Chen, Kenneth W 1e185b97b4 [PATCH] ia64: cpu_idle performance bug fix ... Our performance validation on 2.6.15-rc1 caught a disastrous performance regression on ia64 with netperf (-98%) and volanomark (-58%) compares to previous kernel version 2.6.14-git7. See the following chart (result group 1 & 2). http://kernel-perf.sourceforge.net/results.machine_id=26.html We have root caused it to commit 64c7c8f885 This changeset broke the ia64 task resched notification. In sched.c:resched_task(), a reschedule IPI is conditioned upon TIF_POLLING_NRFLAG. However, the above changeset unconditionally set the polling thread flag for idle tasks regardless whether pal_halt_light is in use or not. As a result, resched IPI is not sent from resched_task(). And since the default behavior on ia64 is to use pal_halt_light, we end up delaying the rescheduling task until next timer tick, and thus cause the performance regression. This fixes the performance bug. I'm glad our performance suite is turning up bad performance bug like this in time. Signed-off-by: Ken Chen <kenneth.w.chen@intel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>		2005-11-15 15:50:51 -08:00
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alpha
arm	[ARM] Initialise SA1111 core before SA1111 PCMCIA	2005-11-15 19:04:22 +00:00
arm26
cris
frv
h8300
i386	[PATCH] drop "[PATCH] i386 kexec-on-panic: Don't shutdown the apics"	2005-11-15 08:59:18 -08:00
ia64	[PATCH] ia64: cpu_idle performance bug fix	2005-11-15 15:50:51 -08:00
m32r
m68k	[PATCH] m68k: convert thread flags to use bit fields	2005-11-13 18:14:14 -08:00
m68knommu
mips	[PATCH] arch/mips/au1000/common/usbdev.c: don't concatenate __FUNCTION__ with strings	2005-11-13 18:14:16 -08:00
parisc
powerpc	[PATCH] Add missing EXPORT_SYMBOLS() for __ide_mm_* functions on powerpc	2005-11-15 08:59:19 -08:00
ppc
ppc64	powerpc: Move most remaining ppc64 files over to arch/powerpc	2005-11-14 17:30:17 +11:00
s390
sh
sh64
sparc	[PATCH] atomic: inc_not_zero	2005-11-13 18:14:16 -08:00
sparc64
um	[PATCH] uml: fix daemon transport exit path bug	2005-11-13 18:14:15 -08:00
v850	[PATCH] v850: use generic hardirq code	2005-11-15 08:59:20 -08:00
x86_64	Merge x86-64 update from Andi	2005-11-14 19:56:02 -08:00
xtensa