than three
	jiffies were required to carry out the grace-period
	initialization.  Which it might, if you had enough CPUs.

o	Apply Ingo's printk-standardization patch.

o	Substitute local variables for repeated accesses to global
	variables.

o	Fix comment misspellings and redundant (but harmless) increments
	of ->n_rcu_pending (this latter after having explicitly added it).

o	Apply checkpatch fixes.

Updates from v7 (http://lkml.org/lkml/2008/10/10/291):

o	Fixed a number of problems noted by Gautham Shenoy, including
	the cpu-stall-detection bug that he was having difficulty
	convincing me was real.  ;-)

o	Changed cpu-stall detection to wait for ten seconds rather than
	three in order to reduce false positive, as suggested by Ingo
	Molnar.

o	Produced a design document (http://lwn.net/Articles/305782/).
	The act of writing this document uncovered a number of both
	theoretical and "here and now" bugs as noted below.

o	Fix dynticks_nesting accounting confusion, simplify WARN_ON()
	condition, fix kerneldoc comments, and add memory barriers
	in dynticks interface functions.

o	Add more data to tracing.

o	Remove unused "rcu_barrier" field from rcu_data structure.

o	Count calls to rcu_pending() from scheduling-clock interrupt
	to use as a surrogate timebase should jiffies stop counting.

o	Fix a theoretical race between force_quiescent_state() and
	grace-period initialization.  Yes, initialization does have to
	go on for some jiffies for this race to occur, but given enough
	CPUs...

Updates from v6 (http://lkml.org/lkml/2008/9/23/448):

o	Fix a number of checkpatch.pl complaints.

o	Apply review comments from Ingo Molnar and Lai Jiangshan
	on the stall-detection code.

o	Fix several bugs in !CONFIG_SMP builds.

o	Fix a misspelled config-parameter name so that RCU now announces
	at boot time if stall detection is configured.

o	Run tests on numerous combinations of configurations parameters,
	which after the fixes above, now build and run correctly.

Updates from v5 (http://lkml.org/lkml/2008/9/15/92, bad subject line):

o	Fix a compiler error in the !CONFIG_FANOUT_EXACT case (blew a
	changeset some time ago, and finally got around to retesting
	this option).

o	Fix some tracing bugs in rcupreempt that caused incorrect
	totals to be printed.

o	I now test with a more brutal random-selection online/offline
	script (attached).  Probably more brutal than it needs to be
	on the people reading it as well, but so it goes.

o	A number of optimizations and usability improvements:

	o	Make rcu_pending() ignore the grace-period timeout when
		there is no grace period in progress.

	o	Make force_quiescent_state() avoid going for a global
		lock in the case where there is no grace period in
		progress.

	o	Rearrange struct fields to improve struct layout.

	o	Make call_rcu() initiate a grace period if RCU was
		idle, rather than waiting for the next scheduling
		clock interrupt.

	o	Invoke rcu_irq_enter() and rcu_irq_exit() only when
		idle, as suggested by Andi Kleen.  I still don't
		completely trust this change, and might back it out.

	o	Make CONFIG_RCU_TRACE be the single config variable
		manipulated for all forms of RCU, instead of the prior
		confusion.

	o	Document tracing files and formats for both rcupreempt
		and rcutree.

Updates from v4 for those missing v5 given its bad subject line:

o	Separated dynticks interface so that NMIs and irqs call separate
	functions, greatly simplifying it.  In particular, this code
	no longer requires a proof of correctness.  ;-)

o	Separated dynticks state out into its own per-CPU structure,
	avoiding the duplicated accounting.

o	The case where a dynticks-idle CPU runs an irq handler that
	invokes call_rcu() is now correctly handled, forcing that CPU
	out of dynticks-idle mode.

o	Review comments have been applied (thank you all!!!).
	For but one example, fixed the dynticks-ordering issue that
	Manfred pointed out, saving me much debugging.  ;-)

o	Adjusted rcuclassic and rcupreempt to handle dynticks changes.

