Commit Graph

2151 Commits

Author SHA1 Message Date
Benjamin Herrenschmidt
77c0a700c1 powerpc: Properly start decrementer on BookE secondary CPUs
This moves the code to start the decrementer on 40x and BookE into
a separate function which is now called from time_init() and
secondary_time_init(), before the respective clock sources are
registered. We also remove the 85xx specific code for doing it
from the platform code.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:25:04 +10:00
Kumar Gala
89c2dd62a3 powerpc/pci: Pull ppc32 PCI features into common
Some of the PCI features we have in ppc32 we will need on ppc64
platforms in the future.  These include support for:

* ppc_md.pci_exclude_device
* indirect config cycles
* early config cycles

We also simplified the logic in fake_pci_bus() to assume it will always
get a valid pci_controller.  Since all current callers seem to pass it
one.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:15 +10:00
Grant Likely
fbe6544719 powerpc/pci: move pci_64.c device tree scanning code into pci-common.c
The PCI device tree scanning code in pci_64.c is some useful functionality.
It allows PCI devices to be described in the device tree instead of being
probed for, which in turn allows pci devices to use all of the device tree
facilities to describe complex PCI bus architectures like GPIO and IRQ
routing (perhaps not a common situation for desktop or server systems,
but useful for embedded systems with on-board PCI devices).

This patch moves the device tree scanning into pci-common.c so it is
available for 32-bit powerpc machines too.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:15 +10:00
Grant Likely
ae14e13a4c powerpc/pci: Remove dead checks for CONFIG_PPC_OF
PPC_OF is always selected for arch/powerpc.  This patch removes the stale
#defines

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:14 +10:00
Kumar Gala
bb1af71ecb powerpc/book3e-64: Add support to initial_tlb_book3e for non-HES TLB
We now search through TLBnCFG looking for the first array that has IPROT
support (we assume that there is only one).  If that TLB has hardware
entry select (HES) support we use the existing code and with the proper
TLB select (the HES code still needs to clean up bolted entries from
firmware).  The non-HES code is pretty similiar to the 32-bit FSL Book-E
code but does make some new assumtions (like that we have tlbilx) and
simplifies things down a bit.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:14 +10:00
Kumar Gala
4b98d9e713 powerpc/book3e-64: Add helper function to setup IVORs
Not all 64-bit Book-3E parts will have fixed IVORs so add a function that
cpusetup code can call to setup the base IVORs (0..15) to match the fixed
offsets.  We need to 'or' part of interrupt_base_book3e into the IVORs
since on parts that have them the IVPR doesn't extend as far down.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:13 +10:00
Kumar Gala
6c188829d2 powerpc/book3e-64: Wait til generic_calibrate_decr to enable decrementer
Match what we do on 32-bit Book-E processors and enable the decrementer
in generic_calibrate_decr.  We need to make sure we disable the
decrementer early in boot since we currently use lazy (soft) interrupt
on 64-bit Book-E and possible get a decrementer exception before we
are ready for it.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:13 +10:00
Kumar Gala
f45c4486f7 powerpc/book3e-64: Move the default cpu table entry
Move the default cpu entry table for CONFIG_PPC_BOOK3E_64 to the
very end since we will probably want to support both 32-bit and
64-bit kernels for some processors that are higher up in the list.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:13 +10:00
FUJITA Tomonori
80d3e8abb7 powerpc: Add CONFIG_DMA_API_DEBUG support
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:11 +10:00
FUJITA Tomonori
4a9a6bfe70 powerpc: Handle SWIOTLB mapping error properly
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:11 +10:00
FUJITA Tomonori
45223c5492 powerpc: use dma_map_ops struct
This converts uses dma_map_ops struct (in include/linux/dma-mapping.h)
instead of POWERPC homegrown dma_mapping_ops.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:10 +10:00
FUJITA Tomonori
3702977fa7 powerpc: Remove swiotlb_pci_dma_ops
Now swiotlb_pci_dma_ops is identical to swiotlb_dma_ops; we can use
swiotlb_dma_ops with any devices. This removes swiotlb_pci_dma_ops.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:09 +10:00
FUJITA Tomonori
762afb7317 powerpc: Remove addr_needs_map in struct dma_mapping_ops
This patch adds max_direct_dma_addr to struct dev_archdata to remove
addr_needs_map in struct dma_mapping_ops. It also converts
dma_capable() to use max_direct_dma_addr.

