From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752335AbeBHVHW (ORCPT ); Thu, 8 Feb 2018 16:07:22 -0500 Received: from foss.arm.com ([217.140.101.70]:40480 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752046AbeBHVHV (ORCPT ); Thu, 8 Feb 2018 16:07:21 -0500 Date: Thu, 8 Feb 2018 15:07:18 -0600 From: Kim Phillips To: Randy Dunlap Cc: Robin Murphy , Mathieu Poirier , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose Subject: Re: [PATCH] coresight replicator: set default y after Kconfig rename Message-Id: <20180208150718.36e72e4c3e96e3f4357e5c08@arm.com> In-Reply-To: <8cdc4fe6-faf6-412e-51af-a65d576ecc3f@infradead.org> References: <20180207150351.ce930e929bc0d7f6cfb1aa56@arm.com> <4ed2bf14-206a-20c6-40a6-3ab9a2ec07b4@arm.com> <20180208132354.5d66ab91234bd7c7d971c1b1@arm.com> <8cdc4fe6-faf6-412e-51af-a65d576ecc3f@infradead.org> Organization: Arm X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 8 Feb 2018 11:53:44 -0800 Randy Dunlap wrote: > On 02/08/2018 11:23 AM, Kim Phillips wrote: > > On Thu, 8 Feb 2018 16:13:16 +0000 > > Robin Murphy wrote: > > > >> On 07/02/18 21:03, Kim Phillips wrote: > >>> Commit 1c8859848dbb ("coresight replicator: Cleanup programmable > >>> replicator naming") changed the Kconfig symbol name from > >>> QCOM_REPLICATOR, which, whilst not in the single arm64 defconfig, > >>> was being set in my juno build script, which left the new symbol unset, > >>> causing the following unexpected grief: > >>> > >>> # ./perf record -vvv -C 0 -e cs_etm/@20070000.etr/ --per-thread true > >>> .... > >>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5 > >>> mmap size 528384B > >>> AUX area mmap length 4194304 > >>> perf event ring buffer mmapped per cpu > >>> failed to mmap AUX area > >>> failed to mmap with 12 (Cannot allocate memory) > >>> > >>> Make it default y to help not surprise unsuspecting users. > >> > >> How many users are there relying on your Juno build script? :P > > > > This shouldn't be that uncommon for coresight users: > > > > make defconfig > > scripts/config -e CONFIG_CORESIGHT > > scripts/config -e CONFIG_CORESIGHT_LINK_AND_SINK_TMC > > scripts/config -e CONFIG_CORESIGHT_SINK_TPIU > > scripts/config -e CONFIG_CORESIGHT_SINK_ETBV10 > > scripts/config -e CONFIG_CORESIGHT_LINKS_AND_SINKS > > scripts/config -e CONFIG_CORESIGHT_SOURCE_ETM3X > > scripts/config -e CONFIG_CORESIGHT_SOURCE_ETM4X > > #scripts/config -e CONFIG_CORESIGHT_QCOM_REPLICATOR > > scripts/config -e CONFIG_CORESIGHT_DYNAMIC_REPLICATOR > > scripts/config -e CONFIG_CORESIGHT_STM > > scripts/config -e CONFIG_CORESIGHT_CPU_DEBUG > > > > FWIW, Mathieu - who helped me track the cannot allocate memory problem > > down to this config symbol - has also benn caught by this issue. > > > >>> Fixes: 1c8859848dbb ("coresight replicator: Cleanup programmable replicator naming") > >> > >> Before that commit, CORESIGHT_QCOM_REPLICATOR was not "default y", nor > >> selected by any in-tree configs, so whatever the problem may be this is > >> clearly not the correct fix. > > > > Well, there's only one defconfig for arm64. I don't know why it > > doesn't set CORESIGHT, but you're right, this is taking the build fix > > one step further to facilitate user coresight configuration. I can > > change the patch to make the change to the arm64 defconfig, but I still > > believe CORESIGHT_DYNAMIC_REPLICATOR should be default=y, and the > > defconfig just set CORESIGHT. > > > >>> Cc: Mathieu Poirier > >>> Cc: Suzuki K Poulose > >>> Signed-off-by: Kim Phillips > >>> --- > >>> drivers/hwtracing/coresight/Kconfig | 1 + > >>> 1 file changed, 1 insertion(+) > >>> > >>> diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig > >>> index ef9cb3c164e1..b94bbd95efa6 100644 > >>> --- a/drivers/hwtracing/coresight/Kconfig > >>> +++ b/drivers/hwtracing/coresight/Kconfig > >>> @@ -73,6 +73,7 @@ config CORESIGHT_SOURCE_ETM4X > >>> config CORESIGHT_DYNAMIC_REPLICATOR > >>> bool "CoreSight Programmable Replicator driver" > >>> depends on CORESIGHT_LINKS_AND_SINKS > >>> + default y > >> > >> CORESIGHT_LINKS_AND_SINKS is "default n" (as indeed is CORESIGHT), and > >> not selected by any defconfigs, so in general this doesn't really help > >> anyway. > > > > Yeah, CORESIGHT_LINKS_AND_SINKS should probably be default y too. > > Are they required for system operation? If not, they should not default to y. They're not required for general purpose system operation: they're protected by an if CORESIGHT. All the other CORESIGHT symbols select CORESIGHT_LINKS_AND_SINKS except CORESIGHT_CPU_DEBUG, which doesn't need to be protected by the if CORESIGHT. > and if they are required, it seems odd that they are in drivers/hwtracing/. Right, they are required for tracing using the Coresight subsystem, not general purpose system operation, so they can be 'default y' under 'if CORESIGHT' protection. Kim