Commit ed00c2f6 authored by Trond Myklebust's avatar Trond Myklebust Committed by J. Bruce Fields
Browse files

knfsd: Further simplify the cache lookup 



Order the structure so that the key can be compared using memcmp().

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent 76ecec21

fs/nfsd/cache.h

+11 −8
Original line number Diff line number Diff line
@@ -19,18 +19,21 @@ 
 * is much larger than a sockaddr_in6.

 */

struct svc_cacherep {

	struct list_head	c_lru;

	struct {

		/* Keep often-read xid, csum in the same cache line: */

		__be32			k_xid;

		__wsum			k_csum;

		u32			k_proc;

		u32			k_prot;

		u32			k_vers;

		unsigned int		k_len;

		struct sockaddr_in6	k_addr;

	} c_key;



	struct list_head	c_lru;

	unsigned char		c_state,	/* unused, inprog, done */

				c_type,		/* status, buffer */

				c_secure : 1;	/* req came from port < 1024 */

	struct sockaddr_in6	c_addr;

	__be32			c_xid;

	u32			c_prot;

	u32			c_proc;

	u32			c_vers;

	unsigned int		c_len;

	__wsum			c_csum;

	unsigned long		c_timestamp;

	union {

		struct kvec	u_vec;

fs/nfsd/nfscache.c

+16 −29
Original line number Diff line number Diff line
@@ -131,15 +131,15 @@ nfsd_reply_cache_alloc(struct svc_rqst *rqstp, __wsum csum) 
		rp->c_type = RC_NOCACHE;

		INIT_LIST_HEAD(&rp->c_lru);



		rp->c_xid = rqstp->rq_xid;

		rp->c_proc = rqstp->rq_proc;

		memset(&rp->c_addr, 0, sizeof(rp->c_addr));

		rpc_copy_addr((struct sockaddr *)&rp->c_addr, svc_addr(rqstp));

		rpc_set_port((struct sockaddr *)&rp->c_addr, rpc_get_port(svc_addr(rqstp)));

		rp->c_prot = rqstp->rq_prot;

		rp->c_vers = rqstp->rq_vers;

		rp->c_len = rqstp->rq_arg.len;

		rp->c_csum = csum;

		memset(&rp->c_key, 0, sizeof(rp->c_key));

		rp->c_key.k_xid = rqstp->rq_xid;

		rp->c_key.k_proc = rqstp->rq_proc;

		rpc_copy_addr((struct sockaddr *)&rp->c_key.k_addr, svc_addr(rqstp));

		rpc_set_port((struct sockaddr *)&rp->c_key.k_addr, rpc_get_port(svc_addr(rqstp)));

		rp->c_key.k_prot = rqstp->rq_prot;

		rp->c_key.k_vers = rqstp->rq_vers;

		rp->c_key.k_len = rqstp->rq_arg.len;

		rp->c_key.k_csum = csum;

	}

	return rp;

}
@@ -330,27 +330,14 @@ nfsd_cache_csum(struct svc_rqst *rqstp) 
	return csum;

}



static bool

nfsd_cache_match(const struct svc_cacherep *key, const struct svc_cacherep *rp)

static int

nfsd_cache_key_cmp(const struct svc_cacherep *key, const struct svc_cacherep *rp)

{

	/* Check RPC XID first */

	if (key->c_xid != rp->c_xid)

		return false;

	/* compare checksum of NFS data */

	if (key->c_csum != rp->c_csum) {

	if (key->c_key.k_xid == rp->c_key.k_xid &&

	    key->c_key.k_csum != rp->c_key.k_csum)

		++payload_misses;

		return false;

	}



	/* Other discriminators */

	if (key->c_proc != rp->c_proc ||

	    key->c_prot != rp->c_prot ||

	    key->c_vers != rp->c_vers ||

	    key->c_len != rp->c_len ||

	    memcmp(&key->c_addr, &rp->c_addr, sizeof(key->c_addr)) != 0)

		return false;



	return true;

	return memcmp(&key->c_key, &rp->c_key, sizeof(key->c_key));

}



/*
@@ -367,7 +354,7 @@ nfsd_cache_insert(struct nfsd_drc_bucket *b, struct svc_cacherep *key) 


	list_for_each_entry(rp, rh, c_lru) {

		++entries;

		if (nfsd_cache_match(key, rp)) {

		if (nfsd_cache_key_cmp(key, rp) == 0) {

			ret = rp;

			break;

		}
@@ -510,7 +497,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp) 
	if (!rp)

		return;



	hash = nfsd_cache_hash(rp->c_xid);

	hash = nfsd_cache_hash(rp->c_key.k_xid);

	b = &drc_hashtbl[hash];



	len = resv->iov_len - ((char*)statp - (char*)resv->iov_base);