diff options
| -rw-r--r-- | patches/kernel-hrtimer-hotplug-don-t-wake-ktimersoftd-while-.patch | 69 | ||||
| -rw-r--r-- | patches/localversion.patch | 2 | ||||
| -rw-r--r-- | patches/series | 1 |
3 files changed, 71 insertions, 1 deletions
diff --git a/patches/kernel-hrtimer-hotplug-don-t-wake-ktimersoftd-while-.patch b/patches/kernel-hrtimer-hotplug-don-t-wake-ktimersoftd-while-.patch new file mode 100644 index 000000000000..925c2af1942e --- /dev/null +++ b/patches/kernel-hrtimer-hotplug-don-t-wake-ktimersoftd-while-.patch @@ -0,0 +1,69 @@ +From 4ca8658769126558b04a1d78b7d6bee389bfa24b Mon Sep 17 00:00:00 2001 +From: Mike Galbraith <efault@gmx.de> +Date: Sun, 3 Sep 2017 04:48:10 +0200 +Subject: [PATCH] kernel/hrtimer/hotplug: don't wake ktimersoftd while holding + the hrtimer base lock + +kernel/hrtimer: don't wakeup a process while holding the hrtimer base lock +missed a path, namely hrtimers_dead_cpu() -> migrate_hrtimer_list(). Defer +raising softirq until after base lock has been released there as well. + +Signed-off-by: Mike Galbraith <efault@gmx.de> +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/time/hrtimer.c | 19 +++++++++++++------ + 1 file changed, 13 insertions(+), 6 deletions(-) + +--- a/kernel/time/hrtimer.c ++++ b/kernel/time/hrtimer.c +@@ -1725,7 +1725,7 @@ int hrtimers_prepare_cpu(unsigned int cp + + #ifdef CONFIG_HOTPLUG_CPU + +-static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, ++static int migrate_hrtimer_list(struct hrtimer_clock_base *old_base, + struct hrtimer_clock_base *new_base) + { + struct hrtimer *timer; +@@ -1755,15 +1755,19 @@ static void migrate_hrtimer_list(struct + } + #ifdef CONFIG_PREEMPT_RT_BASE + list_splice_tail(&old_base->expired, &new_base->expired); +- if (!list_empty(&new_base->expired)) +- raise_softirq_irqoff(HRTIMER_SOFTIRQ); ++ /* ++ * Tell the caller to raise HRTIMER_SOFTIRQ. We can't safely ++ * acquire ktimersoftd->pi_lock while the base lock is held. ++ */ ++ return !list_empty(&new_base->expired); + #endif ++ return 0; + } + + int hrtimers_dead_cpu(unsigned int scpu) + { + struct hrtimer_cpu_base *old_base, *new_base; +- int i; ++ int i, raise = 0; + + BUG_ON(cpu_online(scpu)); + tick_cancel_sched_timer(scpu); +@@ -1779,13 +1783,16 @@ int hrtimers_dead_cpu(unsigned int scpu) + raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING); + + for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { +- migrate_hrtimer_list(&old_base->clock_base[i], +- &new_base->clock_base[i]); ++ raise |= migrate_hrtimer_list(&old_base->clock_base[i], ++ &new_base->clock_base[i]); + } + + raw_spin_unlock(&old_base->lock); + raw_spin_unlock(&new_base->lock); + ++ if (raise) ++ raise_softirq_irqoff(HRTIMER_SOFTIRQ); ++ + /* Check, if we got expired work to do */ + __hrtimer_peek_ahead_timers(); + local_irq_enable(); diff --git a/patches/localversion.patch b/patches/localversion.patch index 58842b503a27..12bd473a33f5 100644 --- a/patches/localversion.patch +++ b/patches/localversion.patch @@ -10,4 +10,4 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- /dev/null +++ b/localversion-rt @@ -0,0 +1 @@ -+-rt11 ++-rt12 diff --git a/patches/series b/patches/series index 8dac6fa0f250..0985cc1292d0 100644 --- a/patches/series +++ b/patches/series @@ -397,6 +397,7 @@ tick-broadcast--Make-hrtimer-irqsafe.patch timer-hrtimer-check-properly-for-a-running-timer.patch kernel-hrtimer-migrate-deferred-timer-on-CPU-down.patch kernel-hrtimer-don-t-wakeup-a-process-while-holding-.patch +kernel-hrtimer-hotplug-don-t-wake-ktimersoftd-while-.patch # POSIX-CPU-TIMERS posix-timers-thread-posix-cpu-timers-on-rt.patch |