On Mon, Aug 12, 2019 at 05:52:04AM -0700 tip-bot for Phil Auld wrote: > Commit-ID: a46d14eca7b75fffe35603aa8b81df654353d80f > Gitweb: > https://git.kernel.org/tip/a46d14eca7b75fffe35603aa8b81df654353d80f > Author: Phil Auld <pa...@redhat.com> > AuthorDate: Thu, 1 Aug 2019 09:37:49 -0400 > Committer: Thomas Gleixner <t...@linutronix.de> > CommitDate: Mon, 12 Aug 2019 14:45:34 +0200 > > sched/fair: Use rq_lock/unlock in online_fair_sched_group > > Enabling WARN_DOUBLE_CLOCK in /sys/kernel/debug/sched_features causes > warning to fire in update_rq_clock. This seems to be caused by onlining > a new fair sched group not using the rq lock wrappers. > > [] rq->clock_update_flags & RQCF_UPDATED > [] WARNING: CPU: 5 PID: 54385 at kernel/sched/core.c:210 > update_rq_clock+0xec/0x150 > > [] Call Trace: > [] online_fair_sched_group+0x53/0x100 > [] cpu_cgroup_css_online+0x16/0x20 > [] online_css+0x1c/0x60 > [] cgroup_apply_control_enable+0x231/0x3b0 > [] cgroup_mkdir+0x41b/0x530 > [] kernfs_iop_mkdir+0x61/0xa0 > [] vfs_mkdir+0x108/0x1a0 > [] do_mkdirat+0x77/0xe0 > [] do_syscall_64+0x55/0x1d0 > [] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Using the wrappers in online_fair_sched_group instead of the raw locking > removes this warning. > > [ tglx: Use rq_*lock_irq() ] > > Signed-off-by: Phil Auld <pa...@redhat.com> > Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> > Signed-off-by: Thomas Gleixner <t...@linutronix.de> > Cc: Ingo Molnar <mi...@redhat.com> > Cc: Vincent Guittot <vincent.guit...@linaro.org> > Cc: Ingo Molnar <mi...@kernel.org> > Link: https://lkml.kernel.org/r/20190801133749.11033-1-pa...@redhat.com > --- > kernel/sched/fair.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 19c58599e967..1054d2cf6aaa 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -10281,18 +10281,18 @@ err: > void online_fair_sched_group(struct task_group *tg) > { > struct sched_entity *se; > + struct rq_flags rf; > struct rq *rq; > int i; > > for_each_possible_cpu(i) { > rq = cpu_rq(i); > se = tg->se[i]; > - > - raw_spin_lock_irq(&rq->lock); > + rq_lock_irq(rq, &rf); > update_rq_clock(rq); > attach_entity_cfs_rq(se); > sync_throttle(tg, i); > - raw_spin_unlock_irq(&rq->lock); > + rq_unlock_irq(rq, &rf); > } > } >
Thanks Thomas! --
