From patchwork Thu Oct 14 22:31:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 12559531 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 C9265C433EF for ; Thu, 14 Oct 2021 22:34:25 +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 8CC2760E53 for ; Thu, 14 Oct 2021 22:34:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8CC2760E53 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com 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:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MCkXqTGARdKUXu/2P/P199Xeg0GblXgt0MCQQ29+jog=; b=aqZjXasDLqFHI0 UogrlSdGkHfhzNtqOaJ5d0tB2ujZkVp1GeQRdA5S2SncDK5lGKk8K4XWKA1tqZqUWTZJkvK3EYAzr ebEG5C5ILhOAmqLS/jjGEvLLriz8+C7gJPP/OuCuK2l0j2UxDadh7MZCGgoJeuokuyzccyVPkakRD aSpXyNItnAtnSub2jxu3TDsfqmU+foQks2+1peFhYSpfPSyzy7VKItKvoBENfrs0HTZHqLRl5uSCM w70tbkZxmraxrUykCry1vp4SpHt/vIFGWobZYZYlCNeyyZK3Q8Ticjhank5rwblVP+D6jcoYqk61G Y4oEpgL3K0uMRXyK3Hjw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mb9HZ-004Vd1-F4; Thu, 14 Oct 2021 22:33:01 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mb9GM-004V7Y-9P for linux-arm-kernel@lists.infradead.org; Thu, 14 Oct 2021 22:31:47 +0000 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 A06BD152F; Thu, 14 Oct 2021 15:31:44 -0700 (PDT) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 364483F694; Thu, 14 Oct 2021 15:31:43 -0700 (PDT) From: Suzuki K Poulose To: will@kernel.org, mathieu.poirier@linaro.org Cc: catalin.marinas@arm.com, anshuman.khandual@arm.com, mike.leach@linaro.org, leo.yan@linaro.org, maz@kernel.org, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Suzuki K Poulose Subject: [PATCH v5 05/15] coresight: trbe: Add a helper to calculate the trace generated Date: Thu, 14 Oct 2021 23:31:15 +0100 Message-Id: <20211014223125.2605031-6-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20211014223125.2605031-1-suzuki.poulose@arm.com> References: <20211014223125.2605031-1-suzuki.poulose@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211014_153146_442511_2E58B3C1 X-CRM114-Status: GOOD ( 14.80 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org We collect the trace from the TRBE on FILL event from IRQ context and via update_buffer(), when the event is stopped. Let us consolidate how we calculate the trace generated into a helper. Cc: Mathieu Poirier Cc: Mike Leach Cc: Leo Yan Reviewed-by: Anshuman Khandual Signed-off-by: Suzuki K Poulose --- Changes since v2: - Fix code style issues - Read base pointer directly now. Switch to using cached value of the base of the ring buffer, when this changes. --- drivers/hwtracing/coresight/coresight-trbe.c | 47 ++++++++++++-------- 1 file changed, 29 insertions(+), 18 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c index 2825ccb0cf39..5902ef41bfb8 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.c +++ b/drivers/hwtracing/coresight/coresight-trbe.c @@ -499,6 +499,29 @@ static enum trbe_fault_action trbe_get_fault_act(u64 trbsr) return TRBE_FAULT_ACT_SPURIOUS; } +static unsigned long trbe_get_trace_size(struct perf_output_handle *handle, + struct trbe_buf *buf, bool wrap) +{ + u64 write; + u64 start_off, end_off; + + /* + * If the TRBE has wrapped around the write pointer has + * wrapped and should be treated as limit. + */ + if (wrap) + write = get_trbe_limit_pointer(); + else + write = get_trbe_write_pointer(); + + end_off = write - get_trbe_base_pointer(); + start_off = PERF_IDX2OFF(handle->head, buf); + + if (WARN_ON_ONCE(end_off < start_off)) + return 0; + return (end_off - start_off); +} + static void *arm_trbe_alloc_buffer(struct coresight_device *csdev, struct perf_event *event, void **pages, int nr_pages, bool snapshot) @@ -560,9 +583,9 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, struct trbe_cpudata *cpudata = dev_get_drvdata(&csdev->dev); struct trbe_buf *buf = config; enum trbe_fault_action act; - unsigned long size, offset; - unsigned long write, base, status; + unsigned long size, status; unsigned long flags; + bool wrap = false; WARN_ON(buf->cpudata != cpudata); WARN_ON(cpudata->cpu != smp_processor_id()); @@ -602,8 +625,6 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, * handle gets freed in etm_event_stop(). */ trbe_drain_and_disable_local(); - write = get_trbe_write_pointer(); - base = get_trbe_base_pointer(); /* Check if there is a pending interrupt and handle it here */ status = read_sysreg_s(SYS_TRBSR_EL1); @@ -627,20 +648,11 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, goto done; } - /* - * Otherwise, the buffer is full and the write pointer - * has reached base. Adjust this back to the Limit pointer - * for correct size. Also, mark the buffer truncated. - */ - write = get_trbe_limit_pointer(); trbe_report_wrap_event(handle); + wrap = true; } - offset = write - base; - if (WARN_ON_ONCE(offset < PERF_IDX2OFF(handle->head, buf))) - size = 0; - else - size = offset - PERF_IDX2OFF(handle->head, buf); + size = trbe_get_trace_size(handle, buf, wrap); done: local_irq_restore(flags); @@ -721,11 +733,10 @@ static int trbe_handle_overflow(struct perf_output_handle *handle) { struct perf_event *event = handle->event; struct trbe_buf *buf = etm_perf_sink_config(handle); - unsigned long offset, size; + unsigned long size; struct etm_event_data *event_data; - offset = get_trbe_limit_pointer() - get_trbe_base_pointer(); - size = offset - PERF_IDX2OFF(handle->head, buf); + size = trbe_get_trace_size(handle, buf, true); if (buf->snapshot) handle->head += size;