diff options
| author |   Thomas Gleixner <tglx@linutronix.de> | 2021-09-23 18:54:35 +0200 |
|---|---|---|
| committer |   Peter Zijlstra <peterz@infradead.org> | 2021-10-01 13:57:49 +0200 |
| commit | 874f670e6088d3bff3972ecd44c1cb00610f9183 (patch) | |
| tree | ec4a3568328504f71947fdb4aa27133ed6e4a675 /include/linux/kernel.h | |
| parent | locking/ww-mutex: Fix uninitialized use of ret in test_aa() (diff) | |
| download | linux-dev-874f670e6088d3bff3972ecd44c1cb00610f9183.tar.xz linux-dev-874f670e6088d3bff3972ecd44c1cb00610f9183.zip | |
sched: Clean up the might_sleep() underscore zoo
__might_sleep() vs. ___might_sleep() is hard to distinguish. Aside of that
the three underscore variant is exposed to provide a checkpoint for
rescheduling points which are distinct from blocking points.
They are semantically a preemption point which means that scheduling is
state preserving. A real blocking operation, e.g. mutex_lock(), wait*(),
which cannot preserve a task state which is not equal to RUNNING.
While technically blocking on a "sleeping" spinlock in RT enabled kernels
falls into the voluntary scheduling category because it has to wait until
the contended spin/rw lock becomes available, the RT lock substitution code
can semantically be mapped to a voluntary preemption because the RT lock
substitution code and the scheduler are providing mechanisms to preserve
the task state and to take regular non-lock related wakeups into account.
Rename ___might_sleep() to __might_resched() to make the distinction of
these functions clear.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210923165357.928693482@linutronix.de
Diffstat (limited to 'include/linux/kernel.h')
| -rw-r--r-- | include/linux/kernel.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 2776423a587e..5e4ae54da73e 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -111,7 +111,7 @@ static __always_inline void might_resched(void) #endif /* CONFIG_PREEMPT_* */ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP -extern void ___might_sleep(const char *file, int line, int preempt_offset); +extern void __might_resched(const char *file, int line, int preempt_offset); extern void __might_sleep(const char *file, int line, int preempt_offset); extern void __cant_sleep(const char *file, int line, int preempt_offset); extern void __cant_migrate(const char *file, int line); @@ -168,8 +168,8 @@ extern void __cant_migrate(const char *file, int line); */ # define non_block_end() WARN_ON(current->non_block_count-- == 0) #else - static inline void ___might_sleep(const char *file, int line, - int preempt_offset) { } + static inline void __might_resched(const char *file, int line, + int preempt_offset) { } static inline void __might_sleep(const char *file, int line, int preempt_offset) { } # define might_sleep() do { might_resched(); } while (0) |