diff options
| author | David Howells <dhowells@redhat.com> | 2013-09-21 00:09:31 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2013-09-27 18:40:25 +0100 |
| commit | 8fb883f3e30065529e4f35d4b4f355193dcdb7a2 (patch) | |
| tree | 2a1096b66c9465539fb6e13daa16137d730f3ea3 /fs/fscache/cookie.c | |
| parent | 2457aaf73a97a97c8596ed3903bd09601976f3bc (diff) | |
FS-Cache: Add use/unuse/wake cookie wrappers
Add wrapper functions for dealing with cookie->n_active:
(*) __fscache_use_cookie() to increment it.
(*) __fscache_unuse_cookie() to decrement and test against zero.
(*) __fscache_wake_unused_cookie() to wake up anyone waiting for it to reach
zero.
The second and third are split so that the third can be done after cookie->lock
has been released in case the waiter wakes up whilst we're still holding it and
tries to get it.
We will need to wake-on-zero once the cookie disablement patch is applied
because it will then be possible to see n_active become zero without the cookie
being relinquished.
Also move the cookie usement out of fscache_attr_changed_op() and into
fscache_attr_changed() and the operation struct so that cookie disablement
will be able to track it.
Whilst we're at it, only increment n_active if we're about to do
fscache_submit_op() so that we don't have to deal with undoing it if anything
earlier fails. Possibly this should be moved into fscache_submit_op() which
could look at FSCACHE_OP_UNUSE_COOKIE.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'fs/fscache/cookie.c')
| -rw-r--r-- | fs/fscache/cookie.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index b2a86e324aa..d851aa555d2 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -568,6 +568,7 @@ int __fscache_check_consistency(struct fscache_cookie *cookie) { struct fscache_operation *op; struct fscache_object *object; + bool wake_cookie = false; int ret; _enter("%p,", cookie); @@ -600,7 +601,7 @@ int __fscache_check_consistency(struct fscache_cookie *cookie) op->debug_id = atomic_inc_return(&fscache_op_debug_id); - atomic_inc(&cookie->n_active); + __fscache_use_cookie(cookie); if (fscache_submit_op(object, op) < 0) goto submit_failed; @@ -622,9 +623,11 @@ int __fscache_check_consistency(struct fscache_cookie *cookie) return ret; submit_failed: - atomic_dec(&cookie->n_active); + wake_cookie = __fscache_unuse_cookie(cookie); inconsistent: spin_unlock(&cookie->lock); + if (wake_cookie) + __fscache_wake_unused_cookie(cookie); kfree(op); _leave(" = -ESTALE"); return -ESTALE; |