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 AA1AEC77B78 for ; Thu, 4 May 2023 15:02:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230017AbjEDPCs (ORCPT ); Thu, 4 May 2023 11:02:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbjEDPCZ (ORCPT ); Thu, 4 May 2023 11:02:25 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80EB740F2; Thu, 4 May 2023 08:01:51 -0700 (PDT) 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=J9lcuz0U78xiVesYVTRvv8JVCKEh3ZCKl4adkGMz7q8=; b=A3tkeyDTbxVkt6nED1FtXwR7g1 zZTYBRWgzTAAp9BZC1qV19RLdqwHus5AQdNJk4QDytJqfu0d3fusfZd6tmpLHnup1qMzIq1UrlO3r jA6uWCDheYZh0N1afd4u6dydMh83H4G0C7c0LyDOr1Qr40sZHIjHkJkow0b886Qh4GbbmeqrET+yC BKxh99Ux1Z2HW5bHnTcfrJMEd9lz//bcPqHa45Sgaoqw9q3Kc56na7ZITUjHj87fDXB5OTA+CPbNJ Z7SX69si5EG372gxmdBynOePTt2mscU8e3Oeylz4MD/j1jNX9ZkD6PiiSxjMnfY1tl6QpLBO6zlfn g1uP3SFA==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1puaSJ-00AhL6-Rb; Thu, 04 May 2023 15:01:16 +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 00C7B3003CF; Thu, 4 May 2023 17:01:13 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D677D2407F43F; Thu, 4 May 2023 17:01:13 +0200 (CEST) Date: Thu, 4 May 2023 17:01:13 +0200 From: Peter Zijlstra To: Valentin Schneider Cc: Leonardo =?iso-8859-1?Q?Br=E1s?= , Steven Rostedt , Masami Hiramatsu , Thomas Gleixner , Yury Norov , "Paul E. McKenney" , Sebastian Andrzej Siewior , Nadav Amit , Zhen Lei , Chen Zhongjin , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Marcelo Tosatti , Daniel Bristot de Oliveira Subject: Re: [RFC PATCH 1/1] smp: Add tracepoints for functions called with smp_call_function*() Message-ID: <20230504150113.GB1744142@hirez.programming.kicks-ass.net> References: <20230406075718.68672-1-leobras@redhat.com> <20230406095519.GG386572@hirez.programming.kicks-ass.net> <20230503145900.GC1689514@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 04, 2023 at 12:59:41PM +0100, Valentin Schneider wrote: > With that said, I suppose this could still be helpful for e.g. osnoise to > hook into and point the finger at which CPU/context sent the problematic > IPI. Or more generally, as Leonardo suggested, to measure CSD IPI delivery > times. > > One thing though is that trace_ipi_send_cpu*() is not used solely for > CSD's, cf. irq_work_raise() or smp_send_reschedule(). We might want to > split that into e.g. trace_csd_queue_cpu*() + trace_ipi_send*(). > > Something like so... > Yeah, looks about right I suppose.. it generates more events, but given we need the csd that's inevitable.