nfsd: Add I/O trace points in the NFSv4 write path

NFSv4 write compound processing invokes nfsd_vfs_write directly. The
trace points currently in nfsd_write are not effective for NFSv4
writes.

Move the trace points into the shared nfsd_vfs_write() helper.

After the I/O, we also want to record any local I/O error that
might have occurred, and the total count of bytes that were actually
moved (rather than the requested number).

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

1 files changed, 33 insertions, 0 deletions

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 30e04852a4e0..653e9ee754d2 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -51,6 +51,39 @@ DEFINE_NFSD_IO_EVENT(write_opened);
 DEFINE_NFSD_IO_EVENT(write_io_done);
 DEFINE_NFSD_IO_EVENT(write_done);
 
+DECLARE_EVENT_CLASS(nfsd_err_class,
+        TP_PROTO(struct svc_rqst *rqstp,
+                 struct svc_fh  *fhp,
+                 loff_t         offset,
+                 int            status),
+        TP_ARGS(rqstp, fhp, offset, status),
+        TP_STRUCT__entry(
+                __field(u32, xid)
+                __field(u32, fh_hash)
+                __field(loff_t, offset)
+                __field(int, status)
+        ),
+        TP_fast_assign(
+                __entry->xid = be32_to_cpu(rqstp->rq_xid);
+                __entry->fh_hash = knfsd_fh_hash(&fhp->fh_handle);
+                __entry->offset = offset;
+                __entry->status = status;
+        ),
+        TP_printk("xid=0x%08x fh_hash=0x%08x offset=%lld status=%d",
+                  __entry->xid, __entry->fh_hash,
+                  __entry->offset, __entry->status)
+)
+
+#define DEFINE_NFSD_ERR_EVENT(name)             \
+DEFINE_EVENT(nfsd_err_class, nfsd_##name,       \
+        TP_PROTO(struct svc_rqst *rqstp,        \
+                 struct svc_fh  *fhp,           \
+                 loff_t         offset,         \
+                 int            len),           \
+        TP_ARGS(rqstp, fhp, offset, len))
+
+DEFINE_NFSD_ERR_EVENT(write_err);
+
 #include "state.h"
 
 DECLARE_EVENT_CLASS(nfsd_stateid_class,