get:
Show a patch.

patch:
Update a patch.

put:
Update a patch.

GET /api/1.2/patches/831045/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 831045,
    "url": "http://patchwork.ozlabs.org/api/1.2/patches/831045/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20171027040833.3644-3-aneesh.kumar@linux.vnet.ibm.com/",
    "project": {
        "id": 2,
        "url": "http://patchwork.ozlabs.org/api/1.2/projects/2/?format=api",
        "name": "Linux PPC development",
        "link_name": "linuxppc-dev",
        "list_id": "linuxppc-dev.lists.ozlabs.org",
        "list_email": "linuxppc-dev@lists.ozlabs.org",
        "web_url": "https://github.com/linuxppc/wiki/wiki",
        "scm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git",
        "webscm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/",
        "list_archive_url": "https://lore.kernel.org/linuxppc-dev/",
        "list_archive_url_format": "https://lore.kernel.org/linuxppc-dev/{}/",
        "commit_url_format": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}"
    },
    "msgid": "<20171027040833.3644-3-aneesh.kumar@linux.vnet.ibm.com>",
    "list_archive_url": "https://lore.kernel.org/linuxppc-dev/20171027040833.3644-3-aneesh.kumar@linux.vnet.ibm.com/",
    "date": "2017-10-27T04:08:19",
    "name": "[02/16] powerpc/mm: Update native_hpte_find to return hash pte",
    "commit_ref": null,
    "pull_url": null,
    "state": "changes-requested",
    "archived": false,
    "hash": "1e2977578359d770dc777f39a35e6bf0b5962f77",
    "submitter": {
        "id": 664,
        "url": "http://patchwork.ozlabs.org/api/1.2/people/664/?format=api",
        "name": "Aneesh Kumar K.V",
        "email": "aneesh.kumar@linux.vnet.ibm.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20171027040833.3644-3-aneesh.kumar@linux.vnet.ibm.com/mbox/",
    "series": [
        {
            "id": 10486,
            "url": "http://patchwork.ozlabs.org/api/1.2/series/10486/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=10486",
            "date": "2017-10-27T04:08:17",
            "name": "Remove hash page table slot tracking from linux PTE",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/10486/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/831045/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/831045/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>",
        "X-Original-To": [
            "patchwork-incoming@ozlabs.org",
            "linuxppc-dev@lists.ozlabs.org"
        ],
        "Delivered-To": [
            "patchwork-incoming@ozlabs.org",
            "linuxppc-dev@lists.ozlabs.org"
        ],
        "Received": [
            "from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\t(using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3yNVrs6bGsz9t0F\n\tfor <patchwork-incoming@ozlabs.org>;\n\tFri, 27 Oct 2017 15:14:53 +1100 (AEDT)",
            "from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 3yNVrs5kSPzDsG0\n\tfor <patchwork-incoming@ozlabs.org>;\n\tFri, 27 Oct 2017 15:14:53 +1100 (AEDT)",
            "from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com\n\t[148.163.156.1])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256\n\tbits)) (No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 3yNVkF16tXzDrcR\n\tfor <linuxppc-dev@lists.ozlabs.org>;\n\tFri, 27 Oct 2017 15:09:08 +1100 (AEDT)",
            "from pps.filterd (m0098396.ppops.net [127.0.0.1])\n\tby mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id\n\tv9R495tg140054\n\tfor <linuxppc-dev@lists.ozlabs.org>; Fri, 27 Oct 2017 00:09:06 -0400",
            "from e33.co.us.ibm.com (e33.co.us.ibm.com [32.97.110.151])\n\tby mx0a-001b2d01.pphosted.com with ESMTP id 2dusbaadn8-1\n\t(version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT)\n\tfor <linuxppc-dev@lists.ozlabs.org>; Fri, 27 Oct 2017 00:09:06 -0400",
            "from localhost\n\tby e33.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use\n\tOnly! Violators will be prosecuted\n\tfor <linuxppc-dev@lists.ozlabs.org> from\n\t<aneesh.kumar@linux.vnet.ibm.com>; Thu, 26 Oct 2017 22:09:00 -0600",
