From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 18CA0128820 for ; Tue, 16 Apr 2024 11:18:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713266282; cv=none; b=QHdJLMj+hrQmt29lCMPtE+dnzEAp8EBXGSsiDdXXyYz9tDADHkzY4EuSn8GIQBiy16k2ksg0dDh7j3f1MaKJq43O3WcMBIseWOaUIyRYHhKrcqkBQp+LXqsgVIagqQ3vLjoe3a3EdpIVzq/5ARSgI9jDL5+kozQRUxQ/AS73V3k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713266282; c=relaxed/simple; bh=duFrP0x3+qNKG3tHLlle3sc6z5Hv/xwPHlK3OcIV2F4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=bL8fBCT13a5+dbv/XfoEZSjIAxWhYvKeuqrNDKBQ+3FQVaSOXLuWDf85Jg+vPeDPKScZuEE1YIZpZ7SfWISezeyLUZ8yZ8inkg1cQpLWmiY7kvO+hau0tr1YYIGAF2xM6pA4w6FMVckLuIFAqONSXdRGjsRR8DxNu9iVUnflIoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=MnC69Yz+; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="MnC69Yz+" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=duFrP0x3+qNKG3tHLlle3sc6z5Hv/xwPHlK3OcIV2F4=; b=MnC69Yz+ffXS32fDmSHhEEtzGi uWCzvG/izsTyQ9o6+MJEEC3oewhucbyLwrVCZB3K3rAtGXzpPpG1j7vHmZDWOJfcil6bw2CxOU08J u6mCZ588PSMIUAmtbkj82TizUTUJnzKJPymi/He1eHQTcqQspgM8ZfFhsvc8x5j7faZZuHqVniC85 iG/nMiO+JHu8pJ66akDNPt1mDBQhR9dVCProDP1aMrM/ll7enCO7rJsg+LPAQ/UhUyDcN3BYae/5+ v4DW1kvoGx8Od97MXsm6OJyWf+J3+ax1fhBw4jzU5GX7S+UQpvrYxJO3lb6vVl/wRlzIbLQvzHwyj GFVTJbeQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1rwgov-0000000B2oH-2MEV; Tue, 16 Apr 2024 11:17:52 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 38E5C30040C; Tue, 16 Apr 2024 13:17:49 +0200 (CEST) Date: Tue, 16 Apr 2024 13:17:49 +0200 From: Peter Zijlstra To: John Ogness Cc: Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Ingo Molnar , Will Deacon , Waiman Long , Boqun Feng Subject: Re: [PATCH printk v4 27/27] lockdep: Mark emergency sections in lockdep splats Message-ID: <20240416111749.GM40213@noisy.programming.kicks-ass.net> References: <20240402221129.2613843-1-john.ogness@linutronix.de> <20240402221129.2613843-28-john.ogness@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240402221129.2613843-28-john.ogness@linutronix.de> On Wed, Apr 03, 2024 at 12:17:29AM +0206, John Ogness wrote: > Mark emergency sections wherever multiple lines of > lock debugging output are generated. In an emergency > section the CPU will not perform console output for the > printk() calls. Instead, a flushing of the console > output is triggered when exiting the emergency section. > This allows the full message block to be stored as > quickly as possible in the ringbuffer. I am confused, when in emergency I want the thing to dump everything to the atomic thing asap. Storing it all up runs the risk of never getting to the 'complete' point because we're dead.