From: npiggin@suse.de
To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [patch 10/27] fs: dcache scale dentry refcount
Date: Sat, 25 Apr 2009 11:20:30 +1000 [thread overview]
Message-ID: <20090425012210.450828592@suse.de> (raw)
In-Reply-To: 20090425012020.457460929@suse.de
[-- Attachment #1: fs-dcache-scale-d_count.patch --]
[-- Type: text/plain, Size: 25048 bytes --]
Make d_count non-atomic and protect it with d_lock. This allows us to
ensure a 0 refcount dentry remains 0 without dcache_lock. It is also
fairly natural when we start protecting many other dentry members with
d_lock.
---
arch/powerpc/platforms/cell/spufs/inode.c | 2
drivers/infiniband/hw/ipath/ipath_fs.c | 2
fs/autofs4/expire.c | 8 +-
fs/autofs4/root.c | 6 -
fs/coda/dir.c | 2
fs/configfs/dir.c | 3
fs/configfs/inode.c | 2
fs/dcache.c | 103 ++++++++++++++++++++++--------
fs/ecryptfs/inode.c | 2
fs/exportfs/expfs.c | 8 ++
fs/hpfs/namei.c | 2
fs/locks.c | 2
fs/namei.c | 2
fs/nfs/dir.c | 12 +--
fs/nfsd/vfs.c | 5 -
fs/notify/dnotify/dnotify.c | 11 ++-
fs/notify/inotify/inotify.c | 12 ++-
fs/smbfs/dir.c | 8 ++
fs/smbfs/proc.c | 8 ++
include/linux/dcache.h | 29 ++++----
kernel/cgroup.c | 2
net/sunrpc/rpc_pipe.c | 2
22 files changed, 157 insertions(+), 76 deletions(-)
Index: linux-2.6/fs/dcache.c
===================================================================
--- linux-2.6.orig/fs/dcache.c
+++ linux-2.6/fs/dcache.c
@@ -107,6 +107,7 @@ static void d_callback(struct rcu_head *
static void d_free(struct dentry *dentry)
{
atomic_dec(&dentry_stat.nr_dentry);
+ BUG_ON(dentry->d_count);
if (dentry->d_op && dentry->d_op->d_release)
dentry->d_op->d_release(dentry);
/* if dentry was never inserted into hash, immediate free is OK */
@@ -258,13 +259,23 @@ void dput(struct dentry *dentry)
return;
repeat:
- if (atomic_read(&dentry->d_count) == 1)
+ if (dentry->d_count == 1)
might_sleep();
- if (!atomic_dec_and_lock(&dentry->d_count, &dcache_lock))
- return;
-
spin_lock(&dentry->d_lock);
- if (atomic_read(&dentry->d_count)) {
+ if (dentry->d_count == 1) {
+ if (!spin_trylock(&dcache_lock)) {
+ /*
+ * Something of a livelock possibility we could avoid
+ * by taking dcache_lock and trying again, but we
+ * want to reduce dcache_lock anyway so this will
+ * get improved.
+ */
+ spin_unlock(&dentry->d_lock);
+ goto repeat;
+ }
+ }
+ dentry->d_count--;
+ if (dentry->d_count) {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
return;
@@ -341,7 +352,7 @@ int d_invalidate(struct dentry * dentry)
* working directory or similar).