max_direct_dma_addr is initialized in pci_dma_dev_setup_swiotlb(),
called via ppc_md.pci_dma_dev_setup hook.

For further information:
http://marc.info/?t=124719060200001&r=1&w=2

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-28 14:24:09 +10:00
Benjamin Herrenschmidt
2864697cef Merge commit 'tip/iommu-for-powerpc' into next 2009-08-28 14:23:06 +10:00
Gautham R Shenoy
6776426320 powerpc/pseries: Reduce the polling interval in __cpu_up()
Time time taken for a single cpu online operation on a pseries machine
is as follows:
Dedicated LPAR (POWER6): ~220ms.
Shared LPAR (POWER5)   : ~240ms.

Of this time, approximately 200ms is taken up by __cpu_up(). This is because
we poll every 200ms to check if the new cpu has notified it's presence
through the cpu_callin_map. We repeat this operation until the new cpu sets
the value in cpu_callin_map or 5 seconds elapse, whichever comes earlier.

However, using completion_structs instead of polling loops,
the time taken by the new processor to indicate it's presence has
found to be less than 1ms on pseries. This method however may not
work on all powerpc platforms due to the time-base synchronization code.

Keeping this in mind, we could reduce msleep polling interval from
200ms to 1ms while retaining the 5 second timeout.

With this, the time taken for a cpu online operation changes as follows:
Dedicated LPAR (POWER6): 20-25ms.
Shared LPAR (POWER5)   : 60-80ms.

In both these cases, it was found that the code polls through the loop
only once indicating that 1ms is a reasonable value, atleast on pseries.

The code needs testing on other powerpc platforms.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Acked-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:12:54 +10:00
Josh Boyer
14d757520a powerpc: Fix __flush_icache_range on 44x
The ptrace POKETEXT interface allows a process to modify the text pages of
a child process being ptraced, usually to insert breakpoints via trap
instructions.  The kernel eventually calls copy_to_user_page, which in turn
calls __flush_icache_range to invalidate the icache lines for the child
process.

However, this function does not work on 44x due to the icache being virtually
indexed.  This was noticed by a breakpoint being triggered after it had been
cleared by ltrace on a 440EPx board.  The convenient solution is to do a
flash invalidate of the icache in the __flush_icache_range function.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:12:52 +10:00
Benjamin Herrenschmidt
ea3cc330ac powerpc/mm: Cleanup handling of execute permission
This is an attempt at cleaning up a bit the way we handle execute
permission on powerpc. _PAGE_HWEXEC is gone, _PAGE_EXEC is now only
defined by CPUs that can do something with it, and the myriad of
#ifdef's in the I$/D$ coherency code is reduced to 2 cases that
hopefully should cover everything.

The logic on BookE is a little bit different than what it was though
not by much. Since now, _PAGE_EXEC will be set by the generic code
for executable pages, we need to filter out if they are unclean and
recover it. However, I don't expect the code to be more bloated than
it already was in that area due to that change.

I could boast that this brings proper enforcing of per-page execute
permissions to all BookE and 40x but in fact, we've had that now for
some time as a side effect of my previous rework in that area (and
I didn't even know it :-) We would only enable execute permission if
the page was cache clean and we would only cache clean it if we took
and exec fault. Since we now enforce that the later only work if
VM_EXEC is part of the VMA flags, we de-fact already enforce per-page
execute permissions... Unless I missed something

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:12:51 +10:00
Benjamin Herrenschmidt
4f0dbc2781 Merge commit 'paulus-perf/master' into next 2009-08-20 11:07:56 +10:00
Michael Ellerman
903444e429 powerpc/vmlinux.lds: Move _edata down
Currently _edata does not include several data sections, this causes
the kernel's report of memory usage at boot to not match reality, and
also prevents kmemleak from working - because it scan between _sdata
and _edata for pointers to allocated memory.

