linux/drivers/acpi
Thomas Gleixner 0a7992c908 acpi: fix bogus preemption logic
The ACPI_PREEMPTION_POINT() logic was introduced in commit 8bd108d
(ACPICA: add preemption point after each opcode parse).  The follow up
commits abe1dfab6, 138d15692, c084ca70 tried to fix the preemption logic
back and forth, but nobody noticed that the usage of
in_atomic_preempt_off() in that context is wrong.

The check which guards the call of cond_resched() is:

    if (!in_atomic_preempt_off() && !irqs_disabled())

in_atomic_preempt_off() is not intended for general use as the comment
above the macro definition clearly says:

 * Check whether we were atomic before we did preempt_disable():
 * (used by the scheduler, *after* releasing the kernel lock)

On a CONFIG_PREEMPT=n kernel the usage of in_atomic_preempt_off() works by
accident, but with CONFIG_PREEMPT=y it's just broken.

The whole purpose of the ACPI_PREEMPTION_POINT() is to reduce the latency
on a CONFIG_PREEMPT=n kernel, so make ACPI_PREEMPTION_POINT() depend on
CONFIG_PREEMPT=n and remove the in_atomic_preempt_off() check.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16210

[akpm@linux-foundation.org: fix build]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Len Brown <lenb@kernel.org>
Cc: Francois Valenduc <francois.valenduc@tvcablenet.be>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-12 08:43:29 -07:00
..
acpica Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-08-07 17:08:30 -07:00
apei acpi: fix bogus preemption logic 2010-08-12 08:43:29 -07:00
Kconfig acpi ec_sys: Be more cautious about ec write access 2010-08-03 09:49:13 -04:00
Makefile ACPI: Provide /sys/kernel/debug/ec/... 2010-08-03 09:49:08 -04:00
ac.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
acpi_memhotplug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
acpi_pad.c time: Kill off CONFIG_GENERIC_TIME 2010-07-27 12:40:54 +02:00
atomicio.c acpi: update gfp/slab.h includes 2010-06-28 10:19:19 +10:00
battery.c ACPI battery: don't invoke power_supply_changed twice when battery is hot-added 2010-07-06 22:22:46 -04:00
blacklist.c ACPI video: fix string mismatch for Sony SR290 laptop 2010-07-06 22:45:18 -04:00
bus.c drivers: acpi: don't use own implementation of hex_to_bin() 2010-05-25 08:07:06 -07:00
button.c ACPICA: Remove wakeup GPE reference counting which is not used 2010-07-06 22:34:26 -04:00
cm_sbs.c ACPI: Move definition of PREFIX from acpi_bus.h to internal..h 2009-08-28 19:57:27 -04:00
container.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
debug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
dock.c Merge branches 'battery', 'bugzilla-14667', 'bugzilla-15096', 'bugzilla-15480', 'bugzilla-15521', 'bugzilla-15605', 'gpe-reference-counters', 'misc', 'pxm-fix' and 'video-random-key' into release 2010-04-06 17:06:22 -04:00
ec.c Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-08-07 17:08:30 -07:00
ec_sys.c acpi ec_sys: Be more cautious about ec write access 2010-08-03 09:49:13 -04:00
event.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
fan.c ACPI: fan: fix unbalanced code block 2010-06-10 11:24:51 -04:00
glue.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
hed.c ACPI Hardware Error Device (PNP0C33) support 2010-05-19 22:40:24 -04:00
internal.h ACPI: Provide /sys/kernel/debug/ec/... 2010-08-03 09:49:08 -04:00
numa.c ACPI: NUMA: map pxms to low node ids 2010-04-04 00:50:01 -04:00
osl.c Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-08-07 17:08:30 -07:00
pci_bind.c PCI / ACPI / PM: Platform support for PCI PME wake-up 2010-02-22 16:21:02 -08:00
pci_irq.c x86, acpi/irq: pci device dev->irq is an isa irq not a gsi 2010-05-04 13:34:30 -07:00
pci_link.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
pci_root.c ACPI: Disable ASPM if the platform won't provide _OSC control for PCIe 2010-07-30 09:29:17 -07:00
pci_slot.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
power.c Merge branch 'master' into for-next 2010-04-23 02:08:44 +02:00
power_meter.c power_meter: acpi_device_class "power_meter_resource" too long 2010-05-06 02:38:24 -04:00
proc.c Fix misspellings of "separate" in strings. 2010-02-04 11:55:46 +01:00
processor_core.c ACPI: processor: fix processor_physically_present on UP 2010-07-12 13:28:34 -04:00
processor_driver.c ACPI: Do not try to set up acpi processor stuff on cores exceeding maxcpus= 2010-06-09 18:04:12 -04:00
processor_idle.c Merge branch 'timers-timekeeping-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 13:18:29 -07:00
processor_perflib.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
processor_thermal.c ACPI: Remove unnecessary cast. 2010-01-15 23:06:44 -05:00
processor_throttling.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
reboot.c
sbs.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
sbshc.c sbshc: acpi_device_class "smbus_host_controller" too long 2010-05-06 02:38:25 -04:00
sbshc.h
scan.c ACPI / ACPICA: Do not execute _PRW methods during initialization 2010-07-12 14:17:39 -04:00
sleep.c Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-08-07 17:08:30 -07:00
sleep.h drivers/acpi/sleep.h: Checkpatch cleanup 2010-05-28 15:31:33 -04:00
system.c ACPICA: Remove wakeup GPE reference counting which is not used 2010-07-06 22:34:26 -04:00
tables.c ACPI: delete the "acpi=ht" boot option 2010-03-14 20:58:38 -04:00
thermal.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
utils.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
video.c Merge branch 'misc-2.6.35' into release 2010-05-28 16:18:20 -04:00
video_detect.c ACPI: video: fix acpi_backlight=video 2010-05-20 01:31:00 -04:00
wakeup.c ACPICA: Introduce acpi_gpe_wakeup() 2010-07-06 22:34:26 -04:00