diff options
| author | Andrew Morton <akpm@osdl.org> | 2006-03-24 03:15:47 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-24 07:33:20 -0800 |
| commit | 36f574135e36b86bb6ae794bf1d0fce3efa5601f (patch) | |
| tree | 9dd55b2244d2ac9f7e05098e7236aa8cf6cd6d60 /kernel/user.c | |
| parent | 3cf64b933c90ba701cfdc7188431104c646d7c9e (diff) | |
| download | lwn-36f574135e36b86bb6ae794bf1d0fce3efa5601f.tar.gz lwn-36f574135e36b86bb6ae794bf1d0fce3efa5601f.zip | |
[PATCH] free_uid() locking improvement
Reduce lock hold times in free_uid().
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/user.c')
| -rw-r--r-- | kernel/user.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/kernel/user.c b/kernel/user.c index d9deae43a9ab..2116642f42c6 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -105,15 +105,19 @@ void free_uid(struct user_struct *up) { unsigned long flags; + if (!up) + return; + local_irq_save(flags); - if (up && atomic_dec_and_lock(&up->__count, &uidhash_lock)) { + if (atomic_dec_and_lock(&up->__count, &uidhash_lock)) { uid_hash_remove(up); + spin_unlock_irqrestore(&uidhash_lock, flags); key_put(up->uid_keyring); key_put(up->session_keyring); kmem_cache_free(uid_cachep, up); - spin_unlock(&uidhash_lock); + } else { + local_irq_restore(flags); } - local_irq_restore(flags); } struct user_struct * alloc_uid(uid_t uid) |