From: Thomas Gleixner Date: Tue, 7 Jun 2011 09:19:06 +0200 Subject: [PATCH 110/351] sched: Do not account rcu_preempt_depth on RT in might_sleep() Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=4c33fbefa2d8dbc37a5298a428f24021f34b3285 RT changes the rcu_preempt_depth semantics, so we cannot check for it in might_sleep(). Signed-off-by: Thomas Gleixner --- include/linux/rcupdate.h | 7 +++++++ kernel/sched/core.c | 2 +- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 68cbe111420b..027c58cdbb6e 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -73,6 +73,11 @@ void synchronize_rcu(void); * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. */ #define rcu_preempt_depth() (current->rcu_read_lock_nesting) +#ifndef CONFIG_PREEMPT_RT_FULL +#define sched_rcu_preempt_depth() rcu_preempt_depth() +#else +static inline int sched_rcu_preempt_depth(void) { return 0; } +#endif #else /* #ifdef CONFIG_PREEMPT_RCU */ @@ -96,6 +101,8 @@ static inline int rcu_preempt_depth(void) return 0; } +#define sched_rcu_preempt_depth() rcu_preempt_depth() + #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ /* Internal to kernel */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 165df30aad7b..b375f10ca8f8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6193,7 +6193,7 @@ void __init sched_init(void) #ifdef CONFIG_DEBUG_ATOMIC_SLEEP static inline int preempt_count_equals(int preempt_offset) { - int nested = preempt_count() + rcu_preempt_depth(); + int nested = preempt_count() + sched_rcu_preempt_depth(); return (nested == preempt_offset); }