diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-03-07 21:00:34 +0100 |
|---|---|---|
| committer | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-02-13 00:36:20 +0100 |
| commit | cefc51199be89b977fd8e951df87d222d8bbc92a (patch) | |
| tree | 5a7d79a11a666f4573e1768137f733353fe29619 | |
| parent | 293e933a6e132d9224862cc85a99da0e8cec91ea (diff) | |
| download | rt-linux-cefc51199be89b977fd8e951df87d222d8bbc92a.tar.gz | |
fs: dcache: Use cpu_chill() in trylock loops
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@linutronix.de>
| -rw-r--r-- | fs/autofs4/autofs_i.h | 1 | ||||
| -rw-r--r-- | fs/autofs4/expire.c | 2 | ||||
| -rw-r--r-- | fs/dcache.c | 5 | ||||
| -rw-r--r-- | fs/namespace.c | 3 |
4 files changed, 7 insertions, 4 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index c37149b929be5..4c541347308e9 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -34,6 +34,7 @@ #include <linux/sched.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/delay.h> #include <asm/current.h> #include <asm/uaccess.h> diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index 1cebc3c52fa57..d487fa27add5b 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -150,7 +150,7 @@ again: parent = p->d_parent; if (!spin_trylock(&parent->d_lock)) { spin_unlock(&p->d_lock); - cpu_relax(); + cpu_chill(); goto relock; } spin_unlock(&p->d_lock); diff --git a/fs/dcache.c b/fs/dcache.c index 5c33aeb0f68fe..1b218d5932f0f 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -19,6 +19,7 @@ #include <linux/mm.h> #include <linux/fs.h> #include <linux/fsnotify.h> +#include <linux/delay.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/hash.h> @@ -589,7 +590,7 @@ static struct dentry *dentry_kill(struct dentry *dentry) failed: spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); return dentry; /* try again with same dentry */ } @@ -2398,7 +2399,7 @@ again: if (dentry->d_lockref.count == 1) { if (!spin_trylock(&inode->i_lock)) { spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); goto again; } dentry->d_flags &= ~DCACHE_CANT_MOUNT; diff --git a/fs/namespace.c b/fs/namespace.c index b52c0aea9e1a5..62588bfcddf4c 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -14,6 +14,7 @@ #include <linux/mnt_namespace.h> #include <linux/user_namespace.h> #include <linux/namei.h> +#include <linux/delay.h> #include <linux/security.h> #include <linux/idr.h> #include <linux/init.h> /* init_rootfs */ @@ -355,7 +356,7 @@ int __mnt_want_write(struct vfsmount *m) smp_mb(); while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) { preempt_enable(); - cpu_relax(); + cpu_chill(); preempt_disable(); } /* |