From patchwork Fri Jan 26 03:03:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "\(Exiting\) Baolin Wang" X-Patchwork-Id: 125888 Delivered-To: patch@linaro.org Received: by 10.46.84.92 with SMTP id y28csp22908ljd; Thu, 25 Jan 2018 19:04:23 -0800 (PST) X-Google-Smtp-Source: AH8x227okpOtB0e5GXgfQSG2eHobx+d5pRwr5sRehjksuuCYDelz6wzMqj35gFdxFpk8WnAFvFnD X-Received: by 10.99.122.18 with SMTP id v18mr15180525pgc.128.1516935863347; Thu, 25 Jan 2018 19:04:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1516935863; cv=none; d=google.com; s=arc-20160816; b=RrB32qFW0KRovdM7wzOhPmjHUmubGpvDsWbFENv5Glaw1QnQBAwxMaFeuMAWPSHmY/ AlECqJX8cePDFfSDW50uwQ4/SXxA+dzjpb2SZBS8TRM6wMvgbGLgoCm410lVentBp9Zx 725FOoKDkZEMjSNlOsD/eeu1m7/2AyC6GHbbZRhBF2zXf4XRCq/xjtHZPZ1q1qiFEx/2 ZBlc7fqby1RF7TRb0Q5kG9OBbmToEzbw1EU5zfz6IhTTu/i1ZuO+n+jdQ/mEjc2/0soF 9eNhUZc/Mnmed0Vg+88+dDZEF/OgNNo5QifO2p0BiptjFvN7sZ+8f/RPwTI9wLE44d8N 36xA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=L4BB4WebRhmvM7QPzbe4dIBHpNjACDdFd0AjD7Pi3zw=; b=nxcOloypIkiv79SE2eiwjP75iwIKQd2IE2By2sRD0iVp0WUliTJN1t0XZT4efs7JFa 8s6wwcpr+OMdO6uPZPwEQqPIn9UD8u+Kz4XCW6I3D4VsHRdZDnJotIgqVSr0UNgGsLzz /3nVGuSf7L/TPfUEZLj5238xY9MYh+t9sC3GE7uxUN5ZoSWqyymbCEHBMq1Jxmrs6wdP zOp4LWJ+Xswa2i8EfZxxS8z1DNi2dykqb06T1vq0+cUZUq6oHxMwajKNf0lp3cMZWCFY SKRejDKeYAqifpZlkwPBZejmfAbREzNhPx/TwSGaglgTsdscyTkLd1ufdPI8AnDjWO7j JfMw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=LsLB5ZhE; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o3-v6si2525442pld.605.2018.01.25.19.04.23; Thu, 25 Jan 2018 19:04:23 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=LsLB5ZhE; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751409AbeAZDEV (ORCPT + 28 others); Thu, 25 Jan 2018 22:04:21 -0500 Received: from mail-pg0-f68.google.com ([74.125.83.68]:44541 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751174AbeAZDET (ORCPT ); Thu, 25 Jan 2018 22:04:19 -0500 Received: by mail-pg0-f68.google.com with SMTP id m20so6378000pgc.11 for ; Thu, 25 Jan 2018 19:04:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=L4BB4WebRhmvM7QPzbe4dIBHpNjACDdFd0AjD7Pi3zw=; b=LsLB5ZhEqiG2thrk+AbjnAhRdyEG112N/mkA9HmB62tIYfX18enBWs7Rx28P8zp1QH zvLkWoRciW5/rCsIlAK2eSa6uQJP5DyfzhJcpB7WhIptBZJ/hljrgAvyPELLxBTRCaKQ +xvOGxEDXQX90tINGtqjRXa8/1vuMj7TBj8a8= 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; bh=L4BB4WebRhmvM7QPzbe4dIBHpNjACDdFd0AjD7Pi3zw=; b=dXjj36Q5LcyDQtYd/DLpPTRalCgsBSM0P84Zf+FUjWBFa2tBGA1m35MzuhBo8vceU/ go9q0lune2Ki4JryMPxbK/j/5COwzDoLUIt1yDA+h5UzZWYR3z3hQrp5F1BRUhzC4n5C 9zySBmD+TG9IDwrsbUgoIZ6xP3dvR9bLxULMj32SLjGbinc4GkHHvc5QtFQNmi1sKwZK EHETSTmIhqV4lbZqxu5XV+Fvcj9h4+8gOkjZO+P/jGYhe5995V+w7Ke/gsp9Q4JN3q0c caEsPwRDmQNMeMgig0KhSL2rvESpuj/p7VtoPslPvXVi31vAtULvKdJwcNGiFMrhI2/2 8wsA== X-Gm-Message-State: AKwxytc4HoaTHUnJVhEp6x3wfiLYBFjxnkHzrIKykErlomfhG+vtzX1V REkytmvPLPWNuQJcqi2j6w4kyQ== X-Received: by 10.98.73.157 with SMTP id r29mr18026904pfi.41.1516935859499; Thu, 25 Jan 2018 19:04:19 -0800 (PST) Received: from baolinwangubtpc.spreadtrum.com ([117.18.48.82]) by smtp.gmail.com with ESMTPSA id r12sm15133720pfh.153.2018.01.25.19.04.15 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 25 Jan 2018 19:04:18 -0800 (PST) From: Baolin Wang To: jason.wessel@windriver.com, daniel.thompson@linaro.org Cc: baolin.wang@linaro.org, mingo@kernel.org, arnd@arndb.de, broonie@kernel.org, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: [PATCH] kdb: use ktime_get_seconds() instead of ktime_get_ts() Date: Fri, 26 Jan 2018 11:03:14 +0800 Message-Id: X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The kdb code will print the monotonic time by ktime_get_ts(), but the ktime_get_ts() will be protected by a sequence lock, that will introduce one deadlock risk if the lock was already held in the context from which we entered the debugger. Since kdb is only interested in the second field, we can use the ktime_get_seconds() to get the monotonic time without a lock, moreover we can remove the 'struct timespec', which is not y2038 safe. Signed-off-by: Baolin Wang --- kernel/debug/kdb/kdb_main.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) -- 1.7.9.5 Acked-by: Jason Wessel diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 69e70f4..f0fc6f7 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2486,10 +2486,8 @@ static int kdb_kill(int argc, const char **argv) */ static void kdb_sysinfo(struct sysinfo *val) { - struct timespec uptime; - ktime_get_ts(&uptime); memset(val, 0, sizeof(*val)); - val->uptime = uptime.tv_sec; + val->uptime = ktime_get_seconds(); val->loads[0] = avenrun[0]; val->loads[1] = avenrun[1]; val->loads[2] = avenrun[2];