{"id":814820,"url":"http://patchwork.ozlabs.org/api/patches/814820/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20170918082706.6485-4-npiggin@gmail.com/","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/projects/2/?format=json","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":"<20170918082706.6485-4-npiggin@gmail.com>","list_archive_url":"https://lore.kernel.org/linuxppc-dev/20170918082706.6485-4-npiggin@gmail.com/","date":"2017-09-18T08:27:04","name":"[3/5] powerpc/watchdog: do not trigger SMP crash from touch_nmi_watchdog","commit_ref":null,"pull_url":null,"state":"superseded","archived":true,"hash":"3e55ee46e86e9a8b7bf7b232ac1e76da316e6fd8","submitter":{"id":69518,"url":"http://patchwork.ozlabs.org/api/people/69518/?format=json","name":"Nicholas Piggin","email":"npiggin@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20170918082706.6485-4-npiggin@gmail.com/mbox/","series":[{"id":3584,"url":"http://patchwork.ozlabs.org/api/series/3584/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=3584","date":"2017-09-18T08:27:01","name":"More NMI IPI enablement work","version":1,"mbox":"http://patchwork.ozlabs.org/series/3584/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/814820/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/814820/checks/","tags":{},"related":[],"headers":{"Return-Path":"","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 3xwfST1wcWz9rxm\n\tfor ;\n\tMon, 18 Sep 2017 18:34:33 +1000 (AEST)","from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 3xwfST0mGPzDrhL\n\tfor ;\n\tMon, 18 Sep 2017 18:34:33 +1000 (AEST)","from mail-pf0-x244.google.com (mail-pf0-x244.google.com\n\t[IPv6:2607:f8b0:400e:c00::244])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128\n\tbits)) (No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 3xwfJK3p2NzDrWb\n\tfor ;\n\tMon, 18 Sep 2017 18:27:29 +1000 (AEST)","by mail-pf0-x244.google.com with SMTP id g65so4307992pfe.1\n\tfor ;\n\tMon, 18 Sep 2017 01:27:29 -0700 (PDT)","from roar.au.ibm.com ([210.185.119.235])\n\tby smtp.gmail.com with ESMTPSA id\n\td18sm14293750pfk.11.2017.09.18.01.27.24\n\t(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);\n\tMon, 18 Sep 2017 01:27:26 -0700 (PDT)"],"Authentication-Results":["ozlabs.org; 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a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to\n\t:references;\n\tbh=dIuhdcgQkWcIO/kJZuDXIDQcxsryi1QYzM1OPwkIVZ0=;\n\tb=QfRXnrtsDC5OdfdtRJAsJydXaMghnfsrhADO2X/8dWcheUzjV+wdstoc3O3WieR/TJ\n\tV7h/vsYd9kUf1VgxGwSwokDJ+ByZElpwpOxX9aMHi3e+RFpn/6eMWTPvw95GqqBIfvnR\n\tDJUM0kuJk2lcAHLBT/MS5byQbM+E9otJfaO8JNq/eyluG52iD5kyJc+ODUDJx9E7ZIYu\n\tjODRyMNv5zQeqVc7w3DbTMpgkjI/+loo2eCsupeGPCL4YRcW07U0tvDQYjQsDJvP/G0a\n\tGkcpXDAwE2u7CqmrmG2lASDi/MZ+Uk9HFKvVTG2gl/X7/N9OR58mkTwJqBrKnhcVHI8y\n\t3zJw==","X-Gm-Message-State":"AHPjjUj88d0AS6l5Lk40b/WGcuXwXZdUQTeNKMAJUcoebiEkNH3HM6LU\n\tmhPCGn+UY8aFN98x","X-Google-Smtp-Source":"ADKCNb5B6f76xbUH5CO33qyE0M/bAntTJkkCaNS/fWK1ct0dwDh0I42kXo6ntyt+Mm4v+ale40h9ag==","X-Received":"by 10.84.238.198 with SMTP id l6mr34945072pln.152.1505723247062; \n\tMon, 18 Sep 2017 01:27:27 -0700 (PDT)","From":"Nicholas Piggin ","To":"linuxppc-dev@lists.ozlabs.org","Subject":"[PATCH 3/5] powerpc/watchdog: do not trigger SMP crash from\n\ttouch_nmi_watchdog","Date":"Mon, 18 Sep 2017 18:27:04 +1000","Message-Id":"<20170918082706.6485-4-npiggin@gmail.com>","X-Mailer":"git-send-email 2.13.3","In-Reply-To":"<20170918082706.6485-1-npiggin@gmail.com>","References":"<20170918082706.6485-1-npiggin@gmail.com>","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","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Cc":"Nicholas Piggin ","Errors-To":"linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org","Sender":"\"Linuxppc-dev\"\n\t"},"content":"In xmon, touch_nmi_watchdog() is not expected to be checking that\nother CPUs have not touched the watchdog, so the code will just\ncall touch_nmi_watchdog() once before re-enabling hard interrupts.\n\nJust update our CPU's state, and ignore apparently stuck SMP threads.\n\nArguably touch_nmi_watchdog should check for SMP lockups, and\ncallers should be fixed, but that's not trivial for the input code\nof xmon.\n---\n arch/powerpc/kernel/watchdog.c | 7 +++++--\n 1 file changed, 5 insertions(+), 2 deletions(-)","diff":"diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c\nindex 920e61c79f47..1fb9379dc683 100644\n--- a/arch/powerpc/kernel/watchdog.c\n+++ b/arch/powerpc/kernel/watchdog.c\n@@ -277,9 +277,12 @@ void arch_touch_nmi_watchdog(void)\n {\n \tunsigned long ticks = tb_ticks_per_usec * wd_timer_period_ms * 1000;\n \tint cpu = smp_processor_id();\n+\tu64 tb = get_tb();\n \n-\tif (get_tb() - per_cpu(wd_timer_tb, cpu) >= ticks)\n-\t\twatchdog_timer_interrupt(cpu);\n+\tif (tb - per_cpu(wd_timer_tb, cpu) >= ticks) {\n+\t\tper_cpu(wd_timer_tb, cpu) = tb;\n+\t\twd_smp_clear_cpu_pending(cpu, tb);\n+\t}\n }\n EXPORT_SYMBOL(arch_touch_nmi_watchdog);\n \n","prefixes":["3/5"]}