From 75acacb6583df0b9328dc701d8eeea05af49b8b5 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 28 Dec 2021 14:27:56 -0500 Subject: NFSD: Trace boot verifier resets According to commit bbf2f098838a ("nfsd: Reset the boot verifier on all write I/O errors"), the Linux NFS server forces all clients to resend pending unstable writes if any server-side write or commit operation encounters an error (say, ENOSPC). This is a rare and quite exceptional event that could require administrative recovery action, so it should be made trace-able. Example trace event: nfsd-938 [002] 7174.945558: nfsd_writeverf_reset: boot_time= 61cc920d xid=0xdcd62036 error=-28 new verifier=0x08aecc6142515904 Signed-off-by: Chuck Lever --- fs/nfsd/trace.h | 28 ++++++++++++++++++++++++++++ fs/nfsd/vfs.c | 13 ++++++++++--- 2 files changed, 38 insertions(+), 3 deletions(-) (limited to 'fs/nfsd') diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index a0b2b8d87de6..c4cf56327843 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -574,6 +574,34 @@ DEFINE_EVENT(nfsd_net_class, nfsd_##name, \ DEFINE_NET_EVENT(grace_start); DEFINE_NET_EVENT(grace_complete); +TRACE_EVENT(nfsd_writeverf_reset, + TP_PROTO( + const struct nfsd_net *nn, + const struct svc_rqst *rqstp, + int error + ), + TP_ARGS(nn, rqstp, error), + TP_STRUCT__entry( + __field(unsigned long long, boot_time) + __field(u32, xid) + __field(int, error) + __array(unsigned char, verifier, NFS4_VERIFIER_SIZE) + ), + TP_fast_assign( + __entry->boot_time = nn->boot_time; + __entry->xid = be32_to_cpu(rqstp->rq_xid); + __entry->error = error; + + /* avoid seqlock inside TP_fast_assign */ + memcpy(__entry->verifier, nn->writeverf, + NFS4_VERIFIER_SIZE); + ), + TP_printk("boot_time=%16llx xid=0x%08x error=%d new verifier=0x%s", + __entry->boot_time, __entry->xid, __entry->error, + __print_hex_str(__entry->verifier, NFS4_VERIFIER_SIZE) + ) +); + TRACE_EVENT(nfsd_clid_cred_mismatch, TP_PROTO( const struct nfs4_client *clp, diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 49564457bd3d..e4e59e1660e1 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -553,14 +553,17 @@ __be32 nfsd4_clone_file_range(struct svc_rqst *rqstp, if (!status) status = commit_inode_metadata(file_inode(src)); if (status < 0) { + struct nfsd_net *nn = net_generic(nf_dst->nf_net, + nfsd_net_id); + trace_nfsd_clone_file_range_err(rqstp, &nfsd4_get_cstate(rqstp)->save_fh, src_pos, &nfsd4_get_cstate(rqstp)->current_fh, dst_pos, count, status); - nfsd_reset_write_verifier(net_generic(nf_dst->nf_net, - nfsd_net_id)); + nfsd_reset_write_verifier(nn); + trace_nfsd_writeverf_reset(nn, rqstp, status); ret = nfserrno(status); } } @@ -1017,6 +1020,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, host_err = vfs_iter_write(file, &iter, &pos, flags); if (host_err < 0) { nfsd_reset_write_verifier(nn); + trace_nfsd_writeverf_reset(nn, rqstp, host_err); goto out_nfserr; } *cnt = host_err; @@ -1028,8 +1032,10 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, if (stable && use_wgather) { host_err = wait_for_concurrent_writes(file); - if (host_err < 0) + if (host_err < 0) { nfsd_reset_write_verifier(nn); + trace_nfsd_writeverf_reset(nn, rqstp, host_err); + } } out_nfserr: @@ -1151,6 +1157,7 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, break; default: nfsd_reset_write_verifier(nn); + trace_nfsd_writeverf_reset(nn, rqstp, err2); } err = nfserrno(err2); } else -- cgit v1.2.3