On Sat, 15 Sep 2018 at 14:30, Ingo Molnar <mingo@xxxxxxxxxx> wrote: > > > * Vincent Guittot <vincent.guittot@xxxxxxxxxx> wrote: > > > Hi Ingo, > > > > On Sat, 15 Sep 2018 at 13:47, Ingo Molnar <mingo@xxxxxxxxxx> wrote: > > > > > > > > > * tip-bot for Vincent Guittot <tipbot@xxxxxxxxx> wrote: > > > > > > > Commit-ID: 2e62c4743adc4c7bfcbc1f45118fc7bec58cf30a > > > > Gitweb: https://git.kernel.org/tip/2e62c4743adc4c7bfcbc1f45118fc7bec58cf30a > > > > Author: Vincent Guittot <vincent.guittot@xxxxxxxxxx> > > > > AuthorDate: Thu, 19 Jul 2018 14:00:06 +0200 > > > > Committer: Ingo Molnar <mingo@xxxxxxxxxx> > > > > CommitDate: Wed, 25 Jul 2018 11:41:05 +0200 > > > > > > > > sched/fair: Remove #ifdefs from scale_rt_capacity() > > > > > > > > Reuse cpu_util_irq() that has been defined for schedutil and set irq util > > > > to 0 when !CONFIG_IRQ_TIME_ACCOUNTING. > > > > > > > > But the compiler is not able to optimize the sequence (at least with > > > > aarch64 GCC 7.2.1): > > > > > > > > free *= (max - irq); > > > > free /= max; > > > > > > > > when irq is fixed to 0 > > > > > > > > Add a new inline function scale_irq_capacity() that will scale utilization > > > > when irq is accounted. Reuse this funciton in schedutil which applies > > > > similar formula. > > > > > > > > Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx> > > > > Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx> > > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > > > > Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx> > > > > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > > > Cc: rjw@xxxxxxxxxxxxx > > > > Link: http://lkml.kernel.org/r/1532001606-6689-1-git-send-email-vincent.guittot@xxxxxxxxxx > > > > Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> > > > > --- > > > > kernel/sched/core.c | 2 +- > > > > kernel/sched/cpufreq_schedutil.c | 3 +-- > > > > kernel/sched/fair.c | 13 +++---------- > > > > kernel/sched/sched.h | 20 ++++++++++++++++++-- > > > > 4 files changed, 23 insertions(+), 15 deletions(-) > > > > > > This commit introduced a build warning in the SMP=n case, could we please fix that? (Probably > > > the best to maintain variant would be to mark it as __maybe_unused.) > > > > Dou sent a fix for this warning > > https://lkml.org/lkml/2018/8/10/22 > > This one remove one HAVE_SCHED_AVG_IRQ which is at the opposite of > > what yyou propose below > > Yeah, that's a bad patch because it moves one step back, beyond also having an obvious typo in > the title and overall atrocious spelling that shows that not much thought must have gone into > the patch - yet you acked it, which makes me unhappy as a maintainer: please don't ack > obviously triple-flawed patches! sorry about that > > > and Miguel also made a proposal: > > https://lkml.org/lkml/2018/9/8/215 > > based on __maybe_unused > > That solution is probably better, but: > > > > > > > Also, while at it, there's a number of other places that use this pattern: > > > > > > > -#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) > > > > +#ifdef HAVE_SCHED_AVG_IRQ > > > > > > Could we convert those to HAVE_SCHED_AVG_IRQ as well? > > > > I'm not sure that we can convert all to HAVE_SCHED_AVG_IRQ > > > > > > > > dagon:~/tip> git grep 'defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)' kernel/sched/ > > > kernel/sched/core.c:#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) > > > > we can't replace one because the variables can be used when > > HAVE_SCHED_AVG_IRQ is undefined > > Well, firstly, why is HAVE_SCHED_AVG_IRQ defined in a header and not in the Kconfig space as I > originally suggested? > > Secondly, HAVE_SCHED_AVG_IRQ is defined poorly AFAICS, it should be 0/1 so it can be used as a > replacement pattern in #if sequences - not in #ifdef sequences as your patch did. > > I.e. this needs to be sorted out and done properly, the concerns you voice are simply a side > effect of this having been done badly. Ok. I'm going to prepare a patchset to fix all these points. Regards, Vincent > > Thanks, > > Ingo
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