[PATCH] knfsd: Unexport cache_fresh and fix a small race
Cache_fresh is now only used in cache.c, so unexport it.
Part of cache_fresh (setting CACHE_VALID) should really be done under the
lock, while part (calling cache_revisit_request etc) must be done outside the
lock. So we split it up appropriately.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index b242f49..edcda4f 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -96,6 +96,27 @@
}
EXPORT_SYMBOL(sunrpc_cache_lookup);
+
+static void queue_loose(struct cache_detail *detail, struct cache_head *ch);
+
+static int cache_fresh_locked(struct cache_head *head, time_t expiry)
+{
+ head->expiry_time = expiry;
+ head->last_refresh = get_seconds();
+ return !test_and_set_bit(CACHE_VALID, &head->flags);
+}
+
+static void cache_fresh_unlocked(struct cache_head *head,
+ struct cache_detail *detail, int new)
+{
+ if (new)
+ cache_revisit_request(head);
+ if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
+ cache_revisit_request(head);
+ queue_loose(detail, head);
+ }
+}
+
struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
struct cache_head *new, struct cache_head *old, int hash)
{
@@ -105,6 +126,7 @@
*/
struct cache_head **head;
struct cache_head *tmp;
+ int is_new;
if (!test_bit(CACHE_VALID, &old->flags)) {
write_lock(&detail->hash_lock);
@@ -113,9 +135,9 @@
set_bit(CACHE_NEGATIVE, &old->flags);
else
detail->update(old, new);
- /* FIXME cache_fresh should come first */
+ is_new = cache_fresh_locked(old, new->expiry_time);
write_unlock(&detail->hash_lock);
- cache_fresh(detail, old, new->expiry_time);
+ cache_fresh_unlocked(old, detail, is_new);
return old;
}
write_unlock(&detail->hash_lock);
@@ -138,9 +160,11 @@
tmp->next = *head;
*head = tmp;
cache_get(tmp);
+ is_new = cache_fresh_locked(tmp, new->expiry_time);
+ cache_fresh_locked(old, 0);
write_unlock(&detail->hash_lock);
- cache_fresh(detail, tmp, new->expiry_time);
- cache_fresh(detail, old, 0);
+ cache_fresh_unlocked(tmp, detail, is_new);
+ cache_fresh_unlocked(old, detail, 0);
detail->cache_put(old, detail);
return tmp;
}
@@ -192,7 +216,8 @@
clear_bit(CACHE_PENDING, &h->flags);
if (rv == -EAGAIN) {
set_bit(CACHE_NEGATIVE, &h->flags);
- cache_fresh(detail, h, get_seconds()+CACHE_NEW_EXPIRY);
+ cache_fresh_unlocked(h, detail,
+ cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY));
rv = -ENOENT;
}
break;
@@ -213,22 +238,6 @@
return rv;
}
-static void queue_loose(struct cache_detail *detail, struct cache_head *ch);
-
-void cache_fresh(struct cache_detail *detail,
- struct cache_head *head, time_t expiry)
-{
-
- head->expiry_time = expiry;
- head->last_refresh = get_seconds();
- if (!test_and_set_bit(CACHE_VALID, &head->flags))
- cache_revisit_request(head);
- if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
- cache_revisit_request(head);
- queue_loose(detail, head);
- }
-}
-
/*
* caches need to be periodically cleaned.
* For this we maintain a list of cache_detail and
