From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 015433F870C for ; Thu, 16 Jul 2026 19:24:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784229880; cv=none; b=iDRk1KlA3utjdjd4Q+ybsoG57vWXRNb2FE+emjrPFv9OM8HqNaQwC/0Ts9BS6R9sWIzOPBC4vybmmQB6omJXXz95tyjWbztoo1KPHa2skXfs6ANO98Qne3U6b4uUm611qiIAU9VCHG9DSLMt0TcowWkumxvsvPznGGdF5DMj8dQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784229880; c=relaxed/simple; bh=tLfQE+sovK0Rmbekq3ZnIEFvDEsmscpFTa2E4Nbf7os=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rrWvoIas5v1rKVnoWCct7eoeffxRCW8fwOCtWuEZWlGk0ymiBMjf+gijcJwCydnQn43BkV5iA94+OZ2Xy6XrTyjdldLlcct6aWK6qoFpnpyMB0gfiYex8oO8fI89JtEQFZAVSLOtD8B0U7j86AoDXyjUuZlqdIJGWhDncAZ5Ug8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=loOZX1A8; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="loOZX1A8" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 81BB61476; Thu, 16 Jul 2026 12:24:32 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.2.213.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3EDDA3F66F; Thu, 16 Jul 2026 12:24:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1784229876; bh=tLfQE+sovK0Rmbekq3ZnIEFvDEsmscpFTa2E4Nbf7os=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=loOZX1A8xLHWRCLnA/im6N5qEKtTapWA61zE2fE7IATydD7VG8XSL8p72dpXwbJMN prgKHdss8m33hnU8INM7lAzTJBbV5QCw53TvyJKjCjdGwIQgsGH2aKXr0DA+Y69i13 3/NRFOB61fufzftfVJodf05N70kpmV2j+cvjAiik= Date: Thu, 16 Jul 2026 20:24:32 +0100 From: Yeoreum Yun To: Suzuki K Poulose Cc: Yeoreum Yun , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, mike.leach@arm.com, james.clark@linaro.org, alexander.shishkin@linux.intel.com, leo.yan@arm.com, jie.gan@oss.qualcomm.com Subject: Re: [PATCH v8 00/13] fix several inconsistencies with sysfs configuration in etmX Message-ID: References: <20260629090007.1718746-1-yeoreum.yun@arm.com> <6ec5e456-fdf9-4953-9a0f-6231b48df07a@arm.com> 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: <6ec5e456-fdf9-4953-9a0f-6231b48df07a@arm.com> On Thu, Jul 16, 2026 at 01:48:15PM +0100, Suzuki K Poulose wrote: > On 29/06/2026 09:59, Yeoreum Yun wrote: > > The current ETMx configuration via sysfs can lead to the following > > inconsistencies: > > > > - If a configuration is modified via sysfs while a perf session is > > active, the running configuration may differ between before > > a sched-out and after a subsequent sched-in. > > > > - If a perf session and sysfs session tries to enable concurrently, > > configuration from configfs could be corrupted (etm4). > > > > - There is chance to corrupt drvdata->config if perf session tries > > to enabled among handling cscfg_csdev_disable_active_config() > > in etm4_disable_sysfs() (etm4). > > > > To resolve these inconsistencies, the configuration should be separated into: > > > > - active_config, which is applied configuration for the current session > > - config, which stores the settings configured via sysfs. > > > > and apply configuration from configfs after taking a mode. > > > > Also, This patch set includes some small fixes: > > - missing trace id release in etm4x. > > - underflow issue for nrseqstate. > > - wrong check in etm4x_sspcicrn_present(). > > - missing call of cscfg_csdev_disable_active_config() > > > > This patch based on coresight tree's next > > > Please could you move all the "Fixes" to the top of the series, that way > it is cleaner to backport for the stable kernels Okay. but the fix which based on the cleanup wouldn't be top of it. I'll deploy below patches first: coresight: etm3x: change drvdata->spinlock type to