nfsd: Add I/O trace points in the NFSv4 read proc

NFSv4 read compound processing invokes nfsd_splice_read and
nfs_readv directly, so the trace points currently in nfsd_read are
not invoked for NFSv4 reads.

Move the NFSD READ trace points to common helpers so that NFSv4
reads are captured.

Also, record any local I/O error that occurs, the total count of
bytes that were actually returned, and whether splice or vectored
read was used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index b773b31..250e0c5 100644 (file)
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -751,6 +751,9 @@ nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
        if (read->rd_offset >= OFFSET_MAX)
                return nfserr_inval;
 
+       trace_nfsd_read_start(rqstp, &cstate->current_fh,
+                             read->rd_offset, read->rd_length);
+
        /*
         * If we do a zero copy read, then a client will see read data
         * that reflects the state of the file *after* performing the
@@ -783,6 +786,8 @@ nfsd4_read_release(union nfsd4_op_u *u)
 {
        if (u->read.rd_filp)
                fput(u->read.rd_filp);
+       trace_nfsd_read_done(u->read.rd_rqstp, u->read.rd_fhp,
+                            u->read.rd_offset, u->read.rd_length);
 }
 
 static __be32

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 9f8ef2c..dd72cdf 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3427,8 +3427,9 @@ static __be32 nfsd4_encode_splice_read(
                return nfserr_resource;
 
        len = maxcount;
-       nfserr = nfsd_splice_read(read->rd_rqstp, file,
-                                 read->rd_offset, &maxcount);
+       nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
+                                 file, read->rd_offset, &maxcount);
+       read->rd_length = maxcount;
        if (nfserr) {
                /*
                 * nfsd_splice_actor may have already messed with the
@@ -3511,8 +3512,9 @@ static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
        read->rd_vlen = v;
 
        len = maxcount;
-       nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
-                       read->rd_vlen, &maxcount);
+       nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
+                           resp->rqstp->rq_vec, read->rd_vlen, &maxcount);
+       read->rd_length = maxcount;
        if (nfserr)
                return nfserr;
        xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 653e9ee..a8bbd9d 100644 (file)
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -43,7 +43,8 @@ DEFINE_EVENT(nfsd_io_class, nfsd_##name,      \
        TP_ARGS(rqstp, fhp, offset, len))
 
 DEFINE_NFSD_IO_EVENT(read_start);
-DEFINE_NFSD_IO_EVENT(read_opened);
+DEFINE_NFSD_IO_EVENT(read_splice);
+DEFINE_NFSD_IO_EVENT(read_vector);
 DEFINE_NFSD_IO_EVENT(read_io_done);
 DEFINE_NFSD_IO_EVENT(read_done);
 DEFINE_NFSD_IO_EVENT(write_start);
@@ -82,6 +83,7 @@ DEFINE_EVENT(nfsd_err_class, nfsd_##name,     \
                 int            len),           \
        TP_ARGS(rqstp, fhp, offset, len))
 
+DEFINE_NFSD_ERR_EVENT(read_err);
 DEFINE_NFSD_ERR_EVENT(write_err);
 
 #include "state.h"

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index ee59a0b..2410b09 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -881,20 +881,24 @@ static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
        return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
 }
 
-static __be32
-nfsd_finish_read(struct file *file, unsigned long *count, int host_err)
+static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                              struct file *file, loff_t offset,
+                              unsigned long *count, int host_err)
 {
        if (host_err >= 0) {
                nfsdstats.io_read += host_err;
                *count = host_err;
                fsnotify_access(file);
+               trace_nfsd_read_io_done(rqstp, fhp, offset, *count);
                return 0;
-       } else 
+       } else {
+               trace_nfsd_read_err(rqstp, fhp, offset, host_err);
                return nfserrno(host_err);
+       }
 }
 
-__be32 nfsd_splice_read(struct svc_rqst *rqstp,
-                    struct file *file, loff_t offset, unsigned long *count)
+__be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                       struct file *file, loff_t offset, unsigned long *count)
 {
        struct splice_desc sd = {
                .len            = 0,
@@ -904,21 +908,23 @@ __be32 nfsd_splice_read(struct svc_rqst *rqstp,
        };
        int host_err;
 
+       trace_nfsd_read_splice(rqstp, fhp, offset, *count);
        rqstp->rq_next_page = rqstp->rq_respages + 1;
        host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
-       return nfsd_finish_read(file, count, host_err);
+       return nfsd_finish_read(rqstp, fhp, file, offset, count, host_err);
 }
 
-__be32 nfsd_readv(struct file *file, loff_t offset, struct kvec *vec, int vlen,
-               unsigned long *count)
+__be32 nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                 struct file *file, loff_t offset,
+                 struct kvec *vec, int vlen, unsigned long *count)
 {
        struct iov_iter iter;
        int host_err;
 
+       trace_nfsd_read_vector(rqstp, fhp, offset, *count);
        iov_iter_kvec(&iter, READ | ITER_KVEC, vec, vlen, *count);
        host_err = vfs_iter_read(file, &iter, &offset, 0);
-
-       return nfsd_finish_read(file, count, host_err);
+       return nfsd_finish_read(rqstp, fhp, file, offset, count, host_err);
 }
 
 /*
@@ -1034,14 +1040,10 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 
        ra = nfsd_init_raparms(file);
 
-       trace_nfsd_read_opened(rqstp, fhp, offset, *count);
-
        if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &rqstp->rq_flags))
-               err = nfsd_splice_read(rqstp, file, offset, count);
+               err = nfsd_splice_read(rqstp, fhp, file, offset, count);
        else
-               err = nfsd_readv(file, offset, vec, vlen, count);
-
-       trace_nfsd_read_io_done(rqstp, fhp, offset, *count);
+               err = nfsd_readv(rqstp, fhp, file, offset, vec, vlen, count);
 
        if (ra)
                nfsd_put_raparams(file, ra);

diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index be6d8e0..a7e1073 100644 (file)
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -78,10 +78,13 @@ __be32              nfsd_commit(struct svc_rqst *, struct svc_fh *,
 __be32         nfsd_open(struct svc_rqst *, struct svc_fh *, umode_t,
                                int, struct file **);
 struct raparms;
-__be32         nfsd_splice_read(struct svc_rqst *,
-                               struct file *, loff_t, unsigned long *);
-__be32         nfsd_readv(struct file *, loff_t, struct kvec *, int,
-                               unsigned long *);
+__be32         nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                               struct file *file, loff_t offset,
+                               unsigned long *count);
+__be32         nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                               struct file *file, loff_t offset,
+                               struct kvec *vec, int vlen,
+                               unsigned long *count);
 __be32                 nfsd_read(struct svc_rqst *, struct svc_fh *,
                                loff_t, struct kvec *, int, unsigned long *);
 __be32                 nfsd_write(struct svc_rqst *, struct svc_fh *, loff_t,