Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'dcache-cleanup'
* dcache-cleanup:
vfs: get rid of insane dentry hashing rules
+18
-28
+16
-26
fs/dcache.c
+16
-26
fs/dcache.c
···
164
164
if (dentry->d_op && dentry->d_op->d_release)
165
165
dentry->d_op->d_release(dentry);
166
166
167
-
/* if dentry was never inserted into hash, immediate free is OK */
168
-
if (hlist_bl_unhashed(&dentry->d_hash))
167
+
/* if dentry was never visible to RCU, immediate free is OK */
168
+
if (!(dentry->d_flags & DCACHE_RCUACCESS))
169
169
__d_free(&dentry->d_u.d_rcu);
170
170
else
171
171
call_rcu(&dentry->d_u.d_rcu, __d_free);
···
327
327
*/
328
328
void __d_drop(struct dentry *dentry)
329
329
{
330
-
if (!(dentry->d_flags & DCACHE_UNHASHED)) {
330
+
if (!d_unhashed(dentry)) {
331
331
struct hlist_bl_head *b;
332
-
if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) {
332
+
if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED))
333
333
b = &dentry->d_sb->s_anon;
334
-
spin_lock_bucket(b);
335
-
dentry->d_flags |= DCACHE_UNHASHED;
336
-
hlist_bl_del_init(&dentry->d_hash);
337
-
spin_unlock_bucket(b);
338
-
} else {
339
-
struct hlist_bl_head *b;
334
+
else
340
335
b = d_hash(dentry->d_parent, dentry->d_name.hash);
341
-
spin_lock_bucket(b);
342
-
/*
343
-
* We may not actually need to put DCACHE_UNHASHED
344
-
* manipulations under the hash lock, but follow
345
-
* the principle of least surprise.
346
-
*/
347
-
dentry->d_flags |= DCACHE_UNHASHED;
348
-
hlist_bl_del_rcu(&dentry->d_hash);
349
-
spin_unlock_bucket(b);
350
-
dentry_rcuwalk_barrier(dentry);
351
-
}
336
+
337
+
spin_lock_bucket(b);
338
+
__hlist_bl_del(&dentry->d_hash);
339
+
dentry->d_hash.pprev = NULL;
340
+
spin_unlock_bucket(b);
341
+
342
+
dentry_rcuwalk_barrier(dentry);
352
343
}
353
344
}
354
345
EXPORT_SYMBOL(__d_drop);
···
1292
1301
dname[name->len] = 0;
1293
1302
1294
1303
dentry->d_count = 1;
1295
-
dentry->d_flags = DCACHE_UNHASHED;
1304
+
dentry->d_flags = 0;
1296
1305
spin_lock_init(&dentry->d_lock);
1297
1306
seqcount_init(&dentry->d_seq);
1298
1307
dentry->d_inode = NULL;
···
1594
1603
tmp->d_inode = inode;
1595
1604
tmp->d_flags |= DCACHE_DISCONNECTED;
1596
1605
list_add(&tmp->d_alias, &inode->i_dentry);
1597
-
bit_spin_lock(0, (unsigned long *)&tmp->d_sb->s_anon.first);
1598
-
tmp->d_flags &= ~DCACHE_UNHASHED;
1606
+
spin_lock_bucket(&tmp->d_sb->s_anon);
1599
1607
hlist_bl_add_head(&tmp->d_hash, &tmp->d_sb->s_anon);
1600
-
__bit_spin_unlock(0, (unsigned long *)&tmp->d_sb->s_anon.first);
1608
+
spin_unlock_bucket(&tmp->d_sb->s_anon);
1601
1609
spin_unlock(&tmp->d_lock);
1602
1610
spin_unlock(&inode->i_lock);
1603
1611
security_d_instantiate(tmp, inode);
···
2077
2087
{
2078
2088
BUG_ON(!d_unhashed(entry));
2079
2089
spin_lock_bucket(b);
2080
-
entry->d_flags &= ~DCACHE_UNHASHED;
2090
+
entry->d_flags |= DCACHE_RCUACCESS;
2081
2091
hlist_bl_add_head_rcu(&entry->d_hash, b);
2082
2092
spin_unlock_bucket(b);
2083
2093
}
+2
-2
include/linux/dcache.h
+2
-2
include/linux/dcache.h
···
197
197
* typically using d_splice_alias. */
198
198
199
199
#define DCACHE_REFERENCED 0x0008 /* Recently used, don't discard. */
200
-
#define DCACHE_UNHASHED 0x0010
200
+
#define DCACHE_RCUACCESS 0x0010 /* Entry has ever been RCU-visible */
201
201
#define DCACHE_INOTIFY_PARENT_WATCHED 0x0020
202
202
/* Parent inode is watched by inotify */
203
203
···
384
384
385
385
static inline int d_unhashed(struct dentry *dentry)
386
386
{
387
-
return (dentry->d_flags & DCACHE_UNHASHED);
387
+
return hlist_bl_unhashed(&dentry->d_hash);
388
388
}
389
389
390
390
static inline int d_unlinked(struct dentry *dentry)