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GET /api/patches/806907/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 806907,
    "url": "http://patchwork.ozlabs.org/api/patches/806907/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/sparclinux/patch/1503972142-289376-8-git-send-email-pasha.tatashin@oracle.com/",
    "project": {
        "id": 10,
        "url": "http://patchwork.ozlabs.org/api/projects/10/?format=api",
        "name": "Linux SPARC Development ",
        "link_name": "sparclinux",
        "list_id": "sparclinux.vger.kernel.org",
        "list_email": "sparclinux@vger.kernel.org",
        "web_url": null,
        "scm_url": null,
        "webscm_url": null,
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<1503972142-289376-8-git-send-email-pasha.tatashin@oracle.com>",
    "list_archive_url": null,
    "date": "2017-08-29T02:02:18",
    "name": "[v7,07/11] sparc64: optimized struct page zeroing",
    "commit_ref": null,
    "pull_url": null,
    "state": "not-applicable",
    "archived": false,
    "hash": "e491f76dd863cd259f8b65b312e161bde30fdecc",
    "submitter": {
        "id": 71010,
        "url": "http://patchwork.ozlabs.org/api/people/71010/?format=api",
        "name": "Pavel Tatashin",
        "email": "pasha.tatashin@oracle.com"
    },
    "delegate": {
        "id": 34,
        "url": "http://patchwork.ozlabs.org/api/users/34/?format=api",
        "username": "davem",
        "first_name": "David",
        "last_name": "Miller",
        "email": "davem@davemloft.net"
    },
    "mbox": "http://patchwork.ozlabs.org/project/sparclinux/patch/1503972142-289376-8-git-send-email-pasha.tatashin@oracle.com/mbox/",
    "series": [
        {
            "id": 285,
            "url": "http://patchwork.ozlabs.org/api/series/285/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/sparclinux/list/?series=285",
            "date": "2017-08-29T02:02:11",
            "name": "complete deferred page initialization",
            "version": 7,
            "mbox": "http://patchwork.ozlabs.org/series/285/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/806907/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/806907/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<sparclinux-owner@vger.kernel.org>",
        "X-Original-To": "patchwork-incoming@ozlabs.org",
        "Delivered-To": "patchwork-incoming@ozlabs.org",
        "Authentication-Results": "ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=sparclinux-owner@vger.kernel.org;\n\treceiver=<UNKNOWN>)",
        "Received": [
            "from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xhBnh2qkNz9s7c\n\tfor <patchwork-incoming@ozlabs.org>;\n\tTue, 29 Aug 2017 12:06:16 +1000 (AEST)",
            "(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751394AbdH2CGO (ORCPT <rfc822;patchwork-incoming@ozlabs.org>);\n\tMon, 28 Aug 2017 22:06:14 -0400",
            "from aserp1040.oracle.com ([141.146.126.69]:25868 \"EHLO\n\taserp1040.oracle.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1751271AbdH2CDu (ORCPT\n\t<rfc822; sparclinux@vger.kernel.org>); Mon, 28 Aug 2017 22:03:50 -0400",
            "from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71])\n\tby aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with\n\tESMTP id v7T22bJ2011059\n\t(version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256\n\tverify=OK); Tue, 29 Aug 2017 02:02:37 GMT",
            "from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72])\n\tby userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id v7T22aeb007095\n\t(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256\n\tverify=OK); Tue, 29 Aug 2017 02:02:36 GMT",
            "from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17])\n\tby userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id\n\tv7T22Zma011213; Tue, 29 Aug 2017 02:02:35 GMT",
            "from ca-ldom-ol-build-1.us.oracle.com (/10.129.68.23)\n\tby default (Oracle Beehive Gateway v4.0)\n\twith ESMTP ; Mon, 28 Aug 2017 19:02:35 -0700"
        ],
        "From": "Pavel Tatashin <pasha.tatashin@oracle.com>",
