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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53AFCC433EF for ; Tue, 1 Mar 2022 09:05:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233644AbiCAJG1 (ORCPT ); Tue, 1 Mar 2022 04:06:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230385AbiCAJGT (ORCPT ); Tue, 1 Mar 2022 04:06:19 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2C9E88B1F; Tue, 1 Mar 2022 01:05:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=ypFVgiobg8wO+A66SFG5Fx9R9ZoG7oPUgj1Wyrv8P+k=; b=jlDbn0r2/yAl/JGPsa9Fo7fAwx 648B6op6eIuFS8obnBy+R/ZPxwZ5Cu+uZysk57Y8WKbeAckr+bgHNRRaywV8n4fkvJleTzx1rRKMm zgS1q8SRIJXg46/GFkJU8K6aEm/SGXxOvXDkPu+DUNOL4Kbw23hMVjOeY5JzluH2vMC/pWhiB4j+a 61kzZy6CsB2Ph/vPFDrmURMSiMRjDeL7b5PXDy5dNPfQ2u6T3Lgk6g2521wMTM7oX5Z3b87S4jzKg Pd7nq9NeTg+8+0mx9OpVX5xxZUPUItgWqOnZJEsSWURwEjuvYT1WV8otutSpRiGgtQ2lYH1iaXNMV S6oOgeEQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nOyRW-009QMM-0l; Tue, 01 Mar 2022 09:05:14 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id EBBFD30018E; Tue, 1 Mar 2022 10:05:12 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id DBECD2024C933; Tue, 1 Mar 2022 10:05:12 +0100 (CET) Date: Tue, 1 Mar 2022 10:05:12 +0100 From: Peter Zijlstra To: Namhyung Kim Cc: Ingo Molnar , Will Deacon , Waiman Long , Boqun Feng , LKML , Thomas Gleixner , Steven Rostedt , Mathieu Desnoyers , Byungchul Park , "Paul E. McKenney" , Arnd Bergmann , linux-arch@vger.kernel.org, bpf@vger.kernel.org, Radoslaw Burny Subject: Re: [PATCH 3/4] locking/mutex: Pass proper call-site ip Message-ID: References: <20220301010412.431299-1-namhyung@kernel.org> <20220301010412.431299-4-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220301010412.431299-4-namhyung@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 28, 2022 at 05:04:11PM -0800, Namhyung Kim wrote: > The __mutex_lock_slowpath() and friends are declared as noinline and > _RET_IP_ returns its caller as mutex_lock which is not meaningful. > Pass the ip from mutex_lock() to have actual caller info in the trace. Blergh, can't you do a very limited unwind when you do the tracing instead? 3 or 4 levels should be plenty fast and sufficient.