From: Juri Lelli Date: Fri, 27 Jun 2025 11:51:16 +0000 (+0200) Subject: sched/deadline: Fix accounting after global limits change X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=440989c10f4e32620e9e2717ca52c3ed7ae11048;p=thirdparty%2Fkernel%2Fstable.git sched/deadline: Fix accounting after global limits change A global limits change (sched_rt_handler() logic) currently leaves stale and/or incorrect values in variables related to accounting (e.g. extra_bw). Properly clean up per runqueue variables before implementing the change and rebuild scheduling domains (so that accounting is also properly restored) after such a change is complete. Reported-by: Marcel Ziswiler Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) Tested-by: Marcel Ziswiler # nuc & rock5b Link: https://lore.kernel.org/r/20250627115118.438797-4-juri.lelli@redhat.com --- diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 0abffe3860e3..9c7d9528d5fa 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -3183,6 +3183,9 @@ void sched_dl_do_global(void) if (global_rt_runtime() != RUNTIME_INF) new_bw = to_ratio(global_rt_period(), global_rt_runtime()); + for_each_possible_cpu(cpu) + init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); + for_each_possible_cpu(cpu) { rcu_read_lock_sched(); @@ -3198,7 +3201,6 @@ void sched_dl_do_global(void) raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); - init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); } } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 15d5855c542c..be6e9bcbe82b 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2886,6 +2886,12 @@ undo: sched_domains_mutex_unlock(); mutex_unlock(&mutex); + /* + * After changing maximum available bandwidth for DEADLINE, we need to + * recompute per root domain and per cpus variables accordingly. + */ + rebuild_sched_domains(); + return ret; }