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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 62AD9C4363D for ; Thu, 24 Sep 2020 18:08:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16C192399A for ; Thu, 24 Sep 2020 18:08:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="BFv13BBw"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="FyjIgl0r" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728687AbgIXSIc (ORCPT ); Thu, 24 Sep 2020 14:08:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727753AbgIXSIc (ORCPT ); Thu, 24 Sep 2020 14:08:32 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B941C0613CE for ; Thu, 24 Sep 2020 11:08:32 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600970910; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=7Bw5S+6KuIUsf1Ic4pM97Qi2nlRcZRP5Ar9fFDTLLUw=; b=BFv13BBwZgcf3j3gzcZuOliSN8tZcl0i/3dGzy5msoV6KtAaVM1UaERRetVK3NJaHj/5xk UIO65CxI9LstgnSToCBpHWSmRN5EbRbO5g8NKQCPFX+QnEgqiWGGWkPYWilX0+AjyEUbHq loo+/XDnwPc4bBteAQPZT6IZCGA6UKBEyt4azsnpKrLgYAwOVhdT+x7DhevzuiE50fPh/S Rbd0PHY+fAFQV7Jop2Ji0MLy07aMAqo5Y8jkV4in2rUObveERnjBm+Wf5hpu84JMGojsr0 Mka2am2irirRyj+a86syQ7G2qQ8nQxXPv7h05GpofGotZ28FiD/9P1tM0H7xag== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600970910; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=7Bw5S+6KuIUsf1Ic4pM97Qi2nlRcZRP5Ar9fFDTLLUw=; b=FyjIgl0rAl+mfyJCmXnGuCr/m1OxqqIiW9SGRGkrMzi5Arq7DjIq7YyFH81d135W6Tf9YP GcyvhfigZHF+9OBA== To: Prasad Sodagudi , rostedt@goodmis.org, pmladek@suse.com, sergey.senozhatsky@gmail.com, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, tkjos@google.com, Prasad Sodagudi Subject: Re: [PATCH 1/2] genirq/cpuhotplug: Reduce logging level for couple of prints In-Reply-To: <1600906112-126722-1-git-send-email-psodagud@codeaurora.org> References: <1600906112-126722-1-git-send-email-psodagud@codeaurora.org> Date: Thu, 24 Sep 2020 20:08:30 +0200 Message-ID: <87zh5f6o9t.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 23 2020 at 17:08, Prasad Sodagudi wrote: > During the cpu hot plug stress testing, couple of messages > continuous flooding on to the console is causing timers > migration delay. Delayed time migrations from hot plugging > core is causing device instability with watchdog. So reduce > log level for couple of prints in cpu hot plug flow. This is fixing the wrong end, really. Timer migration can be delayed by other means as well. The real problem is that the migration happens _after_ the CPU is completely dead and the hotplug control thread is not guaranteed to reach the timer migration state before timers are overdue at all. There is a bunch of related problems, e.g. the interrupt migration mechanism kicks in late as well. I'm not against changing the log level per se, but the justification for doing so is just bogus. The more obvious question is whether these printks are useful at all other than at the pr_debug() level. Thanks, tglx