Commit Graph

126 Commits

Author SHA1 Message Date
Pavel Machek
db4315d6f5 timer_list: print relative expiry time signed
Relative expiry time can get negative, so it should be signed.

Signed-off-by: Pavel Machek <Pavel@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-17 17:29:38 +01:00
john stultz
e13a2e61dd ntp: correct inconsistent interval/tick_length usage
clocksource initialization and error accumulation.  This corrects a 280ppm
drift seen on some systems using acpi_pm, and affects other clocksources as
well (likely to a lesser degree).

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-10 10:48:03 +01:00
Li Zefan
3eb056764d time: fix typo in comments
Fix typo in comments.

BTW: I have to fix coding style in arch/ia64/kernel/time.c also, otherwise
checkpatch.pl will be complaining.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Li Zefan
cf4fc6cb76 timekeeping: rename timekeeping_is_continuous to timekeeping_valid_for_hres
Function timekeeping_is_continuous() no longer checks flag
CLOCK_IS_CONTINUOUS, and it checks CLOCK_SOURCE_VALID_FOR_HRES now.  So rename
the function accordingly.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Li Zefan
0b858e6ff9 clockevent: simplify list operations
list_for_each_safe() suffices here.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Li Zefan
818c357802 clocksource: remove redundant code
Flag CLOCK_SOURCE_WATCHDOG is cleared twice.  Note clocksource_change_rating()
won't do anyting with the cs flag.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Miao Xie
5e2cb1018a time: fix sysfs_show_{available,current}_clocksources() buffer overflow problem
I found that there is a buffer overflow problem in the following code.

Version:	2.6.24-rc2,
File:		kernel/time/clocksource.c:417-432
--------------------------------------------------------------------
static ssize_t
sysfs_show_available_clocksources(struct sys_device *dev, char *buf)
{
	struct clocksource *src;
	char *curr = buf;

	spin_lock_irq(&clocksource_lock);
	list_for_each_entry(src, &clocksource_list, list) {
		curr += sprintf(curr, "%s ", src->name);
	}
	spin_unlock_irq(&clocksource_lock);

	curr += sprintf(curr, "\n");

	return curr - buf;
}
-----------------------------------------------------------------------

sysfs_show_current_clocksources() also has the same problem though in practice
the size of current clocksource's name won't exceed PAGE_SIZE.

I fix the bug by using snprintf according to the specification of the kernel
(Version:2.6.24-rc2,File:Documentation/filesystems/sysfs.txt)

Fix sysfs_show_available_clocksources() and sysfs_show_current_clocksources()
buffer overflow problem with snprintf().

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:03 -08:00
Thomas Gleixner
5df7fa1c62 tick-sched: add more debug information
To allow better diagnosis of tick-sched related, especially NOHZ
related problems, we need to know when the last wakeup via an irq
happened and when the CPU left the idle state.

Add two fields (idle_waketime, idle_exittime) to the tick_sched
structure and add them to the timer_list output.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-01 17:45:14 +01:00
Thomas Gleixner
1001d0a9ee timekeeping: update xtime_cache when time(zone) changes
xtime_cache needs to be updated whenever xtime and or wall_to_monotic
are changed. Otherwise users of xtime_cache might see a stale (and in
the case of timezone changes utterly wrong) value until the next
update happens.

Fixup the obvious places, which miss this update.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <johnstul@us.ibm.com>
Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-01 17:45:13 +01:00
Venki Pallipadi
6378ddb592 time: track accurate idle time with tick_sched.idle_sleeptime
Current idle time in kstat is based on jiffies and is coarse grained.
tick_sched.idle_sleeptime is making some attempt to keep track of idle time
in a fine grained manner.  But, it is not handling the time spent in
interrupts fully.

Make tick_sched.idle_sleeptime accurate with respect to time spent on
handling interrupts and also add tick_sched.idle_lastupdate, which keeps
track of last time when idle_sleeptime was updated.

This statistics will be crucial for cpufreq-ondemand governor, which can
shed some conservative gaurd band that is uses today while setting the
frequency.  The ondemand changes that uses the exact idle time is coming
soon.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:04 +01:00
john stultz
bbe4d18ac2 NTP: correct inconsistent ntp interval/tick_length usage
I recently noticed on one of my boxes that when synched with an NTP
server, the drift value reported for the system was ~283ppm. While in
some cases, clock hardware can be that bad, it struck me as unusual as
the system was using the acpi_pm clocksource, which is one of the more
trustworthy and accurate clocksources on x86 hardware.

I brought up another system and let it sync to the same NTP server, and
I noticed a similar 280some ppm drift.

In looking at the code, I found that the acpi_pm's constant frequency
was being computed correctly at boot-up, however once the system was up,
even without the ntp daemon running, the clocksource's frequency was
being modified by the clocksource_adjust() function.

Digging deeper, I realized that in the code that keeps track of how much
the clocksource is skewing from the ntp desired time, we were using
different lengths to establish how long an time interval was.

