From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sai Prakash Ranjan Subject: Re: [PATCHv8 2/5] arm64: dts: qcom: msm8998: Add Coresight support Date: Thu, 18 Jul 2019 15:23:49 +0530 Message-ID: <2b08943b-3900-ceb5-15ac-28ef2bbad03e@codeaurora.org> References: <3b192063-f31f-b861-d913-61d737cecc57@arm.com> <4854b0f7-6a81-bc87-3e63-d2b7c68a44f6@codeaurora.org> <281e3548-af53-f9a7-b9e4-813b448ab078@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <281e3548-af53-f9a7-b9e4-813b448ab078@arm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Suzuki K Poulose , gregkh@linuxfoundation.org, mathieu.poirier@linaro.org, leo.yan@linaro.org, alexander.shishkin@linux.intel.com, mike.leach@linaro.org, robh+dt@kernel.org, bjorn.andersson@linaro.org, devicetree@vger.kernel.org, david.brown@linaro.org, mark.rutland@arm.com Cc: rnayak@codeaurora.org, vivek.gautam@codeaurora.org, sibis@codeaurora.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, marc.w.gonzalez@free.fr List-Id: devicetree@vger.kernel.org Hi, On 7/18/2019 3:07 PM, Suzuki K Poulose wrote: > > > Using the sysfs doesn't guarantee that the ETR actually uses SG mode, > unless > the buffer size selected is > 1M, which is why I am more interested in the > perf usage. Alternatively you may configure a larger buffer size (say, > 8MB) via: > > echo 0x800000 > /sys/bus/coresight/.../tmc_etr0/buffer_size > Yes, you had mentioned about setting buffer size > 1M in the same thread[1] and I had followed the same. [1] https://lkml.org/lkml/2019/1/18/311 > >> >> As said in one of the series initially [1], QCOM msm downstream kernels >> have been using scatter gather mode and we haven't seen any fatal issues. >> >> [1] https://patchwork.kernel.org/patch/10769535/ > > I haven't seen any test results there either. > You did not ask for it there ;) I do not have the test results handy now and those platforms. I will arrange for them and post some test results. Just to confirm, do you need some traces or just the buffer size and sink set? Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation