Prev: [PATCH 0/2] ACPI / ACPICA: GPE reference counting fixes
Next: [PATCH] drivers/mfd: kzalloc doesn't return ERR_PTR
From: Len Brown on 28 May 2010 16:50
Hi Linus,

please pull from:

git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6.git idle-release

The new intel_idle driver provides a method to use an optimized
idle loop on machines without using ACPI.

This will update the files shown below.

thanks!
Len Brown
Intel Open Source Technology Center


ps. individual patches are available on linux-pm(a)lists.linux-foundation.org
and a consolidated plain patch is available here:
http://ftp.kernel.org/pub/linux/kernel/people/lenb/idle/patches/2.6.34/idle-release-2.6.34.diff.gz

MAINTAINERS | 7 +
arch/x86/include/asm/thread_info.h | 4 +-
drivers/Makefile | 2 +-
drivers/acpi/acpi_pad.c | 9 -
drivers/acpi/processor_driver.c | 15 +-
drivers/acpi/processor_idle.c | 28 ++-
drivers/cpuidle/cpuidle.c | 12 +-
drivers/cpuidle/cpuidle.h | 1 -
drivers/cpuidle/driver.c | 16 +-
drivers/cpuidle/sysfs.c | 5 +-
drivers/idle/Kconfig | 11 +
drivers/idle/Makefile | 1 +
drivers/idle/intel_idle.c | 461 ++++++++++++++++++++++++++++++++++++
include/linux/cpuidle.h | 8 +-
14 files changed, 538 insertions(+), 42 deletions(-)
create mode 100755 drivers/idle/intel_idle.c

through these commits:

Len Brown (8):
cpuidle: fail to register if !CONFIG_CPU_IDLE
cpuidle: add cpuidle_unregister_driver() error check
cpuidle: make cpuidle_curr_driver static
ACPI: allow a native cpuidle driver to displace ACPI
sched: clarify commment for TS_POLLING
acpi_pad: uses MONITOR/MWAIT, so it doesn't need to clear TS_POLLING
ACPI: acpi_idle: touch TS_POLLING only in the non-MWAIT case
intel_idle: native hardware cpuidle driver for latest Intel processors

with this log:

commit 2671717265ae6e720a9ba5f13fbec3a718983b65
Author: Len Brown <len.brown(a)intel.com>
Date: Mon Mar 8 14:07:30 2010 -0500

intel_idle: native hardware cpuidle driver for latest Intel processors

This EXPERIMENTAL driver supersedes acpi_idle on
Intel Atom Processors, Intel Core i3/i5/i7 Processors
and associated Intel Xeon processors.

It does not support the Intel Core2 processor or earlier.

For kernels configured with ACPI, CONFIG_INTEL_IDLE=y
allows intel_idle to probe before the ACPI processor driver.
Booting with "intel_idle.max_cstate=0" disables intel_idle
and the system will fall back on ACPI's "acpi_idle".

Typical Linux distributions load ACPI processor module early,
making CONFIG_INTEL_IDLE=m not easily useful on ACPI platforms.

intel_idle probes all processors at module_init time.
Processors that are hot-added later will be limited
to using C1 in idle.

Signed-off-by: Len Brown <len.brown(a)intel.com>

commit 02cf4f9808382af7265cafc33dc86ec5875526aa
Author: Len Brown <len.brown(a)intel.com>
Date: Mon May 24 14:27:44 2010 -0400

ACPI: acpi_idle: touch TS_POLLING only in the non-MWAIT case

commit d306ebc28649b89877a22158fe0076f06cc46f60
(ACPI: Be in TS_POLLING state during mwait based C-state entry)
fixed an important power & performance issue where ACPI c2 and c3 C-states
were clearing TS_POLLING even when using MWAIT (ACPI_STATE_FFH).
That bug had been causing us to receive redundant scheduling interrups
when we had already been woken up by MONITOR/MWAIT.

Following up on that...

In the MWAIT case, we don't have to subsequently
check need_resched(), as that c heck was there
for the TS_POLLING-clearing case.

