diff options
Diffstat (limited to 'debian/patches-rt/0004-cgroup-Acquire-cgroup_rstat_lock-with-enabled-interr.patch')
| -rw-r--r-- | debian/patches-rt/0004-cgroup-Acquire-cgroup_rstat_lock-with-enabled-interr.patch | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/debian/patches-rt/0004-cgroup-Acquire-cgroup_rstat_lock-with-enabled-interr.patch b/debian/patches-rt/0004-cgroup-Acquire-cgroup_rstat_lock-with-enabled-interr.patch new file mode 100644 index 000000000..d75a1b4c5 --- /dev/null +++ b/debian/patches-rt/0004-cgroup-Acquire-cgroup_rstat_lock-with-enabled-interr.patch @@ -0,0 +1,72 @@ +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Fri, 16 Aug 2019 12:49:36 +0200 +Subject: [PATCH 4/4] cgroup: Acquire cgroup_rstat_lock with enabled interrupts +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.4/older/patches-5.4.3-rt1.tar.xz + +There is no need to disable interrupts while cgroup_rstat_lock is +acquired. The lock is never used in-IRQ context so a simple spin_lock() +is enough for synchronisation purpose. + +Acquire cgroup_rstat_lock without disabling interrupts and ensure that +cgroup_rstat_cpu_lock is acquired with disabled interrupts (this one is +acquired in-IRQ context). + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/cgroup/rstat.c | 16 ++++++++-------- + 1 file changed, 8 insertions(+), 8 deletions(-) + +--- a/kernel/cgroup/rstat.c ++++ b/kernel/cgroup/rstat.c +@@ -161,17 +161,17 @@ static void cgroup_rstat_flush_locked(st + cpu); + struct cgroup *pos = NULL; + +- raw_spin_lock(cpu_lock); ++ raw_spin_lock_irq(cpu_lock); + while ((pos = cgroup_rstat_cpu_pop_updated(pos, cgrp, cpu))) + cgroup_base_stat_flush(pos, cpu); + +- raw_spin_unlock(cpu_lock); ++ raw_spin_unlock_irq(cpu_lock); + + if (need_resched() || spin_needbreak(&cgroup_rstat_lock)) { +- spin_unlock_irq(&cgroup_rstat_lock); ++ spin_unlock(&cgroup_rstat_lock); + if (!cond_resched()) + cpu_relax(); +- spin_lock_irq(&cgroup_rstat_lock); ++ spin_lock(&cgroup_rstat_lock); + } + } + } +@@ -193,9 +193,9 @@ void cgroup_rstat_flush(struct cgroup *c + { + might_sleep(); + +- spin_lock_irq(&cgroup_rstat_lock); ++ spin_lock(&cgroup_rstat_lock); + cgroup_rstat_flush_locked(cgrp); +- spin_unlock_irq(&cgroup_rstat_lock); ++ spin_unlock(&cgroup_rstat_lock); + } + + /** +@@ -211,7 +211,7 @@ static void cgroup_rstat_flush_hold(stru + __acquires(&cgroup_rstat_lock) + { + might_sleep(); +- spin_lock_irq(&cgroup_rstat_lock); ++ spin_lock(&cgroup_rstat_lock); + cgroup_rstat_flush_locked(cgrp); + } + +@@ -221,7 +221,7 @@ static void cgroup_rstat_flush_hold(stru + static void cgroup_rstat_flush_release(void) + __releases(&cgroup_rstat_lock) + { +- spin_unlock_irq(&cgroup_rstat_lock); ++ spin_unlock(&cgroup_rstat_lock); + } + + int cgroup_rstat_init(struct cgroup *cgrp) |