Jetpack/kernel/kernel-4.9/rt-patches/0344-rt-locking-allow-recur...

45 lines
1.3 KiB
Diff

From 9074571ec0afa51c73bfd9910906961b48c17f31 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Thu, 21 Sep 2017 14:39:56 +0200
Subject: [PATCH 344/352] rt/locking: allow recursive local_trylock()
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 845c77f..280f884 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()
--
2.7.4