From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: ARC-Seal: i=1; a=rsa-sha256; t=1522112542; cv=none; d=google.com; s=arc-20160816; b=IEYbkXA+iuWNQzQ1+kvtPG8Xcpm1qk3dF4Cj8Vv7f4f+ZOUHOI3FQmEWCM/RfHKrAR yU6BHRd6D2Ms0F2yNOTZmQekWK6r1xbiT9yzZlD9iqobPIABy8S+wTSAtwhw6jxleJG5 OK572uxwdDb6fQP/a+AwcAcKf4rRCy4HyRidm4Ulu86fIzW3MlqGq7VlgFoxHrkgXpZt XoTM7b0YAn2mc+hMs/1izxI4ApExK3kXo/uk8lH73EzSHxVKf3YRmUz/FomeCPGfHcG9 Z4v9DCN0CFfqiftbDi6tCgHxzwh+EdIJjN1D4O+jc0WEuEHrLmzeGLIgqgnsShbLtW6n MQRg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=roB/+tV1DQc6PSMvC+w0eQ6E80gqeu6ufz3YgWA2Xmw=; b=bFSxFf6zmhQ0CdOS+3AD/xCTUSKovHHH6o8t2apBYFnIKInjvfRXX0pARz+w3FuQjU GlgzvrFCMH4jbc+/3QG4Y1S2zNEmQNomtVduSHdhrHB8NXaQpObK9mN/Jc0Y4eUNiMAf J4EaYHnlA87KcoWFxtWBtk78dYHHpMtTRXiDPQwQoG0HdG6SdjCCVvnFqJxSe/WAeN2N VFncf1eBm4jibdVSctlUd5cjhxpSTRujUvR5OS9mJLnyS9+ofE98SntS6SgVe0mQ63st ktkvzTALQolMMzW2Y/taOM0UneDPWK6l86hPvvCmy/clU4V7PSMwzNMnWi2f3PftP6wb GYVw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=QqMDCm4g; spf=pass (google.com: domain of richard.weiyang@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=QqMDCm4g; spf=pass (google.com: domain of richard.weiyang@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com X-Google-Smtp-Source: AG47ELu7NARw4bm9Rmx7IgfvW3XriwomgnkM3PJWGdi9gbWlhUVlM5CD+CL18XQ8riuoQ0UNrxApCg== Date: Tue, 27 Mar 2018 09:02:13 +0800 From: Wei Yang To: Jia He Cc: Andrew Morton , Michal Hocko , Catalin Marinas , Mel Gorman , Will Deacon , Mark Rutland , Ard Biesheuvel , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Pavel Tatashin , Daniel Jordan , AKASHI Takahiro , Gioh Kim , Steven Sistare , Daniel Vacek , Eugeniu Rosca , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-mm@kvack.org, James Morse , Steve Capper , x86@kernel.org, Greg Kroah-Hartman , Kate Stewart , Philippe Ombredanne , Johannes Weiner , Kemi Wang , Petr Tesarik , YASUAKI ISHIMATSU , Andrey Ryabinin , Nikolay Borisov Subject: Re: [PATCH v3 0/5] optimize memblock_next_valid_pfn and early_pfn_valid Message-ID: <20180327010213.GA80447@WeideMacBook-Pro.local> Reply-To: Wei Yang References: <1522033340-6575-1-git-send-email-hejianet@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1522033340-6575-1-git-send-email-hejianet@gmail.com> User-Agent: Mutt/1.9.1 (2017-09-22) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1595967659920779416?= X-GMAIL-MSGID: =?utf-8?q?1596050681420848006?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Sun, Mar 25, 2018 at 08:02:14PM -0700, Jia He wrote: >Commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns >where possible") tried to optimize the loop in memmap_init_zone(). But >there is still some room for improvement. > >Patch 1 remain the memblock_next_valid_pfn when CONFIG_HAVE_ARCH_PFN_VALID > is enabled >Patch 2 optimizes the memblock_next_valid_pfn() >Patch 3~5 optimizes the early_pfn_valid(), I have to split it into parts > because the changes are located across subsystems. > >I tested the pfn loop process in memmap_init(), the same as before. >As for the performance improvement, after this set, I can see the time >overhead of memmap_init() is reduced from 41313 us to 24345 us in my >armv8a server(QDF2400 