Note that not only does the cpuidle calling function
already check need_resched() before calling us, the
low-level entry into monitor/mwait calls it twice --
guaranteeing that a write to the trigger address
can not go un-noticed.

Also, in this case, we don't have to set TS_POLLING
when we wake, because we never cleared it.

Signed-off-by: Len Brown <len.brown(a)intel.com>
Acked-by: Venkatesh Pallipadi <venki(a)google.com>

commit a7d27c37533524e23bbdc9ba1d78e3241b7483ea
Author: Len Brown <len.brown(a)intel.com>
Date: Mon May 24 11:41:00 2010 -0400

acpi_pad: uses MONITOR/MWAIT, so it doesn't need to clear TS_POLLING

api_pad exclusively uses MONITOR/MWAIT to sleep in idle,
so it does not need the wakeup IPI during idle sleep
that is provoked by clearing TS_POLLING.

Signed-off-by: Len Brown <len.brown(a)intel.com>
Cc: Shaohua Li <shaohua.li(a)intel.com>

commit e45b7fa23097332508730123ac6d59227e7bd7f8
Author: Len Brown <len.brown(a)intel.com>
Date: Mon May 24 11:34:36 2010 -0400

sched: clarify commment for TS_POLLING

TS_POLLING set tells the scheduler an idle_task will poll
need_resched() to look for work.

TS_POLLING clear tells resched_task() and wake_up_idle_cpu()
that the remote CPU's idle_task is now sleeping in idle,
and thus requires a reschedule interrupt notice work.

Update the description of TS_POLLING to reflect how it works.
"idle task polling need_resched, skip sending interrupt"

Wordsmithing-by: Milton Miller <miltonm(a)bga.com>
Signed-off-by: Len Brown <len.brown(a)intel.com>
Acked-by: Peter Zijlstra <peterz(a)infradead.org>

commit 541adf7cd937b3895c7645406a9b060504df453b
Author: Len Brown <len.brown(a)intel.com>
Date: Sat May 22 17:03:29 2010 -0400

ACPI: allow a native cpuidle driver to displace ACPI

The ACPI driver would fail probe when it found that
another driver had previously registered with cpuidle.

But this is a natural situation, as a native hardware
cpuidle driver should be able to bind instead of ACPI,
and the ACPI processor driver should be able to handle
yielding control of C-states while still handling
P-states and T-states.

Add a KERN_DEBUG line showing when acpi_idle
does successfully register.

Signed-off-by: Len Brown <len.brown(a)intel.com>

commit 752138df0dc2daaae09379c754caeb08c97905dc
Author: Len Brown <len.brown(a)intel.com>
Date: Sat May 22 16:57:26 2010 -0400

cpuidle: make cpuidle_curr_driver static

cpuidle_register_driver() sets cpuidle_curr_driver
cpuidle_unregister_driver() clears cpuidle_curr_driver

We should't expose cpuidle_curr_driver to
potential modification except via these interfaces.
So make it static and create cpuidle_get_driver() to observe it.

Signed-off-by: Len Brown <len.brown(a)intel.com>

commit c0d64cb031c21f163a0ec15cf10844bcf0ceedcf
Author: Len Brown <len.brown(a)intel.com>
Date: Sat May 22 16:34:10 2010 -0400

cpuidle: add cpuidle_unregister_driver() error check

Assure that cpuidle_unregister_driver() will not clobber
the registered driver if unregistered by somebody else.

Signed-off-by: Len Brown <len.brown(a)intel.com>

commit 6b2c676bf32be91f43215d5874c07c1becaba013
Author: Len Brown <len.brown(a)intel.com>
Date: Tue May 11 16:50:52 2010 -0400

cpuidle: fail to register if !CONFIG_CPU_IDLE

Signed-off-by: Len Brown <len.brown(a)intel.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: [PATCH 0/2] ACPI / ACPICA: GPE reference counting fixes
Next: [PATCH] drivers/mfd: kzalloc doesn't return ERR_PTR