This mirrors a similar change made recently to the x86 linker script.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:29:29 +10:00
Michael Ellerman
a15098c90d powerpc: Enable GCOV
Make it possible to enable GCOV code coverage measurement on powerpc.

Lightly tested on 64-bit, seems to work as expected.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:29:28 +10:00
Julia Lawall
14ea58ad79 powerpc: Use DIV_ROUND_CLOSEST in time init code
The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression x,__divisor;
@@

- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:29:26 +10:00
Benjamin Krill
cf68787b68 powerpc/prom_init: Evaluate mem kernel parameter for early allocation
Evaluate mem kernel parameter for early memory allocations. If mem is set
no allocation in the region above the given boundary is allowed. The current
code doesn't take care about this and allocate memory above the given mem
boundary.

Signed-off-by: Benjamin Krill <ben@codiert.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:29:25 +10:00
Stefan Roese
20d70345f1 powerpc: Add AMCC 460EX/460GT Rev. B support to cputable.c
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:18 +10:00
Benjamin Herrenschmidt
2d27cfd328 powerpc: Remaining 64-bit Book3E support
This contains all the bits that didn't fit in previous patches :-) This
includes the actual exception handlers assembly, the changes to the
kernel entry, other misc bits and wiring it all up in Kconfig.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:11 +10:00
Benjamin Herrenschmidt
25d21ad6e7 powerpc: Add TLB management code for 64-bit Book3E
This adds the TLB miss handler assembly, the low level TLB flush routines
along with the necessary hook for dealing with our virtual page tables
or indirect TLB entries that need to be flushes when PTE pages are freed.

There is currently no support for hugetlbfs

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:09 +10:00
Benjamin Herrenschmidt
dce6670aaa powerpc: Add PACA fields specific to 64-bit Book3E processors
This adds various fields in the PACA that are for use specifically
by Book3E processors, such as exception save areas, current pgd
pointer, special exceptions kernel stacks etc...

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:08 +10:00
Benjamin Herrenschmidt
57e2a99f74 powerpc: Add memory management headers for new 64-bit BookE
This adds the PTE and pgtable format definitions, along with changes
to the kernel memory map and other definitions related to implementing
support for 64-bit Book3E. This also shields some asm-offset bits that
are currently only relevant on 32-bit

We also move the definition of the "linux" page size constants to
the common mmu.h file and add a few sizes that are relevant to
embedded processors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:06 +10:00
Benjamin Herrenschmidt
cf54dc7cd4 powerpc: Move definitions of secondary CPU spinloop to header file
Those definitions are currently declared extern in the .c file where
they are used, move them to a header file instead.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:44 +10:00
Benjamin Herrenschmidt
747bea91b7 powerpc: Clean ifdef usage in copy_thread()
Currently, a single ifdef covers SLB related bits and more generic ppc64
related bits, split this in two separate ifdef's since 64-bit BookE will
need one but not the other.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:43 +10:00
Benjamin Herrenschmidt
6f0ef0f505 powerpc/mm: Call mmu_context_init() from ppc64
Our 64-bit hash context handling has no init function, but 64-bit Book3E
will use the common mmu_context_nohash.c code which does, so define an
empty inline mmu_context_init() for 64-bit server and call it from
our 64-bit setup_arch()

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
2009-08-20 10:12:42 +10:00
Benjamin Herrenschmidt
6c1719942e powerpc/of: Remove useless register save/restore when calling OF back
enter_prom() used to save and restore registers such as CTR, XER etc..
which are volatile, or SRR0,1... which we don't care about. This
removes a bunch of useless code and while at it turns an mtmsrd into
an MTMSRD macro which will be useful to Book3E.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:36 +10:00
Benjamin Herrenschmidt
dd90bbd5fb powerpc: Add compat_sys_truncate
The truncate syscall has a signed long parameter, so when using a 32-
bit userspace with a 64-bit kernel the argument is zero-extended
instead of sign-extended. Adding the compat_sys_truncate function
fixes the issue.

