Peter Zijlstra 2ebd26f64a sched: Cure more NO_HZ load average woes ... commit 0f004f5a69 upstream. There's a long-running regression that proved difficult to fix and which is hitting certain people and is rather annoying in its effects. Damien reported that after 74f5187ac8 (sched: Cure load average vs NO_HZ woes) his load average is unnaturally high, he also noted that even with that patch reverted the load avgerage numbers are not correct. The problem is that the previous patch only solved half the NO_HZ problem, it addressed the part of going into NO_HZ mode, not of comming out of NO_HZ mode. This patch implements that missing half. When comming out of NO_HZ mode there are two important things to take care of: - Folding the pending idle delta into the global active count. - Correctly aging the averages for the idle-duration. So with this patch the NO_HZ interaction should be complete and behaviour between CONFIG_NO_HZ=[yn] should be equivalent. Furthermore, this patch slightly changes the load average computation by adding a rounding term to the fixed point multiplication. Reported-by: Damien Wyart <damien.wyart@free.fr> Reported-by: Tim McGrath <tmhikaru@gmail.com> Tested-by: Damien Wyart <damien.wyart@free.fr> Tested-by: Orion Poplawski <orion@cora.nwra.com> Tested-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Chase Douglas <chase.douglas@canonical.com> LKML-Reference: <1291129145.32004.874.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>		2011-01-07 13:58:31 -08:00
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acpi	ACPI: Fix typos	2010-09-28 21:38:19 -04:00
asm-generic	gpio: doc updates	2010-09-09 18:57:24 -07:00
crypto
drm	drm/ttm: Fix two race conditions + fix busy codepaths	2010-10-06 09:04:43 +10:00
keys
linux	sched: Cure more NO_HZ load average woes	2011-01-07 13:58:31 -08:00
math-emu
media	V4L/DVB: videobuf-dma-sg: set correct size in last sg element	2010-09-27 22:22:01 -03:00
mtd	mtd: Update copyright notices	2010-08-08 20:58:20 +01:00
net	filter: fix sk_filter rcu handling	2011-01-07 13:58:27 -08:00
pcmcia
rdma
rxrpc
scsi	scsi: use __uX types for headers exported to user space	2010-08-11 08:59:01 -07:00
sound	ALSA: emu10k1 - delay the PCM interrupts (add pcm_irq_delay parameter)	2010-08-18 15:10:59 +02:00
trace	Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-08-24 12:21:49 -07:00
video	include: replace unifdef-y with header-y	2010-08-14 22:26:51 +02:00
xen	xen: Provide a variant of __RING_SIZE() that is an integer constant expression	2011-01-07 13:58:31 -08:00
Kbuild