From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759437AbcAUMJj (ORCPT ); Thu, 21 Jan 2016 07:09:39 -0500 Received: from mga09.intel.com ([134.134.136.24]:53324 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759255AbcAUMJf (ORCPT ); Thu, 21 Jan 2016 07:09:35 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,325,1449561600"; d="scan'208";a="898050999" From: "Kirill A. Shutemov" To: Andrew Morton , Andrea Arcangeli Cc: Hugh Dickins , Dave Hansen , Mel Gorman , Rik van Riel , Vlastimil Babka , Christoph Lameter , Naoya Horiguchi , Steve Capper , "Aneesh Kumar K.V" , Johannes Weiner , Michal Hocko , Jerome Marchand , Sasha Levin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCH 2/3] thp: change deferred_split_count() to return number of THP in queue Date: Thu, 21 Jan 2016 15:09:22 +0300 Message-Id: <1453378163-133609-3-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.7.0.rc3 In-Reply-To: <1453378163-133609-1-git-send-email-kirill.shutemov@linux.intel.com> References: <20160121012237.GE7119@redhat.com> <1453378163-133609-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I've got meaning of shrinker::count_objects() wrong: it should return number of potentially freeable objects, which is not necessary correlate with freeable memory. Returning 256 per THP in queue is not reasonable: shrinker::scan_objects() never called with nr_to_scan > 128 in my setup. Let's return 1 per THP and correct scan_object accordingly. Signed-off-by: Kirill A. Shutemov --- mm/huge_memory.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 769ea8db5771..36f98459f854 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3465,12 +3465,7 @@ static unsigned long deferred_split_count(struct shrinker *shrink, struct shrink_control *sc) { struct pglist_data *pgdata = NODE_DATA(sc->nid); - /* - * Split a page from split_queue will free up at least one page, - * at most HPAGE_PMD_NR - 1. We don't track exact number. - * Let's use HPAGE_PMD_NR / 2 as ballpark. - */ - return ACCESS_ONCE(pgdata->split_queue_len) * HPAGE_PMD_NR / 2; + return ACCESS_ONCE(pgdata->split_queue_len); } static unsigned long deferred_split_scan(struct shrinker *shrink, @@ -3511,7 +3506,7 @@ static unsigned long deferred_split_scan(struct shrinker *shrink, list_splice_tail(&list, &pgdata->split_queue); spin_unlock_irqrestore(&pgdata->split_queue_lock, flags); - return split * HPAGE_PMD_NR / 2; + return split; } static struct shrinker deferred_split_shrinker = { -- 2.7.0.rc3