[PATCH RT 5/7] fs: namespace: Use cpu_chill() instead of cpu_relax()
From: Steven Rostedt
Date: Tue Mar 13 2012 - 22:31:46 EST
From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Retry loops on RT might loop forever when the modifying side was
preempted. Use cpu_chill() instead of cpu_relax() to let the system
make progress.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: stable-rt@xxxxxxxxxxxxxxx
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
fs/namespace.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index c563781..3270cde 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -31,6 +31,7 @@
#include <linux/idr.h>
#include <linux/fs_struct.h>
#include <linux/fsnotify.h>
+#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include "pnode.h"
@@ -346,7 +347,7 @@ int mnt_want_write(struct vfsmount *mnt)
*/
while (mnt->mnt_flags & MNT_WRITE_HOLD) {
preempt_enable();
- cpu_relax();
+ cpu_chill();
preempt_disable();
}
/*
--
1.7.8.3
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