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-rw-r--r--libre/linux-libre/0003-tick-Detect-and-fix-jiffies-update-stall.patch86
1 files changed, 0 insertions, 86 deletions
diff --git a/libre/linux-libre/0003-tick-Detect-and-fix-jiffies-update-stall.patch b/libre/linux-libre/0003-tick-Detect-and-fix-jiffies-update-stall.patch
deleted file mode 100644
index b0962dc75..000000000
--- a/libre/linux-libre/0003-tick-Detect-and-fix-jiffies-update-stall.patch
+++ /dev/null
@@ -1,86 +0,0 @@
-From 725479ba08eb2f1da6eec1b23852c1c70e002ed1 Mon Sep 17 00:00:00 2001
-From: Frederic Weisbecker <frederic@kernel.org>
-Date: Wed, 2 Feb 2022 01:01:07 +0100
-Subject: [PATCH 3/7] tick: Detect and fix jiffies update stall
-
-On some rare cases, the timekeeper CPU may be delaying its jiffies
-update duty for a while. Known causes include:
-
-* The timekeeper is waiting on stop_machine in a MULTI_STOP_DISABLE_IRQ
- or MULTI_STOP_RUN state. Disabled interrupts prevent from timekeeping
- updates while waiting for the target CPU to complete its
- stop_machine() callback.
-
-* The timekeeper vcpu has VMEXIT'ed for a long while due to some overload
- on the host.
-
-Detect and fix these situations with emergency timekeeping catchups.
-
-Original-patch-by: Paul E. McKenney <paulmck@kernel.org>
-Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
-Cc: Thomas Gleixner <tglx@linutronix.de>
----
- kernel/time/tick-sched.c | 17 +++++++++++++++++
- kernel/time/tick-sched.h | 4 ++++
- 2 files changed, 21 insertions(+)
-
-diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
-index 5e80ee44c32a..0578c9301b17 100644
---- a/kernel/time/tick-sched.c
-+++ b/kernel/time/tick-sched.c
-@@ -169,6 +169,8 @@ static ktime_t tick_init_jiffy_update(void)
- return period;
- }
-
-+#define MAX_STALLED_JIFFIES 5
-+
- static void tick_sched_do_timer(struct tick_sched *ts, ktime_t now)
- {
- int cpu = smp_processor_id();
-@@ -196,6 +198,21 @@ static void tick_sched_do_timer(struct tick_sched *ts, ktime_t now)
- if (tick_do_timer_cpu == cpu)
- tick_do_update_jiffies64(now);
-
-+ /*
-+ * If jiffies update stalled for too long (timekeeper in stop_machine()
-+ * or VMEXIT'ed for several msecs), force an update.
-+ */
-+ if (ts->last_tick_jiffies != jiffies) {
-+ ts->stalled_jiffies = 0;
-+ ts->last_tick_jiffies = READ_ONCE(jiffies);
-+ } else {
-+ if (++ts->stalled_jiffies == MAX_STALLED_JIFFIES) {
-+ tick_do_update_jiffies64(now);
-+ ts->stalled_jiffies = 0;
-+ ts->last_tick_jiffies = READ_ONCE(jiffies);
-+ }
-+ }
-+
- if (ts->inidle)
- ts->got_idle_tick = 1;
- }
-diff --git a/kernel/time/tick-sched.h b/kernel/time/tick-sched.h
-index d952ae393423..504649513399 100644
---- a/kernel/time/tick-sched.h
-+++ b/kernel/time/tick-sched.h
-@@ -49,6 +49,8 @@ enum tick_nohz_mode {
- * @timer_expires_base: Base time clock monotonic for @timer_expires
- * @next_timer: Expiry time of next expiring timer for debugging purpose only
- * @tick_dep_mask: Tick dependency mask - is set, if someone needs the tick
-+ * @last_tick_jiffies: Value of jiffies seen on last tick
-+ * @stalled_jiffies: Number of stalled jiffies detected across ticks
- */
- struct tick_sched {
- struct hrtimer sched_timer;
-@@ -77,6 +79,8 @@ struct tick_sched {
- u64 next_timer;
- ktime_t idle_expires;
- atomic_t tick_dep_mask;
-+ unsigned long last_tick_jiffies;
-+ unsigned int stalled_jiffies;
- };
-
- extern struct tick_sched *tick_get_tick_sched(int cpu);
---
-2.36.1
-