with 96G memory). > >Attached the memblock region information in my server. >[ 86.956758] Zone ranges: >[ 86.959452] DMA [mem 0x0000000000200000-0x00000000ffffffff] >[ 86.966041] Normal [mem 0x0000000100000000-0x00000017ffffffff] >[ 86.972631] Movable zone start for each node >[ 86.977179] Early memory node ranges >[ 86.980985] node 0: [mem 0x0000000000200000-0x000000000021ffff] >[ 86.987666] node 0: [mem 0x0000000000820000-0x000000000307ffff] >[ 86.994348] node 0: [mem 0x0000000003080000-0x000000000308ffff] >[ 87.001029] node 0: [mem 0x0000000003090000-0x00000000031fffff] >[ 87.007710] node 0: [mem 0x0000000003200000-0x00000000033fffff] >[ 87.014392] node 0: [mem 0x0000000003410000-0x000000000563ffff] >[ 87.021073] node 0: [mem 0x0000000005640000-0x000000000567ffff] >[ 87.027754] node 0: [mem 0x0000000005680000-0x00000000056dffff] >[ 87.034435] node 0: [mem 0x00000000056e0000-0x00000000086fffff] >[ 87.041117] node 0: [mem 0x0000000008700000-0x000000000871ffff] >[ 87.047798] node 0: [mem 0x0000000008720000-0x000000000894ffff] >[ 87.054479] node 0: [mem 0x0000000008950000-0x0000000008baffff] >[ 87.061161] node 0: [mem 0x0000000008bb0000-0x0000000008bcffff] >[ 87.067842] node 0: [mem 0x0000000008bd0000-0x0000000008c4ffff] >[ 87.074524] node 0: [mem 0x0000000008c50000-0x0000000008e2ffff] >[ 87.081205] node 0: [mem 0x0000000008e30000-0x0000000008e4ffff] >[ 87.087886] node 0: [mem 0x0000000008e50000-0x0000000008fcffff] >[ 87.094568] node 0: [mem 0x0000000008fd0000-0x000000000910ffff] >[ 87.101249] node 0: [mem 0x0000000009110000-0x00000000092effff] >[ 87.107930] node 0: [mem 0x00000000092f0000-0x000000000930ffff] >[ 87.114612] node 0: [mem 0x0000000009310000-0x000000000963ffff] >[ 87.121293] node 0: [mem 0x0000000009640000-0x000000000e61ffff] >[ 87.127975] node 0: [mem 0x000000000e620000-0x000000000e64ffff] >[ 87.134657] node 0: [mem 0x000000000e650000-0x000000000fffffff] >[ 87.141338] node 0: [mem 0x0000000010800000-0x0000000017feffff] >[ 87.148019] node 0: [mem 0x000000001c000000-0x000000001c00ffff] >[ 87.154701] node 0: [mem 0x000000001c010000-0x000000001c7fffff] >[ 87.161383] node 0: [mem 0x000000001c810000-0x000000007efbffff] >[ 87.168064] node 0: [mem 0x000000007efc0000-0x000000007efdffff] >[ 87.174746] node 0: [mem 0x000000007efe0000-0x000000007efeffff] >[ 87.181427] node 0: [mem 0x000000007eff0000-0x000000007effffff] >[ 87.188108] node 0: [mem 0x000000007f000000-0x00000017ffffffff] Hi, Jia I haven't taken a deep look into your code, just one curious question on your memory layout. The log above is printed out in free_area_init_nodes(), which iterates on memblock.memory and prints them. If I am not wrong, memory regions added to memblock.memory are ordered and merged if possible. While from your log, I see many regions could be merged but are isolated. For example, the last two region: node 0: [mem 0x000000007eff0000-0x000000007effffff] node 0: [mem 0x000000007f000000-0x00000017ffffffff] So I am curious why they are isolated instead of combined to one. >>From the code, the possible reason is the region's flag differs from each other. If you have time, would you mind taking a look into this? -- Wei Yang Help you, Help me