From patchwork Tue Mar 23 15:10:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 408711 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 5741FC433E4 for ; Tue, 23 Mar 2021 15:11:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 36D08619B9 for ; Tue, 23 Mar 2021 15:11:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232710AbhCWPKm (ORCPT ); Tue, 23 Mar 2021 11:10:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:41752 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232717AbhCWPKH (ORCPT ); Tue, 23 Mar 2021 11:10:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 84136619C4; Tue, 23 Mar 2021 15:10:06 +0000 (UTC) Subject: [PATCH 2/2] SUNRPC: Refresh rq_pages using a bulk page allocator From: Chuck Lever To: mgorman@techsingularity.net Cc: brouer@redhat.com, vbabka@suse.cz, akpm@linux-foundation.org, hch@infradead.org, alexander.duyck@gmail.com, willy@infradead.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org Date: Tue, 23 Mar 2021 11:10:05 -0400 Message-ID: <161651220579.3977.8959177746864957646.stgit@klimt.1015granger.net> In-Reply-To: <161650953543.3977.9991115610287676892.stgit@klimt.1015granger.net> References: <161650953543.3977.9991115610287676892.stgit@klimt.1015granger.net> User-Agent: StGit/1.0-5-g755c MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Reduce the rate at which nfsd threads hammer on the page allocator. This improves throughput scalability by enabling the threads to run more independently of each other. Signed-off-by: Chuck Lever --- net/sunrpc/svc_xprt.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 609bda97d4ae..d2792b2bf006 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -643,30 +643,31 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) { struct svc_serv *serv = rqstp->rq_server; struct xdr_buf *arg = &rqstp->rq_arg; - int pages; - int i; + unsigned long pages, filled; - /* now allocate needed pages. If we get a failure, sleep briefly */ pages = (serv->sv_max_mesg + 2 * PAGE_SIZE) >> PAGE_SHIFT; if (pages > RPCSVC_MAXPAGES) { - pr_warn_once("svc: warning: pages=%u > RPCSVC_MAXPAGES=%lu\n", + pr_warn_once("svc: warning: pages=%lu > RPCSVC_MAXPAGES=%lu\n", pages, RPCSVC_MAXPAGES); /* use as many pages as possible */ pages = RPCSVC_MAXPAGES; } - for (i = 0; i < pages ; i++) - while (rqstp->rq_pages[i] == NULL) { - struct page *p = alloc_page(GFP_KERNEL); - if (!p) { - set_current_state(TASK_INTERRUPTIBLE); - if (signalled() || kthread_should_stop()) { - set_current_state(TASK_RUNNING); - return -EINTR; - } - schedule_timeout(msecs_to_jiffies(500)); - } - rqstp->rq_pages[i] = p; + + for (;;) { + filled = alloc_pages_bulk_array(GFP_KERNEL, pages, + rqstp->rq_pages); + /* We assume that if the next array element is populated, + * all the following elements are as well, thus we're done. */ + if (filled == pages || rqstp->rq_pages[filled]) + break; + + set_current_state(TASK_INTERRUPTIBLE); + if (signalled() || kthread_should_stop()) { + set_current_state(TASK_RUNNING); + return -EINTR; } + schedule_timeout(msecs_to_jiffies(500)); + } rqstp->rq_page_end = &rqstp->rq_pages[pages]; rqstp->rq_pages[pages] = NULL; /* this might be seen in nfsd_splice_actor() */