[PATCH RT 7/9] rt/locking: allow recursive local_trylock()
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2017-12-02 01:37:26
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
4.4.102-rt117-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> required for following networking patch which does recursive try-lock. While at it, add the !RT version of it because it did not yet exist. Cc: stable-rt@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- include/linux/locallock.h | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/include/linux/locallock.h b/include/linux/locallock.h
index e572a3971631..0baaf28dc4ee 100644
--- a/include/linux/locallock.h
+++ b/include/linux/locallock.h@@ -77,6 +77,9 @@ static inline int __local_trylock(struct local_irq_lock *lv) lv->owner = current; lv->nestcnt = 1; return 1; + } else if (lv->owner == current) { + lv->nestcnt++; + return 1; } return 0; }
@@ -250,6 +253,12 @@ static inline int __local_unlock_irqrestore(struct local_irq_lock *lv, static inline void local_irq_lock_init(int lvar) { } +#define local_trylock(lvar) \ + ({ \ + preempt_disable(); \ + 1; \ + }) + #define local_lock(lvar) preempt_disable() #define local_unlock(lvar) preempt_enable() #define local_lock_irq(lvar) local_irq_disable()
--
2.13.2