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authorDaniel Vetter <daniel.vetter@ffwll.ch>2021-12-14 09:43:25 +0100
committerDaniel Vetter <daniel.vetter@ffwll.ch>2021-12-14 10:24:28 +0100
commit99b03ca651f1c409d296d6c6e9440d9b005c722f (patch)
tree8773b8cbab631258b561ddb3d9b219072095bee4 /arch/x86/kernel/tsc_sync.c
parent211b4dbc070090b4183d6f9db7dd3bd4e6170447 (diff)
parent2585cf9dfaaddf00b069673f27bb3f8530e2039c (diff)
Merge v5.16-rc5 into drm-next
Thomas Zimmermann requested a fixes backmerge, specifically also for 96c5f82ef0a1 ("drm/vc4: fix error code in vc4_create_object()") Just a bunch of adjacent changes conflicts, even the big pile of them in vc4. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'arch/x86/kernel/tsc_sync.c')
-rw-r--r--arch/x86/kernel/tsc_sync.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 50a4515fe0ad..9452dc9664b5 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -30,6 +30,7 @@ struct tsc_adjust {
};
static DEFINE_PER_CPU(struct tsc_adjust, tsc_adjust);
+static struct timer_list tsc_sync_check_timer;
/*
* TSC's on different sockets may be reset asynchronously.
@@ -77,6 +78,46 @@ void tsc_verify_tsc_adjust(bool resume)
}
}
+/*
+ * Normally the tsc_sync will be checked every time system enters idle
+ * state, but there is still caveat that a system won't enter idle,
+ * either because it's too busy or configured purposely to not enter
+ * idle.
+ *
+ * So setup a periodic timer (every 10 minutes) to make sure the check
+ * is always on.
+ */
+
+#define SYNC_CHECK_INTERVAL (HZ * 600)
+
+static void tsc_sync_check_timer_fn(struct timer_list *unused)
+{
+ int next_cpu;
+
+ tsc_verify_tsc_adjust(false);
+
+ /* Run the check for all onlined CPUs in turn */
+ next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
+ if (next_cpu >= nr_cpu_ids)
+ next_cpu = cpumask_first(cpu_online_mask);
+
+ tsc_sync_check_timer.expires += SYNC_CHECK_INTERVAL;
+ add_timer_on(&tsc_sync_check_timer, next_cpu);
+}
+
+static int __init start_sync_check_timer(void)
+{
+ if (!cpu_feature_enabled(X86_FEATURE_TSC_ADJUST) || tsc_clocksource_reliable)
+ return 0;
+
+ timer_setup(&tsc_sync_check_timer, tsc_sync_check_timer_fn, 0);
+ tsc_sync_check_timer.expires = jiffies + SYNC_CHECK_INTERVAL;
+ add_timer(&tsc_sync_check_timer);
+
+ return 0;
+}
+late_initcall(start_sync_check_timer);
+
static void tsc_sanitize_first_cpu(struct tsc_adjust *cur, s64 bootval,
unsigned int cpu, bool bootcpu)
{