*/
spin_lock(&dentry->d_lock);
- if (atomic_read(&dentry->d_count) > 1) {
+ if (dentry->d_count > 1) {
if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)) {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
@@ -355,28 +366,54 @@ int d_invalidate(struct dentry * dentry)
return 0;
}
-/* This should be called _only_ with dcache_lock held */
+/* This should be called _only_ with a lock pinning the dentry */
static inline struct dentry * __dget_locked_dlock(struct dentry *dentry)
{
- atomic_inc(&dentry->d_count);
+ dentry->d_count++;
dentry_lru_del_init(dentry);
return dentry;
}
static inline struct dentry * __dget_locked(struct dentry *dentry)
{
- atomic_inc(&dentry->d_count);
spin_lock(&dentry->d_lock);
- dentry_lru_del_init(dentry);
+ __dget_locked_dlock(dentry);
spin_lock(&dentry->d_lock);
return dentry;
}
+struct dentry * dget_locked_dlock(struct dentry *dentry)
+{
+ return __dget_locked_dlock(dentry);
+}
+
struct dentry * dget_locked(struct dentry *dentry)
{
return __dget_locked(dentry);
}
+struct dentry *dget_parent(struct dentry *dentry)
+{
+ struct dentry *ret;
+
+repeat:
+ spin_lock(&dentry->d_lock);
+ ret = dentry->d_parent;
+ if (!ret)
+ goto out;
+ if (!spin_trylock(&ret->d_lock)) {
+ spin_unlock(&dentry->d_lock);
+ goto repeat;
+ }
+ BUG_ON(!ret->d_count);
+ ret->d_count++;
+ spin_unlock(&ret->d_lock);
+out:
+ spin_unlock(&dentry->d_lock);
+ return ret;
+}
+EXPORT_SYMBOL(dget_parent);
+
/**
* d_find_alias - grab a hashed alias of inode
* @inode: inode in question
@@ -444,7 +481,7 @@ restart:
spin_lock(&dcache_lock);
list_for_each_entry(dentry, &inode->i_dentry, d_alias) {
spin_lock(&dentry->d_lock);
- if (!atomic_read(&dentry->d_count)) {
+ if (!dentry->d_count) {
__dget_locked_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
@@ -479,7 +516,10 @@ static void prune_one_dentry(struct dent
*/
while (dentry) {
spin_lock(&dcache_lock);
- if (!atomic_dec_and_lock(&dentry->d_count, &dentry->d_lock)) {
+ spin_lock(&dentry->d_lock);
+ dentry->d_count--;
+ if (dentry->d_count) {
+ spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
return;
}
@@ -565,7 +605,7 @@ again:
* the LRU because of laziness during lookup. Do not free
* it - just keep it off the LRU list.
*/
- if (atomic_read(&dentry->d_count)) {
+ if (dentry->d_count) {
spin_unlock(&dentry->d_lock);
continue;
}
@@ -726,7 +766,7 @@ static void shrink_dcache_for_umount_sub
do {
struct inode *inode;
- if (atomic_read(&dentry->d_count) != 0) {
+ if (dentry->d_count != 0) {
printk(KERN_ERR
"BUG: Dentry %p{i=%lx,n=%s}"
" still in use (%d)"
@@ -735,7 +775,7 @@ static void shrink_dcache_for_umount_sub
dentry->d_inode ?
dentry->d_inode->i_ino : 0UL,
dentry->d_name.name,
- atomic_read(&dentry->d_count),
+ dentry->d_count,
dentry->d_sb->s_type->name,
dentry->d_sb->s_id);
BUG();
@@ -745,7 +785,9 @@ static void shrink_dcache_for_umount_sub
parent = NULL;
else {
parent = dentry->d_parent;
- atomic_dec(&parent->d_count);
+ spin_lock(&parent->d_lock);
+ parent->d_count--;
+ spin_unlock(&parent->d_lock);
}
list_del(&dentry->d_u.d_child);
@@ -800,7 +842,9 @@ void shrink_dcache_for_umount(struct sup
dentry = sb->s_root;
