X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=net%2Fsunrpc%2Fcache.c;h=00cb388ece032cec8aeba948bb97c0e653eede5e;hb=1a047060a99f274a7c52cfea8159e4142a14b8a7;hp=4449dc52edf5bcd4094c49dc2ece8fe5de2a87b7;hpb=15a5f6bd23eddd5b3be80366f364be04fb1c1c99;p=linux-2.6-omap-h63xx.git diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 4449dc52edf..00cb388ece0 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -37,12 +37,12 @@ static void cache_defer_req(struct cache_req *req, struct cache_head *item); static void cache_revisit_request(struct cache_head *item); -void cache_init(struct cache_head *h) +static void cache_init(struct cache_head *h) { time_t now = get_seconds(); h->next = NULL; h->flags = 0; - atomic_set(&h->refcnt, 1); + kref_init(&h->ref); h->expiry_time = now + CACHE_NEW_EXPIRY; h->last_refresh = now; } @@ -71,7 +71,12 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, new = detail->alloc(); if (!new) return NULL; + /* must fully initialise 'new', else + * we might get lose if we need to + * cache_put it soon. + */ cache_init(new); + detail->init(new, key); write_lock(&detail->hash_lock); @@ -81,11 +86,10 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, if (detail->match(tmp, key)) { cache_get(tmp); write_unlock(&detail->hash_lock); - detail->cache_put(new, detail); + cache_put(new, detail); return tmp; } } - detail->init(new, key); new->next = *head; *head = new; detail->entries++; @@ -96,6 +100,27 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, } 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 +130,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, */ 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 +139,9 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, 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); @@ -123,7 +149,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, /* We need to insert a new entry */ tmp = detail->alloc(); if (!tmp) { - detail->cache_put(old, detail); + cache_put(old, detail); return NULL; } cache_init(tmp); @@ -137,11 +163,14 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, detail->update(tmp, new); tmp->next = *head; *head = tmp; + detail->entries++; 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); - detail->cache_put(old, detail); + cache_fresh_unlocked(tmp, detail, is_new); + cache_fresh_unlocked(old, detail, 0); + cache_put(old, detail); return tmp; } EXPORT_SYMBOL(sunrpc_cache_update); @@ -192,7 +221,8 @@ int cache_check(struct cache_detail *detail, 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; @@ -208,25 +238,11 @@ int cache_check(struct cache_detail *detail, if (rv == -EAGAIN) cache_defer_req(rqstp, h); - if (rv && h) - detail->cache_put(h, detail); + if (rv) + cache_put(h, detail); 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)) - queue_loose(detail, head); -} - /* * caches need to be periodically cleaned. * For this we maintain a list of cache_detail and @@ -420,7 +436,7 @@ static int cache_clean(void) if (test_and_clear_bit(CACHE_PENDING, &ch->flags)) queue_loose(current_detail, ch); - if (atomic_read(&ch->refcnt) == 1) + if (atomic_read(&ch->ref.refcount) == 1) break; } if (ch) { @@ -435,7 +451,7 @@ static int cache_clean(void) current_index ++; spin_unlock(&cache_list_lock); if (ch) - d->cache_put(ch, d); + cache_put(ch, d); } else spin_unlock(&cache_list_lock); @@ -551,7 +567,7 @@ static void cache_defer_req(struct cache_req *req, struct cache_head *item) /* there was one too many */ dreq->revisit(dreq, 1); } - if (test_bit(CACHE_VALID, &item->flags)) { + if (!test_bit(CACHE_PENDING, &item->flags)) { /* must have just been validated... */ cache_revisit_request(item); } @@ -712,7 +728,7 @@ cache_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) !test_bit(CACHE_PENDING, &rq->item->flags)) { list_del(&rq->q.list); spin_unlock(&queue_lock); - cd->cache_put(rq->item, cd); + cache_put(rq->item, cd); kfree(rq->buf); kfree(rq); } else @@ -892,10 +908,10 @@ static void queue_loose(struct cache_detail *detail, struct cache_head *ch) if (cr->item != ch) continue; if (cr->readers != 0) - break; + continue; list_del(&cr->q.list); spin_unlock(&queue_lock); - detail->cache_put(cr->item, detail); + cache_put(cr->item, detail); kfree(cr->buf); kfree(cr); return; @@ -1180,8 +1196,8 @@ static int c_show(struct seq_file *m, void *p) return cd->cache_show(m, cd, NULL); ifdebug(CACHE) - seq_printf(m, "# expiry=%ld refcnt=%d\n", - cp->expiry_time, atomic_read(&cp->refcnt)); + seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n", + cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags); cache_get(cp); if (cache_check(cd, cp, NULL)) /* cache_check does a cache_put on failure */