            "from b03cxnp07029.gho.boulder.ibm.com (9.17.130.16)\n\tby e33.co.us.ibm.com (192.168.1.133) with IBM ESMTP SMTP Gateway:\n\tAuthorized Use Only! Violators will be prosecuted; \n\tThu, 26 Oct 2017 22:08:56 -0600",
            "from b03ledav001.gho.boulder.ibm.com\n\t(b03ledav001.gho.boulder.ibm.com [9.17.130.232])\n\tby b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with\n\tESMTP id v9R48uDa8323440; Thu, 26 Oct 2017 21:08:56 -0700",
            "from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id 43A416E175;\n\tThu, 26 Oct 2017 22:08:56 -0600 (MDT)",
            "from skywalker.ibmmodules.com (unknown [9.85.199.61])\n\tby b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP id 8519B6E121;\n\tThu, 26 Oct 2017 22:08:52 -0600 (MDT)"
        ],
        "Authentication-Results": "ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com\n\t(client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com;\n\tenvelope-from=aneesh.kumar@linux.vnet.ibm.com; receiver=<UNKNOWN>)",
        "From": "\"Aneesh Kumar K.V\" <aneesh.kumar@linux.vnet.ibm.com>",
        "To": "benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au",
        "Subject": "[PATCH 02/16] powerpc/mm: Update native_hpte_find to return hash pte",
        "Date": "Fri, 27 Oct 2017 09:38:19 +0530",
        "X-Mailer": "git-send-email 2.13.6",
        "In-Reply-To": "<20171027040833.3644-1-aneesh.kumar@linux.vnet.ibm.com>",
        "References": "<20171027040833.3644-1-aneesh.kumar@linux.vnet.ibm.com>",
        "X-TM-AS-GCONF": "00",
        "x-cbid": "17102704-0008-0000-0000-000008C6653C",
        "X-IBM-SpamModules-Scores": "",
        "X-IBM-SpamModules-Versions": "BY=3.00007958; HX=3.00000241; KW=3.00000007;\n\tPH=3.00000004; SC=3.00000239; SDB=6.00937034; UDB=6.00472245;\n\tIPR=6.00717297; \n\tBA=6.00005660; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009;\n\tZB=6.00000000; \n\tZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00017735;\n\tXFM=3.00000015; UTC=2017-10-27 04:08:58",
        "X-IBM-AV-DETECTION": "SAVI=unused REMOTE=unused XFE=unused",
        "x-cbparentid": "17102704-0009-0000-0000-0000448687B2",
        "Message-Id": "<20171027040833.3644-3-aneesh.kumar@linux.vnet.ibm.com>",
        "X-Proofpoint-Virus-Version": "vendor=fsecure engine=2.50.10432:, ,\n\tdefinitions=2017-10-27_02:, , signatures=0",
        "X-Proofpoint-Spam-Details": "rule=outbound_notspam policy=outbound score=0\n\tpriorityscore=1501\n\tmalwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0\n\tclxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0\n\tclassifier=spam adjust=0 reason=mlx scancount=1\n\tengine=8.0.1-1707230000\n\tdefinitions=main-1710270053",
        "X-BeenThere": "linuxppc-dev@lists.ozlabs.org",
        "X-Mailman-Version": "2.1.24",
        "Precedence": "list",
        "List-Id": "Linux on PowerPC Developers Mail List\n\t<linuxppc-dev.lists.ozlabs.org>",
        "List-Unsubscribe": "<https://lists.ozlabs.org/options/linuxppc-dev>,\n\t<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.ozlabs.org/pipermail/linuxppc-dev/>",
        "List-Post": "<mailto:linuxppc-dev@lists.ozlabs.org>",
        "List-Help": "<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>",
        "List-Subscribe": "<https://lists.ozlabs.org/listinfo/linuxppc-dev>,\n\t<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>",
        "Cc": "linuxppc-dev@lists.ozlabs.org,\n\t\"Aneesh Kumar K.V\" <aneesh.kumar@linux.vnet.ibm.com>",
        "Errors-To": "linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org",
        "Sender": "\"Linuxppc-dev\"\n\t<linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>"
    },
    "content": "The helper now also does a secondary hash search so that we can use this in other\nfunctions.\n\nSigned-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>\n---\n arch/powerpc/mm/hash_native_64.c | 73 ++++++++++++++++++++++++----------------\n 1 file changed, 44 insertions(+), 29 deletions(-)",
