Instead of checking sched_clock_stable from the nohz subsystem to verify
its tick dependency, migrate it to the new mask in order to include it
to the all-in-one check.
Cc: Christoph Lameter <c...@linux.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Preeti U Murthy <pre...@linux.vnet.ibm.com>
Cc: Rik van Riel <r...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Viresh Kumar <viresh.ku...@linaro.org>
Signed-off-by: Frederic Weisbecker <fweis...@gmail.com>
---
kernel/sched/clock.c | 5 +++++
kernel/time/tick-sched.c | 26 ++++++--------------------
2 files changed, 11 insertions(+), 20 deletions(-)
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index c0a2051..30e2524 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -61,6 +61,7 @@
#include <linux/static_key.h>
#include <linux/workqueue.h>
#include <linux/compiler.h>
+#include <linux/tick.h>
/*
* Scheduler clock - returns current time in nanosec units.
@@ -89,6 +90,8 @@ static void __set_sched_clock_stable(void)
{
if (!sched_clock_stable())
static_key_slow_inc(&__sched_clock_stable);
+
+ tick_nohz_clear_tick_dependency(TICK_CLOCK_UNSTABLE_BIT);
}
void set_sched_clock_stable(void)
@@ -108,6 +111,8 @@ static void __clear_sched_clock_stable(struct work_struct
*work)
/* XXX worry about clock continuity */
if (sched_clock_stable())
static_key_slow_dec(&__sched_clock_stable);
+
+ tick_nohz_set_tick_dependency(TICK_CLOCK_UNSTABLE_BIT);
}
static DECLARE_WORK(sched_clock_work, __clear_sched_clock_stable);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 4805f4e..7b74b93 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -174,8 +174,13 @@ static void trace_tick_dependency(unsigned long dep)
return;
}
- if (dep & TICK_CLOCK_UNSTABLE_MASK)
+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+ if (dep & TICK_CLOCK_UNSTABLE_MASK) {
trace_tick_stop(0, "unstable sched clock\n");
+ WARN_ONCE(tick_nohz_full_running,
+ "NO_HZ FULL will not work with unstable sched clock");
+ }
+#endif
}
static bool can_stop_full_tick(struct tick_sched *ts)
@@ -192,25 +197,6 @@ static bool can_stop_full_tick(struct tick_sched *ts)
return false;
}
-#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
- /*
- * sched_clock_tick() needs us?
- *
- * TODO: kick full dynticks CPUs when
- * sched_clock_stable is set.
- */
- if (!sched_clock_stable()) {
- trace_tick_stop(0, "unstable sched clock\n");
- /*
- * Don't allow the user to think they can get
- * full NO_HZ with this machine.
- */
- WARN_ONCE(tick_nohz_full_running,
- "NO_HZ FULL will not work with unstable sched clock");
- return false;
- }
-#endif
-
return true;
}
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