sb->s_root = NULL;
- atomic_dec(&dentry->d_count);
+ spin_lock(&dentry->d_lock);
+ dentry->d_count--;
+ spin_unlock(&dentry->d_lock);
shrink_dcache_for_umount_subtree(dentry);
while (!hlist_empty(&sb->s_anon)) {
@@ -892,17 +936,15 @@ resume:
spin_lock(&dentry->d_lock);
dentry_lru_del_init(dentry);
- spin_unlock(&dentry->d_lock);
/*
* move only zero ref count dentries to the end
* of the unused list for prune_dcache
*/
- if (!atomic_read(&dentry->d_count)) {
- spin_lock(&dentry->d_lock);
+ if (!dentry->d_count) {
dentry_lru_add_tail(dentry);
- spin_unlock(&dentry->d_lock);
found++;
}
+ spin_unlock(&dentry->d_lock);
/*
* We can return to the caller if we have found some (this
@@ -1011,7 +1053,7 @@ struct dentry *d_alloc(struct dentry * p
memcpy(dname, name->name, name->len);
dname[name->len] = 0;
- atomic_set(&dentry->d_count, 1);
+ dentry->d_count = 1;
dentry->d_flags = DCACHE_UNHASHED;
spin_lock_init(&dentry->d_lock);
dentry->d_inode = NULL;
@@ -1479,7 +1521,7 @@ struct dentry * __d_lookup(struct dentry
goto next;
}
- atomic_inc(&dentry->d_count);
+ dentry->d_count++;
found = dentry;
spin_unlock(&dentry->d_lock);
break;
@@ -1540,6 +1582,7 @@ int d_validate(struct dentry *dentry, st
goto out;
spin_lock(&dcache_lock);
+ spin_lock(&dentry->d_lock);
spin_lock(&dcache_hash_lock);
base = d_hash(dparent, dentry->d_name.hash);
hlist_for_each(lhp,base) {
@@ -1548,12 +1591,14 @@ int d_validate(struct dentry *dentry, st
*/
if (dentry == hlist_entry(lhp, struct dentry, d_hash)) {
spin_unlock(&dcache_hash_lock);
- __dget_locked(dentry);
+ __dget_locked_dlock(dentry);
+ spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
return 1;
}
}
spin_unlock(&dcache_hash_lock);
+ spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
out:
return 0;
@@ -1589,7 +1634,7 @@ void d_delete(struct dentry * dentry)
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
isdir = S_ISDIR(dentry->d_inode->i_mode);
- if (atomic_read(&dentry->d_count) == 1) {
+ if (dentry->d_count == 1) {
dentry_iput(dentry);
fsnotify_nameremove(dentry, isdir);
return;
@@ -2265,11 +2310,15 @@ resume:
this_parent = dentry;
goto repeat;
}
- atomic_dec(&dentry->d_count);
+ spin_lock(&dentry->d_lock);
+ dentry->d_count--;
+ spin_unlock(&dentry->d_lock);
}
if (this_parent != root) {
next = this_parent->d_u.d_child.next;
- atomic_dec(&this_parent->d_count);
+ spin_lock(&this_parent->d_lock);
+ this_parent->d_count--;
+ spin_unlock(&this_parent->d_lock);
this_parent = this_parent->d_parent;
goto resume;
}
Index: linux-2.6/include/linux/dcache.h
===================================================================
--- linux-2.6.orig/include/linux/dcache.h
+++ linux-2.6/include/linux/dcache.h
@@ -87,7 +87,7 @@ full_name_hash(const unsigned char *name
#endif
struct dentry {
- atomic_t d_count;
+ unsigned int d_count; /* protected by d_lock */
unsigned int d_flags; /* protected by d_lock */
spinlock_t d_lock; /* per dentry lock */
int d_mounted;
@@ -330,17 +330,28 @@ extern char *dentry_path(struct dentry *
* needs and they take necessary precautions) you should hold dcache_lock
* and call dget_locked() instead of dget().
