diff options
| author |   Peter Zijlstra <peterz@infradead.org> | 2025-07-15 15:11:14 -0400 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2025-08-04 10:51:22 -0700 |
| commit | 99b773d720aeea1ef2170dce5fcfa80649e26b78 (patch) | |
| tree | c1fbd6207ee56317e27dd806fcc139735cc91fc9 | |
| parent | Merge tag 'for-6.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm (diff) | |
| download | wireguard-linux-99b773d720aeea1ef2170dce5fcfa80649e26b78.tar.xz wireguard-linux-99b773d720aeea1ef2170dce5fcfa80649e26b78.zip | |
sched/psi: Fix psi_seq initialization
With the seqcount moved out of the group into a global psi_seq,
re-initializing the seqcount on group creation is causing seqcount
corruption.
Fixes: 570c8efd5eb7 ("sched/psi: Optimize psi_group_change() cpu_clock() usage")
Reported-by: Chris Mason <clm@meta.com>
Suggested-by: Beata Michalska <beata.michalska@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | kernel/sched/psi.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 2024c1d36402..59fdb7ebbf22 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -176,7 +176,7 @@ struct psi_group psi_system = { .pcpu = &system_group_pcpu, }; -static DEFINE_PER_CPU(seqcount_t, psi_seq); +static DEFINE_PER_CPU(seqcount_t, psi_seq) = SEQCNT_ZERO(psi_seq); static inline void psi_write_begin(int cpu) { @@ -204,11 +204,7 @@ static void poll_timer_fn(struct timer_list *t); static void group_init(struct psi_group *group) { - int cpu; - group->enabled = true; - for_each_possible_cpu(cpu) - seqcount_init(per_cpu_ptr(&psi_seq, cpu)); group->avg_last_update = sched_clock(); group->avg_next_update = group->avg_last_update + psi_period; mutex_init(&group->avgs_lock); |