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=-23.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 BB4BCC433E3 for ; Fri, 19 Mar 2021 19:32:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8FB476197D for ; Fri, 19 Mar 2021 19:32:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230384AbhCSTcJ (ORCPT ); Fri, 19 Mar 2021 15:32:09 -0400 Received: from linux.microsoft.com ([13.77.154.182]:52734 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230096AbhCSTby (ORCPT ); Fri, 19 Mar 2021 15:31:54 -0400 Received: from sequoia (162-237-133-238.lightspeed.rcsntx.sbcglobal.net [162.237.133.238]) by linux.microsoft.com (Postfix) with ESMTPSA id 1ECB120B39C5; Fri, 19 Mar 2021 12:31:51 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 1ECB120B39C5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1616182311; bh=N17r/UB5T4m4Bg9gnzCLztHW3VZmUbzxtoNM3DmwHFw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=L9Ntx43/LlZ/VyuRPZxURRFTXbXCKyPCJPrdLaW8ihR1pSVc6E7mLW0fIr0JISiuo bRBNd4oTjgp8p9fEEgfGkaL6M3uyVoFrHw14qHeGzbSbTgmHi+sS6QAVXy2fvfdp/S AvmKuXgUComq/EOfW8UY4PU4wNA9VQ1mUVY8nqkY= Date: Fri, 19 Mar 2021 14:31:38 -0500 From: Tyler Hicks To: Pavel Tatashin Cc: jmorris@namei.org, sashal@kernel.org, pmladek@suse.com, ebiederm@xmission.com, keescook@chromium.org, anton@enomsg.org, ccross@android.com, tony.luck@intel.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: [PATCH v3 1/1] kexec: dump kmessage before machine_kexec Message-ID: <20210319193138.GA235401@sequoia> References: <20210319192326.146000-1-pasha.tatashin@soleen.com> <20210319192326.146000-2-pasha.tatashin@soleen.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210319192326.146000-2-pasha.tatashin@soleen.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-03-19 15:23:26, Pavel Tatashin wrote: > kmsg_dump(KMSG_DUMP_SHUTDOWN) is called before > machine_restart(), machine_halt(), machine_power_off(), the only one that > is missing is machine_kexec(). > > The dmesg output that it contains can be used to study the shutdown > performance of both kernel and systemd during kexec reboot. > > Here is example of dmesg data collected after kexec: > > root@dplat-cp22:~# cat /sys/fs/pstore/dmesg-ramoops-0 | tail > ... > <6>[ 70.914592] psci: CPU3 killed (polled 0 ms) > <5>[ 70.915705] CPU4: shutdown > <6>[ 70.916643] psci: CPU4 killed (polled 4 ms) > <5>[ 70.917715] CPU5: shutdown > <6>[ 70.918725] psci: CPU5 killed (polled 0 ms) > <5>[ 70.919704] CPU6: shutdown > <6>[ 70.920726] psci: CPU6 killed (polled 4 ms) > <5>[ 70.921642] CPU7: shutdown > <6>[ 70.922650] psci: CPU7 killed (polled 0 ms) > > Signed-off-by: Pavel Tatashin > Reviewed-by: Kees Cook > Reviewed-by: Petr Mladek > Reviewed-by: Bhupesh Sharma Reviewed-by: Tyler Hicks Tyler > Acked-by: Baoquan He > --- > kernel/kexec_core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > index a0b6780740c8..6ee4a1cf6e8e 100644 > --- a/kernel/kexec_core.c > +++ b/kernel/kexec_core.c > @@ -37,6 +37,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -1179,6 +1180,7 @@ int kernel_kexec(void) > machine_shutdown(); > } > > + kmsg_dump(KMSG_DUMP_SHUTDOWN); > machine_kexec(kexec_image); > > #ifdef CONFIG_KEXEC_JUMP > -- > 2.25.1 >