This was noticed during an LSB truncate test failure. The test was
checking for the correct error number set when truncate is called with
a length of -1. The test can be found at:

http://bzr.linuxfoundation.org/lsb/devel/runtime-test?cmd=inventory;rev=stewb%40linux-foundation.org-20090626205411-sfb23cc0tjj7jzgm;path=modules/vsx-pcts/tset/POSIX.os/files/truncate/

BenH: Added compat_sys_ftruncate() as well, same issue.

Signed-off-by: Chase Douglas <cndougla@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:34 +10:00
Benjamin Herrenschmidt
c5a8c0c99f powerpc: Remove use of a second scratch SPRG in STAB code
The STAB code used on Power3 and RS/64 uses a second scratch SPRG to
save a GPR in order to decide whether to go to do_stab_bolted_* or
to handle a normal data access exception.

This prevents our scheme of freeing SPRG3 which is user visible for
user uses since we cannot use SPRG0 which, on RS/64, seems to be
read-only for supervisor mode (like POWER4).

This reworks the STAB exception entry to use the PACA as temporary
storage instead.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:28 +10:00
Benjamin Herrenschmidt
ee43eb788b powerpc: Use names rather than numbers for SPRGs (v2)
The kernel uses SPRG registers for various purposes, typically in
low level assembly code as scratch registers or to hold per-cpu
global infos such as the PACA or the current thread_info pointer.

We want to be able to easily shuffle the usage of those registers
as some implementations have specific constraints realted to some
of them, for example, some have userspace readable aliases, etc..
and the current choice isn't always the best.

This patch should not change any code generation, and replaces the
usage of SPRN_SPRGn everywhere in the kernel with a named replacement
and adds documentation next to the definition of the names as to
what those are used for on each processor family.

The only parts that still use the original numbers are bits of KVM
or suspend/resume code that just blindly needs to save/restore all
the SPRGs.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:27 +10:00
Benjamin Herrenschmidt
8aa34ab8b2 powerpc: Rename exception.h to exception-64s.h
The file include/asm/exception.h contains definitions
that are specific to exception handling on 64-bit server
type processors.

This renames the file to exception-64s.h to reflect that
fact and avoid confusion.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:26 +10:00
Anton Blanchard
30d0b36828 powerpc: Move 64bit VDSO to improve context switch performance
On 64bit applications the VDSO is the only thing in segment 0. Since the VDSO
is position independent we can remove the hint and let get_unmapped_area pick
an area. This will mean the vdso will be near other mmaps and will share
an SLB entry:

10000000-10001000 r-xp 00000000 08:06 5778459        /root/context_switch_64
10010000-10011000 r--p 00000000 08:06 5778459        /root/context_switch_64
10011000-10012000 rw-p 00001000 08:06 5778459        /root/context_switch_64
fffa92ae000-fffa92b0000 rw-p 00000000 00:00 0
fffa92b0000-fffa9453000 r-xp 00000000 08:06 4334051  /lib64/power6/libc-2.9.so
fffa9453000-fffa9462000 ---p 001a3000 08:06 4334051  /lib64/power6/libc-2.9.so
fffa9462000-fffa9466000 r--p 001a2000 08:06 4334051  /lib64/power6/libc-2.9.so
fffa9466000-fffa947c000 rw-p 001a6000 08:06 4334051  /lib64/power6/libc-2.9.so
fffa947c000-fffa9480000 rw-p 00000000 00:00 0
fffa9480000-fffa94a8000 r-xp 00000000 08:06 4333852  /lib64/ld-2.9.so
fffa94b3000-fffa94b4000 rw-p 00000000 00:00 0

fffa94b4000-fffa94b7000 r-xp 00000000 00:00 0        [vdso] <----- here I am

fffa94b7000-fffa94b8000 r--p 00027000 08:06 4333852  /lib64/ld-2.9.so
fffa94b8000-fffa94bb000 rw-p 00028000 08:06 4333852  /lib64/ld-2.9.so
fffa94bb000-fffa94bc000 rw-p 00000000 00:00 0
fffe4c10000-fffe4c25000 rw-p 00000000 00:00 0        [stack]

