[PATCH v5 15/32] cachefiles: Add some subrequest tracepoints

David Howells
2024-12-16T20:43:36Z

Add some tracepoints into the cachefiles write paths.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: netfs@lists.linux.dev
---
fs/cachefiles/io.c | 4 ++++
include/trace/events/netfs.h | 3 +++
2 files changed, 7 insertions(+)

diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index 6a821a959b59..92058ae43488 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -13,6 +13,7 @@
#include <linux/falloc.h>
#include <linux/sched/mm.h>
#include <trace/events/fscache.h>
+#include <trace/events/netfs.h>
#include "internal.h"

struct cachefiles_kiocb {
@@ -366,6 +367,7 @@ static int cachefiles_write(struct netfs_cache_resources *cres,
if (!fscache_wait_for_operation(cres, FSCACHE_WANT_WRITE)) {
if (term_func)
term_func(term_func_priv, -ENOBUFS, false);
+ trace_netfs_sreq(term_func_priv, netfs_sreq_trace_cache_nowrite);
return -ENOBUFS;
}

@@ -695,6 +697,7 @@ static void cachefiles_issue_write(struct netfs_io_subrequest *subreq)
iov_iter_truncate(&subreq->io_iter, len);
}

+ trace_netfs_sreq(subreq, netfs_sreq_trace_cache_prepare);
cachefiles_begin_secure(cache, &saved_cred);
ret = __cachefiles_prepare_write(object, cachefiles_cres_file(cres),
&start, &len, len, true);
@@ -704,6 +707,7 @@ static void cachefiles_issue_write(struct netfs_io_subrequest *subreq)
return;
}

+ trace_netfs_sreq(subreq, netfs_sreq_trace_cache_write);
cachefiles_write(&subreq->rreq->cache_resources,
subreq->start, &subreq->io_iter,
netfs_write_subrequest_terminated, subreq);
diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h
index 2dfc9f716e3b..02f6e179b7bc 100644
--- a/include/trace/events/netfs.h
+++ b/include/trace/events/netfs.h
@@ -74,6 +74,9 @@
#define netfs_sreq_traces \
EM(netfs_sreq_trace_add_donations, "+DON ") \
EM(netfs_sreq_trace_added, "ADD ") \
+ EM(netfs_sreq_trace_cache_nowrite, "CA-NW") \
+ EM(netfs_sreq_trace_cache_prepare, "CA-PR") \
+ EM(netfs_sreq_trace_cache_write, "CA-WR") \
EM(netfs_sreq_trace_clear, "CLEAR") \
EM(netfs_sreq_trace_discard, "DSCRD") \
EM(netfs_sreq_trace_donate_to_prev, "DON-P") \