    "diff": "diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c\nindex 3848af167df9..496b1680ba24 100644\n--- a/arch/powerpc/mm/hash_native_64.c\n+++ b/arch/powerpc/mm/hash_native_64.c\n@@ -351,32 +351,49 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,\n \treturn ret;\n }\n \n-static long native_hpte_find(unsigned long vpn, int psize, int ssize)\n+/* returns a locked hash pte */\n+struct hash_pte *native_hpte_find(unsigned long hash, unsigned long vpn,\n+\t\t\t\t  unsigned long bpsize, unsigned long ssize)\n {\n+\tint i;\n+\tunsigned long hpte_v;\n \tstruct hash_pte *hptep;\n-\tunsigned long hash;\n-\tunsigned long i;\n-\tlong slot;\n-\tunsigned long want_v, hpte_v;\n-\n-\thash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);\n-\twant_v = hpte_encode_avpn(vpn, psize, ssize);\n+\tunsigned long want_v, slot;\n+\tbool secondary_search = false;\n \n-\t/* Bolted mappings are only ever in the primary group */\n+\twant_v = hpte_encode_avpn(vpn, bpsize, ssize);\n \tslot = (hash & htab_hash_mask) * HPTES_PER_GROUP;\n-\tfor (i = 0; i < HPTES_PER_GROUP; i++) {\n-\t\thptep = htab_address + slot;\n+\n+\t/*\n+\t * search for hpte in the primary group\n+\t */\n+search_again:\n+\thptep = htab_address + slot;\n+\tfor (i = 0; i < HPTES_PER_GROUP; i++, hptep++) {\n+\t\t/* check locklessly first */\n \t\thpte_v = be64_to_cpu(hptep->v);\n \t\tif (cpu_has_feature(CPU_FTR_ARCH_300))\n \t\t\thpte_v = hpte_new_to_old_v(hpte_v, be64_to_cpu(hptep->r));\n+\t\tif (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))\n+\t\t\tcontinue;\n \n-\t\tif (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))\n-\t\t\t/* HPTE matches */\n-\t\t\treturn slot;\n-\t\t++slot;\n+\t\tnative_lock_hpte(hptep);\n+\t\thpte_v = be64_to_cpu(hptep->v);\n+\t\tif (cpu_has_feature(CPU_FTR_ARCH_300))\n+\t\t\thpte_v = hpte_new_to_old_v(hpte_v, be64_to_cpu(hptep->r));\n+\t\tif (unlikely(!HPTE_V_COMPARE(hpte_v, want_v) ||\n+\t\t\t     !(hpte_v & HPTE_V_VALID)))\n+\t\t\tnative_unlock_hpte(hptep);\n+\t\telse\n+\t\t\treturn hptep;\n \t}\n-\n-\treturn -1;\n+\tif (!secondary_search) {\n+\t\t/* Search for hpte in the secondary group */\n+\t\tslot = (~hash & htab_hash_mask) * HPTES_PER_GROUP;\n+\t\tsecondary_search = true;\n+\t\tgoto search_again;\n+\t}\n+\treturn NULL;\n }\n \n /*\n@@ -389,23 +406,22 @@ static long native_hpte_find(unsigned long vpn, int psize, int ssize)\n static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,\n \t\t\t\t       int psize, int ssize)\n {\n-\tunsigned long vpn;\n-\tunsigned long vsid;\n-\tlong slot;\n+\tunsigned long hash;\n+\tunsigned long vpn, vsid;\n \tstruct hash_pte *hptep;\n \n \tvsid = get_kernel_vsid(ea, ssize);\n \tvpn = hpt_vpn(ea, vsid, ssize);\n-\n-\tslot = native_hpte_find(vpn, psize, ssize);\n-\tif (slot == -1)\n+\thash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);\n+\thptep = native_hpte_find(hash, vpn, psize, ssize);\n+\tif (!hptep)\n \t\tpanic(\"could not find page to bolt\\n\");\n-\thptep = htab_address + slot;\n \n \t/* Update the HPTE */\n \thptep->r = cpu_to_be64((be64_to_cpu(hptep->r) &\n \t\t\t\t~(HPTE_R_PPP | HPTE_R_N)) |\n \t\t\t       (newpp & (HPTE_R_PPP | HPTE_R_N)));\n+\tnative_unlock_hpte(hptep);\n \t/*\n \t * Ensure it is out of the tlb too. Bolted entries base and\n \t * actual page size will be same.\n@@ -422,18 +438,17 @@ static int native_hpte_removebolted(unsigned long ea, int psize, int ssize)\n {\n \tunsigned long vpn;\n \tunsigned long vsid;\n-\tlong slot;\n+\tunsigned long hash;\n \tstruct hash_pte *hptep;\n \n \tvsid = get_kernel_vsid(ea, ssize);\n \tvpn = hpt_vpn(ea, vsid, ssize);\n+\thash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);\n \n-\tslot = native_hpte_find(vpn, psize, ssize);\n-\tif (slot == -1)\n+\thptep = native_hpte_find(hash, vpn, psize, ssize);\n+\tif (!hptep)\n \t\treturn -ENOENT;\n \n-\thptep = htab_address + slot;\n-\n \tVM_WARN_ON(!(be64_to_cpu(hptep->v) & HPTE_V_BOLTED));\n \n \t/* Invalidate the hpte */\n",
    "prefixes": [
        "02/16"
    ]
}