diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-03-07 21:00:34 +0100 |
|---|---|---|
| committer | Gary S. Robertson <gary.robertson@linaro.org> | 2014-05-07 08:56:10 -0500 |
| commit | 84bb9a4329c423b9e5b652251951c76dea733177 (patch) | |
| tree | 9b5f7c253ecb156c0e80dbf6174dfd0d7be3ff26 /fs | |
| parent | bb5518410611367d61611129b9259f41f1bfce58 (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
Diffstat (limited to 'fs')
| -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 | 7 |
4 files changed, 10 insertions, 7 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 3f1128b37e46..c2ed9c4f4cb1 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 13ddec92341c..b2f19030ca2c 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -157,7 +157,7 @@ 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 9a59653d3449..c65c38ee0e2b 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" @@ -453,7 +454,7 @@ 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)) @@ -835,7 +836,7 @@ relock: if (!spin_trylock(&dentry->d_lock)) { spin_unlock(&dcache_lru_lock); - cpu_relax(); + cpu_chill(); goto relock; } @@ -2072,7 +2073,7 @@ again: if (dentry->d_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 1939f6ab3a96..7a4f8d878f3b 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -23,6 +23,7 @@ #include <linux/uaccess.h> #include <linux/proc_ns.h> #include <linux/magic.h> +#include <linux/delay.h> #include "pnode.h" #include "internal.h" @@ -317,7 +318,7 @@ 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(); } /* @@ -1289,7 +1290,7 @@ static int do_umount(struct mount *mnt, int flags) return retval; } -/* +/* * Is the caller allowed to modify his namespace? */ static inline bool may_mount(void) @@ -1717,7 +1718,7 @@ static int do_loopback(struct path *path, const char *old_name, err = -EINVAL; if (mnt_ns_loop(&old_path)) - goto out; + goto out; mp = lock_mount(path); err = PTR_ERR(mp); |