[PATCH v2 5/8] nfsd: when updating an entry with RC_NOCACHE, just free it

Jeff Layton
2013-02-04T13:18:23Z

There's no need to keep entries around that we're declaring RC_NOCACHE.
Ditto if there's a problem with the entry.

With this change too, there's no need to test for RC_UNUSED in the
search function. If the entry's in the hash table then it's either
INPROG or DONE.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
fs/nfsd/nfscache.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 69d29d4..e8ea785 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -98,6 +98,14 @@ nfsd_reply_cache_free_locked(struct svc_cacherep *rp)
kmem_cache_free(drc_slab, rp);
}

+static void
+nfsd_reply_cache_free(struct svc_cacherep *rp)
+{
+ spin_lock(&cache_lock);
+ nfsd_reply_cache_free_locked(rp);
+ spin_unlock(&cache_lock);
+}
+
int nfsd_reply_cache_init(void)
{
drc_slab = kmem_cache_create("nfsd_drc", sizeof(struct svc_cacherep),
@@ -182,8 +190,7 @@ nfsd_cache_search(struct svc_rqst *rqstp)

rh = &cache_hash[request_hash(xid)];
hlist_for_each_entry(rp, hn, rh, c_hash) {
- if (rp->c_state != RC_UNUSED &&
- xid == rp->c_xid && proc == rp->c_proc &&
+ if (xid == rp->c_xid && proc == rp->c_proc &&
proto == rp->c_prot && vers == rp->c_vers &&
!nfsd_cache_entry_expired(rp) &&
rpc_cmp_addr(svc_addr(rqstp), (struct sockaddr *)&rp->c_addr) &&
@@ -353,7 +360,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)

/* Don't cache excessive amounts of data and XDR failures */
if (!statp || len > (256 >> 2)) {
- rp->c_state = RC_UNUSED;
+ nfsd_reply_cache_free(rp);
return;
}

@@ -367,12 +374,15 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
cachv = &rp->c_replvec;
cachv->iov_base = kmalloc(len << 2, GFP_KERNEL);
if (!cachv->iov_base) {
- rp->c_state = RC_UNUSED;
+ nfsd_reply_cache_free(rp);
return;
}
cachv->iov_len = len << 2;
memcpy(cachv->iov_base, statp, len << 2);
break;
+ case RC_NOCACHE:
+ nfsd_reply_cache_free(rp);
+ return;
}
spin_lock(&cache_lock);
lru_put_end(rp);
--
1.7.11.7