diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2025-07-15 15:11:14 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-15 12:14:03 +0200 |
| commit | 3df959fd51d6b58805f15f21b78ba57bf6b07dfc (patch) | |
| tree | 67b2af4e6c6e2748d6b359b1f85fdeafa60a79c1 | |
| parent | c4a0d62bbe9914463c6b7b6a2769efd4701c9596 (diff) | |
sched/psi: Fix psi_seq initialization
[ Upstream commit 99b773d720aeea1ef2170dce5fcfa80649e26b78 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.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 81cfefc4d892..7d0f8fdd48a3 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -172,7 +172,7 @@ 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) { @@ -200,11 +200,7 @@ 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); |