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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46934C76195 for ; Wed, 15 Mar 2023 05:15:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231502AbjCOFPn (ORCPT ); Wed, 15 Mar 2023 01:15:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231338AbjCOFPJ (ORCPT ); Wed, 15 Mar 2023 01:15:09 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D740301AB; Tue, 14 Mar 2023 22:14:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=ZB/nojsqXTtfSMaj4C8ZgsYbK0b2FnBz3f1ii2GaXkQ=; b=hY0UUqTGJDzLw4RBYtIYxgeVvN 63iW/9r3FQoz3cmvNkkqfiUK9D3PXsg4xMaIMPfprUGUdDWLfFX8lqQ3C82dUtIIJbUVjiPS7bkew 3SVH8K0ra3lSNQjOGGGVyPINBnyh+l1lpy9vvC+bXrgxroKRo6SBBqMHZ/6OCUELUKsVgdksovkJT OvXxNguIF8woiUKmuJj3JF3fXhM+G7vSEr0sxyhz6N12DAq6wpZJTX8hDZKK1dlve+VZatmATm7Qi Cujmwp3ehFlZS15JwLjFg7ZbiZQcI3M7wVp8XqdQrQfxLY2iEj5jOexlolxHUH/oEfQmY/I+3E1Oo YD831Jww==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pcJTO-00DYEB-U2; Wed, 15 Mar 2023 05:14:50 +0000 From: "Matthew Wilcox (Oracle)" To: linux-arch@vger.kernel.org Cc: Yin Fengwei , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Matthew Wilcox Subject: [PATCH v4 36/36] filemap: Batch PTE mappings Date: Wed, 15 Mar 2023 05:14:44 +0000 Message-Id: <20230315051444.3229621-37-willy@infradead.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20230315051444.3229621-1-willy@infradead.org> References: <20230315051444.3229621-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org From: Yin Fengwei Call set_pte_range() once per contiguous range of the folio instead of once per page. This batches the updates to mm counters and the rmap. With a will-it-scale.page_fault3 like app (change file write fault testing to read fault testing. Trying to upstream it to will-it-scale at [1]) got 15% performance gain on a 48C/96T Cascade Lake test box with 96 processes running against xfs. Perf data collected before/after the change: 18.73%--page_add_file_rmap | --11.60%--__mod_lruvec_page_state | |--7.40%--__mod_memcg_lruvec_state | | | --5.58%--cgroup_rstat_updated | --2.53%--__mod_lruvec_state | --1.48%--__mod_node_page_state 9.93%--page_add_file_rmap_range | --2.67%--__mod_lruvec_page_state | |--1.95%--__mod_memcg_lruvec_state | | | --1.57%--cgroup_rstat_updated | --0.61%--__mod_lruvec_state | --0.54%--__mod_node_page_state The running time of __mode_lruvec_page_state() is reduced about 9%. [1]: https://github.com/antonblanchard/will-it-scale/pull/37 Signed-off-by: Yin Fengwei Signed-off-by: Matthew Wilcox (Oracle) --- mm/filemap.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index e2317623dcbf..7a1534460b55 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3483,11 +3483,12 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, struct file *file = vma->vm_file; struct page *page = folio_page(folio, start); unsigned int mmap_miss = READ_ONCE(file->f_ra.mmap_miss); - unsigned int ref_count = 0, count = 0; + unsigned int count = 0; + pte_t *old_ptep = vmf->pte; do { - if (PageHWPoison(page)) - continue; + if (PageHWPoison(page + count)) + goto skip; if (mmap_miss > 0) mmap_miss--; @@ -3497,20 +3498,33 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, * handled in the specific fault path, and it'll prohibit the * fault-around logic. */ - if (!pte_none(*vmf->pte)) - continue; + if (!pte_none(vmf->pte[count])) + goto skip; if (vmf->address == addr) ret = VM_FAULT_NOPAGE; - ref_count++; - set_pte_range(vmf, folio, page, 1, addr); - } while (vmf->pte++, page++, addr += PAGE_SIZE, ++count < nr_pages); + count++; + continue; +skip: + if (count) { + set_pte_range(vmf, folio, page, count, addr); + folio_ref_add(folio, count); + } - /* Restore the vmf->pte */ - vmf->pte -= nr_pages; + count++; + page += count; + vmf->pte += count; + addr += count * PAGE_SIZE; + count = 0; + } while (--nr_pages > 0); + + if (count) { + set_pte_range(vmf, folio, page, count, addr); + folio_ref_add(folio, count); + } - folio_ref_add(folio, ref_count); + vmf->pte = old_ptep; WRITE_ONCE(file->f_ra.mmap_miss, mmap_miss); return ret; -- 2.39.2