*/
-
+static inline struct dentry *dget_dlock(struct dentry *dentry)
+{
+ if (dentry) {
+ BUG_ON(!dentry->d_count);
+ dentry->d_count++;
+ }
+ return dentry;
+}
static inline struct dentry *dget(struct dentry *dentry)
{
if (dentry) {
- BUG_ON(!atomic_read(&dentry->d_count));
- atomic_inc(&dentry->d_count);
+ spin_lock(&dentry->d_lock);
+ dget_dlock(dentry);
+ spin_unlock(&dentry->d_lock);
}
return dentry;
}
extern struct dentry * dget_locked(struct dentry *);
+extern struct dentry * dget_locked_dlock(struct dentry *);
+
+extern struct dentry *dget_parent(struct dentry *dentry);
/**
* d_unhashed - is dentry hashed
@@ -354,16 +365,6 @@ static inline int d_unhashed(struct dent
return (dentry->d_flags & DCACHE_UNHASHED);
}
-static inline struct dentry *dget_parent(struct dentry *dentry)
-{
- struct dentry *ret;
-
- spin_lock(&dentry->d_lock);
- ret = dget(dentry->d_parent);
- spin_unlock(&dentry->d_lock);
- return ret;
-}
-
extern void dput(struct dentry *);
static inline int d_mountpoint(struct dentry *dentry)
Index: linux-2.6/fs/configfs/dir.c
===================================================================
--- linux-2.6.orig/fs/configfs/dir.c
+++ linux-2.6/fs/configfs/dir.c
@@ -311,8 +311,7 @@ static void remove_dir(struct dentry * d
if (d->d_inode)
simple_rmdir(parent->d_inode,d);
- pr_debug(" o %s removing done (%d)\n",d->d_name.name,
- atomic_read(&d->d_count));
+ pr_debug(" o %s removing done (%d)\n",d->d_name.name, d->d_count);
dput(parent);
}
Index: linux-2.6/fs/locks.c
===================================================================
--- linux-2.6.orig/fs/locks.c
+++ linux-2.6/fs/locks.c
@@ -1373,7 +1373,7 @@ int generic_setlease(struct file *filp,
if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
goto out;
if ((arg == F_WRLCK)
- && ((atomic_read(&dentry->d_count) > 1)
+ && (dentry->d_count > 1
|| (atomic_read(&inode->i_count) > 1)))
goto out;
}
Index: linux-2.6/fs/namei.c
===================================================================
--- linux-2.6.orig/fs/namei.c
+++ linux-2.6/fs/namei.c
@@ -2116,7 +2116,7 @@ void dentry_unhash(struct dentry *dentry
shrink_dcache_parent(dentry);
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
- if (atomic_read(&dentry->d_count) == 2)
+ if (dentry->d_count == 2)
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
Index: linux-2.6/fs/autofs4/expire.c
===================================================================
--- linux-2.6.orig/fs/autofs4/expire.c
+++ linux-2.6/fs/autofs4/expire.c
@@ -197,7 +197,7 @@ static int autofs4_tree_busy(struct vfsm
else
ino_count++;
- if (atomic_read(&p->d_count) > ino_count) {
+ if (p->d_count > ino_count) {
top_ino->last_used = jiffies;
dput(p);
return 1;
@@ -346,7 +346,7 @@ struct dentry *autofs4_expire_indirect(s
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 2;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
/* Can we umount this guy */
@@ -368,7 +368,7 @@ struct dentry *autofs4_expire_indirect(s
if (!exp_leaves) {
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 1;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
@@ -382,7 +382,7 @@ struct dentry *autofs4_expire_indirect(s
} else {
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 1;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
Index: linux-2.6/fs/autofs4/root.c
===================================================================
--- linux-2.6.orig/fs/autofs4/root.c
+++ linux-2.6/fs/autofs4/root.c
@@ -381,7 +381,7 @@ static struct dentry *autofs4_lookup_act
spin_lock(&dentry->d_lock);
/* Already gone? */
- if (atomic_read(&dentry->d_count) == 0)