On a microbenchmark that bounces a token between two 64bit processes over pipes
and calls gettimeofday each iteration (to access the VDSO), our context switch
rate goes from 268k to 277k ctx switches/sec (tested on a 4GHz POWER6).

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:24 +10:00
Paul Mackerras
20002ded4d perf_counter: powerpc: Add callchain support
This adds support for tracing callchains for powerpc, both 32-bit
and 64-bit, and both in the kernel and userspace, from PMU interrupt
context.

The first three entries stored for each callchain are the NIP (next
instruction pointer), LR (link register), and the contents of the LR
save area in the second stack frame (the first is ignored because the
ABI convention on powerpc is that functions save their return address
in their caller's stack frame).  Because leaf functions don't have to
save their return address (LR value) and don't have to establish a
stack frame, it's possible for either or both of LR and the second
stack frame's LR save area to have valid return addresses in them.
This is basically impossible to disambiguate without either reading
the code or looking at auxiliary information such as CFI tables.
Since we don't want to do either of those things at interrupt time,
we store both LR and the second stack frame's LR save area.

Once we get past the second stack frame, there is no ambiguity; all
return addresses we get are reliable.

For kernel traces, we check whether they are valid kernel instruction
addresses and store zero instead if they are not (rather than
omitting them, which would make it impossible for userspace to know
which was which).  We also store zero instead of the second stack
frame's LR save area value if it is the same as LR.

For kernel traces, we check for interrupt frames, and for user traces,
we check for signal frames.  In each case, since we're starting a new
trace, we store a PERF_CONTEXT_KERNEL/USER marker so that userspace
knows that the next three entries are NIP, LR and the second stack frame
for the interrupted context.

We read user memory with __get_user_inatomic.  On 64-bit, if this
PMU interrupt occurred while interrupts are soft-disabled, and
there is no MMU hash table entry for the page, we will get an
-EFAULT return from __get_user_inatomic even if there is a valid
Linux PTE for the page, since hash_page isn't reentrant.  Thus we
have code here to read the Linux PTE and access the page via the
kernel linear mapping.  Since 64-bit doesn't use (or need) highmem
there is no need to do kmap_atomic.  On 32-bit, we don't do soft
interrupt disabling, so this complication doesn't occur and there
is no need to fall back to reading the Linux PTE, since hash_page
(or the TLB miss handler) will get called automatically if necessary.

Note that we cannot get PMU interrupts in the interval during
context switch between switch_mm (which switches the user address
space) and switch_to (which actually changes current to the new
process).  On 64-bit this is because interrupts are hard-disabled
in switch_mm and stay hard-disabled until they are soft-enabled
later, after switch_to has returned.  So there is no possibility
of trying to do a user stack trace when the user address space is
not current's address space.

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-18 14:48:47 +10:00
Paul Mackerras
9c1e105238 powerpc: Allow perf_counters to access user memory at interrupt time
This provides a mechanism to allow the perf_counters code to access
user memory in a PMU interrupt routine.  Such an access can cause
various kinds of interrupt: SLB miss, MMU hash table miss, segment
table miss, or TLB miss, depending on the processor.  This commit
only deals with 64-bit classic/server processors, which use an MMU
hash table.  32-bit processors are already able to access user memory
at interrupt time.  Since we don't soft-disable on 32-bit, we avoid
the possibility of reentering hash_page or the TLB miss handlers,
since they run with interrupts disabled.

