linux.git/drivers/acpi/processor_idle.c, branch v2.6.23

ACPI: disable lower idle C-states across suspend/resume

2007-09-23T00:15:34+00:00

device_suspend() calls ACPI suspend functions, which seems to have undesired
side effects on lower idle C-states. It took me some time to realize that
especially the VAIO BIOSes (both Andrews jinxed UP and my elfstruck SMP one)
show this effect. I'm quite sure that other bug reports against suspend/resume
about turning the system into a brick have the same root cause.

After fishing in the dark for quite some time, I realized that removing the ACPI
processor module before suspend (this removes the lower C-state functionality)
made the problem disappear. Interestingly enough the propability of having a
bricked box is influenced by various factors (interrupts, size of the ram image,
...). Even adding a bunch of printks in the wrong places made the problem go
away. The previous periodic tick implementation simply pampered over the
problem, which explains why the dyntick / clockevents changes made this more
prominent.

We avoid complex functionality during the boot process and we have to do the
same during suspend/resume. It is a similar scenario and equaly fragile.

Add suspend / resume functions to the ACPI processor code and disable the lower
idle C-states across suspend/resume. Fall back to the default idle
implementation (halt) instead.

Signed-off-by: Thomas Gleixner 
Tested-by: Andrew Morton 
Cc: Len Brown 
Cc: Venkatesh Pallipadi 
Cc: Rafael J. Wysocki 
Signed-off-by: Linus Torvalds

sched: sched_clock_idle_[sleep|wakeup]_event()

2007-08-23T13:18:02+00:00

construct a more or less wall-clock time out of sched_clock(), by
using ACPI-idle's existing knowledge about how much time we spent
idling. This allows the rq clock to work around TSC-stops-in-C2,
TSC-gets-corrupted-in-C3 type of problems.

( Besides the scheduler's statistics this also benefits blktrace and
  printk-timestamps as well. )

Furthermore, the precise before-C2/C3-sleep and after-C2/C3-wakeup
callbacks allow the scheduler to get out the most of the period where
the CPU has a reliable TSC. This results in slightly more precise
task statistics.

the ACPI bits were acked by Len.

Signed-off-by: Ingo Molnar 
Acked-by: Len Brown

ACPI: fix "Time Problems with 2.6.23-rc1-gf695baf2"

2007-08-07T19:25:31+00:00

Enable C3 without bm control only for CST based C3.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Len Brown

Pull misc into release branch

2007-07-22T06:27:40+00:00

Conflicts:

	Documentation/feature-removal-schedule.txt

[IA64] Convert to generic timekeeping/clocksource

2007-07-20T18:22:30+00:00

This is a merge of Peter Keilty's initial patch (which was
revived by Bob Picco) for this with Hidetoshi Seto's fixes
and scaling improvements.

Acked-by: Bob Picco 
Signed-off-by: Tony Luck

ACPI: Enable C3 even when PM2_control is zero

2007-07-19T01:43:21+00:00

On systems that do not have pm2_control_block, we cannot really use
ARB_DISABLE before C3. We used to disable C3 totally on such systems.

To be compatible with Windows, we need to enable C3 on such systems now.
We just skip ARB_DISABLE step before entering the C3-state and assume
hardware is handling things correctly. Also, ACPI spec is not clear
about pm2_control is _needed_ for C3 or not.

We have atleast one system that need this to enable C3.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Len Brown

ACPI: fix 2.6.20 SMP boot regression

2007-06-23T14:57:28+00:00

Always disable/enable interrupts in the acpi idle routine,
even in the error path.

This is required as the 2.6.20 change in git commit d331e739f5ad2aaa9...
"Fix interrupt race in idle callback" expects the idle handler
to enable interrupt before returning.

There was a case in acpi idle routine, in which interrupt was not being
enabled before return, which caused the system to hang at bootup, while
enabling C-states on an SMP system.

The signature of the hang was that "processor.nocst"
was required to enable boot.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Len Brown

[PATCH] x86: Log reason why TSC was marked unstable

2007-05-02T17:27:08+00:00

Change mark_tsc_unstable() so it takes a string argument, which holds the
reason the TSC was marked unstable.

This is then displayed the first time mark_tsc_unstable is called.

This should help us better debug why the TSC was marked unstable on certain
systems and allow us to make sure we're not being overly paranoid when
throwing out this troublesome clocksource.

Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Andi Kleen

ACPI: remove duplicate include

2007-04-25T18:12:00+00:00

Thomas's patch for including  for x86 UP builds came into
Linus's tree from two different directions, both of which were merged.
This reverts the latter, yanking out the duplicate #include and comment.

Signed-off-by: Ray Lee 
Signed-off-by: Andrew Morton 
Signed-off-by: Len Brown

[PATCH] i386: add command line option "local_apic_timer_c2_ok"

2007-03-23T17:21:02+00:00

It turned out that it is almost impossible to trust ACPI, BIOS & Co.
regarding the C states. This was the reason to switch the local apic
timer off in C2 state already. OTOH there are sane and well behaving
systems, which get punished by that decision.

Allow the user to confirm that the local apic timer is trustworthy in C2
state. This keeps the default behaviour on the safe side.

Signed-off-by: Thomas Gleixner 
Acked-by: Ingo Molnar 
Signed-off-by: Linus Torvalds