[PATCH] splice: call handle_ra_miss() on failure to lookup page

Notify the readahead logic of the missing page. Suggested by
Oleg Nesterov.

Signed-off-by: Jens Axboe <axboe@suse.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/splice.c b/fs/splice.c
index d7538d83c367..0a6916423e7d 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -302,6 +302,12 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
                 page = find_get_page(mapping, index);
                 if (!page) {
                         /*
+                         * Make sure the read-ahead engine is notified
+                         * about this failure.
+                         */
+                        handle_ra_miss(mapping, &in->f_ra, index);
+
+                        /*
                          * page didn't exist, allocate one.
                          */
                         page = page_cache_alloc_cold(mapping);