On 64-bit processors, an SLB miss interrupt on a user address will
update the slb_cache and slb_cache_ptr fields in the paca.  This is
OK except in the case where a PMU interrupt occurs in switch_slb,
which also accesses those fields.  To prevent this, we hard-disable
interrupts in switch_slb.  Interrupts are already soft-disabled at
this point, and will get hard-enabled when they get soft-enabled
later.

This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice,
and to make sure that it clears the slb_cache_ptr when called from
other callers than switch_slb, the existing routine is renamed to
__slb_flush_and_rebolt, which is called by switch_slb and the new
version of slb_flush_and_rebolt.

Similarly, switch_stab (used on POWER3 and RS64 processors) gets a
hard_irq_disable() to protect the per-cpu variables used there and
in ste_allocate.

If a MMU hashtable miss interrupt occurs, normally we would call
hash_page to look up the Linux PTE for the address and create a HPTE.
However, hash_page is fairly complex and takes some locks, so to
avoid the possibility of deadlock, we check the preemption count
to see if we are in a (pseudo-)NMI handler, and if so, we don't call
hash_page but instead treat it like a bad access that will get
reported up through the exception table mechanism.  An interrupt
whose handler runs even though the interrupt occurred when
soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI
handler, which should use nmi_enter()/nmi_exit() rather than
irq_enter()/irq_exit().

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-18 14:48:43 +10:00
Linus Torvalds
d00aa6695b Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits)
  perf_counter: Zero dead bytes from ftrace raw samples size alignment
  perf_counter: Subtract the buffer size field from the event record size
  perf_counter: Require CAP_SYS_ADMIN for raw tracepoint data
  perf_counter: Correct PERF_SAMPLE_RAW output
  perf tools: callchain: Fix bad rounding of minimum rate
  perf_counter tools: Fix libbfd detection for systems with libz dependency
  perf: "Longum est iter per praecepta, breve et efficax per exempla"
  perf_counter: Fix a race on perf_counter_ctx
  perf_counter: Fix tracepoint sampling to be part of generic sampling
  perf_counter: Work around gcc warning by initializing tracepoint record unconditionally
  perf tools: callchain: Fix sum of percentages to be 100% by displaying amount of ignored chains in fractal mode
  perf tools: callchain: Fix 'perf report' display to be callchain by default
  perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains
  perf record: Fix the -A UI for empty or non-existent perf.data
  perf util: Fix do_read() to fail on EOF instead of busy-looping
  perf list: Fix the output to not include tracepoints without an id
  perf_counter/powerpc: Fix oops on cpus without perf_counter hardware support
  perf stat: Fix tool option consistency: rename -S/--scale to -c/--scale
  perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc)
  perf report: Fix per task mult-counter stat reporting
  ...
2009-08-10 11:48:51 -07:00
Benjamin Herrenschmidt
b2f2e8fee3 powerpc/dma: pci_set_dma_mask() shouldn't fail if mask fits in RAM
On an iMac G5, the b43 driver is failing to initialise because trying to
set the dma mask to 30-bit fails. Even though there's only 512MiB of RAM
in the machine anyway:
	https://bugzilla.redhat.com/show_bug.cgi?id=514787

We should probably let it succeed if the available RAM in the system
doesn't exceed the requested limit.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-10 16:36:38 +10:00
Paul Mackerras
f36a1a133a perf_counter/powerpc: Fix oops on cpus without perf_counter hardware support
If we have the powerpc perf_counter backend compiled in, but
the cpu we are running on is one where we don't support the
PMU, we currently oops in hw_perf_group_sched_in if we try to
use any counters, because ppmu is NULL in that case, and we
unconditionally dereference ppmu.