Attached is an updated patch to Classic RCU that applies a hierarchy,
greatly reducing the contention on the top-level lock for large machines.
This passes 10-hour concurrent rcutorture and online-offline testing on
128-CPU ppc64 without dynticks enabled, and exposes some timekeeping
bugs in presence of dynticks (exciting working on a system where
"sleep 1" hangs until interrupted...), which were fixed in the
2.6.27 kernel.  It is getting more reliable than mainline by some
measures, so the next version will be against -tip for inclusion.
See also Manfred Spraul's recent patches (or his earlier work from
2004 at http://marc.info/?l=linux-kernel&m=108546384711797&w=2).
We will converge onto a common patch in the fullness of time, but are
currently exploring different regions of the design space.  That said,
I have already gratefully stolen quite a few of Manfred's ideas.

This patch provides CONFIG_RCU_FANOUT, which controls the bushiness
of the RCU hierarchy.  Defaults to 32 on 32-bit machines and 64 on
64-bit machines.  If CONFIG_NR_CPUS is less than CONFIG_RCU_FANOUT,
there is no hierarchy.  By default, the RCU initialization code will
adjust CONFIG_RCU_FANOUT to balance the hierarchy, so strongly NUMA
architectures may choose to set CONFIG_RCU_FANOUT_EXACT to disable
this balancing, allowing the hierarchy to be exactly aligned to the
underlying hardware.  Up to two levels of hierarchy are permitted
(in addition to the root node), allowing up to 16,384 CPUs on 32-bit
systems and up to 262,144 CPUs on 64-bit systems.  I just know that I
am going to regret saying this, but this seems more than sufficient
for the foreseeable future.  (Some architectures might wish to set
CONFIG_RCU_FANOUT=4, which would limit such architectures to 64 CPUs.
If this becomes a real problem, additional levels can be added, but I
doubt that it will make a significant difference on real hardware.)

In the common case, a given CPU will manipulate its private rcu_data
structure and the rcu_node structure that it shares with its immediate
neighbors.  This can reduce both lock and memory contention by multiple
orders of magnitude, which should eliminate the need for the strange
manipulations that are reported to be required when running Linux on
very large systems.

Some shortcomings:

o	More bugs will probably surface as a result of an ongoing
	line-by-line code inspection.

	Patches will be provided as required.

o	There are probably hangs, rcutorture failures, &c.  Seems
	quite stable on a 128-CPU machine, but that is kind of small
	compared to 4096 CPUs.  However, seems to do better than
	mainline.

	Patches will be provided as required.

o	The memory footprint of this version is several KB larger
	than rcuclassic.

	A separate UP-only rcutiny patch will be provided, which will
	reduce the memory footprint significantly, even compared
	to the old rcuclassic.  One such patch passes light testing,
	and has a memory footprint smaller even than rcuclassic.
	Initial reaction from various embedded guys was "it is not
	worth it", so am putting it aside.

Credits:

o	Manfred Spraul for ideas, review comments, and bugs spotted,
	as well as some good friendly competition.  ;-)

o	Josh Triplett, Ingo Molnar, Peter Zijlstra, Mathieu Desnoyers,
	Lai Jiangshan, Andi Kleen, Andy Whitcroft, and Andrew Morton
	for reviews and comments.

o	Thomas Gleixner for much-needed help with some timer issues
	(see patches below).

o	Jon M. Tollefson, Tim Pepper, Andrew Theurer, Jose R. Santos,
	Andy Whitcroft, Darrick Wong, Nishanth Aravamudan, Anton
	Blanchard, Dave Kleikamp, and Nathan Lynch for keeping machines
	alive despite my heavy abuse^Wtesting.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 21:56:04 +01:00
Ingo Molnar
d110ec3a1e Merge branch 'linus' into core/rcu 2008-12-18 21:54:49 +01:00
KOSAKI Motohiro
74c8a61304 locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEP
Impact: simplify code

commit "08678b0: generic: sparse irqs: use irq_desc() [...]" introduced
the irq_desc_lock_class variable.

But it is used only if CONFIG_SPARSE_IRQ=Y or CONFIG_TRACE_IRQFLAGS=Y.
Otherwise, following warnings happen:

	CC      kernel/irq/handle.o
	kernel/irq/handle.c:26: warning: 'irq_desc_lock_class' defined but not used

Actually, current early_init_irq_lock_class has a bit strange and messy ifdef.
In addition, it is not valueable.

1. this function is protected by !CONFIG_SPARSE_IRQ, but that is not necessary.
   if CONFIG_SPARSE_IRQ=Y, desc of all irq number are initialized by NULL
   at first - then this function calling is safe.

2. this function protected by CONFIG_TRACE_IRQFLAGS too. but it is not
   necessary either, because lockdep_set_class() doesn't have bad side
   effect even if CONFIG_TRACE_IRQFLAGS=n.

This patch bloat kernel size a bit on CONFIG_TRACE_IRQFLAGS=n and
CONFIG_SPARSE_IRQ=Y - but that's ok. early_init_irq_lock_class() is not
a fastpatch at all.

To avoid messy ifdefs is more important than a few bytes diet.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 14:35:53 +01:00
Ken Chen
9c2c48020e schedstat: consolidate per-task cpu runtime stats
Impact: simplify code

When we turn on CONFIG_SCHEDSTATS, per-task cpu runtime is accumulated
twice. Once in task->se.sum_exec_runtime and once in sched_info.cpu_time.
These two stats are exactly the same.

Given that task->se.sum_exec_runtime is always accumulated by the core
scheduler, sched_info can reuse that data instead of duplicate the accounting.

Signed-off-by: Ken Chen <kenchen@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 13:54:01 +01:00
Lai Jiangshan
6d102bc68f tracing/ring-buffer: remove unused ring_buffer size
Impact: remove dead code

struct ring_buffer.size is not set after ring_buffer is initialized
or resized. it is always 0.

we can use "buffer->pages * PAGE_SIZE" to get ring_buffer's size

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 13:49:56 +01:00
Thomas Gleixner
3d9101e925 trace: fix task state printout
Impact: fix occasionally incorrect trace output

The tracing code has interesting varieties of printing out task state.

Unfortunalely only one of the instances is correct as it copies the
code from sched.c:sched_show_task(). The others are plain wrong as
they treatthe bitfield as an integer offset into the character
array. Also the size check of the character array is wrong as it
includes the trailing \0.

Use a common state decoder inline which does the Right Thing.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 13:03:09 +01:00
Steven Rostedt
ea3a6d6d60 ftrace: add not to regex on filtering functions
Impact: enhancement

Ingo Molnar has asked about a way to remove items from the filter
lists. Currently, you can only add or replace items. The way
items are added to the list is through opening one of the list
files (set_ftrace_filter or set_ftrace_notrace) via append.
If the file is opened for truncate, the list is cleared.

  echo spin_lock > /debug/tracing/set_ftrace_filter

The above will replace the list with only spin_lock

  echo spin_lock >> /debug/tracing/set_ftrace_filter

The above will add spin_lock to the list.

Now this patch adds:

  echo '!spin_lock' >> /debug/tracing/set_ftrace_filter

This will remove spin_lock from the list.

The limited glob features of these lists also can be notted.

  echo '!spin_*' >> /debug/tracing/set_ftrace_filter

This will remove all functions that start with 'spin_'

Note:

  echo '!spin_*' > /debug/tracing/set_ftrace_filter

will simply clear out the list (notice the '>' instead of '>>')

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 12:57:09 +01:00
Steven Rostedt
e05a43b744 trace: better use of stack_trace_enabled for boot up code
Impact: clean up

Andrew Morton suggested to use the stack_tracer_enabled variable
to decide whether or not to start stack tracing on bootup.
This lets us remove the start_stack_trace variable.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 12:56:56 +01:00
Steven Rostedt
f38f1d2aa5 trace: add a way to enable or disable the stack tracer
Impact: enhancement to stack tracer

The stack tracer currently is either on when configured in or
off when it is not. It can not be disabled when it is configured on.
(besides disabling the function tracer that it uses)

This patch adds a way to enable or disable the stack tracer at
run time. It defaults off on bootup, but a kernel parameter 'stacktrace'
has been added to enable it on bootup.

A new sysctl has been added "kernel.stack_tracer_enabled" to let
the user enable or disable the stack tracer at run time.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 12:56:24 +01:00
Darren Hart
73500ac545 futex: rename field in futex_q to clarify single waiter semantics
Impact: simplify code

I've tripped over the naming of this field a couple times.

The futex_q uses a "waiters" list to represent a single blocked task and
then calles wake_up_all().

