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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E56EC433EF for ; Tue, 9 Nov 2021 15:50:58 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C7DE361186 for ; Tue, 9 Nov 2021 15:50:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C7DE361186 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MYeTu2IVxuyBPeS5DIPOMeMf+hvZlIE65/2ELyDAXLw=; b=NrYxYxwEK2R6Tq p5Torw0fGlMQuvnks6dr3FOx81CzSDi2qDilNLmXkNUSp2Y035xv715Xh5eveCva6OikH7Kt1CYuA LJ8CCjNcVWMpgS972HArvsKAZG9vuf7ROPbq+fPYtRZ4/gI48iHmhuSLB7pduHVqkkaE6w82cwDKK wKLu5BgTesJZ0JAOdU+QUXwMErP9BNG4TqzfcRZ1No1BN3jjcbkhfgLU2YR8kvUvsTwk5UEJeTYnD MR38XRhZGAWlQy3OLueWMs9JR6qCwAqfB6UsIg4cNu79FIiE2KF7opHjH1MUTDBmD9CxKlwncoZ4R +erVi6zn4jlwgCpMnoSw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mkTNc-002brM-NO; Tue, 09 Nov 2021 15:49:48 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mkTNY-002bqb-Ss for linux-arm-kernel@lists.infradead.org; Tue, 09 Nov 2021 15:49:46 +0000 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6EFA961186; Tue, 9 Nov 2021 15:49:43 +0000 (UTC) Date: Tue, 9 Nov 2021 10:49:41 -0500 From: Steven Rostedt To: Sai Prakash Ranjan Cc: Will Deacon , Catalin Marinas , , Marc Zyngier , , , , , , , , Subject: Re: [PATCHv3 3/3] dynamic_debug: Add a flag for dynamic event tracing Message-ID: <20211109104941.2d50eafc@gandalf.local.home> In-Reply-To: <3706af20bc64a320ff8f3ff8950738b988f4bdf5.1636452784.git.quic_saipraka@quicinc.com> References: <3706af20bc64a320ff8f3ff8950738b988f4bdf5.1636452784.git.quic_saipraka@quicinc.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211109_074944_979974_5CB0F4E4 X-CRM114-Status: GOOD ( 16.53 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, 9 Nov 2021 17:38:21 +0530 Sai Prakash Ranjan wrote: > Debugging a specific driver or subsystem can be a lot easier if we can > trace events specific to that driver or subsystem. This type of > filtering can be achieved using existing dynamic debug library which > provides a way to filter based on files, functions and modules. > > Using this, provide an additional flag 'e' to filter event tracing to > specified input. > > For example, tracing all MMIO read/write can be overwhelming and of no > use when debugging a specific driver or a subsystem. So switch to > dynamic event tracing for register accesses. > > Example: Tracing register accesses for all drivers in drivers/soc/qcom/* > and the trace output is given below: > > # dyndbg="file drivers/soc/qcom/* +e" trace_event=rwmmio > or > # echo "file drivers/soc/qcom/* +e" > /sys/kernel/debug/dynamic_debug/control > # cat /sys/kernel/debug/tracing/trace FYI, it's best to use /sys/kernel/tracing, as the debug/tracing is only there for backward compatibility. > rwmmio_read: rpmh_rsc_probe+0x35c/0x410 readl addr=0xffff80001071000c > rwmmio_read: rpmh_rsc_probe+0x3d0/0x410 readl addr=0xffff800010710004 > rwmmio_write: rpmh_rsc_probe+0x3b0/0x410 writel addr=0xffff800010710d00 val=0x3 > rwmmio_write: write_tcs_cmd+0x6c/0x78 writel addr=0xffff800010710d30 val=0x10108 I'd much rather have a module name or something attached to the event that ca be filtered on via the trace event filters, than having it determined by some side effect done in another directory. -- Steve _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel