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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 36C77C6778C for ; Fri, 6 Jul 2018 08:15:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9EA323F4C for ; Fri, 6 Jul 2018 08:15:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FB0ljqP3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9EA323F4C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754038AbeGFIP3 (ORCPT ); Fri, 6 Jul 2018 04:15:29 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:36303 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753610AbeGFIP0 (ORCPT ); Fri, 6 Jul 2018 04:15:26 -0400 Received: by mail-pf0-f194.google.com with SMTP id u16-v6so7780428pfh.3 for ; Fri, 06 Jul 2018 01:15:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=M4lUapXVAyrWXwX+FZXA04S5ONE2QLINrxH7fBNkdn4=; b=FB0ljqP3jrw94czePvXM8wmi3K5GbTMIcIyOqEle5lEzSR4ALIRNgrskUyVmvH3aP2 o7W0myWvRd53+8m1hjDmhwtnLpKNhH6TxhrjfmSgb1USVnzT17+nsc0OLtxwfhEDWgqi j/53IZVRCkysrV8oomKln7ZUU1TiglhGXxWIdE5urRhMy1PZJtGpYUKbojG1/FkuqIdr fvPntoLv3h7DGSvKoMOzEGCHS/iDKfi/ODeCaISaW+Ef7T1oGsRB7xErg7nvGt5rpHez jlQpPYvV5M3K43DLU20Ef4Bws4jkQLytOPcCOfoLq5aaMtbUaHZDvPQxKvLqxuk/CYpR busA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=M4lUapXVAyrWXwX+FZXA04S5ONE2QLINrxH7fBNkdn4=; b=YQi9THkBnxWyWWPgoM6MX4PyzaDVLtJpmTbIwuvZYv0SbmAJJFt5Z2RmjFSoNOa9HW 9IxJMrA1r1YDW0sGdUe9PSFTYgeNtv0Ddlek1oApwCdfjn08Z+UJbdHtRB14GOEc4W3q w1Jo+87TLTj6+FnzqG8tC0MBhHoM2FdzWDqFeawgVgW91PcPQcpfrlI4EGGVaNf02N/U wG5eeAC567isPW2HGMj7qLb8aQrzzx3gjxgVAgL2p6PKwgAsCWci8Xr9ZWfDRoPhRA/j HS2up3pXHutBtX1CagmyPWfj+ObKHPOkURADJnP+XqQofd5GEZsaGMxeI6/U6U9tQEdn JZdQ== X-Gm-Message-State: APt69E1Nm7hruVDR6aVs6UxbldGUtidPvWu5Bgb8kFHm/tX7c2mEVOKd vWrQcqE3lwQLL6u7SR6CqE4= X-Google-Smtp-Source: AAOMgpeEUEce5o4yvRMN6z0P/bf9SsD7zzGthwQg0bf+tIOo0cJrDpFOwIX04n19Y+H4fAwFEYqb4A== X-Received: by 2002:a62:8917:: with SMTP id v23-v6mr9738853pfd.127.1530864925835; Fri, 06 Jul 2018 01:15:25 -0700 (PDT) Received: from ct7host.localdomain ([38.106.11.25]) by smtp.gmail.com with ESMTPSA id c141-v6sm4673049pfc.25.2018.07.06.01.15.13 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Jul 2018 01:15:25 -0700 (PDT) From: Jia He To: Russell King , Andrew Morton , Michal Hocko , Catalin Marinas , Mel Gorman , Will Deacon , Mark Rutland , "H. Peter Anvin" Cc: 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 , Ard Biesheuvel , Steve Capper , Thomas Gleixner , Ingo Molnar , Greg Kroah-Hartman , Kate Stewart , Philippe Ombredanne , Johannes Weiner , Kemi Wang , Petr Tesarik , YASUAKI ISHIMATSU , Andrey Ryabinin , Nikolay Borisov , richard.weiyang@gmail.com, Jia He Subject: [PATCH v10 3/6] mm: page_alloc: reduce unnecessary binary search in memblock_next_valid_pfn() Date: Fri, 6 Jul 2018 16:14:17 +0800 Message-Id: <1530864860-7671-4-git-send-email-hejianet@gmail.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1530864860-7671-1-git-send-email-hejianet@gmail.com> References: <1530864860-7671-1-git-send-email-hejianet@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jia He Commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") optimized the loop in memmap_init_zone(). But there is still some room for improvement. E.g. if pfn and pfn+1 are in the same memblock region, we can simply pfn++ instead of doing the binary search in memblock_next_valid_pfn. Furthermore, if the pfn is in a gap of two memory region, skip to next region directly if possible. Attached the memblock region information in my server. [ 0.000000] Zone ranges: [ 0.000000] DMA32 [mem 0x0000000000200000-0x00000000ffffffff] [ 0.000000] Normal [mem 0x0000000100000000-0x00000017ffffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000000200000-0x000000000021ffff] [ 0.000000] node 0: [mem 0x0000000000820000-0x000000000307ffff] [ 0.000000] node 0: [mem 0x0000000003080000-0x000000000308ffff] [ 0.000000] node 0: [mem 0x0000000003090000-0x00000000031fffff] [ 0.000000] node 0: [mem 0x0000000003200000-0x00000000033fffff] [ 0.000000] node 0: [mem 0x0000000003410000-0x00000000034fffff] [ 0.000000] node 0: [mem 0x0000000003500000-0x000000000351ffff] [ 0.000000] node 0: [mem 0x0000000003520000-0x000000000353ffff] [ 0.000000] node 0: [mem 0x0000000003540000-0x0000000003e3ffff] [ 0.000000] node 0: [mem 0x0000000003e40000-0x0000000003e7ffff] [ 0.000000] node 0: [mem 0x0000000003e80000-0x0000000003ecffff] [ 0.000000] node 0: [mem 0x0000000003ed0000-0x0000000003ed5fff] [ 0.000000] node 0: [mem 0x0000000003ed6000-0x0000000006eeafff] [ 