+ if (dentry->d_count == 0)
goto next;
qstr = &dentry->d_name;
@@ -397,7 +397,7 @@ static struct dentry *autofs4_lookup_act
goto next;
if (d_unhashed(dentry)) {
- dget(dentry);
+ dget_locked_dlock(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&sbi->lookup_lock);
spin_unlock(&dcache_lock);
@@ -449,7 +449,7 @@ static struct dentry *autofs4_lookup_exp
goto next;
if (d_unhashed(dentry)) {
- dget(dentry);
+ dget_locked_dlock(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&sbi->lookup_lock);
spin_unlock(&dcache_lock);
Index: linux-2.6/fs/coda/dir.c
===================================================================
--- linux-2.6.orig/fs/coda/dir.c
+++ linux-2.6/fs/coda/dir.c
@@ -611,7 +611,7 @@ static int coda_dentry_revalidate(struct
if (cii->c_flags & C_FLUSH)
coda_flag_inode_children(inode, C_FLUSH);
- if (atomic_read(&de->d_count) > 1)
+ if (de->d_count > 1)
/* pretend it's valid, but don't change the flags */
goto out;
Index: linux-2.6/fs/ecryptfs/inode.c
===================================================================
--- linux-2.6.orig/fs/ecryptfs/inode.c
+++ linux-2.6/fs/ecryptfs/inode.c
@@ -263,7 +263,7 @@ int ecryptfs_lookup_and_interpose_lower(
ecryptfs_dentry->d_parent));
lower_inode = lower_dentry->d_inode;
fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
- BUG_ON(!atomic_read(&lower_dentry->d_count));
+ BUG_ON(!lower_dentry->d_count);
ecryptfs_set_dentry_private(ecryptfs_dentry,
kmem_cache_alloc(ecryptfs_dentry_info_cache,
GFP_KERNEL));
Index: linux-2.6/fs/hpfs/namei.c
===================================================================
--- linux-2.6.orig/fs/hpfs/namei.c
+++ linux-2.6/fs/hpfs/namei.c
@@ -414,7 +414,7 @@ again:
mutex_unlock(&hpfs_i(inode)->i_parent_mutex);
d_drop(dentry);
spin_lock(&dentry->d_lock);
- if (atomic_read(&dentry->d_count) > 1 ||
+ if (dentry->d_count > 1 ||
generic_permission(inode, MAY_WRITE, NULL) ||
!S_ISREG(inode->i_mode) ||
get_write_access(inode)) {
Index: linux-2.6/fs/nfs/dir.c
===================================================================
--- linux-2.6.orig/fs/nfs/dir.c
+++ linux-2.6/fs/nfs/dir.c
@@ -1326,7 +1326,7 @@ static int nfs_sillyrename(struct inode
dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
dentry->d_parent->d_name.name, dentry->d_name.name,
- atomic_read(&dentry->d_count));
+ dentry->d_count);
nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
/*
@@ -1435,7 +1435,7 @@ static int nfs_unlink(struct inode *dir,
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
- if (atomic_read(&dentry->d_count) > 1) {
+ if (dentry->d_count > 1) {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
/* Start asynchronous writeout of the inode */
@@ -1590,7 +1590,7 @@ static int nfs_rename(struct inode *old_
dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
- atomic_read(&new_dentry->d_count));
+ new_dentry->d_count);
/*
* First check whether the target is busy ... we can't
@@ -1606,7 +1606,7 @@ static int nfs_rename(struct inode *old_
error = -EISDIR;
if (!S_ISDIR(old_inode->i_mode))
goto out;
- } else if (atomic_read(&new_dentry->d_count) > 2) {
+ } else if (new_dentry->d_count > 2) {
int err;
/* copy the target dentry's name */
dentry = d_alloc(new_dentry->d_parent,
@@ -1621,7 +1621,7 @@ static int nfs_rename(struct inode *old_
new_inode = NULL;
/* instantiate the replacement target */
d_instantiate(new_dentry, NULL);
- } else if (atomic_read(&new_dentry->d_count) > 1)
+ } else if (new_dentry->d_count > 1)
/* dentry still busy? */
goto out;
}
@@ -1630,7 +1630,7 @@ go_ahead:
/*
* ... prune child dentries and writebacks if needed.
