Commit 5d2295f3 authored Sep 04, 2019 by Sebastian Andrzej Siewior Committed by Thomas Gleixner Sep 05, 2019

hrtimer: Add a missing bracket and hide `migration_base' on !SMP



The recent change to avoid taking the expiry lock when a timer is currently
migrated missed to add a bracket at the end of the if statement leading to
compile errors.  Since that commit the variable `migration_base' is always
used but it is only available on SMP configuration thus leading to another
compile error.  The changelog says "The timer base and base->cpu_base
cannot be NULL in the code path", so it is safe to limit this check to SMP
configurations only.

Add the missing bracket to the if statement and hide `migration_base'
behind CONFIG_SMP bars.

[ tglx: Mark the functions inline ... ]

Fixes: 68b2c8c1 ("hrtimer: Don't take expiry_lock when timer is currently migrated")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190904145527.eah7z56ntwobqm6j@linutronix.de

parent a2ed4fd6

kernel/time/hrtimer.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -140,6 +140,11 @@ static struct hrtimer_cpu_base migration_cpu_base = {

		#define migration_base migration_cpu_base.clock_base[0]

		static inline bool is_migration_base(struct hrtimer_clock_base *base)
		{
		return base == &migration_base;
		}

		/*
		* We are using hashed locking: holding per_cpu(hrtimer_bases)[n].lock
		* means that all timers which are tied to this base via timer->base are
		@@ -264,6 +269,11 @@ again:

		#else /* CONFIG_SMP */

		static inline bool is_migration_base(struct hrtimer_clock_base *base)
		{
		return false;
		}

		static inline struct hrtimer_clock_base *
		lock_hrtimer_base(const struct hrtimer timer, unsigned long flags)
		{
		@@ -1221,7 +1231,7 @@ void hrtimer_cancel_wait_running(const struct hrtimer *timer)
		* Just relax if the timer expires in hard interrupt context or if
		* it is currently on the migration base.
		*/
		if (!timer->is_soft \|\| base == &migration_base)
		if (!timer->is_soft \|\| is_migration_base(base)) {
		cpu_relax();
		return;
		}

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