The clocksource was being setup with the following interval:
	NTP_INTERVAL_LENGTH = NSEC_PER_SEC/NTP_INTERVAL_FREQ

While the ntp code was using the tick_length_base value:
	tick_length_base ~= (tick_usec * NSEC_PER_USEC * USER_HZ)
					/NTP_INTERVAL_FREQ

The subtle difference is:
	(tick_usec * NSEC_PER_USEC * USER_HZ) != NSEC_PER_SEC

This difference in calculation was causing the clocksource correction
code to apply a correction factor to the clocksource so the two
intervals were the same, however this results in the actual frequency of
the clocksource to be made incorrect. I believe this difference would
affect all clocksources, although to differing degrees depending on the
clocksource resolution.

The issue was introduced when my HZ free ntp patch landed in 2.6.21-rc1,
so my apologies for the mistake, and for not noticing it until now.

The following patch, corrects the clocksource's initialization code so
it uses the same interval length as the code in ntp.c. After applying
this patch, the drift value for the same system went from ~283ppm to
only 2.635ppm.

I believe this patch to be good, however it does affect all arches and
I've only tested on x86, so some caution is advised. I do think it would
be a likely candidate for a stable 2.6.24.x release.

Any thoughts or feedback would be appreciated.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:03 +01:00
Ingo Molnar
45fe4fe191 x86: make clockevents more robust
detect zero event-device multiplicators - they then cause
division-by-zero crashes if a clockevent has been initialized
incorrectly.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:03 +01:00
Thomas Gleixner
4713e22ce8 clocksource: add unregister function to disable unusable clocksources
On x86 the PIT might become an unusable clocksource. Add an unregister
function to provide a possibilty to remove the PIT from the list of
available clock sources.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30 13:30:02 +01:00
Andi Kleen
1ada5cba6a clocksource: make clocksource watchdog cycle through online CPUs
This way it checks if the clocks are synchronized between CPUs too.
This might be able to detect slowly drifting TSCs which only
go wrong over longer time.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:02 +01:00
Parag Warudkar
1077f5a917 clocksource.c: use init_timer_deferrable for clocksource_watchdog
clocksource_watchdog can use a deferrable timer - reduces wakeups from
idle per second.

Signed-off-by: Parag Warudkar <parag.warudkar@gmail.com>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:01 +01:00
Geert Uytterhoeven
efd9ac8630 time: fold __get_realtime_clock_ts() into getnstimeofday()
- getnstimeofday() was just a wrapper around __get_realtime_clock_ts()
  - Replace calls to __get_realtime_clock_ts() by calls to getnstimeofday()
  - Fix bogus reference to get_realtime_clock_ts(), which never existed

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:01 +01:00
Thomas Gleixner
186e3cb8a4 timer: clean up tick-broadcast.c
clean up tick-broadcast.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30 13:30:01 +01:00
Pavel Machek
b10db7f0d2 time: more timer related cleanups
I was confused by FSEC = 10^15 NSEC statement, plus small whitespace
fixes. When there's copyright, there should be GPL.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:00 +01:00
Pavel Machek
4c9dc64122 time: timer cleanups
Small cleanups to tick-related code. Wrong preempt count is followed
by BUG(), so it is hardly KERN_WARNING.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:00 +01:00
Peter Zijlstra
2d44ae4d71 hrtimer: clean up cpu->base locking tricks
In order to more easily allow for the scheduler to use timers, clean up
the locking a bit.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-25 21:08:31 +01:00
Peter Zijlstra
48d5e25821 sched: rt throttling vs no_hz
We need to teach no_hz about the rt throttling because its tick driven.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-25 21:08:31 +01:00
Kay Sievers
af5ca3f4ec Driver core: change sysdev classes to use dynamic kobject names
All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:40 -08:00
Thomas Gleixner
cdc6f27d9e clockevents: fix reprogramming decision in oneshot broadcast
Resolve the following regression of a choppy, almost unusable laptop:

 http://lkml.org/lkml/2007/12/7/299
 http://bugzilla.kernel.org/show_bug.cgi?id=9525

A previous version of the code did the reprogramming of the broadcast
device in the return from idle code. This was removed, but the logic in
tick_handle_oneshot_broadcast() was kept the same.

When a broadcast interrupt happens we signal the expiry to all CPUs
which have an expired event. If none of the CPUs has an expired event,
which can happen in dyntick mode, then we reprogram the broadcast
device. We do not reprogram otherwise, but this is only correct if all
CPUs, which are in the idle broadcast state have been woken up.

The code ignores, that there might be pending not yet expired events on
other CPUs, which are in the idle broadcast state. So the delivery of
those events can be delayed for quite a time.

Change the tick_handle_oneshot_broadcast() function to check for CPUs,
which are in broadcast state and are not woken up by the current event,
and enforce the rearming of the broadcast device for those CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-18 18:05:58 +01:00
Thomas Gleixner
167b1de3ee clockevents: warn once when program_event() is called with negative expiry
The hrtimer problem with large relative timeouts resulting in a
negative expiry time went unnoticed as there is no check in the
clockevents_program_event() code. Put a check there with a WARN_ONCE
to avoid such problems in the future.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-07 19:16:17 +01:00
Thomas Gleixner
d393820446 softlockup: fix false positives on CONFIG_NOHZ
David Miller reported soft lockup false-positives that trigger
on NOHZ due to CPUs idling for more than 10 seconds.