This can lead to confusion in trying to understand the intent of the code,
which is to have a single futex_q for every task waiting on a futex.

This patch corrects the problem, using a single pointer to the waiting
task, and an appropriate call to wake_up, rather than wake_up_all.

Compile and boot tested on an 8way x86_64 machine.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 11:42:23 +01:00
Ingo Molnar
948a7b2b5e Merge branch 'irq/sparseirq' into cpus4096
Conflicts:
	arch/x86/kernel/io_apic.c

Merge irq/sparseirq here, to resolve conflicts.
2008-12-17 13:16:08 +01:00
Ingo Molnar
1f3f424a6b Merge branch 'linus' into cpus4096 2008-12-17 13:07:48 +01:00
Frederic Weisbecker
66896a85cf tracing/ftrace: add the printk-msg-only option
Impact: display ftrace_printk messages "as is"

By default, ftrace_printk() messages find their output with some other
informations like pid, caller, ...
Sometimes a developer just want to have the ftrace_printk left "as is", without
other information.

This is done by providing a default-off option called printk-msg-only.
To enable it, just do `echo printk-msg-only > /debugfs/tracing/trace_options`

Before the patch:

           <...>-2739  [000]   145.692153: __might_sleep: I'm an ftrace_printk msg in __might_sleep
           <...>-2739  [000]   145.692155: __might_sleep: I'm another ftrace_printk msg in __might_sleep

After the patch and the printk-msg-only option enabled:

I'm an ftrace_printk msg in __might_sleep
I'm another ftrace_printk msg in __might_sleep

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-17 00:26:36 +01:00
Frederic Weisbecker
2c2d7329d8 tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()
Impact: prevent a trace recursion

After some tests with function graph tracer under x86-32, I saw some recursions
caused by ring_buffer_time_stamp() that calls preempt_enable_no_notrace() which
calls preempt_schedule() which is traced itself.

This patch re-enables preemption without rescheduling.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-17 00:26:35 +01:00
Yinghai Lu
48a1b10aff x86, sparseirq: move irq_desc according to smp_affinity, v7
Impact: improve NUMA handling by migrating irq_desc on smp_affinity changes

if CONFIG_NUMA_MIGRATE_IRQ_DESC is set:

-  make irq_desc to go with affinity aka irq_desc moving etc
-  call move_irq_desc in irq_complete_move()
-  legacy irq_desc is not moved, because they are allocated via static array

for logical apic mode, need to add move_desc_in_progress_in_same_domain,
otherwise it will not be moved ==> also could need two phases to get
irq_desc moved.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-17 00:14:01 +01:00
Paul E. McKenney
343e9099c8 rcu: fix rcutorture behavior during reboot
Impact: fix very rare reboot hang

Because rcutorture ignored all signals, it does not terminate in
response to the signals sent at shutdown time.  This can cause strange
failures due to its continuing to make use of kernel function too late
in the shutdown sequence.  This patch therefore adds a shutdown notifier
to rcutorture, causing it to shut down in response to a reboot or an
orderly shutdown.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-17 00:04:40 +01:00
Arjan van de Ven
3ac52669c7 resources: skip sanity check of busy resources
Impact: reduce false positives in iomem_map_sanity_check()

Some drivers (vesafb) only map/reserve a portion of a resource.
If then some other driver comes in and maps the whole resource,
the current code WARN_ON's. This is not the intent of the checks
in iomem_map_sanity_check(); rather these checks want to
warn when crossing *hardware* resources only.

This patch skips BUSY resources as suggested by Linus.

Note: having two drivers talk to the same hardware at the same
time is obviously not optimal behavior, but that's a separate story.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 23:30:49 +01:00
Bharata B Rao
80f40ee4a0 sched: use RCU variant of list traversal in for_each_leaf_rt_rq()
Impact: fix potential of rare crash

for_each_leaf_rt_rq() walks an RCU protected list (rq->leaf_rt_rq_list),
but doesn't use list_for_each_entry_rcu(). Fix this.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 21:39:14 +01:00
Ken Chen
e9515c3c9f sched, cpuacct: export percpu cpuacct cgroup stats
This patch export per-cpu CPU cycle usage for a given cpuacct cgroup.
There is a need for a user space monitor daemon to track group CPU
usage on per-cpu base.  It is also useful for monitoring CFS load
balancer behavior by tracking per CPU group usage.

