diff mbox series

[RT,08/10] locking: Drop might_resched() from might_sleep_no_state_check()

Message ID 20211122203904.807323639@goodmis.org
State Superseded
Headers show
Series Linux 5.10.78-rt56-rc2 | expand

Commit Message

Steven Rostedt Nov. 22, 2021, 8:38 p.m. UTC 
5.10.78-rt56-rc2 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

might_sleep_no_state_check() serves the same purpose as might_sleep()
except it is used before sleeping locks are acquired and therefore does
not check task_struct::state because the state is preserved.

That state is preserved in the locking slow path so we must not schedule
at the begin of the locking function because the state will be lost and
not preserved at that time.

Remove might_resched() from might_sleep_no_state_check() to avoid losing the
state before it is preserved.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 include/linux/kernel.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2cff7554395d..6eb0ab994f4c 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -222,7 +222,7 @@  extern void __cant_migrate(const char *file, int line);
 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
 
 # define might_sleep_no_state_check() \
-	do { ___might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+	do { ___might_sleep(__FILE__, __LINE__, 0); } while (0)
 
 /**
  * cant_sleep - annotation for functions that cannot sleep