The solution is touch the softlockup watchdog when we return from
idle. (by definition we are not 'locked up' when we were idle)

 http://bugzilla.kernel.org/show_bug.cgi?id=9409

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-28 15:52:56 +01:00
John Stultz
52bfb36050 time: add ADJ_OFFSET_SS_READ
Michael Kerrisk reported that a long standing bug in the adjtimex()
system call causes glibc's adjtime(3) function to deliver the wrong
results if 'delta' is NULL.

add the ADJ_OFFSET_SS_READ API detail, which will be used by glibc
to fix this API compatibility bug.

Also see: http://bugzilla.kernel.org/show_bug.cgi?id=6761

[ mingo@elte.hu: added patch description and made it backwards compatible ]

NOTE: the new flag is defined 0xa001 so that it returns -EINVAL on
older kernels - this way glibc can use it safely. Suggested by Ulrich
Drepper.

Acked-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-26 20:42:19 +01:00
David P. Reed
fa6a1a554b ntp: fix typo that makes sync_cmos_clock erratic
Fix a typo in ntp.c that has caused updating of the persistent (RTC)
clock when synced to NTP to behave erratically.

When debugging a freeze that arises on my AMD64 machines when I
run the ntpd service, I added a number of printk's to monitor the
sync_cmos_clock procedure.  I discovered that it was not syncing to
cmos RTC every 11 minutes as documented, but instead would keep trying
every second for hours at a time.  The reason turned out to be a typo
in sync_cmos_clock, where it attempts to ensure that
update_persistent_clock is called very close to 500 msec. after a 1
second boundary (required by the PC RTC's spec). That typo referred to
"xtime" in one spot, rather than "now", which is derived from "xtime"
but not equal to it.  This makes the test erratic, creating a
"coin-flip" that decides when update_persistent_clock is called - when
it is called, which is rarely, it may be at any time during the one
second period, rather than close to 500 msec, so the value written is
needlessly incorrect, too.

Signed-off-by: David P. Reed
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
Li Zefan
8dce39c231 time: fix inconsistent function names in comments
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-05 15:12:33 -08:00
Vegard Nossum
129f1d2c53 timer_list: Fix printk format strings
This makes sure printk format strings contain no more than a single
line.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-29 09:39:38 +01:00
Adrian Bunk
64e38eb082 clockevents: unexport tick_nohz_get_sleep_length
This patch removes the unused 
EXPORT_SYMBOL_GPL(tick_nohz_get_sleep_length).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-29 09:39:38 +01:00
Linus Torvalds
c4ec207173 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (41 commits)
  ACPICA: hw: Don't carry spinlock over suspend
  ACPICA: hw: remove use_lock flag from acpi_hw_register_{read, write}
  ACPI: cpuidle: port idle timer suspend/resume workaround to cpuidle
  ACPI: clean up acpi_enter_sleep_state_prep
  Hibernation: Make sure that ACPI is enabled in acpi_hibernation_finish
  ACPI: suppress uninitialized var warning
  cpuidle: consolidate 2.6.22 cpuidle branch into one patch
  ACPI: thinkpad-acpi: skip blanks before the data when parsing sysfs
  ACPI: AC: Add sysfs interface
  ACPI: SBS: Add sysfs alarm
  ACPI: SBS: Add ACPI_PROCFS around procfs handling code.
  ACPI: SBS: Add support for power_supply class (and sysfs)
  ACPI: SBS: Make SBS reads table-driven.
  ACPI: SBS: Simplify data structures in SBS
  ACPI: SBS: Split host controller (ACPI0001) from SBS driver (ACPI0002)
  ACPI: EC: Add new query handler to list head.
  ACPI: Add acpi_bus_generate_event4() function
  ACPI: Battery: add sysfs alarm
  ACPI: Battery: Add sysfs support
  ACPI: Battery: Misc clean-ups, no functional changes
  ...

Fix up conflicts in drivers/misc/thinkpad_acpi.[ch] manually
2007-10-19 13:12:46 -07:00
Matthias Kaehlcke
2e1975868a kernel/time/clocksource.c: Use list_for_each_entry instead of list_for_each
kernel/time/clocksource.c: Convert list_for_each to
list_for_each_entry in clocksource_resume(),
sysfs_override_clocksource() and show_available_clocksources()

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:38 -07:00
Thomas Gleixner
3dfbc88464 x86: C1E late detection fix. Really switch off lapic timer
Doh, I completely missed that devices marked DUMMY are not running
the set_mode function. So we force broadcasting, but we keep the
local APIC timer running.

Let the clock event layer mark the device _after_ switching it off.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-17 20:15:13 +02:00
john stultz
b2d9323d13 Use num_possible_cpus() instead of NR_CPUS for timer distribution
To avoid lock contention, we distribute the sched_timer calls across the
cpus so they do not trigger at the same instant.  However, I used NR_CPUS,
which can cause needless grouping on small smp systems depending on your
kernel config.  This patch converts to using num_possible_cpus() so we
spread it as evenly as possible on every machine.