Signed-off-by: Ken Chen <kenchen@google.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 12:15:01 +01:00
Ken Chen
720f54988e sched, cpuacct: refactoring cpuusage_read / cpuusage_write
Impact: micro-optimize the code on 64-bit architectures

In the thread regarding to 'export percpu cpuacct cgroup stats'
http://lkml.org/lkml/2008/12/7/13

akpm pointed out that current cpuacct code is inefficient.  This patch
refactoring the following:

* make cpu_rq locking only on 32-bit
* change iterator to each_present_cpu instead of each_possible_cpu to
  make it hotplug friendly.

It's a bit of code churn, but I was rewarded with 160 byte code size saving
on x86-64 arch and zero code size change on i386.

Signed-off-by: Ken Chen <kenchen@google.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 12:15:00 +01:00
Ingo Molnar
9dfc3bc7d2 Merge branches 'tracing/fastboot', 'tracing/ftrace', 'tracing/function-graph-tracer' and 'tracing/hw-branch-tracing' into tracing/core 2008-12-16 12:03:38 +01:00
Peter Zijlstra
34f28ecd0f sched: optimize update_curr()
Impact: micro-optimization

Skip the hard work when there is none.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 09:46:33 +01:00
Mike Galbraith
03e89e4574 sched: fix wakeup preemption clock
Impact: sharpen the wakeup-granularity to always be against current scheduler time

It was possible to do the preemption check against an old time stamp.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 09:45:38 +01:00
Paul Menage
307257cf47 cgroups: fix a race between rmdir and remount
When a cgroup is removed, it's unlinked from its parent's children list,
but not actually freed until the last dentry on it is released (at which
point cgrp->root->number_of_cgroups is decremented).

Currently rebind_subsystems checks for the top cgroup's child list being
empty in order to rebind subsystems into or out of a hierarchy - this can
result in the set of subsystems bound to a hierarchy being
removed-but-not-freed cgroup.

The simplest fix for this is to forbid remounts that change the set of
subsystems on a hierarchy that has removed-but-not-freed cgroups.  This
bug can be reproduced via:

mkdir /mnt/cg
mount -t cgroup -o ns,freezer cgroup /mnt/cg
mkdir /mnt/cg/foo
sleep 1h < /mnt/cg/foo &
rmdir /mnt/cg/foo
mount -t cgroup -o remount,ns,devices,freezer cgroup /mnt/cg
kill $!

Though the above will cause oops in -mm only but not mainline, but the bug
can cause memory leak in mainline (and even oops)

Signed-off-by: Paul Menage <menage@google.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-15 16:27:07 -08:00
Linus Torvalds
ca7e716c78 Revert "sched_clock: prevent scd->clock from moving backwards"
This reverts commit 5b7dba4ff8, which
caused a regression in hibernate, reported by and bisected by Fabio
Comolli.

This revert fixes

 http://bugzilla.kernel.org/show_bug.cgi?id=12155
 http://bugzilla.kernel.org/show_bug.cgi?id=12149

Bisected-by: Fabio Comolli <fabio.comolli@gmail.com>
Requested-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-14 16:23:17 -08:00
Rusty Russell
968ea6d80e Merge ../linux-2.6-x86
Conflicts:

	arch/x86/kernel/io_apic.c
	kernel/sched.c
	kernel/sched_stats.h
2008-12-13 21:55:51 +10:30
Rusty Russell
320ab2b0b1 cpumask: convert struct clock_event_device to cpumask pointers.
Impact: change calling convention of existing clock_event APIs

struct clock_event_timer's cpumask field gets changed to take pointer,
as does the ->broadcast function.

Another single-patch change.  For safety, we BUG_ON() in
clockevents_register_device() if it's not set.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
2008-12-13 21:20:26 +10:30
Rusty Russell
0de26520c7 cpumask: make irq_set_affinity() take a const struct cpumask
Impact: change existing irq_chip API

Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.

Fortunately, not widely used code, but hits a few architectures.

Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly.  Ingo, does this break anything?