raw_spin_lock_t coresight: etm4x: fix leaked trace id coresight: etm4x: fix underflow for usage of (nrseqstate - 1) coresight: etm4x: fix wrong check of etm4x_sspcicrn_present() > > I have some minor comments, please could you address them. Otherwise, > looks good to me. Thanks for the cleanup Thanks for your review! > > > > > > Patch History > > ============= > > from v7 to v8: > > - accept @Leo Yan' suggestion to handle error. > > - small minor fixes following @Suzuki' suggestion. > > - https://lore.kernel.org/all/20260519154812.254884-1-yeoreum.yun@arm.com/ > > > > from v6 to v7: > > - rebase on coresight/next > > - add ETM_MAX_SEQ_TRANSITIONS define > > - remove redundant patch relavent cpu-hotplug as coresight-pm patch > > merged. > > - https://lore.kernel.org/all/20260422132203.977549-1-yeoreum.yun@arm.com/ > > > > from v5 to v6: > > - fix missing of calling cscfg_csdev_disable_active_config() > > - add rb & fixes tags. > > - add ss_status field in etm4x_drvdata to expose STATUS and PENDING bits. > > - https://lore.kernel.org/all/20260415165528.3369607-1-yeoreum.yun@arm.com/ > > > > from v4 to v5: > > - add rb-tag. > > - fix underflow issue for nrseqstate. > > - fix wrong check in etm4_sspcicrn_present(). > > - remove redundant fields on etmv4_save_state. > > - rename caps->ss_status to ss_cmp. > > - fix wrong location of etm4_release_trace_id. > > - https://lore.kernel.org/all/20260413142003.3549310-1-yeoreum.yun@arm.com/ > > > > from v3 to v4: > > - change etm_drvdata->spinlock type to raw_spin_lock_t > > - remove redundant call etmX_enable_hw() with starting_cpu() callsback. > > - fix missing trace id release. > > - add missing docs. > > - https://lore.kernel.org/all/20260412175506.412301-1-yeoreum.yun@arm.com/ > > > > from v2 to v3: > > - fix build error for etm3x. > > - fix checkpatch warning. > > - https://lore.kernel.org/all/20260410074310.2693385-1-yeoreum.yun@arm.com/ > > > > from v1 to v2 > > - rebased to v7.0-rc7. > > - introduce etmX_caps structure to save etmX's capabilities. > > - remove ss_status from etmv4_config. > > - modify active_config after taking a mode (perf/sysfs). > > - https://lore.kernel.org/all/20260317181705.2456271-1-yeoreum.yun@arm.com/ > > > > > > Yeoreum Yun (13): > > coresight: etm4x: fix wrong check of etm4x_sspcicrn_present() > > coresight: etm4x: fix underflow for usage of (nrseqstate - 1) > > coresight: etm4x: introduce struct etm4_caps > > coresight: etm4x: exclude ss_status from drvdata->config > > coresight: etm4x: remove s_ex_level from config > > coresight: etm4x: remove redundant fields in etmv4_save_state > > coresight: etm4x: fix leaked trace id > > coresight: etm4x: fix inconsistencies with sysfs configuration > > coresight: etm4x: missing cscfg_csdev_disable_active_config() in perf > > enable > > coresight: etm3x: change drvdata->spinlock type to raw_spin_lock_t > > coresight: etm3x: introduce struct etm_caps > > coresight: etm3x: fix inconsistencies with sysfs configuration > > coresight: etm3x: remove redundant cpu online check on > > etm_enable_sysfs() > > > > drivers/hwtracing/coresight/coresight-etm.h | 46 +- > > .../coresight/coresight-etm3x-core.c | 96 ++-- > > .../coresight/coresight-etm3x-sysfs.c | 159 +++--- > > .../hwtracing/coresight/coresight-etm4x-cfg.c | 5 +- > > .../coresight/coresight-etm4x-core.c | 454 ++++++++++-------- > > .../coresight/coresight-etm4x-sysfs.c | 204 ++++---- > > drivers/hwtracing/coresight/coresight-etm4x.h | 202 ++++---- > > 7 files changed, 639 insertions(+), 527 deletions(-) > > > -- Sincerely, Yeoreum Yun