*/
- if (atomic_read(&old_dentry->d_count) > 1) {
+ if (old_dentry->d_count > 1) {
if (S_ISREG(old_inode->i_mode))
nfs_wb_all(old_inode);
shrink_dcache_parent(old_dentry);
Index: linux-2.6/fs/nfsd/vfs.c
===================================================================
--- linux-2.6.orig/fs/nfsd/vfs.c
+++ linux-2.6/fs/nfsd/vfs.c
@@ -1735,8 +1735,7 @@ nfsd_rename(struct svc_rqst *rqstp, stru
goto out_dput_new;
if (svc_msnfs(ffhp) &&
- ((atomic_read(&odentry->d_count) > 1)
- || (atomic_read(&ndentry->d_count) > 1))) {
+ ((odentry->d_count > 1) || (ndentry->d_count > 1))) {
host_err = -EPERM;
goto out_dput_new;
}
@@ -1822,7 +1821,7 @@ nfsd_unlink(struct svc_rqst *rqstp, stru
if (type != S_IFDIR) { /* It's UNLINK */
#ifdef MSNFS
if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
- (atomic_read(&rdentry->d_count) > 1)) {
+ (rdentry->d_count > 1)) {
host_err = -EPERM;
} else
#endif
Index: linux-2.6/fs/exportfs/expfs.c
===================================================================
--- linux-2.6.orig/fs/exportfs/expfs.c
+++ linux-2.6/fs/exportfs/expfs.c
@@ -74,11 +74,17 @@ static struct dentry *
find_disconnected_root(struct dentry *dentry)
{
dget(dentry);
+again:
spin_lock(&dentry->d_lock);
while (!IS_ROOT(dentry) &&
(dentry->d_parent->d_flags & DCACHE_DISCONNECTED)) {
struct dentry *parent = dentry->d_parent;
- dget(parent);
+
+ if (!spin_trylock(&parent->d_lock)) {
+ spin_unlock(&dentry->d_lock);
+ goto again;
+ }
+ dget_dlock(parent);
spin_unlock(&dentry->d_lock);
dput(dentry);
dentry = parent;
Index: linux-2.6/fs/notify/dnotify/dnotify.c
===================================================================
--- linux-2.6.orig/fs/notify/dnotify/dnotify.c
+++ linux-2.6/fs/notify/dnotify/dnotify.c
@@ -168,15 +168,24 @@ void dnotify_parent(struct dentry *dentr
if (!dir_notify_enable)
return;
+again:
spin_lock(&dentry->d_lock);
parent = dentry->d_parent;
+ if (parent != dentry && !spin_trylock(&parent->d_lock)) {
+ spin_unlock(&dentry->d_lock);
+ goto again;
+ }
if (parent->d_inode->i_dnotify_mask & event) {
- dget(parent);
+ dget_dlock(parent);
spin_unlock(&dentry->d_lock);
+ if (parent != dentry)
+ spin_unlock(&parent->d_lock);
__inode_dir_notify(parent->d_inode, event);
dput(parent);
} else {
spin_unlock(&dentry->d_lock);
+ if (parent != dentry)
+ spin_unlock(&parent->d_lock);
}
}
EXPORT_SYMBOL_GPL(dnotify_parent);
Index: linux-2.6/fs/notify/inotify/inotify.c
===================================================================
--- linux-2.6.orig/fs/notify/inotify/inotify.c
+++ linux-2.6/fs/notify/inotify/inotify.c
@@ -338,18 +338,26 @@ void inotify_dentry_parent_queue_event(s
if (!(dentry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED))
return;
+again:
spin_lock(&dentry->d_lock);
parent = dentry->d_parent;
+ if (!spin_trylock(&parent->d_lock)) {
+ spin_unlock(&dentry->d_lock);
+ goto again;
+ }
inode = parent->d_inode;
if (inotify_inode_watched(inode)) {
- dget(parent);
+ dget_dlock(parent);
spin_unlock(&dentry->d_lock);
+ spin_unlock(&parent->d_lock);
inotify_inode_queue_event(inode, mask, cookie, name,
dentry->d_inode);
dput(parent);
- } else
+ } else {
spin_unlock(&dentry->d_lock);
+ spin_unlock(&parent->d_lock);
+ }
}
EXPORT_SYMBOL_GPL(inotify_dentry_parent_queue_event);
Index: linux-2.6/fs/smbfs/dir.c
