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Diffstat (limited to 'net/sunrpc/cache.c')
-rw-r--r--net/sunrpc/cache.c109
1 files changed, 61 insertions, 48 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 45cdaff9b36..d6eee291a0e 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -103,23 +103,21 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
-static void queue_loose(struct cache_detail *detail, struct cache_head *ch);
+static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
-static int cache_fresh_locked(struct cache_head *head, time_t expiry)
+static void 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);
+ set_bit(CACHE_VALID, &head->flags);
}
static void cache_fresh_unlocked(struct cache_head *head,
- struct cache_detail *detail, int new)
+ struct cache_detail *detail)
{
- if (new)
- cache_revisit_request(head);
if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
cache_revisit_request(head);
- queue_loose(detail, head);
+ cache_dequeue(detail, head);
}
}
@@ -132,7 +130,6 @@ 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);
@@ -141,9 +138,9 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
set_bit(CACHE_NEGATIVE, &old->flags);
else
detail->update(old, new);
- is_new = cache_fresh_locked(old, new->expiry_time);
+ cache_fresh_locked(old, new->expiry_time);
write_unlock(&detail->hash_lock);
- cache_fresh_unlocked(old, detail, is_new);
+ cache_fresh_unlocked(old, detail);
return old;
}
write_unlock(&detail->hash_lock);
@@ -167,11 +164,11 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
*head = tmp;
detail->entries++;
cache_get(tmp);
- is_new = cache_fresh_locked(tmp, new->expiry_time);
+ cache_fresh_locked(tmp, new->expiry_time);
cache_fresh_locked(old, 0);
write_unlock(&detail->hash_lock);
- cache_fresh_unlocked(tmp, detail, is_new);
- cache_fresh_unlocked(old, detail, 0);
+ cache_fresh_unlocked(tmp, detail);
+ cache_fresh_unlocked(old, detail);
cache_put(old, detail);
return tmp;
}
@@ -184,6 +181,22 @@ static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
return cd->cache_upcall(cd, h);
}
+static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
+{
+ if (!test_bit(CACHE_VALID, &h->flags) ||
+ h->expiry_time < get_seconds())
+ return -EAGAIN;
+ else if (detail->flush_time > h->last_refresh)
+ return -EAGAIN;
+ else {
+ /* entry is valid */
+ if (test_bit(CACHE_NEGATIVE, &h->flags))
+ return -ENOENT;
+ else
+ return 0;
+ }
+}
+
/*
* This is the generic cache management routine for all
* the authentication caches.
@@ -192,8 +205,10 @@ static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
*
*
* Returns 0 if the cache_head can be used, or cache_puts it and returns
- * -EAGAIN if upcall is pending,
- * -ETIMEDOUT if upcall failed and should be retried,
+ * -EAGAIN if upcall is pending and request has been queued
+ * -ETIMEDOUT if upcall failed or request could not be queue or
+ * upcall completed but item is still invalid (implying that
+ * the cache item has been replaced with a newer one).
