nfsd: create a dedicated slabcache for DRC entries

Currently we use kmalloc() which wastes a little bit of memory on each
allocation since it's a power of 2 allocator. Since we're allocating a
1024 of these now, and may need even more later, let's create a new
slabcache for them.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 13 insertions, 2 deletions

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 972c14a033ee..4aad9e4a6161 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -26,6 +26,7 @@
 static struct hlist_head *      cache_hash;
 static struct list_head         lru_head;
 static int                      cache_disabled = 1;
+static struct kmem_cache        *drc_slab;
 
 /*
  * Calculate the hash index from an XID.
@@ -51,10 +52,15 @@ int nfsd_reply_cache_init(void)
         struct svc_cacherep     *rp;
         int                     i;
 
+        drc_slab = kmem_cache_create("nfsd_drc", sizeof(struct svc_cacherep),
+                                        0, 0, NULL);
+        if (!drc_slab)
+                goto out_nomem;
+
         INIT_LIST_HEAD(&lru_head);
         i = CACHESIZE;
         while (i) {
-                rp = kmalloc(sizeof(*rp), GFP_KERNEL);
+                rp = kmem_cache_alloc(drc_slab, GFP_KERNEL);
                 if (!rp)
                         goto out_nomem;
                 list_add(&rp->c_lru, &lru_head);
@@ -85,13 +91,18 @@ void nfsd_reply_cache_shutdown(void)
                 if (rp->c_state == RC_DONE && rp->c_type == RC_REPLBUFF)
                         kfree(rp->c_replvec.iov_base);
                 list_del(&rp->c_lru);
-                kfree(rp);
+                kmem_cache_free(drc_slab, rp);
         }
 
         cache_disabled = 1;
 
         kfree (cache_hash);
         cache_hash = NULL;
+
+        if (drc_slab) {
+                kmem_cache_destroy(drc_slab);
+                drc_slab = NULL;
+        }
 }
 
 /*