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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-12 04:24:45 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-12 04:24:45 +0300 |
| commit | daadb3bd0e8d3e317e36bc2c1542e86c528665e5 (patch) | |
| tree | eed975e96b821d903ea57554af25cc5aa76efa24 /include/linux/sched.h | |
| parent | 6ae71436cda740148640046d58190a5bbc3ac86d (diff) | |
| parent | f16cc980d649e664b8f41e1bbaba50255d24e5d1 (diff) | |
| download | linux-daadb3bd0e8d3e317e36bc2c1542e86c528665e5.tar.xz | |
Merge tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Borislav Petkov:
"Lots of cleanups and preparation. Highlights:
- futex: Cleanup and remove runtime futex_cmpxchg detection
- rtmutex: Some fixes for the PREEMPT_RT locking infrastructure
- kcsan: Share owner_on_cpu() between mutex,rtmutex and rwsem and
annotate the racy owner->on_cpu access *once*.
- atomic64: Dead-Code-Elemination"
[ Description above by Peter Zijlstra ]
* tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomic: atomic64: Remove unusable atomic ops
futex: Fix additional regressions
locking: Allow to include asm/spinlock_types.h from linux/spinlock_types_raw.h
x86/mm: Include spinlock_t definition in pgtable.
locking: Mark racy reads of owner->on_cpu
locking: Make owner_on_cpu() into <linux/sched.h>
lockdep/selftests: Adapt ww-tests for PREEMPT_RT
lockdep/selftests: Skip the softirq related tests on PREEMPT_RT
lockdep/selftests: Unbalanced migrate_disable() & rcu_read_lock().
lockdep/selftests: Avoid using local_lock_{acquire|release}().
lockdep: Remove softirq accounting on PREEMPT_RT.
locking/rtmutex: Add rt_mutex_lock_nest_lock() and rt_mutex_lock_killable().
locking/rtmutex: Squash self-deadlock check for ww_rt_mutex.
locking: Remove rt_rwlock_is_contended().
sched: Trigger warning if ->migration_disabled counter underflows.
futex: Fix sparc32/m68k/nds32 build regression
futex: Remove futex_cmpxchg detection
futex: Ensure futex_atomic_cmpxchg_inatomic() is present
kernel/locking: Use a pointer in ww_mutex_trylock().
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 4d0a12618e3c..7a1f16df66e3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2178,6 +2178,15 @@ extern long sched_getaffinity(pid_t pid, struct cpumask *mask); #endif #ifdef CONFIG_SMP +static inline bool owner_on_cpu(struct task_struct *owner) +{ + /* + * As lock holder preemption issue, we both skip spinning if + * task is not on cpu or its cpu is preempted + */ + return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); +} + /* Returns effective CPU energy utilization, as seen by the scheduler */ unsigned long sched_cpu_util(int cpu, unsigned long max); #endif /* CONFIG_SMP */ |