(Folded in fix from KOSAKI Motohiro)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
2008-12-13 21:20:26 +10:30
Rusty Russell
29c0177e6a cpumask: change cpumask_scnprintf, cpumask_parse_user, cpulist_parse, and cpulist_scnprintf to take pointers.
Impact: change calling convention of existing cpumask APIs

Most cpumask functions started with cpus_: these have been replaced by
cpumask_ ones which take struct cpumask pointers as expected.

These four functions don't have good replacement names; fortunately
they're rarely used, so we just change them over.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: tony.luck@intel.com
Cc: ralf@linux-mips.org
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: cl@linux-foundation.org
Cc: srostedt@redhat.com
2008-12-13 21:20:25 +10:30
Rusty Russell
98a79d6a50 cpumask: centralize cpu_online_map and cpu_possible_map
Impact: cleanup

Each SMP arch defines these themselves.  Move them to a central
location.

Twists:
1) Some archs (m32, parisc, s390) set possible_map to all 1, so we add a
   CONFIG_INIT_ALL_POSSIBLE for this rather than break them.

2) mips and sparc32 '#define cpu_possible_map phys_cpu_present_map'.
   Those archs simply have phys_cpu_present_map replaced everywhere.

3) Alpha defined cpu_possible_map to cpu_present_map; this is tricky
   so I just manipulate them both in sync.

4) IA64, cris and m32r have gratuitous 'extern cpumask_t cpu_possible_map'
   declarations.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Mike Travis <travis@sgi.com>
Cc: ink@jurassic.park.msu.ru
Cc: rmk@arm.linux.org.uk
Cc: starvik@axis.com
Cc: tony.luck@intel.com
Cc: takata@linux-m32r.org
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: paulus@samba.org
Cc: schwidefsky@de.ibm.com
Cc: lethal@linux-sh.org
Cc: wli@holomorphy.com
Cc: davem@davemloft.net
Cc: jdike@addtoit.com
Cc: mingo@redhat.com
2008-12-13 21:19:41 +10:30
Oleg Nesterov
899921025b posix-timers: check ->it_signal instead of ->it_pid to validate the timer
Impact: clean up, speed up

->it_pid (was ->it_process) has also a special meaning: if it is NULL,
the timer is under deletion or it wasn't initialized yet. We can check
->it_signal != NULL instead, this way we can

	- simplify sys_timer_create() a bit

	- remove yet another check from lock_timer()

	- move put_pid(->it_pid) into release_posix_timer() which
	  runs outside of ->it_lock

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-12-12 17:00:34 +01:00
Oleg Nesterov
27af4245b6 posix-timers: use "struct pid*" instead of "struct task_struct*"
Impact: restructure, clean up code

k_itimer holds the ref to the ->it_process until sys_timer_delete(). This
allows to pin up to RLIMIT_SIGPENDING dead task_struct's. Change the code
to use "struct pid *" instead.

The patch doesn't kill ->it_process, it places ->it_pid into the union.
->it_process is still used by do_cpu_nanosleep() as before. It would be
trivial to change the nanosleep code as well, but since it uses it_process
in a special way I think it is better to keep this field for grep.

The patch bloats the kernel by 104 bytes and it also adds the new pointer,
->it_signal, to k_itimer. It is used by lock_timer() to verify that the
found timer was not created by another process. It is not clear why do we
use the global database (and thus the global idr_lock) for posix timers.
We still need the signal_struct->posix_timers which contains all useable
timers, perhaps it is better to use some form of per-process array
instead.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-12-12 17:00:07 +01:00
Woodruff, Richard
001474491f nohz: suppress needless timer reprogramming
In my device I get many interrupts from a high speed USB device in a very
short period of time.  The system spends a lot of time reprogramming the
hardware timer which is in a slower timing domain as compared to the CPU. 
This results in the CPU spending a huge amount of time waiting for the
timer posting to be done.  All of this reprogramming is useless as the
wake up time has not changed.

As measured using ETM trace this drops my reprogramming penalty from
almost 60% CPU load down to 15% during high interrupt rate.  I can send
traces to show this.

Suppress setting of duplicate timer event when timer already stopped. 
Timer programming can be very costly and can result in long cpu stall/wait
times.

