diff mbox series

[v2,3/4] fs: use fput_close() in filp_close()

Message ID 20250304183506.498724-4-mjguzik@gmail.com (mailing list archive)
State New
Headers show
Series avoid the extra atomic on a ref when closing a fd | expand

Commit Message

Mateusz Guzik March 4, 2025, 6:35 p.m. UTC 
When tracing a kernel build over refcounts seen this is a wash:
@[kprobe:filp_close]:
[0]                32195 |@@@@@@@@@@                                          |
[1]               164567 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|

I verified vast majority of the skew comes from do_close_on_exec() which
could be changed to use a different variant instead.

Even without changing that, the 19.5% of calls which got here still can
save the extra atomic. Calls here are borderline non-existent compared
to fput (over 3.2 mln!), so they should not negatively affect
scalability.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
---
 fs/open.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/open.c b/fs/open.c
index fc1c6118eb30..ffb7e2e5e1ef 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -1589,7 +1589,7 @@  int filp_close(struct file *filp, fl_owner_t id)
 	int retval;
 
 	retval = filp_flush(filp, id);
-	fput(filp);
+	fput_close(filp);
 
 	return retval;
 }