[PATCH v12 2/5] netfs, cachefiles: Add a couple of traces for write failure

[David Howells <dhowells@redhat.com>]

Add a couple of subrequest traces for write failure in the cache.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Paulo Alcantara <pc@manguebit.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
---
 fs/cachefiles/io.c           | 8 ++++++--
 include/trace/events/netfs.h | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index 2c1cd703f4bf..dac48fdf85d1 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -605,10 +605,14 @@ static void cachefiles_prepare_write_subreq(struct netfs_io_subrequest *subreq)
 	stream->sreq_max_segs = BIO_MAX_VECS;
 
 	if (!cachefiles_cres_file(cres)) {
-		if (!fscache_wait_for_operation(cres, FSCACHE_WANT_WRITE))
+		if (!fscache_wait_for_operation(cres, FSCACHE_WANT_WRITE)) {
+			trace_netfs_sreq(subreq, netfs_sreq_trace_cache_waitfail);
 			return netfs_prepare_write_failed(subreq);
-		if (!cachefiles_cres_file(cres))
+		}
+		if (!cachefiles_cres_file(cres)) {
+			trace_netfs_sreq(subreq, netfs_sreq_trace_cache_nofile);
 			return netfs_prepare_write_failed(subreq);
+		}
 	}
 }
 
diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h
index 303309be253f..35826aea1c2d 100644
--- a/include/trace/events/netfs.h
+++ b/include/trace/events/netfs.h
@@ -93,8 +93,10 @@
 	EM(netfs_sreq_trace_abandoned,		"ABNDN")	\
 	EM(netfs_sreq_trace_add_donations,	"+DON ")	\
 	EM(netfs_sreq_trace_added,		"ADD  ")	\
+	EM(netfs_sreq_trace_cache_nofile,	"CA-!F")	\
 	EM(netfs_sreq_trace_cache_nowrite,	"CA-NW")	\
 	EM(netfs_sreq_trace_cache_prepare,	"CA-PR")	\
+	EM(netfs_sreq_trace_cache_waitfail,	"CA-!W")	\
 	EM(netfs_sreq_trace_cache_write,	"CA-WR")	\
 	EM(netfs_sreq_trace_cancel,		"CANCL")	\
 	EM(netfs_sreq_trace_clear,		"CLEAR")	\