* KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote: > > > On Tue, 2009-05-12 at 19:01 +0900, KOSAKI Motohiro wrote: > > > > +#ifdef CONFIGCONFIG_SMP > > > > > > typo ? > > > > yes, this week is my memorial stupid one ;) > > ok, assemble list indicate current patch have no typo ;) > > ffffffff814ae920: 48 c7 40 30 10 eb 2a movq $0xffffffff812aeb10,0x30(%rax) > ffffffff814ae927: 81 > ffffffff814ae928: c7 05 3e 37 fe ff 01 movl $0x1,-0x1c8c2(%rip) # ffffffff81492070 <scheduler_running> > ffffffff814ae92f: 00 00 00 > ffffffff814ae932: 8b 05 28 52 fe ff mov -0x1add8(%rip),%eax # ffffffff81493b60 <percpu_counter_batch> > ffffffff814ae938: 89 05 36 37 fe ff mov %eax,-0x1c8ca(%rip) # ffffffff81492074 <cpuacct_batch> > ffffffff814ae93e: 41 5c pop %r12 > > > > --------------------------------------------------------- > Subject: [PATCH] cpuacct: Use bigger percpu counter batch values for stats counters on archs that have VIRT_CPU_ACCOUNTING=y > > percpu counters used to accumulate statistics in cpuacct controller use > the default batch value [max(2*nr_cpus, 32)] which can be too small for > archs that define VIRT_CPU_ACCOUNTING. In such archs, a tick could result in > cputime updates in the range of thousands. As a result, cpuacct_update_stats() > would end up acquiring the percpu counter spinlock on every tick which > is not good for performance. > > Let those architectures to have a bigger batch threshold so that percpu counter > spinlock isn't taken on every tick. This change doesn't affect the archs which > don't define VIRT_CPU_ACCOUNTING and they continue to have the default > percpu counter batch value. > > Cc: Balaji Rao <balajirrao@xxxxxxxxx> > Cc: Dhaval Giani <dhaval@xxxxxxxxxxxxxxxxxx> > Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> > Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> > Cc: Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxx> > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > Signed-off-by: Bharata B Rao <bharata@xxxxxxxxxxxxxxxxxx> > Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > --- > kernel/sched.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) Please reuse the commit log formatting fixes i did when i applied your patch. (you should still have that commit notification email) Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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