0.000000] node 0: [mem 0x0000000006eeb000-0x000000000710ffff] [ 0.000000] node 0: [mem 0x0000000007110000-0x0000000007f0ffff] [ 0.000000] node 0: [mem 0x0000000007f10000-0x0000000007faffff] [ 0.000000] node 0: [mem 0x0000000007fb0000-0x000000000806ffff] [ 0.000000] node 0: [mem 0x0000000008070000-0x00000000080affff] [ 0.000000] node 0: [mem 0x00000000080b0000-0x000000000832ffff] [ 0.000000] node 0: [mem 0x0000000008330000-0x000000000836ffff] [ 0.000000] node 0: [mem 0x0000000008370000-0x000000000838ffff] [ 0.000000] node 0: [mem 0x0000000008390000-0x00000000083a9fff] [ 0.000000] node 0: [mem 0x00000000083aa000-0x00000000083bbfff] [ 0.000000] node 0: [mem 0x00000000083bc000-0x00000000083fffff] [ 0.000000] node 0: [mem 0x0000000008400000-0x000000000841ffff] [ 0.000000] node 0: [mem 0x0000000008420000-0x000000000843ffff] [ 0.000000] node 0: [mem 0x0000000008440000-0x000000000865ffff] [ 0.000000] node 0: [mem 0x0000000008660000-0x000000000869ffff] [ 0.000000] node 0: [mem 0x00000000086a0000-0x00000000086affff] [ 0.000000] node 0: [mem 0x00000000086b0000-0x00000000086effff] [ 0.000000] node 0: [mem 0x00000000086f0000-0x0000000008b6ffff] [ 0.000000] node 0: [mem 0x0000000008b70000-0x0000000008bbffff] [ 0.000000] node 0: [mem 0x0000000008bc0000-0x0000000008edffff] [ 0.000000] node 0: [mem 0x0000000008ee0000-0x0000000008ee0fff] [ 0.000000] node 0: [mem 0x0000000008ee1000-0x0000000008ee2fff] [ 0.000000] node 0: [mem 0x0000000008ee3000-0x000000000decffff] [ 0.000000] node 0: [mem 0x000000000ded0000-0x000000000defffff] [ 0.000000] node 0: [mem 0x000000000df00000-0x000000000fffffff] [ 0.000000] node 0: [mem 0x0000000010800000-0x0000000017feffff] [ 0.000000] node 0: [mem 0x000000001c000000-0x000000001c00ffff] [ 0.000000] node 0: [mem 0x000000001c010000-0x000000001c7fffff] [ 0.000000] node 0: [mem 0x000000001c810000-0x000000007efbffff] [ 0.000000] node 0: [mem 0x000000007efc0000-0x000000007efdffff] [ 0.000000] node 0: [mem 0x000000007efe0000-0x000000007efeffff] [ 0.000000] node 0: [mem 0x000000007eff0000-0x000000007effffff] [ 0.000000] node 0: [mem 0x000000007f000000-0x00000017ffffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000000200000-0x00000017ffffffff] [ 0.000000] On node 0 totalpages: 25145296 [ 0.000000] DMA32 zone: 16376 pages used for memmap [ 0.000000] DMA32 zone: 0 pages reserved [ 0.000000] DMA32 zone: 1028048 pages, LIFO batch:31 [ 0.000000] Normal zone: 376832 pages used for memmap [ 0.000000] Normal zone: 24117248 pages, LIFO batch:31 Signed-off-by: Jia He --- mm/memblock.c | 37 +++++++++++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 8 deletions(-) diff --git a/mm/memblock.c b/mm/memblock.c index ccad225..84f7fa7 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1140,31 +1140,52 @@ int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size, #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ #ifdef CONFIG_HAVE_MEMBLOCK_PFN_VALID +static int early_region_idx __init_memblock = -1; ulong __init_memblock memblock_next_valid_pfn(ulong pfn) { struct memblock_type *type = &memblock.memory; - unsigned int right = type->cnt; - unsigned int mid, left = 0; + struct memblock_region *regions = type->regions; + uint right = type->cnt; + uint mid, left = 0; + ulong start_pfn, end_pfn, next_start_pfn; phys_addr_t addr = PFN_PHYS(++pfn); + /* fast path, return pfn+1 if next pfn is in the same region */ + if (early_region_idx != -1) { + start_pfn = PFN_DOWN(regions[early_region_idx].base); + end_pfn = PFN_DOWN(regions[early_region_idx].base + + regions[early_region_idx].size); + + if (pfn >= start_pfn && pfn < end_pfn) + return pfn; + + early_region_idx++; + next_start_pfn = PFN_DOWN(regions[early_region_idx].base); + + if (pfn >= end_pfn && pfn <= next_start_pfn) + return next_start_pfn; + } + + /* slow path, do the binary searching */ do { mid = (right + left) / 2; - if (addr < type->regions[mid].base) + if (addr < regions[mid].base) right = mid; - else if (addr >= (type->regions[mid].base + - type->regions[mid].size)) + else if (addr >= (regions[mid].base + regions[mid].size)) left = mid + 1; else { - /* addr is within the region, so pfn is valid */ + early_region_idx = mid; return pfn; } } while (left < right); if (right == type->cnt) return -1UL; - else - return PHYS_PFN(type->regions[right].base); + + early_region_idx = right; + + return PHYS_PFN(regions[early_region_idx].base); } EXPORT_SYMBOL(memblock_next_valid_pfn); #endif /*CONFIG_HAVE_MEMBLOCK_PFN_VALID*/ -- 1.8.3.1