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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F24EC433EF for ; Wed, 22 Sep 2021 09:51:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 858C561100 for ; Wed, 22 Sep 2021 09:51:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234553AbhIVJwU (ORCPT ); Wed, 22 Sep 2021 05:52:20 -0400 Received: from foss.arm.com ([217.140.110.172]:45890 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234308AbhIVJwR (ORCPT ); Wed, 22 Sep 2021 05:52:17 -0400 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 6734A11B3; Wed, 22 Sep 2021 02:50:47 -0700 (PDT) Received: from [10.163.73.113] (unknown [10.163.73.113]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9A90C3F719; Wed, 22 Sep 2021 02:50:43 -0700 (PDT) Subject: Re: [PATCH v2 13/17] coresight: trbe: Add a helper to determine the minimum buffer size To: Suzuki K Poulose , linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, maz@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, james.morse@arm.com, leo.yan@linaro.org, mike.leach@linaro.org, mathieu.poirier@linaro.org, will@kernel.org, lcherian@marvell.com, coresight@lists.linaro.org References: <20210921134121.2423546-1-suzuki.poulose@arm.com> <20210921134121.2423546-14-suzuki.poulose@arm.com> From: Anshuman Khandual Message-ID: <586a307e-a51d-d176-b9f9-fc730278317e@arm.com> Date: Wed, 22 Sep 2021 15:21:49 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210921134121.2423546-14-suzuki.poulose@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/21/21 7:11 PM, Suzuki K Poulose wrote: > For the TRBE to operate, we need a minimum space available to collect > meaningful trace session. This is currently a few bytes, but we may need > to extend this for working around errata. So, abstract this into a helper > function. > > Cc: Anshuman Khandual > Cc: Mike Leach > Cc: Mathieu Poirier > Cc: Leo Yan > Signed-off-by: Suzuki K Poulose > --- > drivers/hwtracing/coresight/coresight-trbe.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c > index 797d978f9fa7..3373f4e2183b 100644 > --- a/drivers/hwtracing/coresight/coresight-trbe.c > +++ b/drivers/hwtracing/coresight/coresight-trbe.c > @@ -277,6 +277,11 @@ trbe_handle_to_cpudata(struct perf_output_handle *handle) > return buf->cpudata; > } > > +static u64 trbe_min_trace_buf_size(struct perf_output_handle *handle) > +{ > + return TRBE_TRACE_MIN_BUF_SIZE; > +} Assuming that struct perf_output_handle could provide all the required support for a variable minimum trace buffer length. Reviewed-by: Anshuman Khandual > + > /* > * TRBE Limit Calculation > * > @@ -447,7 +452,7 @@ static unsigned long trbe_normal_offset(struct perf_output_handle *handle) > * have space for a meaningful run, we rather pad it > * and start fresh. > */ > - if (limit && (limit - head < TRBE_TRACE_MIN_BUF_SIZE)) { > + if (limit && ((limit - head) < trbe_min_trace_buf_size(handle))) { > trbe_pad_buf(handle, limit - head); > limit = __trbe_normal_offset(handle); > } >