From: Chuck Lever <chuck.lever@oracle.com>
To: bfields@fieldses.org
Cc: linux-nfs@vger.kernel.org
Subject: [PATCH v2 08/11] NFSD: Refactor nfsd_dispatch() error paths
Date: Tue, 29 Sep 2020 10:04:19 -0400 [thread overview]
Message-ID: <160138825933.2558.7100398429811622816.stgit@klimt.1015granger.net> (raw)
In-Reply-To: <160138785101.2558.11821923574884893011.stgit@klimt.1015granger.net>
nfsd_dispatch() is a hot path. Ensure the compiler takes the
processing of infrequent errors out of line.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
fs/nfsd/nfssvc.c | 60 ++++++++++++++++++++++++++++++++----------------------
1 file changed, 35 insertions(+), 25 deletions(-)
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 18ec22a8580a..283d29ecae43 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -1021,29 +1021,24 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
dprintk("nfsd_dispatch: vers %d proc %d\n",
rqstp->rq_vers, rqstp->rq_proc);
- if (nfs_request_too_big(rqstp, proc)) {
- dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers);
- *statp = rpc_garbage_args;
- return 1;
- }
+ if (nfs_request_too_big(rqstp, proc))
+ goto out_too_large;
+
/*
* Give the xdr decoder a chance to change this if it wants
* (necessary in the NFSv4.0 compound case)
*/
rqstp->rq_cachetype = proc->pc_cachetype;
- if (!proc->pc_decode(rqstp, argv->iov_base)) {
- dprintk("nfsd: failed to decode arguments!\n");
- *statp = rpc_garbage_args;
- return 1;
- }
+ if (!proc->pc_decode(rqstp, argv->iov_base))
+ goto out_decode_err;
switch (nfsd_cache_lookup(rqstp)) {
case RC_DOIT:
break;
case RC_REPLY:
- return 1;
+ goto out_cached_reply;
case RC_DROPIT:
- return 0;
+ goto out_dropit;
}
/*
@@ -1055,11 +1050,8 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
nfserr = proc->pc_func(rqstp);
nfserr = map_new_errors(rqstp->rq_vers, nfserr);
- if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) {
- dprintk("nfsd: Dropping request; may be revisited later\n");
- nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
- return 0;
- }
+ if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags))
+ goto out_update_drop;
if (rqstp->rq_proc != 0)
*p++ = nfserr;
@@ -1067,16 +1059,34 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
/*
* For NFSv2, additional info is never returned in case of an error.
*/
- if (!(nfserr && rqstp->rq_vers == 2)) {
- if (!proc->pc_encode(rqstp, p)) {
- dprintk("nfsd: failed to encode result!\n");
- nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
- *statp = rpc_system_err;
- return 1;
- }
- }
+ if (!(nfserr && rqstp->rq_vers == 2))
+ if (!proc->pc_encode(rqstp, p))
+ goto out_encode_err;
nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
+out_cached_reply:
+ return 1;
+
+out_too_large:
+ dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers);
+ *statp = rpc_garbage_args;
+ return 1;
+
+out_decode_err:
+ dprintk("nfsd: failed to decode arguments!\n");
+ *statp = rpc_garbage_args;
+ return 1;
+
+out_update_drop:
+ dprintk("nfsd: Dropping request; may be revisited later\n");
+ nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
+out_dropit:
+ return 0;
+
+out_encode_err:
+ dprintk("nfsd: failed to encode result!\n");
+ nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
+ *statp = rpc_system_err;
return 1;
}
next prev parent reply other threads:[~2020-09-29 14:04 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-29 14:03 [PATCH v2 00/11] nfsd_dispatch() clean up Chuck Lever
2020-09-29 14:03 ` [PATCH v2 01/11] nfsd: rq_lease_breaker cleanup Chuck Lever
2020-09-29 14:03 ` [PATCH v2 02/11] lockd: Replace PROC() macro with open code Chuck Lever
2020-09-29 14:03 ` [PATCH v2 03/11] NFSACL: " Chuck Lever
2020-09-29 14:03 ` [PATCH v2 04/11] NFSD: Encoder and decoder functions are always present Chuck Lever
2020-09-29 14:04 ` [PATCH v2 05/11] NFSD: Clean up switch statement in nfsd_dispatch() Chuck Lever
2020-09-29 14:04 ` [PATCH v2 06/11] NFSD: Clean up stale comments " Chuck Lever
2020-09-29 14:04 ` [PATCH v2 07/11] NFSD: Clean up nfsd_dispatch() variables Chuck Lever
2020-09-29 14:04 ` Chuck Lever [this message]
2020-09-29 14:04 ` [PATCH v2 09/11] NFSD: Set *statp in success path Chuck Lever
2020-09-29 14:04 ` [PATCH v2 10/11] NFSD: Fix .pc_release method for NFSv2 Chuck Lever
2020-09-29 14:04 ` [PATCH v2 11/11] NFSD: Call NFSv2 encoders on error returns Chuck Lever
2020-09-29 15:53 ` Chuck Lever
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