From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29F04C55185 for ; Wed, 22 Apr 2020 15:04:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 060FC215A4 for ; Wed, 22 Apr 2020 15:04:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728370AbgDVPEE (ORCPT ); Wed, 22 Apr 2020 11:04:04 -0400 Received: from mx2.suse.de ([195.135.220.15]:58114 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728072AbgDVPDH (ORCPT ); Wed, 22 Apr 2020 11:03:07 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 5EB3FADEB; Wed, 22 Apr 2020 15:03:03 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 928911E0E6E; Wed, 22 Apr 2020 17:03:03 +0200 (CEST) From: Jan Kara To: Matthew Wilcox Cc: , LKML , Jan Kara Subject: [PATCH 14/23] workingset: Use xas_store_noinit() to clear shadow entry Date: Wed, 22 Apr 2020 17:02:47 +0200 Message-Id: <20200422150256.23473-15-jack@suse.cz> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200422150256.23473-1-jack@suse.cz> References: <20200422150256.23473-1-jack@suse.cz> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Shadow entries have no marks. Use xas_store_noinit() to clear the entry so avoid unneeded initialization of the xarray marks. This provides a nice boost to truncate numbers. Sample benchmark showing time to truncate 128 files 1GB each on machine with 64GB of RAM (so about half of entries are shadow entries): AVG STDDEV Vanilla 4.825s 0.036 Patched 4.516s 0.014 So we can see about 6% reduction in overall truncate time. Signed-off-by: Jan Kara --- mm/truncate.c | 2 +- mm/workingset.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/truncate.c b/mm/truncate.c index dd9ebc1da356..baef636564cc 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -39,7 +39,7 @@ static inline void __clear_shadow_entry(struct address_space *mapping, xas_set_update(&xas, workingset_update_node); if (xas_load(&xas) != entry) return; - xas_store(&xas, NULL); + xas_store_noinit(&xas, NULL); mapping->nrexceptional--; } diff --git a/mm/workingset.c b/mm/workingset.c index 474186b76ced..6a492140057f 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -537,7 +537,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, * We could store a shadow entry here which was the minimum of the * shadow entries we were tracking ... */ - xas_store(&xas, NULL); + xas_store_noinit(&xas, NULL); __inc_lruvec_slab_state(node, WORKINGSET_NODERECLAIM); out_invalid: -- 2.16.4