diff mbox series

[v2,1/3] mm: check compound_head(page)->mapping in filemap_fault()

Message ID 20190614182204.2673660-2-songliubraving@fb.com (mailing list archive)
State New, archived
Headers show
Series Enable THP for text section of non-shmem files | expand

Commit Message

Song Liu June 14, 2019, 6:22 p.m. UTC 
Currently, filemap_fault() avoids trace condition with truncate by
checking page->mapping == mapping. This does not work for compound
pages. This patch let it check compound_head(page)->mapping instead.

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 mm/filemap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Rik van Riel June 17, 2019, 2:59 p.m. UTC | #1 
On Fri, 2019-06-14 at 11:22 -0700, Song Liu wrote:
> Currently, filemap_fault() avoids trace condition with truncate by
> checking page->mapping == mapping. This does not work for compound
> pages. This patch let it check compound_head(page)->mapping instead.
> 
> Signed-off-by: Song Liu <songliubraving@fb.com>

Acked-by: Rik van Riel <riel@surriel.com>
diff mbox series

Patch

diff --git a/mm/filemap.c b/mm/filemap.c
index df2006ba0cfa..f5b79a43946d 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2517,7 +2517,7 @@  vm_fault_t filemap_fault(struct vm_fault *vmf)
 		goto out_retry;
 
 	/* Did it get truncated? */
-	if (unlikely(page->mapping != mapping)) {
+	if (unlikely(compound_head(page)->mapping != mapping)) {
 		unlock_page(page);
 		put_page(page);
 		goto retry_find;