>From 3754c8617ef4377ce2ca2e3b28bdc28f8de1aa0d Mon Sep 17 00:00:00 2001 From: Jacobo Giralt <jacobo.giralt@xxxxxxxxx> Date: Sat, 5 Nov 2011 13:12:50 +0100 Subject: [PATCH] mm: migrate: One less atomic operation migrate_page_move_mapping drops a reference from the old page after unfreezing its counter. Both operations can be merged into a single atomic operation by directly unfreezing to one less reference. The same applies to migrate_huge_page_move_mapping. Signed-off-by: Jacobo Giralt <jacobo.giralt@xxxxxxxxx> --- mm/migrate.c | 10 ++++------ 1 files changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 33358f8..46d04a0 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -269,12 +269,12 @@ static int migrate_page_move_mapping(struct address_space *mapping, radix_tree_replace_slot(pslot, newpage); - page_unfreeze_refs(page, expected_count); /* - * Drop cache reference from old page. + * Drop cache reference from old page by unfreezing + * to one less reference. * We know this isn't the last reference. */ - __put_page(page); + page_unfreeze_refs(page, expected_count - 1); /* * If moved to a different zone then also account @@ -334,9 +334,7 @@ int migrate_huge_page_move_mapping(struct address_space *mapping, radix_tree_replace_slot(pslot, newpage); - page_unfreeze_refs(page, expected_count); - - __put_page(page); + page_unfreeze_refs(page, expected_count - 1); spin_unlock_irq(&mapping->tree_lock); return 0; -- 1.7.5.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>