Briefly tested w/ NR_CPUS=255 and verified reduced contention.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:53 -07:00
Adrian Bunk
ba2a631b14 kernel/time/timekeeping.c: cleanups
- remove the no longer required __attribute__((weak)) of xtime_lock
- remove the following no longer used EXPORT_SYMBOL's:
  - xtime
  - xtime_lock

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:53 -07:00
Avi Kivity
bf020cb7b3 time: simplify smp_call_function_single() call sequence
smp_call_function_single() now knows how to call the function on the
current cpu.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:48 -07:00
Ingo Molnar
f20bf61256 time: introduce xtime_seconds
improve performance of sys_time(). sys_time() returns time in seconds,
but it does so by calling do_gettimeofday() and then returning the
tv_sec portion of the GTOD time. But the data structure "xtime", which
is updated by every timer/scheduler tick, already offers HZ granularity
time.

the patch improves the sysbench oltp macrobenchmark by 4-5% on an AMD
dual-core system:

v2.6.23:

#threads

   1:     transactions:                        4073   (407.23 per sec.)
   2:     transactions:                        8530   (852.81 per sec.)
   3:     transactions:                        8321   (831.88 per sec.)
   4:     transactions:                        8407   (840.58 per sec.)
   5:     transactions:                        8070   (806.74 per sec.)

v2.6.23 + sys_time-speedup.patch:

   1:     transactions:                        4281   (428.09 per sec.)
   2:     transactions:                        8910   (890.85 per sec.)
   3:     transactions:                        8659   (865.79 per sec.)
   4:     transactions:                        8676   (867.34 per sec.)
   5:     transactions:                        8532   (852.91 per sec.)

and by 4-5% on an Intel dual-core system too:

2.6.23:

  1:     transactions:                        4560   (455.94 per sec.)
  2:     transactions:                        10094  (1009.30 per sec.)
  3:     transactions:                        9755   (975.36 per sec.)
  4:     transactions:                        9859   (985.78 per sec.)
  5:     transactions:                        9701   (969.72 per sec.)

2.6.23 + sys_time-speedup.patch:

  1:     transactions:                        4779   (477.84 per sec.)
  2:     transactions:                        10103  (1010.14 per sec.)
  3:     transactions:                        10141  (1013.93 per sec.)
  4:     transactions:                        10371  (1036.89 per sec.)
  5:     transactions:                        10178  (1017.50 per sec.)

(the more CPUs the system has, the more speedup this patch gives for
this particular workload.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 10:01:50 -07:00
Thomas Gleixner
1595f452f3 clockevents: introduce force broadcast notifier
The 64bit SMP bootup is slightly different to the 32bit one. It enables
the boot CPU local APIC timer before all CPUs are brought up. Some AMD C1E
systems have the C1E feature flag only set in the secondary CPU. Due to
the early enable of the boot CPU local APIC timer the APIC timer is
registered as a fully functional device. When we detect the wreckage during
the bringup of the secondary CPU, we need to force the boot CPU into
broadcast mode. 

Add a new notifier reason and implement the force broadcast in the clock
events layer.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-14 22:57:45 +02:00
Venki Pallipadi
4a93232dab clock events: allow replacement of broadcast timer
Change the broadcast timer, if a timer with higher rating becomes available.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-12 23:04:23 +02:00
Thomas Gleixner
c8a1d398de clockevents: fix periodic broadcast for oneshot devices
The next_event member of the clock event device is used to keep track
of the next periodic event. For one shot only devices it is wrong to
clear the variable, as the next event will be based on it.

Pointed out by Ralf Baechle

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2007-10-12 23:04:06 +02:00
Thomas Gleixner
de68d9b173 clockevents: Allow build w/o run-tine usage for migration purposes
Migration aid to allow preparatory patches which introduce not yet
used parts of clock events code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2007-10-12 23:04:05 +02:00
Len Brown
4f86d3a8e2 cpuidle: consolidate 2.6.22 cpuidle branch into one patch
commit e5a16b1f9eec0af7cfa0830304b41c1c0833cf9f
Author: Len Brown <len.brown@intel.com>
Date:   Tue Oct 2 23:44:44 2007 -0400

    cpuidle: shrink diff

    processor_idle.c |  440 +++++++++++++++++++++++++++++++++++++++++--
    1 file changed, 429 insertions(+), 11 deletions(-)

    Signed-off-by: Len Brown <len.brown@intel.com>

commit dfbb9d5aedfb18848a3e0d6f6e3e4969febb209c
Author: Len Brown <len.brown@intel.com>
Date:   Wed Sep 26 02:17:55 2007 -0400

    cpuidle: reduce diff size

    Reduces the cpuidle processor_idle.c diff vs 2.6.22 from this
     processor_idle.c | 2006 ++++++++++++++++++++++++++-----------------
     1 file changed, 1219 insertions(+), 787 deletions(-)

    to this:
     processor_idle.c |  502 +++++++++++++++++++++++++++++++++++++++----
     1 file changed, 458 insertions(+), 44 deletions(-)

    ...for the purpose of making the cpuilde patch less invasive
    and easier to review.

    no functional changes.  build tested only.

    Signed-off-by: Len Brown <len.brown@intel.com>

commit 889172fc915f5a7fe20f35b133cbd205ce69bf6c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:40:05 2007 -0700

    cpuidle: Retain old ACPI policy for !CONFIG_CPU_IDLE

    Retain the old policy in processor_idle, so that when CPU_IDLE is not
    configured, old C-state policy will still be used. This provides a
    clean gradual migration path from old ACPI policy to new cpuidle
    based policy.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 9544a8181edc7ecc33b3bfd69271571f98ed08bc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:39:17 2007 -0700

    cpuidle: Configure governors by default

    Quoting Len "Do not give an option to users to shoot themselves in the foot".

