diff options
author | Peter Zijlstra <peterz@infradead.org> | 2018-01-22 22:53:28 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-05 19:41:17 +0100 |
commit | e5d981df9a1d3f13dfff083ab0578daedbcd9e8a (patch) | |
tree | 91b388528b45cba3538aee53a5af6f9ed11f7c76 /kernel/sched | |
parent | 72e5a2bdf753f5ba82ea6bfb7706aabc9587d0cb (diff) |
sched/core: Fix cpu.max vs. cpuhotplug deadlock
commit ce48c146495a1a50e48cdbfbfaba3e708be7c07c upstream
Tejun reported the following cpu-hotplug lock (percpu-rwsem) read recursion:
tg_set_cfs_bandwidth()
get_online_cpus()
cpus_read_lock()
cfs_bandwidth_usage_inc()
static_key_slow_inc()
cpus_read_lock()
Reported-by: Tejun Heo <tj@kernel.org>
Tested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180122215328.GP3397@worktop
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/sched')
-rw-r--r-- | kernel/sched/fair.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 2d4d79420e36..7240bb4a4090 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4040,12 +4040,12 @@ static inline bool cfs_bandwidth_used(void) void cfs_bandwidth_usage_inc(void) { - static_key_slow_inc(&__cfs_bandwidth_used); + static_key_slow_inc_cpuslocked(&__cfs_bandwidth_used); } void cfs_bandwidth_usage_dec(void) { - static_key_slow_dec(&__cfs_bandwidth_used); + static_key_slow_dec_cpuslocked(&__cfs_bandwidth_used); } #else /* HAVE_JUMP_LABEL */ static bool cfs_bandwidth_used(void) |