        "To": "linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org,\n\tlinux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org,\n\tlinux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org,\n\tx86@kernel.org, kasan-dev@googlegroups.com, borntraeger@de.ibm.com,\n\theiko.carstens@de.ibm.com, davem@davemloft.net,\n\twilly@infradead.org, mhocko@kernel.org, ard.biesheuvel@linaro.org,\n\twill.deacon@arm.com, catalin.marinas@arm.com, sam@ravnborg.org,\n\tmgorman@techsingularity.net, Steven.Sistare@oracle.com,\n\tdaniel.m.jordan@oracle.com, bob.picco@oracle.com",
        "Subject": "[PATCH v7 07/11] sparc64: optimized struct page zeroing",
        "Date": "Mon, 28 Aug 2017 22:02:18 -0400",
        "Message-Id": "<1503972142-289376-8-git-send-email-pasha.tatashin@oracle.com>",
        "X-Mailer": "git-send-email 1.7.1",
        "In-Reply-To": "<1503972142-289376-1-git-send-email-pasha.tatashin@oracle.com>",
        "References": "<1503972142-289376-1-git-send-email-pasha.tatashin@oracle.com>",
        "X-Source-IP": "userv0021.oracle.com [156.151.31.71]",
        "Sender": "sparclinux-owner@vger.kernel.org",
        "Precedence": "bulk",
        "List-ID": "<sparclinux.vger.kernel.org>",
        "X-Mailing-List": "sparclinux@vger.kernel.org"
    },
    "content": "Add an optimized mm_zero_struct_page(), so struct page's are zeroed without\ncalling memset(). We do eight to ten regular stores based on the size of\nstruct page. Compiler optimizes out the conditions of switch() statement.\n\nSPARC-M6 with 15T of memory, single thread performance:\n\n                               BASE            FIX  OPTIMIZED_FIX\n        bootmem_init   28.440467985s   2.305674818s   2.305161615s\nfree_area_init_nodes  202.845901673s 225.343084508s 172.556506560s\n                      --------------------------------------------\nTotal                 231.286369658s 227.648759326s 174.861668175s\n\nBASE:  current linux\nFIX:   This patch series without \"optimized struct page zeroing\"\nOPTIMIZED_FIX: This patch series including the current patch.\n\nbootmem_init() is where memory for struct pages is zeroed during\nallocation. Note, about two seconds in this function is a fixed time: it\ndoes not increase as memory is increased.\n\nSigned-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>\nReviewed-by: Steven Sistare <steven.sistare@oracle.com>\nReviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>\nReviewed-by: Bob Picco <bob.picco@oracle.com>\n---\n arch/sparc/include/asm/pgtable_64.h | 30 ++++++++++++++++++++++++++++++\n 1 file changed, 30 insertions(+)",
    "diff": "diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h\nindex 6fbd931f0570..cee5cc7ccc51 100644\n--- a/arch/sparc/include/asm/pgtable_64.h\n+++ b/arch/sparc/include/asm/pgtable_64.h\n@@ -230,6 +230,36 @@ extern unsigned long _PAGE_ALL_SZ_BITS;\n extern struct page *mem_map_zero;\n #define ZERO_PAGE(vaddr)\t(mem_map_zero)\n \n+/* This macro must be updated when the size of struct page grows above 80\n+ * or reduces below 64.\n+ * The idea that compiler optimizes out switch() statement, and only\n+ * leaves clrx instructions\n+ */\n+#define\tmm_zero_struct_page(pp) do {\t\t\t\t\t\\\n+\tunsigned long *_pp = (void *)(pp);\t\t\t\t\\\n+\t\t\t\t\t\t\t\t\t\\\n+\t /* Check that struct page is either 64, 72, or 80 bytes */\t\\\n+\tBUILD_BUG_ON(sizeof(struct page) & 7);\t\t\t\t\\\n+\tBUILD_BUG_ON(sizeof(struct page) < 64);\t\t\t\t\\\n+\tBUILD_BUG_ON(sizeof(struct page) > 80);\t\t\t\t\\\n+\t\t\t\t\t\t\t\t\t\\\n+\tswitch (sizeof(struct page)) {\t\t\t\t\t\\\n+\tcase 80:\t\t\t\t\t\t\t\\\n+\t\t_pp[9] = 0;\t/* fallthrough */\t\t\t\\\n+\tcase 72:\t\t\t\t\t\t\t\\\n+\t\t_pp[8] = 0;\t/* fallthrough */\t\t\t\\\n+\tdefault:\t\t\t\t\t\t\t\\\n+\t\t_pp[7] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[6] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[5] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[4] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[3] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[2] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[1] = 0;\t\t\t\t\t\t\\\n+\t\t_pp[0] = 0;\t\t\t\t\t\t\\\n+\t}\t\t\t\t\t\t\t\t\\\n+} while (0)\n+\n /* PFNs are real physical page numbers.  However, mem_map only begins to record\n  * per-page information starting at pfn_base.  This is to handle systems where\n  * the first physical page in the machine is at some huge physical address,\n",
    "prefixes": [
        "v7",
        "07/11"
    ]
}