[tip: locking/core] sched: Make cond_resched_*lock() variants consistent vs. might_sleep()

From: tip-bot2 for Thomas Gleixner
Date: Fri Oct 01 2021 - 11:05:46 EST


The following commit has been merged into the locking/core branch of tip:

Commit-ID: 7b5ff4bb9adc53cfbf7ac9ba7820ccf0cd7c070a
Gitweb: https://git.kernel.org/tip/7b5ff4bb9adc53cfbf7ac9ba7820ccf0cd7c070a
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Thu, 23 Sep 2021 18:54:37 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Fri, 01 Oct 2021 13:57:50 +02:00

sched: Make cond_resched_*lock() variants consistent vs. might_sleep()

Commit 3427445afd26 ("sched: Exclude cond_resched() from nested sleep
test") removed the task state check of __might_sleep() for
cond_resched_lock() because cond_resched_lock() is not a voluntary
scheduling point which blocks. It's a preemption point which requires the
lock holder to release the spin lock.

The same rationale applies to cond_resched_rwlock_read/write(), but those
were not touched.

Make it consistent and use the non-state checking __might_resched() there
as well.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20210923165357.991262778@xxxxxxxxxxxxx
---
include/linux/sched.h | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index b38f002..7a989f2 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2051,14 +2051,14 @@ extern int __cond_resched_rwlock_write(rwlock_t *lock);
__cond_resched_lock(lock); \
})

-#define cond_resched_rwlock_read(lock) ({ \
- __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
- __cond_resched_rwlock_read(lock); \
+#define cond_resched_rwlock_read(lock) ({ \
+ __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
+ __cond_resched_rwlock_read(lock); \
})

-#define cond_resched_rwlock_write(lock) ({ \
- __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
- __cond_resched_rwlock_write(lock); \
+#define cond_resched_rwlock_write(lock) ({ \
+ __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
+ __cond_resched_rwlock_write(lock); \
})

static inline void cond_resched_rcu(void)