===================================================================
--- linux-2.6.orig/fs/smbfs/dir.c
+++ linux-2.6/fs/smbfs/dir.c
@@ -405,6 +405,7 @@ void
smb_renew_times(struct dentry * dentry)
{
dget(dentry);
+again:
spin_lock(&dentry->d_lock);
for (;;) {
struct dentry *parent;
@@ -413,8 +414,13 @@ smb_renew_times(struct dentry * dentry)
if (IS_ROOT(dentry))
break;
parent = dentry->d_parent;
- dget(parent);
+ if (!spin_trylock(&parent->d_lock)) {
+ spin_unlock(&dentry->d_lock);
+ goto again;
+ }
+ dget_dlock(parent);
spin_unlock(&dentry->d_lock);
+ spin_unlock(&parent->d_lock);
dput(dentry);
dentry = parent;
spin_lock(&dentry->d_lock);
Index: linux-2.6/fs/smbfs/proc.c
===================================================================
--- linux-2.6.orig/fs/smbfs/proc.c
+++ linux-2.6/fs/smbfs/proc.c
@@ -332,6 +332,7 @@ static int smb_build_path(struct smb_sb_
* and store it in reversed order [see reverse_string()]
*/
dget(entry);
+again:
spin_lock(&entry->d_lock);
while (!IS_ROOT(entry)) {
struct dentry *parent;
@@ -350,6 +351,7 @@ static int smb_build_path(struct smb_sb_
dput(entry);
return len;
}
+
reverse_string(path, len);
path += len;
if (unicode) {
@@ -361,7 +363,11 @@ static int smb_build_path(struct smb_sb_
maxlen -= len+1;
parent = entry->d_parent;
- dget(parent);
+ if (!spin_trylock(&parent->d_lock)) {
+ spin_unlock(&entry->d_lock);
+ goto again;
+ }
+ dget_dlock(parent);
spin_unlock(&entry->d_lock);
dput(entry);
entry = parent;
Index: linux-2.6/kernel/cgroup.c
===================================================================
--- linux-2.6.orig/kernel/cgroup.c
+++ linux-2.6/kernel/cgroup.c
@@ -2728,9 +2728,7 @@ again:
list_del(&cgrp->sibling);
cgroup_unlock_hierarchy(cgrp->root);
- spin_lock(&cgrp->dentry->d_lock);
d = dget(cgrp->dentry);
- spin_unlock(&d->d_lock);
cgroup_d_remove_dir(d);
dput(d);
Index: linux-2.6/arch/powerpc/platforms/cell/spufs/inode.c
===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/spufs/inode.c
+++ linux-2.6/arch/powerpc/platforms/cell/spufs/inode.c
@@ -161,7 +161,7 @@ static void spufs_prune_dir(struct dentr
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!(d_unhashed(dentry)) && dentry->d_inode) {
- dget_locked(dentry);
+ dget_locked_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
simple_unlink(dir->d_inode, dentry);
Index: linux-2.6/drivers/infiniband/hw/ipath/ipath_fs.c
===================================================================
--- linux-2.6.orig/drivers/infiniband/hw/ipath/ipath_fs.c
+++ linux-2.6/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -275,7 +275,7 @@ static int remove_file(struct dentry *pa
spin_lock(&dcache_lock);
spin_lock(&tmp->d_lock);
if (!(d_unhashed(tmp) && tmp->d_inode)) {
- dget_locked(tmp);
+ dget_locked_dlock(tmp);
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
spin_unlock(&dcache_lock);
Index: linux-2.6/fs/configfs/inode.c
===================================================================
--- linux-2.6.orig/fs/configfs/inode.c
+++ linux-2.6/fs/configfs/inode.c
@@ -218,7 +218,7 @@ void configfs_drop_dentry(struct configf
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!(d_unhashed(dentry) && dentry->d_inode)) {
- dget_locked(dentry);
+ dget_locked_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
Index: linux-2.6/net/sunrpc/rpc_pipe.c
