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 /include/linux/jump_label.h | |
| 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 'include/linux/jump_label.h')
| -rw-r--r-- | include/linux/jump_label.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 3b7675bcca64..cd0d2270998f 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -160,6 +160,8 @@ extern void arch_jump_label_transform_static(struct jump_entry *entry, extern int jump_label_text_reserved(void *start, void *end); extern void static_key_slow_inc(struct static_key *key); extern void static_key_slow_dec(struct static_key *key); +extern void static_key_slow_inc_cpuslocked(struct static_key *key); +extern void static_key_slow_dec_cpuslocked(struct static_key *key); extern void jump_label_apply_nops(struct module *mod); extern int static_key_count(struct static_key *key); extern void static_key_enable(struct static_key *key); @@ -222,6 +224,9 @@ static inline void static_key_slow_dec(struct static_key *key) atomic_dec(&key->enabled); } +#define static_key_slow_inc_cpuslocked(key) static_key_slow_inc(key) +#define static_key_slow_dec_cpuslocked(key) static_key_slow_dec(key) + static inline int jump_label_text_reserved(void *start, void *end) { return 0; @@ -416,6 +421,8 @@ extern bool ____wrong_branch_error(void); #define static_branch_inc(x) static_key_slow_inc(&(x)->key) #define static_branch_dec(x) static_key_slow_dec(&(x)->key) +#define static_branch_inc_cpuslocked(x) static_key_slow_inc_cpuslocked(&(x)->key) +#define static_branch_dec_cpuslocked(x) static_key_slow_dec_cpuslocked(&(x)->key) /* * Normal usage; boolean enable/disable. |