Ingo, I saw you sent a pull request to Linus including the commit introduced the warnings,
https://lkml.org/lkml/2019/9/16/309 but seems not yet picked up the fix here, https://lore.kernel.org/lkml/20190903141554.GS2349@hirez.programming.kicks-ass.n et/ On Tue, 2019-09-10 at 16:58 -0400, Qian Cai wrote: > On Tue, 2019-09-03 at 16:15 +0200, Peter Zijlstra wrote: > > On Tue, Sep 03, 2019 at 09:03:26AM -0400, Qian Cai wrote: > > > Ingo or Peter, please take a look at this trivial patch. Still see the > > > warning > > > in linux-next every day. > > > > > > On Tue, 2019-08-20 at 14:40 -0400, Qian Cai wrote: > > > > The linux-next commit "sched/fair: Fix low cpu usage with high > > > > throttling by removing expiration of cpu-local slices" [1] introduced a > > > > few compilation warnings, > > > > > > > > kernel/sched/fair.c: In function '__refill_cfs_bandwidth_runtime': > > > > kernel/sched/fair.c:4365:6: warning: variable 'now' set but not used > > > > [-Wunused-but-set-variable] > > > > kernel/sched/fair.c: In function 'start_cfs_bandwidth': > > > > kernel/sched/fair.c:4992:6: warning: variable 'overrun' set but not used > > > > [-Wunused-but-set-variable] > > > > > > > > Also, __refill_cfs_bandwidth_runtime() does no longer update the > > > > expiration time, so fix the comments accordingly. > > > > > > > > [1] > > > > https://lore.kernel.org/lkml/1558121424-2914-1-git-send-email-chiluk+linux > > > > @indeed.com/ > > > > > > > > Signed-off-by: Qian Cai <c...@lca.pw> > > > > Rewrote the Changelog like so: > > Looks good. I suppose it still need Ingo to pick it up, as today's tip/auto- > latest still show those warnings. > > > > > --- > > Subject: sched/fair: Fix -Wunused-but-set-variable warnings > > From: Qian Cai <c...@lca.pw> > > Date: Tue, 20 Aug 2019 14:40:55 -0400 > > > > Commit de53fd7aedb1 ("sched/fair: Fix low cpu usage with high > > throttling by removing expiration of cpu-local slices") introduced a > > few compilation warnings: > > > > kernel/sched/fair.c: In function '__refill_cfs_bandwidth_runtime': > > kernel/sched/fair.c:4365:6: warning: variable 'now' set but not used > > [-Wunused-but-set-variable] > > kernel/sched/fair.c: In function 'start_cfs_bandwidth': > > kernel/sched/fair.c:4992:6: warning: variable 'overrun' set but not used > > [-Wunused-but-set-variable] > > > > Also, __refill_cfs_bandwidth_runtime() does no longer update the > > expiration time, so fix the comments accordingly. > > > > Fixes: de53fd7aedb1 ("sched/fair: Fix low cpu usage with high throttling by > > removing expiration of cpu-local slices") > > Signed-off-by: Qian Cai <c...@lca.pw> > > Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> > > Reviewed-by: Ben Segall <bseg...@google.com> > > Reviewed-by: Dave Chiluk <chiluk+li...@indeed.com> > > Cc: mi...@redhat.com > > Cc: pa...@redhat.com > > Link: https://lkml.kernel.org/r/1566326455-8038-1-git-send-email-...@lca.pw > > --- > > kernel/sched/fair.c | 19 ++++++------------- > > 1 file changed, 6 insertions(+), 13 deletions(-) > > > > --- a/kernel/sched/fair.c > > +++ b/kernel/sched/fair.c > > @@ -4386,21 +4386,16 @@ static inline u64 sched_cfs_bandwidth_sl > > } > > > > /* > > - * Replenish runtime according to assigned quota and update expiration > > time. > > - * We use sched_clock_cpu directly instead of rq->clock to avoid adding > > - * additional synchronization around rq->lock. > > + * Replenish runtime according to assigned quota. We use sched_clock_cpu > > + * directly instead of rq->clock to avoid adding additional synchronization > > + * around rq->lock. > > * > > * requires cfs_b->lock > > */ > > void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b) > > { > > - u64 now; > > - > > - if (cfs_b->quota == RUNTIME_INF) > > - return; > > - > > - now = sched_clock_cpu(smp_processor_id()); > > - cfs_b->runtime = cfs_b->quota; > > + if (cfs_b->quota != RUNTIME_INF) > > + cfs_b->runtime = cfs_b->quota; > > } > > > > static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) > > @@ -5021,15 +5016,13 @@ static void init_cfs_rq_runtime(struct c > > > > void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b) > > { > > - u64 overrun; > > - > > lockdep_assert_held(&cfs_b->lock); > > > > if (cfs_b->period_active) > > return; > > > > cfs_b->period_active = 1; > > - overrun = hrtimer_forward_now(&cfs_b->period_timer, cfs_b->period); > > + hrtimer_forward_now(&cfs_b->period_timer, cfs_b->period); > > hrtimer_start_expires(&cfs_b->period_timer, HRTIMER_MODE_ABS_PINNED); > > } > >