    Remove the configurability of ladder and menu governors as they are
    needed for default policy of cpuidle. That way users will not be able to
    have cpuidle without any policy loosing all C-state power savings.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8975059a2c1e56cfe83d1bcf031bcf4cb39be743
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:27:07 2007 -0400

    CPUIDLE: load ACPI properly when CPUIDLE is disabled

    Change the registration return codes for when CPUIDLE
    support is not compiled into the kernel.  As a result, the ACPI
    processor driver will load properly even if CPUIDLE is unavailable.
    However, it may be possible to cleanup the ACPI processor driver further
    and eliminate some dead code paths.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit e0322e2b58dd1b12ec669bf84693efe0dc2414a8
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:26:06 2007 -0400

    CPUIDLE: remove cpuidle_get_bm_activity()

    Remove cpuidle_get_bm_activity() and updates governors
    accordingly.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 18a6e770d5c82ba26653e53d240caa617e09e9ab
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:58 2007 -0400

    CPUIDLE: max_cstate fix

    Currently max_cstate is limited to 0, resulting in no idle processor
    power management on ACPI platforms.  This patch restores the value to
    the array size.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1fdc0887286179b40ce24bcdbde663172e205ef0
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:40 2007 -0400

    CPUIDLE: handle BM detection inside the ACPI Processor driver

    Update the ACPI processor driver to detect BM activity and
    limit state entry depth internally, rather than exposing such
    requirements to CPUIDLE.  As a result, CPUIDLE can drop this
    ACPI-specific interface and become more platform independent.  BM
    activity is now handled much more aggressively than it was in the
    original implementation, so some testing coverage may be needed to
    verify that this doesn't introduce any DMA buffer under-run issues.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0ef38840db666f48e3cdd2b769da676c57228dd9
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:14 2007 -0400

    CPUIDLE: menu governor updates

    Tweak the menu governor to more effectively handle non-timer
    break events.  Non-timer break events are detected by comparing the
    actual sleep time to the expected sleep time.  In future revisions, it
    may be more reliable to use the timer data structures directly.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit bb4d74fca63fa96cf3ace644b15ae0f12b7df5a1
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:24:40 2007 -0400

    CPUIDLE: fix 'current_governor' sysfs entry

    Allow the "current_governor" sysfs entry to properly handle
    input terminated with '\n'.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit df3c71559bb69b125f1a48971bf0d17f78bbdf47
Author: Len Brown <len.brown@intel.com>
Date:   Sun Aug 12 02:00:45 2007 -0400

    cpuidle: fix IA64 build (again)

    Signed-off-by: Len Brown <len.brown@intel.com>

commit a02064579e3f9530fd31baae16b1fc46b5a7bca8
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:27 2007 -0400

    cpuidle: Remove support for runtime changing of max_cstate

    Remove support for runtime changeability of max_cstate. Drivers can use
    use latency APIs.

    max_cstate can still be used as a boot time option and dmi override.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0912a44b13adf22f5e3f607d263aed23b4910d7e
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:16 2007 -0400

    cpuidle: Remove ACPI cstate_limit calls from ipw2100

    ipw2100 already has code to use accetable_latency interfaces to limit the
    C-state. Remove the calls to acpi_set_cstate_limit and acpi_get_cstate_limit
    as they are redundant.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c649a76e76be6bff1fd770d0a775798813a3f6e0
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:35:39 2007 -0400

    cpuidle: compile fix for pause and resume functions

    Fix the compilation failure when cpuidle is not compiled in.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Acked-by: Adam Belay <adam.belay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 2305a5920fb8ee6ccec1c62ade05aa8351091d71
Author: Adam Belay <abelay@novell.com>
Date:   Thu Jul 19 00:49:00 2007 -0400

    cpuidle: re-write

    Some portions have been rewritten to make the code cleaner and lighter
    weight.  The following is a list of changes:

    1.) the state name is now included in the sysfs interface
    2.) detection, hotplug, and available state modifications are handled by
    CPUIDLE drivers directly
    3.) the CPUIDLE idle handler is only ever installed when at least one
    cpuidle_device is enabled and ready
    4.) the menu governor BM code no longer overflows
    5.) the sysfs attributes are now printed as unsigned integers, avoiding
    negative values
    6.) a variety of other small cleanups

    Also, Idle drivers are no longer swappable during runtime through the
    CPUIDLE sysfs inteface.  On i386 and x86_64 most idle handlers (e.g.
    poll, mwait, halt, etc.) don't benefit from an infrastructure that
    supports multiple states, so I think using a more general case idle
    handler selection mechanism would be cleaner.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Acked-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit df25b6b56955714e6e24b574d88d1fd11f0c3ee5
Author: Len Brown <len.brown@intel.com>
Date:   Tue Jul 24 17:08:21 2007 -0400

    cpuidle: fix IA64 buid

    Signed-off-by: Len Brown <len.brown@intel.com>

commit fd6ada4c14488755ff7068860078c437431fbccd
Author: Adrian Bunk <bunk@stusta.de>
Date:   Mon Jul 9 11:33:13 2007 -0700

    cpuidle: static

    make cpuidle_replace_governor() static

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c1d4a2cebcadf2429c0c72e1d29aa2a9684c32e0
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Jul 3 00:54:40 2007 -0400

    cpuidle: static

    This patch makes the needlessly global struct menu_governor static.