* -ENOENT if cache entry was negative
*/
int cache_check(struct cache_detail *detail,
@@ -203,17 +218,7 @@ int cache_check(struct cache_detail *detail,
long refresh_age, age;
/* First decide return status as best we can */
- if (!test_bit(CACHE_VALID, &h->flags) ||
- h->expiry_time < get_seconds())
- rv = -EAGAIN;
- else if (detail->flush_time > h->last_refresh)
- rv = -EAGAIN;
- else {
- /* entry is valid */
- if (test_bit(CACHE_NEGATIVE, &h->flags))
- rv = -ENOENT;
- else rv = 0;
- }
+ rv = cache_is_valid(detail, h);
/* now see if we want to start an upcall */
refresh_age = (h->expiry_time - h->last_refresh);
@@ -229,10 +234,11 @@ int cache_check(struct cache_detail *detail,
switch (cache_make_upcall(detail, h)) {
case -EINVAL:
clear_bit(CACHE_PENDING, &h->flags);
+ cache_revisit_request(h);
if (rv == -EAGAIN) {
set_bit(CACHE_NEGATIVE, &h->flags);
- cache_fresh_unlocked(h, detail,
- cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY));
+ cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
+ cache_fresh_unlocked(h, detail);
rv = -ENOENT;
}
break;
@@ -245,10 +251,14 @@ int cache_check(struct cache_detail *detail,
}
}
- if (rv == -EAGAIN)
- if (cache_defer_req(rqstp, h) != 0)
- rv = -ETIMEDOUT;
-
+ if (rv == -EAGAIN) {
+ if (cache_defer_req(rqstp, h) < 0) {
+ /* Request is not deferred */
+ rv = cache_is_valid(detail, h);
+ if (rv == -EAGAIN)
+ rv = -ETIMEDOUT;
+ }
+ }
if (rv)
cache_put(h, detail);
return rv;
@@ -396,7 +406,7 @@ static int cache_clean(void)
)
continue;
if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
- queue_loose(current_detail, ch);
+ cache_dequeue(current_detail, ch);
if (atomic_read(&ch->ref.refcount) == 1)
break;
@@ -412,8 +422,10 @@ static int cache_clean(void)
if (!ch)
current_index ++;
spin_unlock(&cache_list_lock);
- if (ch)
+ if (ch) {
+ cache_revisit_request(ch);
cache_put(ch, d);
+ }
} else
spin_unlock(&cache_list_lock);
@@ -488,7 +500,7 @@ static int cache_defer_cnt;
static int cache_defer_req(struct cache_req *req, struct cache_head *item)
{
- struct cache_deferred_req *dreq;
+ struct cache_deferred_req *dreq, *discard;
int hash = DFR_HASH(item);
if (cache_defer_cnt >= DFR_MAX) {
@@ -496,11 +508,11 @@ static int cache_defer_req(struct cache_req *req, struct cache_head *item)
* or continue and drop the oldest below
*/
if (net_random()&1)
- return -ETIMEDOUT;
+ return -ENOMEM;
}
dreq = req->defer(req);
if (dreq == NULL)
- return -ETIMEDOUT;
+ return -ENOMEM;
dreq->item = item;
@@ -513,23 +525,24 @@ static int cache_defer_req(struct cache_req *req, struct cache_head *item)
list_add(&dreq->hash, &cache_defer_hash[hash]);
/* it is in, now maybe clean up */
- dreq = NULL;
+ discard = NULL;
if (++cache_defer_cnt > DFR_MAX) {
- dreq = list_entry(cache_defer_list.prev,
- struct cache_deferred_req, recent);
- list_del(&dreq->recent);
- list_del(&dreq->hash);
+ discard = list_entry(cache_defer_list.prev,
+ struct cache_deferred_req, recent);
+ list_del_init(&discard->recent);
+ list_del_init(&discard->hash);
cache_defer_cnt--;
}
spin_unlock(&cache_defer_lock);
- if (dreq) {
+ if (discard)
/* there was one too many */
- dreq->revisit(dreq, 1);
- }
+ discard->revisit(discard, 1);
+
if (!test_bit(CACHE_PENDING, &item->flags)) {
/* must have just been validated... */
cache_revisit_request(item);
+ return -EAGAIN;
}
return 0;
}
@@ -551,7 +564,7 @@ static void cache_revisit_request(struct cache_head *item)
dreq = list_entry(lp, struct cache_deferred_req, hash);
lp = lp->next;
if (dreq->item == item) {
- list_del(&dreq->hash);
+ list_del_init(&dreq->hash);
list_move(&dreq->recent, &pending);
cache_defer_cnt--;
}
@@ -577,7 +590,7 @@ void cache_clean_deferred(void *owner)
list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) {
if (dreq->owner == owner) {
- list_del(&dreq->hash);
+ list_del_init(&dreq->hash);
list_move(&dreq->recent, &pending);
cache_defer_cnt--;
}
@@ -887,7 +900,7 @@ static int cache_release(struct inode *inode, struct file *filp,
-static void queue_loose(struct cache_detail *detail, struct cache_head *ch)
+static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
{
struct cache_queue *cq;
spin_lock(&queue_lock);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-30 17:48:33 +0000