diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-28 22:26:31 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-28 22:26:31 +0300 |
| commit | 554828ee0db41618d101d9549db8808af9fd9d65 (patch) | |
| tree | 8a3e3022c084f7c7c1eebc494a1b94f0ee0d5cae /fs/affs/namei.c | |
| parent | 194dc870a5890e855ecffb30f3b80ba7c88f96d6 (diff) | |
| parent | 703b5faf22fbddf984a361e6555f3a03fdba63d9 (diff) | |
| download | linux-554828ee0db41618d101d9549db8808af9fd9d65.tar.xz | |
Merge branch 'salted-string-hash'
This changes the vfs dentry hashing to mix in the parent pointer at the
_beginning_ of the hash, rather than at the end.
That actually improves both the hash and the code generation, because we
can move more of the computation to the "static" part of the dcache
setup, and do less at lookup runtime.
It turns out that a lot of other hash users also really wanted to mix in
a base pointer as a 'salt' for the hash, and so the slightly extended
interface ends up working well for other cases too.
Users that want a string hash that is purely about the string pass in a
'salt' pointer of NULL.
* merge branch 'salted-string-hash':
fs/dcache.c: Save one 32-bit multiply in dcache lookup
vfs: make the string hashes salt the hash
Diffstat (limited to 'fs/affs/namei.c')
| -rw-r--r-- | fs/affs/namei.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/affs/namei.c b/fs/affs/namei.c index 00d3002a6780..eb32029bc776 100644 --- a/fs/affs/namei.c +++ b/fs/affs/namei.c @@ -61,7 +61,7 @@ affs_get_toupper(struct super_block *sb) * Note: the dentry argument is the parent dentry. */ static inline int -__affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate) +__affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr, toupper_t toupper, bool notruncate) { const u8 *name = qstr->name; unsigned long hash; @@ -72,7 +72,7 @@ __affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate) if (retval) return retval; - hash = init_name_hash(); + hash = init_name_hash(dentry); len = min(qstr->len, AFFSNAMEMAX); for (; len > 0; name++, len--) hash = partial_name_hash(toupper(*name), hash); @@ -84,7 +84,7 @@ __affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate) static int affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr) { - return __affs_hash_dentry(qstr, affs_toupper, + return __affs_hash_dentry(dentry, qstr, affs_toupper, affs_nofilenametruncate(dentry)); } @@ -92,7 +92,7 @@ affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr) static int affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr) { - return __affs_hash_dentry(qstr, affs_intl_toupper, + return __affs_hash_dentry(dentry, qstr, affs_intl_toupper, affs_nofilenametruncate(dentry)); } |