===================================================================
--- linux-2.6.orig/net/sunrpc/rpc_pipe.c
+++ linux-2.6/net/sunrpc/rpc_pipe.c
@@ -556,7 +556,7 @@ repeat:
continue;
spin_lock(&dentry->d_lock);
if (!d_unhashed(dentry)) {
- dget_locked(dentry);
+ dget_locked_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
dvec[n++] = dentry;
next prev parent reply other threads:[~2009-04-25 1:39 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-25 1:20 [patch 00/27] [rfc] vfs scalability patchset npiggin
2009-04-25 1:20 ` [patch 01/27] fs: cleanup files_lock npiggin
2009-04-25 3:20 ` Al Viro
2009-04-25 5:35 ` Eric W. Biederman
2009-04-26 6:12 ` Nick Piggin
2009-04-25 9:42 ` Alan Cox
2009-04-26 6:15 ` Nick Piggin
2009-04-25 1:20 ` [patch 02/27] fs: scale files_lock npiggin
2009-04-25 3:32 ` Al Viro
2009-04-25 1:20 ` [patch 03/27] fs: mnt_want_write speedup npiggin
2009-04-25 1:20 ` [patch 04/27] fs: introduce mnt_clone_write npiggin
2009-04-25 3:35 ` Al Viro
2009-04-25 1:20 ` [patch 05/27] fs: brlock vfsmount_lock npiggin
2009-04-25 3:50 ` Al Viro
2009-04-26 6:36 ` Nick Piggin
2009-04-25 1:20 ` [patch 06/27] fs: dcache fix LRU ordering npiggin
2009-04-25 1:20 ` [patch 07/27] fs: dcache scale hash npiggin
2009-04-25 1:20 ` [patch 08/27] fs: dcache scale lru npiggin
2009-04-25 1:20 ` [patch 09/27] fs: dcache scale nr_dentry npiggin
2009-04-25 1:20 ` npiggin [this message]
2009-04-25 1:20 ` [patch 11/27] fs: dcache scale d_unhashed npiggin
2009-04-25 1:20 ` [patch 12/27] fs: dcache scale subdirs npiggin
2009-04-25 1:20 ` [patch 13/27] fs: scale inode alias list npiggin
2009-04-25 1:20 ` [patch 14/27] fs: use RCU / seqlock logic for reverse and multi-step operaitons npiggin
2009-04-25 1:20 ` [patch 15/27] fs: dcache remove dcache_lock npiggin
2009-04-25 1:20 ` [patch 16/27] fs: dcache reduce dput locking npiggin
2009-04-25 1:20 ` [patch 17/27] fs: dcache per-bucket dcache hash locking npiggin
2009-04-25 1:20 ` [patch 18/27] fs: dcache reduce dcache_inode_lock npiggin
2009-04-25 1:20 ` [patch 19/27] fs: dcache per-inode inode alias locking npiggin
2009-04-25 1:20 ` [patch 20/27] fs: icache lock s_inodes list npiggin
2009-04-25 1:20 ` [patch 21/27] fs: icache lock inode hash npiggin
2009-04-25 1:20 ` [patch 22/27] fs: icache lock i_state npiggin
2009-04-25 1:20 ` [patch 23/27] fs: icache lock i_count npiggin
2009-04-25 1:20 ` [patch 24/27] fs: icache atomic inodes_stat npiggin
2009-04-25 1:20 ` [patch 25/27] fs: icache lock lru/writeback lists npiggin
2009-04-25 1:20 ` [patch 26/27] fs: icache protect inode state npiggin
2009-04-25 1:20 ` [patch 27/27] fs: icache remove inode_lock npiggin
2009-04-25 4:18 ` [patch 00/27] [rfc] vfs scalability patchset Al Viro
2009-04-25 5:02 ` Nick Piggin
2009-04-25 8:01 ` Christoph Hellwig
2009-04-25 8:06 ` Al Viro
2009-04-28 9:09 ` Christoph Hellwig
2009-04-28 9:48 ` Nick Piggin
2009-04-28 10:58 ` Peter Zijlstra
2009-04-28 11:32 ` Eric W. Biederman
2009-04-30 6:14 ` Nick Piggin
2009-04-25 19:08 ` Eric W. Biederman
2009-04-25 19:31 ` Al Viro
2009-04-25 20:29 ` Eric W. Biederman
2009-04-25 22:05 ` Theodore Tso
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090425012210.450828592@suse.de \
--to=npiggin@suse.de \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.