From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Rientjes , Mel Gorman , Rik van Riel , Vlastimil Babka , Joonsoo Kim , Andrew Morton , Linus Torvalds Subject: [PATCH 3.14 28/37] mm, compaction: determine isolation mode only once Date: Tue, 7 Oct 2014 16:19:45 -0700 Message-Id: <20141007231827.921630538@linuxfoundation.org> In-Reply-To: <20141007231827.043235686@linuxfoundation.org> References: <20141007231827.043235686@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Rientjes commit da1c67a76f7cf2b3404823d24f9f10fa91aa5dc5 upstream. The conditions that control the isolation mode in isolate_migratepages_range() do not change during the iteration, so extract them out and only define the value once. This actually does have an effect, gcc doesn't optimize it itself because of cc->sync. Signed-off-by: David Rientjes Cc: Mel Gorman Acked-by: Rik van Riel Acked-by: Vlastimil Babka Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman --- mm/compaction.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) --- a/mm/compaction.c +++ b/mm/compaction.c @@ -460,12 +460,13 @@ isolate_migratepages_range(struct zone * unsigned long last_pageblock_nr = 0, pageblock_nr; unsigned long nr_scanned = 0, nr_isolated = 0; struct list_head *migratelist = &cc->migratepages; - isolate_mode_t mode = 0; struct lruvec *lruvec; unsigned long flags; bool locked = false; struct page *page = NULL, *valid_page = NULL; bool skipped_async_unsuitable = false; + const isolate_mode_t mode = (!cc->sync ? ISOLATE_ASYNC_MIGRATE : 0) | + (unevictable ? ISOLATE_UNEVICTABLE : 0); /* * Ensure that there are not too many pages isolated from the LRU @@ -608,12 +609,6 @@ isolate_migratepages_range(struct zone * continue; } - if (!cc->sync) - mode |= ISOLATE_ASYNC_MIGRATE; - - if (unevictable) - mode |= ISOLATE_UNEVICTABLE; - lruvec = mem_cgroup_page_lruvec(page, zone); /* Try isolate the page */