Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
---
fs/nfsd/nfscache.c | 73 +++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 50 insertions(+), 23 deletions(-)
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index c9e25bc7ea56..a387d443641f 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -29,10 +29,10 @@
struct nfsd_drc_bucket {
struct hlist_head cache_hash;
+ struct list_head lru_head;
};
static struct nfsd_drc_bucket *drc_hashtbl;
-static struct list_head lru_head;
static struct kmem_cache *drc_slab;
/* max number of entries allowed in the cache */
@@ -40,6 +40,7 @@ static unsigned int max_drc_entries;
/* number of significant bits in the hash value */
static unsigned int maskbits;
+static unsigned int drc_hashsize;
/*
* Stats and other tracking of on the duplicate reply cache. All of these and
@@ -167,8 +168,8 @@ nfsd_reply_cache_free(struct svc_cacherep *rp)
int nfsd_reply_cache_init(void)
{
unsigned int hashsize;
+ unsigned int i;
- INIT_LIST_HEAD(&lru_head);
max_drc_entries = nfsd_cache_size_limit();
num_drc_entries = 0;
hashsize = nfsd_hashsize(max_drc_entries);
@@ -183,6 +184,9 @@ int nfsd_reply_cache_init(void)
drc_hashtbl = kcalloc(hashsize, sizeof(*drc_hashtbl), GFP_KERNEL);
if (!drc_hashtbl)
goto out_nomem;
+ for (i = 0; i < hashsize; i++)
+ INIT_LIST_HEAD(&drc_hashtbl[i].lru_head);
+ drc_hashsize = hashsize;
return 0;
out_nomem:
@@ -194,17 +198,22 @@ out_nomem:
void nfsd_reply_cache_shutdown(void)
{
struct svc_cacherep *rp;
+ unsigned int i;
unregister_shrinker(&nfsd_reply_cache_shrinker);
cancel_delayed_work_sync(&cache_cleaner);
- while (!list_empty(&lru_head)) {
- rp = list_entry(lru_head.next, struct svc_cacherep, c_lru);
- nfsd_reply_cache_free_locked(rp);
+ for (i = 0; i < drc_hashsize; i++) {
+ struct list_head *head = &drc_hashtbl[i].lru_head;
+ while (!list_empty(head)) {
+ rp = list_first_entry(head, struct svc_cacherep, c_lru);
+ nfsd_reply_cache_free_locked(rp);
+ }
}
kfree (drc_hashtbl);
drc_hashtbl = NULL;
+ drc_hashsize = 0;
if (drc_slab) {
kmem_cache_destroy(drc_slab);
@@ -217,10 +226,10 @@ void nfsd_reply_cache_shutdown(void)
* not already scheduled.
*/
static void
-lru_put_end(struct svc_cacherep *rp)
+lru_put_end(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
{
rp->c_timestamp = jiffies;
- list_move_tail(&rp->c_lru, &lru_head);
+ list_move_tail(&rp->c_lru, &b->lru_head);
schedule_delayed_work(&cache_cleaner, RC_EXPIRE);
}
@@ -234,17 +243,13 @@ hash_refile(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
hlist_add_head(&rp->c_hash, &b->cache_hash);
}
-/*
- * Walk the LRU list and prune off entries that are older than RC_EXPIRE.
- * Also prune the oldest ones when the total exceeds the max number of entries.
- */
static long
-prune_cache_entries(void)
+prune_bucket(struct nfsd_drc_bucket *b)
{
struct svc_cacherep *rp, *tmp;
long freed = 0;
- list_for_each_entry_safe(rp, tmp, &lru_head, c_lru) {
+ list_for_each_entry_safe(rp, tmp, &b->lru_head, c_lru) {
/*
* Don't free entries attached to calls that are still
* in-progress, but do keep scanning the list.
@@ -257,16 +262,33 @@ prune_cache_entries(void)
nfsd_reply_cache_free_locked(rp);
freed++;
}
+ return freed;
+}
+
+/*
+ * Walk the LRU list and prune off entries that are older than RC_EXPIRE.
+ * Also prune the oldest ones when the total exceeds the max number of entries.
+ */
+static long
+prune_cache_entries(void)
+{
+ unsigned int i;
+ long freed = 0;
+ bool cancel = true;
+
+ for (i = 0; i < drc_hashsize; i++) {
+ struct nfsd_drc_bucket *b = &drc_hashtbl[i];
+
+ freed += prune_bucket(b);
+ if (!list_empty(&b->lru_head))
+ cancel = false;
+ }
/*
- * Conditionally rearm the job. If we cleaned out the list, then
- * cancel any pending run (since there won't be any work to do).
- * Otherwise, we rearm the job or modify the existing one to run in
- * RC_EXPIRE since we just ran the pruner.
+ * Conditionally rearm the job to run in RC_EXPIRE since we just
+ * ran the pruner.
*/
- if (list_empty(&lru_head))
- cancel_delayed_work(&cache_cleaner);
- else
+ if (!cancel)
mod_delayed_work(system_wq, &cache_cleaner, RC_EXPIRE);
return freed;
}
@@ -458,7 +480,7 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
rp->c_csum = csum;
hash_refile(b, rp);
- lru_put_end(rp);
+ lru_put_end(b, rp);
/* release any buffer */
if (rp->c_type == RC_REPLBUFF) {
@@ -475,7 +497,7 @@ found_entry:
nfsdstats.rchits++;
/* We found a matching entry which is either in progress or done. */
age = jiffies - rp->c_timestamp;
- lru_put_end(rp);
+ lru_put_end(b, rp);
rtn = RC_DROPIT;
/* Request being processed or excessive rexmits */
@@ -530,12 +552,17 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
{
struct svc_cacherep *rp = rqstp->rq_cacherep;
struct kvec *resv = &rqstp->rq_res.head[0], *cachv;
+ u32 hash;
+ struct nfsd_drc_bucket *b;
int len;
size_t bufsize = 0;
if (!rp)
return;
+ hash = nfsd_cache_hash(rp->c_xid);
+ b = &drc_hashtbl[hash];
+
len = resv->iov_len - ((char*)statp - (char*)resv->iov_base);
len >>= 2;
@@ -568,7 +595,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
}
spin_lock(&cache_lock);
drc_mem_usage += bufsize;
- lru_put_end(rp);
+ lru_put_end(b, rp);
rp->c_secure = rqstp->rq_secure;
rp->c_type = cachetype;
rp->c_state = RC_DONE;
--
1.9.3
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