From: Mikulas Patocka <mpatocka@xxxxxxxxxx> Subject: mm: add cond_resched() to generic_swapfile_activate() generic_swapfile_activate() can take quite long time, it iterates over all blocks of a file, so add cond_resched to it. I observed about 1 second stalls when activating a swapfile that was almost unfragmented - this patch fixes it. Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1607221710580.4818@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_io.c | 2 ++ 1 file changed, 2 insertions(+) diff -puN mm/page_io.c~mm-add-cond_resched-to-generic_swapfile_activate mm/page_io.c --- a/mm/page_io.c~mm-add-cond_resched-to-generic_swapfile_activate +++ a/mm/page_io.c @@ -166,6 +166,8 @@ int generic_swapfile_activate(struct swa unsigned block_in_page; sector_t first_block; + cond_resched(); + first_block = bmap(inode, probe_block); if (first_block == 0) goto bad_bmap; _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