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit dbf8780c6e8d572c2c273da97ed1cca7608fd999
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:49:14 2007 -0400

    export symbol tick_nohz_get_sleep_length

    ERROR: "tick_nohz_get_sleep_length" [drivers/cpuidle/governors/menu.ko] undefined!
    ERROR: "tick_nohz_get_idle_jiffies" [drivers/cpuidle/governors/menu.ko] undefined!

    And please be sure to get your changes to core kernel suitably reviewed.

    Cc: Adam Belay <abelay@novell.com>
    Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: john stultz <johnstul@us.ibm.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 29f0e248e7017be15f99febf9143a2cef00b2961
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:43:04 2007 -0400

    tick.h needs hrtimer.h

    It uses hrtimers.

    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit e40cede7d63a029e92712a3fe02faee60cc38fb4
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:40:34 2007 -0400

    cpuidle: first round of documentation updates

    Documentation changes based on Pavel's feedback.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 83b42be2efece386976507555c29e7773a0dfcd1
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:39:25 2007 -0400

    cpuidle: add rating to the governors and pick the one with highest rating by default

    Introduce a governor rating scheme to pick the right governor by default.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit d2a74b8c5e8f22def4709330d4bfc4a29209b71c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:38:08 2007 -0400

    cpuidle: make cpuidle sysfs driver governor switch off by default

    Make default cpuidle sysfs to show current_governor and current_driver in
    read-only mode.  More elaborate available_governors and available_drivers with
    writeable current_governor and current_driver interface only appear with
    "cpuidle_sysfs_switch" boot parameter.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1f60a0e80bf83cf6b55c8845bbe5596ed8f6307b
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:37:00 2007 -0400

    cpuidle: menu governor: change the early break condition

    Change the C-state early break out algorithm in menu governor.

    We only look at early breakouts that result in wakeups shorter than idle
    state's target_residency.  If such a breakout is frequent enough, eliminate
    the particular idle state upto a timeout period.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 45a42095cf64b003b4a69be3ce7f434f97d7af51
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:35:38 2007 -0400

    cpuidle: fix uninitialized variable in sysfs routine

    Fix the uninitialized usage of ret.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 80dca7cdba3e6ee13eae277660873ab9584eb3be
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:34:16 2007 -0400

    cpuidle: reenable /proc/acpi//power interface for the time being

    Keep /proc/acpi/processor/CPU*/power around for a while as powertop depends
    on it. It will be marked deprecated and removed in future. powertop can use
    cpuidle interfaces instead.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 589c37c2646c5e3813a51255a5ee1159cb4c33fc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:32:37 2007 -0400

    cpuidle: menu governor and hrtimer compile fix

    Compile fix for menu governor.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0ba80bd9ab3ed304cb4f19b722e4cc6740588b5e
Author: Len Brown <len.brown@intel.com>
Date:   Thu May 31 22:51:43 2007 -0400

    cpuidle: build fix - cpuidle vs ipw2100 module

    ERROR: "acpi_set_cstate_limit" [drivers/net/wireless/ipw2100.ko] undefined!

    Signed-off-by: Len Brown <len.brown@intel.com>

commit d7d8fa7f96a7f7682be7c6cc0cc53fa7a18c3b58
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:07 2007 -0400

    cpuidle: add the 'menu' governor

    Here is my first take at implementing an idle PM governor that takes
    full advantage of NO_HZ.  I call it the 'menu' governor because it
    considers the full list of idle states before each entry.

    I've kept the implementation fairly simple.  It attempts to guess the
    next residency time and then chooses a state that would meet at least
    the break-even point between power savings and entry cost.  To this end,
    it selects the deepest idle state that satisfies the following
    constraints:
         1. If the idle time elapsed since bus master activity was detected
            is below a threshold (currently 20 ms), then limit the selection
            to C2-type or above.
         2. Do not choose a state with a break-even residency that exceeds
            the expected time remaining until the next timer interrupt.
         3. Do not choose a state with a break-even residency that exceeds
            the elapsed time between the last pair of break events,
            excluding timer interrupts.

    This governor has an advantage over "ladder" governor because it
    proactively checks how much time remains until the next timer interrupt
    using the tick infrastructure.  Also, it handles device interrupt
    activity more intelligently by not including timer interrupts in break
    event calculations.  Finally, it doesn't make policy decisions using the
    number of state entries, which can have variable residency times (NO_HZ
    makes these potentially very large), and instead only considers sleep
    time deltas.

    The menu governor can be selected during runtime using the cpuidle sysfs
    interface like so:
    "echo "menu" > /sys/devices/system/cpu/cpuidle/current_governor"

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit a4bec7e65aa3b7488b879d971651cc99a6c410fe
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:03 2007 -0400

    cpuidle: export time until next timer interrupt using NO_HZ

    Expose information about the time remaining until the next
    timer interrupt expires by utilizing the dynticks infrastructure.
    Also modify the main idle loop to allow dynticks to handle
    non-interrupt break events (e.g. DMA).  Finally, expose sleep ticks
    information to external code.  Thomas Gleixner is responsible for much
    of the code in this patch.  However, I've made some additional changes,
    so I'm probably responsible if there are any bugs or oversights :)

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 2929d8996fbc77f41a5ff86bb67cdde3ca7d2d72
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:46:58 2007 -0400

    cpuidle: governor API changes

    This patch prepares cpuidle for the menu governor.  It adds an optional
    stage after idle state entry to give the governor an opportunity to
    check why the state was exited.  Also it makes sure the idle loop
    returns after each state entry, allowing the appropriate dynticks code
    to run.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 3a7fd42f9825c3b03e364ca59baa751bb350775f
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Apr 26 00:03:59 2007 -0700

    cpuidle: hang fix

    Prevent hang on x86-64, when ACPI processor driver is added as a module on
    a system that does not support C-states.

    x86-64 expects all idle handlers to enable interrupts before returning from
    idle handler.  This is due to enter_idle(), exit_idle() races.  Make
    cpuidle_idle_call() confirm to this when there is no pm_idle_old.

