diff options
| -rw-r--r-- | fs/nfsd/nfssvc.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index b8e8d80e984c..a8ea4dbfa56b 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -966,6 +966,20 @@ nfsd(void *vrqstp) return 0; } +/* + * Set rq_status_counter back to an even value, indicating that the rqstp + * fields are no longer meaningful to a lockless reader. This pairs with the + * odd-valued store made once the request has been decoded, and must run on + * every return path that follows it so that the seq-lock like protocol used + * by nfsd_nl_rpc_status_get_dumpit() is not left permanently odd. The store + * also advances the counter so a concurrent reader detects the transition. + */ +static void nfsd_status_counter_set_idle(struct svc_rqst *rqstp) +{ + smp_store_release(&rqstp->rq_status_counter, + (rqstp->rq_status_counter | 1) + 1); +} + /** * nfsd_dispatch - Process an NFS or NFSACL or LOCALIO Request * @rqstp: incoming request @@ -1028,14 +1042,9 @@ int nfsd_dispatch(struct svc_rqst *rqstp) if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream)) goto out_encode_err; - /* - * Release rq_status_counter setting it to an even value after the rpc - * request has been properly processed. - */ - smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter + 1); - nfsd_cache_update(rqstp, rp, ntli->ntli_cachetype, nfs_reply); out_cached_reply: + nfsd_status_counter_set_idle(rqstp); return 1; out_decode_err: @@ -1046,12 +1055,14 @@ out_decode_err: out_update_drop: nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); out_dropit: + nfsd_status_counter_set_idle(rqstp); return 0; out_encode_err: trace_nfsd_cant_encode_err(rqstp); nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); *statp = rpc_system_err; + nfsd_status_counter_set_idle(rqstp); return 1; } |