diff options
| author | Juri Lelli <juri.lelli@redhat.com> | 2025-06-27 13:51:15 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-15 16:38:46 +0200 |
| commit | 2e8ebc49deb11cca4e407c144d02b53518852d6f (patch) | |
| tree | 2a2966202b7b1bf8317b37e8bbd0ab8c0ec5db13 | |
| parent | d59d49af4aeed9a81e673e37c26c6a3bacf1a181 (diff) | |
sched/deadline: Reset extra_bw to max_bw when clearing root domains
[ Upstream commit fcc9276c4d331cd1fe9319d793e80b02e09727f5 ]
dl_clear_root_domain() doesn't take into account the fact that per-rq
extra_bw variables retain values computed before root domain changes,
resulting in broken accounting.
Fix it by resetting extra_bw to max_bw before restoring back dl-servers
contributions.
Fixes: 2ff899e351643 ("sched/deadline: Rebuild root domain accounting after every update")
Reported-by: Marcel Ziswiler <marcel.ziswiler@codethink.co.uk>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Marcel Ziswiler <marcel.ziswiler@codethink.co.uk> # nuc & rock5b
Link: https://lore.kernel.org/r/20250627115118.438797-3-juri.lelli@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | kernel/sched/deadline.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 89019a140826..65f3b2cc891d 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -2976,7 +2976,14 @@ void dl_clear_root_domain(struct root_domain *rd) int i; guard(raw_spinlock_irqsave)(&rd->dl_bw.lock); + + /* + * Reset total_bw to zero and extra_bw to max_bw so that next + * loop will add dl-servers contributions back properly, + */ rd->dl_bw.total_bw = 0; + for_each_cpu(i, rd->span) + cpu_rq(i)->dl.extra_bw = cpu_rq(i)->dl.max_bw; /* * dl_servers are not tasks. Since dl_add_task_root_domain ignores |