    Also, cpuidle look at the return values of attch_driver() and set
    current_driver to NULL if attach fails on all CPUs.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 4893339a142afbd5b7c01ffadfd53d14746e858e
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:09 2007 +0800

    cpuidle: add support for max_cstate limit

    With CPUIDLE framework, the max_cstate (to limit max cpu c-state)
    parameter is ingored. Some systems require it to ignore C2/C3
    and some drivers like ipw require it too.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 43bbbbe1cb998cbd2df656f55bb3bfe30f30e7d1
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:13 2007 +0800

    cpuidle: add cpuidle_fore_redetect_devices API

    add cpuidle_force_redetect_devices API,
    which forces all CPU redetect idle states.
    Next patch will use it.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit d1edadd608f24836def5ec483d2edccfb37b1d19
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:01 2007 +0800

    cpuidle: fix sysfs related issue

    Fix the cpuidle sysfs issue.
    a. make kobject dynamicaly allocated
    b. fixed sysfs init issue to avoid suspend/resume issue

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 7169a5cc0d67b263978859672e86c13c23a5570d
Author: Randy Dunlap <randy.dunlap@oracle.com>
Date:   Wed Mar 28 22:52:53 2007 -0400

    cpuidle: 1-bit field must be unsigned

    A 1-bit bitfield has no room for a sign bit.
    drivers/cpuidle/governors/ladder.c:54:16: error: dubious bitfield without explicit `signed' or `unsigned'

    Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 4658620158dc2fbd9e4bcb213c5b6fb5d05ba7d4
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 28 22:52:41 2007 -0400

    cpuidle: fix boot hang

    Patch for cpuidle boot hang reported by Larry Finger here.
    http://www.ussg.iu.edu/hypermail/linux/kernel/0703.2/2025.html

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Larry Finger <larry.finger@lwfinger.net>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c17e168aa6e5fe3851baaae8df2fbc1cf11443a9
Author: Len Brown <len.brown@intel.com>
Date:   Wed Mar 7 04:37:53 2007 -0500

    cpuidle: ladder does not depend on ACPI

    build fix for CONFIG_ACPI=n

    In file included from drivers/cpuidle/governors/ladder.c:21:
    include/acpi/processor.h:88: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:106: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:168: error: expected specifier-qualifier-list before ‘acpi_handle’

    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8c91d958246bde68db0c3f0c57b535962ce861cb
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Mar 6 02:29:40 2007 -0800

    cpuidle: make code static

    This patch makes the following needlessly global code static:
    - driver.c: __cpuidle_find_driver()
    - governor.c: __cpuidle_find_governor()
    - ladder.c: struct ladder_governor

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0c39dc3187094c72c33ab65a64d2017b21f372d2
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 7 02:38:22 2007 -0500

    cpu_idle: fix build break

    This patch fixes a build breakage with !CONFIG_HOTPLUG_CPU and
    CONFIG_CPU_IDLE.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8112e3b115659b07df340ef170515799c0105f82
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Mar 6 02:29:39 2007 -0800

    cpuidle: build fix for !CPU_IDLE

    Fix the compile issues when CPU_IDLE is not configured.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1eb4431e9599cd25e0d9872f3c2c8986821839dd
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:57 2007 -0800

    cpuidle take2: Basic documentation for cpuidle

    Documentation for cpuidle infrastructure

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit ef5f15a8b79123a047285ec2e3899108661df779
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:03 2007 -0800

    cpuidle take2: Hookup ACPI C-states driver with cpuidle

    Hookup ACPI C-states onto generic cpuidle infrastructure.

    drivers/acpi/procesor_idle.c is now a ACPI C-states driver that registers as
    a driver in cpuidle infrastructure and the policy part is removed from
    drivers/acpi/processor_idle.c. We use governor in cpuidle instead.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 987196fa82d4db52c407e8c9d5dec884ba602183
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:52:57 2007 -0800

    cpuidle take2: Core cpuidle infrastructure

    Announcing 'cpuidle', a new CPU power management infrastructure to manage
    idle CPUs in a clean and efficient manner.
    cpuidle separates out the drivers that can provide support for multiple types
    of idle states and policy governors that decide on what idle state to use
    at run time.
    A cpuidle driver can support multiple idle states based on parameters like
    varying power consumption, wakeup latency, etc (ACPI C-states for example).
    A cpuidle governor can be usage model specific (laptop, server,
    laptop on battery etc).
    Main advantage of the infrastructure being, it allows independent development
    of drivers and governors and allows for better CPU power management.

    A huge thanks to Adam Belay and Shaohua Li who were part of this mini-project
    since its beginning and are greatly responsible for this patchset.