[akpm@linux-foundation.org: coding-style fixes]
[tglx@linutronix.de: move the check to the right place and avoid raising
		     the softirq for nothing]

Signed-off-by: Richard Woodruff <r-woodruff2@ti.com>
Cc: johnstul@us.ibm.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-12-12 16:55:31 +01:00
Ingo Molnar
8299608f14 Merge branches 'irq/sparseirq', 'x86/quirks' and 'x86/reboot' into cpus4096
We merge the irq/sparseirq, x86/quirks and x86/reboot trees into the
cpus4096 tree because the io-apic changes in the sparseirq change
conflict with the cpumask changes in the cpumask tree, and we
want to resolve those.
2008-12-12 13:49:24 +01:00
Ingo Molnar
45ab6b0c76 Merge branch 'sched/core' into cpus4096
Conflicts:
	include/linux/ftrace.h
	kernel/sched.c
2008-12-12 13:48:57 +01:00
Heiko Carstens
d65bd5ecb2 sched: add missing arch_update_cpu_topology() call
arch_reinit_sched_domains() used to call arch_update_cpu_topology()
via arch_init_sched_domains(). This call got lost with
e761b77252 ("cpu hotplug, sched: Introduce
cpu_active_map and redo sched domain managment (take 2)".

So we might end up with outdated and missing cpus in the cpu core
maps (architecture used to call arch_reinit_sched_domains if cpu
topology changed).

This adds a call to arch_update_cpu_topology in partition_sched_domains
which gets called whenever scheduling domains get updated. Which is
what is supposed to happen when cpu topology changes.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 13:47:22 +01:00
Heiko Carstens
ee79d1bdb6 sched: let arch_update_cpu_topology indicate if topology changed
Change arch_update_cpu_topology so it returns 1 if the cpu topology changed
and 0 if it didn't change. This will be useful for the next patch which adds
a call to this function in partition_sched_domains.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 13:47:21 +01:00
Ingo Molnar
81444a7995 Merge branch 'tracing/fastboot' into cpus4096 2008-12-12 12:43:05 +01:00
Peter Zijlstra
cbc34ed1ac sched: fix tracepoints in scheduler
The trace point only caught one of many places where a task changes cpu,
put it in the right place to we get all of them.

Change the signature while we're at it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 12:08:26 +01:00
Frederic Weisbecker
f8b755ac8e tracing/function-graph-tracer: Output arrows signal on hardirq call/return
Impact: make more obvious the hardirq calls in the output

When a hardirq is triggered inside the codeflow on output, we have
now two arrows that indicate the entry and return of the hardirq.

 0)               |          bit_waitqueue() {
 0)   0.880 us    |            __phys_addr();
 0)   2.699 us    |          }
 0)               |          __wake_up_bit() {
 0)   ==========> |          smp_apic_timer_interrupt() {
 0)   0.797 us    |            native_apic_mem_write();
 0)   0.715 us    |            exit_idle();
 0)               |            irq_enter() {
 0)   0.722 us    |              idle_cpu();
 0)   5.519 us    |            }
 0)               |            hrtimer_interrupt() {
 0)               |              ktime_get() {
 0)               |                ktime_get_ts() {
 0)   0.805 us    |                  getnstimeofday();

 [...]

 0) ! 108.528 us  |            }
 0)               |            irq_exit() {
 0)               |              do_softirq() {
 0)               |                __do_softirq() {
 0)   0.895 us    |                  __local_bh_disable();
 0)               |                  run_timer_softirq() {
 0)   0.827 us    |                    hrtimer_run_pending();
 0)   1.226 us    |                    _spin_lock_irq();
 0)               |                    _spin_unlock_irq() {
 0)   6.550 us    |                  }
 0)   0.924 us    |                  _local_bh_enable();
 0) + 12.129 us   |                }
 0) + 13.911 us   |              }
 0)   0.707 us    |              idle_cpu();
 0) + 17.009 us   |            }
 0) ! 137.419 us  |          }
 0)   <========== |
 0)   1.045 us    |          }
 0) ! 148.908 us  |        }
 0) ! 151.022 us  |      }
 0) ! 153.022 us  |    }
 0)   0.963 us    |    journal_mark_dirty();
 0)   0.925 us    |    __brelse();

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 11:14:09 +01:00
Ingo Molnar
c1dfdc7597 Merge commit 'v2.6.28-rc8' into sched/core 2008-12-12 10:29:35 +01:00
Markus Metzger
a93751cab7 x86, bts, ftrace: adapt the hw-branch-tracer to the ds.c interface
Impact: restructure code, cleanup

Remove BTS bits from the hw-branch-tracer (renamed from bts-tracer) and
use the ds interface.