This fixes the problem by adding a check if ppmu is NULL at the
beginning of hw_perf_group_sched_in, and also at the beginning
of the other functions that get called from the perf_counter
core, i.e. hw_perf_disable, hw_perf_enable, and
hw_perf_counter_setup.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: benh@kernel.crashing.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:37 +02:00
Benjamin Herrenschmidt
e0d82a0a4e perf_counter/powerpc: Check oprofile_cpu_type for NULL before using it
If the current CPU doesn't support performance counters,
cur_cpu_spec->oprofile_cpu_type can be NULL. The current
perf_counter modules don't test for that case and would thus
crash at boot time.

Bug reported by David Woodhouse.

Reported-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul Mackerras <paulus@samba.org>
LKML-Reference: <19066.48028.446975.501454@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 13:55:09 +02:00
FUJITA Tomonori
8ab7ff42c9 powerpc: remove unused swiotlb_phys_to_bus() and swiotlb_bus_to_phys()
phys_to_dma() and dma_to_phys() are used instead of
swiotlb_phys_to_bus() and swiotlb_bus_to_phys().

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
2009-07-28 14:19:20 +09:00
FUJITA Tomonori
30945fdf6a powerpc: remove unncesary swiotlb_arch_address_needs_mapping
swiotlb doesn't use swiotlb_arch_address_needs_mapping(); it uses
dma_capalbe(). We can remove unnecessary
swiotlb_arch_address_needs_mapping().

We can remove swiotlb_addr_needs_map() and is_buffer_dma_capable() in
swiotlb_pci_addr_needs_map() too; dma_capable() handles the features
that both provide.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
2009-07-28 14:19:19 +09:00
FUJITA Tomonori
02ca646e73 swiotlb: remove unnecessary swiotlb_bus_to_virt
swiotlb_bus_to_virt is unncessary; we can use swiotlb_bus_to_phys and
phys_to_virt instead.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
2009-07-28 14:19:18 +09:00
Andreas Schwab
0115cb544b powerpc: Fix another bug in move of altivec code to vector.S
When moving load_up_altivec to vector.S a typo in a comment caused a
thinko setting the wrong variable.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-15 17:41:46 +10:00
Dave Kleikamp
28477fb1ed powerpc: Fix booke user_disable_single_step()
On booke processors, gdb is seeing spurious SIGTRAPs when setting a
watchpoint.

user_disable_single_step() simply quits when the DAC is non-zero.  It should
be clearing the DBCR0_IC and DBCR0_BT bits from the dbcr0 register and
TIF_SINGLESTEP from the thread flag.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-15 17:41:45 +10:00
Alexey Dobriyan
405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Linus Torvalds
85be928c41 Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
  perf report: Add "Fractal" mode output - support callchains with relative overhead rate
  perf_counter tools: callchains: Manage the cumul hits on the fly
  perf report: Change default callchain parameters
  perf report: Use a modifiable string for default callchain options
  perf report: Warn on callchain output request from non-callchain file
  x86: atomic64: Inline atomic64_read() again
  x86: atomic64: Clean up atomic64_sub_and_test() and atomic64_add_negative()
  x86: atomic64: Improve atomic64_xchg()
  x86: atomic64: Export APIs to modules
  x86: atomic64: Improve atomic64_read()
  x86: atomic64: Code atomic(64)_read and atomic(64)_set in C not CPP
  x86: atomic64: Fix unclean type use in atomic64_xchg()
  x86: atomic64: Make atomic_read() type-safe
  x86: atomic64: Reduce size of functions
  x86: atomic64: Improve atomic64_add_return()
  x86: atomic64: Improve cmpxchg8b()
  x86: atomic64: Improve atomic64_read()
  x86: atomic64: Move the 32-bit atomic64_t implementation to a .c file
  x86: atomic64: The atomic64_t data type should be 8 bytes aligned on 32-bit too
  perf report: Annotate variable initialization
  ...
2009-07-10 14:25:03 -07:00
Huang Weiyi
3665ee36fa powerpc/perf_counter: Remove duplicated #include
Remove duplicated #include('s) in
  arch/powerpc/kernel/mpc7450-pmu.c
  arch/powerpc/kernel/ppc970-pmu.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-08 13:50:22 +10:00