From patchwork Thu Feb 27 21:11:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Simmons X-Patchwork-Id: 11410029 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AC147138D for ; Thu, 27 Feb 2020 21:28:17 +0000 (UTC) Received: from pdx1-mailman02.dreamhost.com (pdx1-mailman02.dreamhost.com [64.90.62.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 949D7246A0 for ; Thu, 27 Feb 2020 21:28:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 949D7246A0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lustre-devel-bounces@lists.lustre.org Received: from pdx1-mailman02.dreamhost.com (localhost [IPv6:::1]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id 14BCA3492CC; Thu, 27 Feb 2020 13:24:44 -0800 (PST) X-Original-To: lustre-devel@lists.lustre.org Delivered-To: lustre-devel-lustre.org@pdx1-mailman02.dreamhost.com Received: from smtp3.ccs.ornl.gov (smtp3.ccs.ornl.gov [160.91.203.39]) by pdx1-mailman02.dreamhost.com (Postfix) with ESMTP id D6B8021FCB4 for ; Thu, 27 Feb 2020 13:19:23 -0800 (PST) Received: from star.ccs.ornl.gov (star.ccs.ornl.gov [160.91.202.134]) by smtp3.ccs.ornl.gov (Postfix) with ESMTP id D04602AF2; Thu, 27 Feb 2020 16:18:15 -0500 (EST) Received: by star.ccs.ornl.gov (Postfix, from userid 2004) id CEAC346F; Thu, 27 Feb 2020 16:18:15 -0500 (EST) From: James Simmons To: Andreas Dilger , Oleg Drokin , NeilBrown Date: Thu, 27 Feb 2020 16:11:23 -0500 Message-Id: <1582838290-17243-216-git-send-email-jsimmons@infradead.org> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Subject: [lustre-devel] [PATCH 215/622] lustre: osc: reduce atomic ops in osc_enter_cache_try X-BeenThere: lustre-devel@lists.lustre.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "For discussing Lustre software development." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Li Dongyang , Lustre Development List MIME-Version: 1.0 Errors-To: lustre-devel-bounces@lists.lustre.org Sender: "lustre-devel" From: Li Dongyang We can reduce the number of atomic ops performed on obd_dirty_pages for the common case. WC-bug-id: https://jira.whamcloud.com/browse/LU-11775 Lustre-commit: 8b364fbd6bd9 ("LU-11775 osc: reduce atomic ops in osc_enter_cache_try") Signed-off-by: Li Dongyang Reviewed-on: https://review.whamcloud.com/33859 Reviewed-by: Patrick Farrell Reviewed-by: Alexey Lyashkov Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- fs/lustre/osc/osc_cache.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/fs/lustre/osc/osc_cache.c b/fs/lustre/osc/osc_cache.c index a18e791..bdaf65f 100644 --- a/fs/lustre/osc/osc_cache.c +++ b/fs/lustre/osc/osc_cache.c @@ -1423,7 +1423,6 @@ static void osc_consume_write_grant(struct client_obd *cli, { assert_spin_locked(&cli->cl_loi_list_lock); LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT)); - atomic_long_inc(&obd_dirty_pages); cli->cl_dirty_pages++; pga->flag |= OBD_BRW_FROM_GRANT; CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n", @@ -1560,13 +1559,18 @@ static bool osc_enter_cache_try(struct client_obd *cli, if (osc_reserve_grant(cli, bytes) < 0) return rc; - if (cli->cl_dirty_pages < cli->cl_dirty_max_pages && - atomic_long_read(&obd_dirty_pages) + 1 <= obd_max_dirty_pages) { - osc_consume_write_grant(cli, &oap->oap_brw_page); - rc = true; - } else { - __osc_unreserve_grant(cli, bytes, bytes); + if (cli->cl_dirty_pages < cli->cl_dirty_max_pages) { + if (atomic_long_add_return(1, &obd_dirty_pages) <= + obd_max_dirty_pages) { + osc_consume_write_grant(cli, &oap->oap_brw_page); + rc = true; + goto out; + } else + atomic_long_dec(&obd_dirty_pages); } + __osc_unreserve_grant(cli, bytes, bytes); + +out: return rc; }