Signed-off-by: Markus Metzger <markut.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 08:08:14 +01:00
Heiko Carstens
fa116ea35e nohz: no softirq pending warnings for offline cpus
Impact: remove false positive warning

After a cpu was taken down during cpu hotplug (read: disabled for interrupts)
it still might have pending softirqs. However take_cpu_down makes sure
that the idle task will run next instead of ksoftirqd on the taken down cpu.
The idle task will call tick_nohz_stop_sched_tick which might warn about
pending softirqs just before the cpu kills itself completely.

However the pending softirqs on the dead cpu aren't a problem because they
will be moved to an online cpu during CPU_DEAD handling.

So make sure we warn only for online cpus.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 07:27:01 +01:00
Robert Richter
c4f50183f9 ring_buffer: adding EXPORT_SYMBOLs
I added EXPORT_SYMBOL_GPLs for all functions part of the API
(ring_buffer.h). This is required since oprofile is using the ring
buffer and the compilation as modules would fail otherwise.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 06:54:55 +01:00
Linus Torvalds
f9fc05e762 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: CPU remove deadlock fix
2008-12-10 14:41:06 -08:00
Hugh Dickins
b88ed20594 fix mapping_writably_mapped()
Lee Schermerhorn noticed yesterday that I broke the mapping_writably_mapped
test in 2.6.7!  Bad bad bug, good good find.

The i_mmap_writable count must be incremented for VM_SHARED (just as
i_writecount is for VM_DENYWRITE, but while holding the i_mmap_lock)
when dup_mmap() copies the vma for fork: it has its own more optimal
version of __vma_link_file(), and I missed this out.  So the count
was later going down to 0 (dangerous) when one end unmapped, then
wrapping negative (inefficient) when the other end unmapped.

The only impact on x86 would have been that setting a mandatory lock on
a file which has at some time been opened O_RDWR and mapped MAP_SHARED
(but not necessarily PROT_WRITE) across a fork, might fail with -EAGAIN
when it should succeed, or succeed when it should fail.

But those architectures which rely on flush_dcache_page() to flush
userspace modifications back into the page before the kernel reads it,
may in some cases have skipped the flush after such a fork - though any
repetitive test will soon wrap the count negative, in which case it will
flush_dcache_page() unnecessarily.

Fix would be a two-liner, but mapping variable added, and comment moved.

Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 14:40:45 -08:00
Hugh Dickins
9c24624727 KSYM_SYMBOL_LEN fixes
Miles Lane tailing /sys files hit a BUG which Pekka Enberg has tracked
to my 966c8c12dc sprint_symbol(): use
less stack exposing a bug in slub's list_locations() -
kallsyms_lookup() writes a 0 to namebuf[KSYM_NAME_LEN-1], but that was
beyond the end of page provided.

The 100 slop which list_locations() allows at end of page looks roughly
enough for all the other stuff it might print after the symbol before
it checks again: break out KSYM_SYMBOL_LEN earlier than before.

Latencytop and ftrace and are using KSYM_NAME_LEN buffers where they
need KSYM_SYMBOL_LEN buffers, and vmallocinfo a 2*KSYM_NAME_LEN buffer
where it wants a KSYM_SYMBOL_LEN buffer: fix those before anyone copies
them.

[akpm@linux-foundation.org: ftrace.h needs module.h]
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc Miles Lane <miles.lane@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:54 -08:00
Tom Zanussi
fbb5b7ae4b relayfs: fix infinite loop with splice()
Running kmemtraced, which uses splice() on relayfs, causes a hard lock on
x86-64 SMP.  As described by Tom Zanussi:

  It looks like you hit the same problem as described here:

  commit 8191ecd1d1

      splice: fix infinite loop in generic_file_splice_read()

  relay uses the same loop but it never got noticed or fixed.

Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Tested-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00