From: Huang Ying <ying.hu...@intel.com> It's hard to write a whole transparent huge page (THP) to a file backed swap device during swapping out and the file backed swap device isn't very popular. So the huge cluster allocation for the file backed swap device is disabled.
Signed-off-by: "Huang, Ying" <ying.hu...@intel.com> Cc: Johannes Weiner <han...@cmpxchg.org> Cc: Minchan Kim <minc...@kernel.org> Cc: Hugh Dickins <hu...@google.com> Cc: Shaohua Li <s...@kernel.org> Cc: Rik van Riel <r...@redhat.com> --- mm/swapfile.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index bd0f38f31d3d..2a2f5d08f0a9 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -947,9 +947,10 @@ int get_swap_pages(int n_goal, bool cluster, swp_entry_t swp_entries[]) spin_unlock(&si->lock); goto nextsi; } - if (cluster) - n_ret = swap_alloc_cluster(si, swp_entries); - else + if (cluster) { + if (!(si->flags & SWP_FILE)) + n_ret = swap_alloc_cluster(si, swp_entries); + } else n_ret = scan_swap_map_slots(si, SWAP_HAS_CACHE, n_goal, swp_entries); spin_unlock(&si->lock); -- 2.11.0