[PATCH 2/2] fuse: Replace page without copying in fuse_writepage_in_flight()

From: Kirill Tkhai
Date: Mon Nov 26 2018 - 04:46:26 EST


It looks like we can optimize old_req page replacement
and avoid copying by simple updating the request's page.

Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
---
fs/fuse/file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index c6650c68b31a..83b54b082c86 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1778,7 +1778,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req,
if (old_req->num_pages == 1 && old_req != first_req) {
struct backing_dev_info *bdi = inode_to_bdi(page->mapping->host);

- copy_highpage(old_req->pages[0], page);
+ swap(old_req->pages[0], page);
spin_unlock(&fc->lock);

dec_wb_stat(&bdi->wb, WB_WRITEBACK);