    This patch:

    Core cpuidle infrastructure.
    Introduces a new abstraction layer for cpuidle:
    * which manages drivers that can support multiple idles states. Drivers
      can be generic or particular to specific hardware/platform
    * allows pluging in multiple policy governors that can take idle state policy
      decision
    * The core also has a set of sysfs interfaces with which administrato can know
      about supported drivers and governors and switch them at run time.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>
2007-10-10 00:12:41 -04:00
Anton Blanchard
74922be148 Fix timer_stats printout of events/sec
When using /proc/timer_stats on ppc64 I noticed the events/sec field wasnt
accurate.  Sometimes the integer part was incorrect due to rounding (we
werent taking the fractional seconds into consideration).

The fraction part is also wrong, we need to pad the printf statement and
take the bottom three digits of 1000 times the value.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-07 16:28:43 -07:00
Thomas Gleixner
b7e113dc9d clockevents: remove the suspend/resume workaround^Wthinko
In a desparate attempt to fix the suspend/resume problem on Andrews
VAIO I added a workaround which enforced the broadcast of the oneshot
timer on resume. This was actually resolving the problem on the VAIO
but was just a stupid workaround, which was not tackling the root
cause: the assignement of lower idle C-States in the ACPI processor_idle
code. The cpuidle patches, which utilize the dynamic tick feature and
go faster into deeper C-states exposed the problem again. The correct
solution is the previous patch, which prevents lower C-states across
the suspend/resume.

Remove the enforcement code, including the conditional broadcast timer
arming, which helped to pamper over the real problem for quite a time.
The oneshot broadcast flag for the cpu, which runs the resume code can
never be set at the time when this code is executed. It only gets set,
when the CPU is entering a lower idle C-State.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-22 17:15:34 -07:00
Thomas Gleixner
5e41d0d60a clockevents: prevent stale tick update on offline cpu
Taking a cpu offline removes the cpu from the online mask before the
CPU_DEAD notification is done. The clock events layer does the cleanup
of the dead CPU from the CPU_DEAD notifier chain. tick_do_timer_cpu is
used to avoid xtime lock contention by assigning the task of jiffies
xtime updates to one CPU. If a CPU is taken offline, then this
assignment becomes stale. This went unnoticed because most of the time
the offline CPU went dead before the online CPU reached __cpu_die(),
where the CPU_DEAD state is checked. In the case that the offline CPU did
not reach the DEAD state before we reach __cpu_die(), the code in there
goes to sleep for 100ms. Due to the stale time update assignment, the
system is stuck forever.

Take the assignment away when a cpu is not longer in the cpu_online_mask.
We do this in the last call to tick_nohz_stop_sched_tick() when the offline
CPU is on the way to the final play_dead() idle entry.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-09-16 15:36:43 +02:00
Thomas Gleixner
31d9b3938c clockevents: do not shutdown the oneshot broadcast device
When a cpu goes offline it is removed from the broadcast masks. If the
mask becomes empty the code shuts down the broadcast device. This is
wrong, because the broadcast device needs to be ready for the online
cpu going idle (into a c-state, which stops the local apic timer).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-09-16 15:36:43 +02:00
Thomas Gleixner
07eec6af44 clockevents: Enforce oneshot broadcast when broadcast mask is set on resume
The jinxed VAIO refuses to resume without hitting keys on the keyboard
when this is not enforced. It is unclear why the cpu ends up in a lower
C State without notifying the clock events layer, but enforcing the
oneshot broadcast here is safe.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-09-16 15:36:43 +02:00
Thomas Gleixner
6a669ee8a7 timekeeping: Prevent time going backwards on resume
Timekeeping resume adjusts xtime by adding the slept time in seconds and
resets the reference value of the clock source (clock->cycle_last).
clock->cycle last is used to calculate the delta between the last xtime
update and the readout of the clock source in __get_nsec_offset(). xtime
plus the offset is the current time. The resume code ignores the delta
which had already elapsed between the last xtime update and the actual
time of suspend. If the suspend time is short, then we can see time
going backwards on resume.

Suspend:
offs_s = clock->read() - clock->cycle_last;
now = xtime + offs_s;
timekeeping_suspend_time = read_rtc();

Resume:
sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;

if sleep_time_seconds == 0 and offs_r < offs_s, then time goes
backwards.

Fix this by storing the offset from the last xtime update and add it to
xtime during resume, when we reset clock->cycle_last:

sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
xtime += offs_s;	/* Fixup xtime offset at suspend time */
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;

Thanks to Marcelo for tracking this down on the OLPC and providing the
necessary details to analyze the root cause.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Tosatti <marcelo@kvack.org>
2007-09-16 15:36:43 +02:00
Thomas Gleixner
3be9095063 timekeeping: access rtc outside of xtime lock
Lockdep complains about the access of rtc in timekeeping_suspend
inside the interrupt disabled region of the write locked xtime lock.
Move the access outside.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
2007-09-16 15:36:43 +02:00
Tony Breeds
298a5df45d Fix "no_sync_cmos_clock" logic inversion in kernel/time/ntp.c
Seems to me that this timer will only get started on platforms that say
they don't want it?

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Gabriel Paubert <paubert@iram.es>
Cc: Zachary Amsden <zach@vmware.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-11 17:21:27 -07:00