diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-03-07 21:00:34 +0100 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2012-04-10 16:41:07 -0500 |
| commit | 20decb543187374cda4666de96e1bd390b5d5a07 (patch) | |
| tree | 67042681e588258e99bc528fad543b1ee2e3c6a5 | |
| parent | f16e2a70d6b09add4156f9ec850597efd00b21fd (diff) | |
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>
Cc: stable-rt@vger.kernel.org
| -rw-r--r-- | fs/autofs4/autofs_i.h | 1 | ||||
| -rw-r--r-- | fs/autofs4/expire.c | 2 | ||||
| -rw-r--r-- | fs/dcache.c | 7 | ||||
| -rw-r--r-- | fs/namespace.c | 3 |
4 files changed, 8 insertions, 5 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index eb1cc92cd67d..c5a1ce74ff6b 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 1feb68ecef95..859badd23da6 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -171,7 +171,7 @@ 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 b60ddc41d783..04d701684fb7 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -37,6 +37,7 @@ #include <linux/rculist_bl.h> #include <linux/prefetch.h> #include <linux/ratelimit.h> +#include <linux/delay.h> #include "internal.h" #include "mount.h" @@ -454,7 +455,7 @@ static inline struct dentry *dentry_kill(struct dentry *dentry, int ref) if (inode && !spin_trylock(&inode->i_lock)) { relock: spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); return dentry; /* try again with same dentry */ } if (IS_ROOT(dentry)) @@ -840,7 +841,7 @@ relock: if (!spin_trylock(&dentry->d_lock)) { spin_unlock(&dcache_lru_lock); - cpu_relax(); + cpu_chill(); goto relock; } @@ -2022,7 +2023,7 @@ again: if (dentry->d_count == 1) { if (inode && !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 7fd098124790..4d20e76c0be6 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -20,6 +20,7 @@ #include <linux/fs_struct.h> /* get_fs_root et.al. */ #include <linux/fsnotify.h> /* fsnotify_vfsmount_delete */ #include <linux/uaccess.h> +#include <linux/delay.h> #include "pnode.h" #include "internal.h" @@ -315,7 +316,7 @@ int mnt_want_write(struct vfsmount *m) smp_mb(); while (mnt->mnt.mnt_flags & MNT_WRITE_HOLD) { preempt_enable(); - cpu_relax(); + cpu_chill(); preempt_disable(); } /* |