diff options
Diffstat (limited to 'debian/patches-rt/0003-hrtimer-Prevent-using-hrtimer_grab_expiry_lock-on-mi.patch')
-rw-r--r-- | debian/patches-rt/0003-hrtimer-Prevent-using-hrtimer_grab_expiry_lock-on-mi.patch | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/debian/patches-rt/0003-hrtimer-Prevent-using-hrtimer_grab_expiry_lock-on-mi.patch b/debian/patches-rt/0003-hrtimer-Prevent-using-hrtimer_grab_expiry_lock-on-mi.patch new file mode 100644 index 000000000..4215cb8ad --- /dev/null +++ b/debian/patches-rt/0003-hrtimer-Prevent-using-hrtimer_grab_expiry_lock-on-mi.patch @@ -0,0 +1,34 @@ +From: Julien Grall <julien.grall@arm.com> +Date: Wed, 21 Aug 2019 10:24:09 +0100 +Subject: [PATCH 3/3] hrtimer: Prevent using hrtimer_grab_expiry_lock() on + migration_base +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.10-rt5.tar.xz + +As tglx puts it: +|If base == migration_base then there is no point to lock soft_expiry_lock +|simply because the timer is not executing the callback in soft irq context +|and the whole lock/unlock dance can be avoided. + +Furthermore, all the path leading to hrtimer_grab_expiry_lock() assumes +timer->base and timer->base->cpu_base are always non-NULL. So it is safe +to remove the NULL checks here. + +Signed-off-by: Julien Grall <julien.grall@arm.com> +Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908211557420.2223@nanos.tec.linutronix.de +[bigeasy: rewrite changelog] +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/time/hrtimer.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/kernel/time/hrtimer.c ++++ b/kernel/time/hrtimer.c +@@ -934,7 +934,7 @@ void hrtimer_grab_expiry_lock(const stru + { + struct hrtimer_clock_base *base = READ_ONCE(timer->base); + +- if (timer->is_soft && base && base->cpu_base) { ++ if (timer->is_soft && base != &migration_base) { + spin_lock(&base->cpu_base->softirq_expiry_lock); + spin_unlock(&base->cpu_base->softirq_expiry_lock); + } |