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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 CD3E7C4360F for ; Thu, 4 Apr 2019 03:36:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A33F2171F for ; Thu, 4 Apr 2019 03:36:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="uWXgpbR5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728067AbfDDDgW (ORCPT ); Wed, 3 Apr 2019 23:36:22 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:33114 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726791AbfDDDgS (ORCPT ); Wed, 3 Apr 2019 23:36:18 -0400 Received: by mail-pl1-f195.google.com with SMTP id t16so451273plo.0 for ; Wed, 03 Apr 2019 20:36:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Rp82OG+X/1qzhxgu7Opyhu1qYPCsjQeQJx+i+wMOyCE=; b=uWXgpbR5YVsdh1tkDK3c5M04exY7enShlsPHkKIwIqAg0jQLEPod7MxEbk+H/2YFcz ewWG019xQA/Lf3qtj7FErkvgro8gloYUwKTnLt3zJBa0YkZg3/yTQKVP43a5ex9/trTj JBzE92biGwlCxAdYA4Hhd7E085uqcUxOGhHqXVKLUEl4vxT4Z8zQnRPzaTaP2iyonlxt YDL9xYwgQat52IAFAuTHfzAHEVwNW5QgWQSFHN5IkO1BrKu5PwOwmDA5YIz/O6wOhF8V BMusCcGqe0BdXZ24kQU/tmzfO11fxxnV68luRiypOvVdge7qwRy0Q64yE0uTA+KjOMcO L8Hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Rp82OG+X/1qzhxgu7Opyhu1qYPCsjQeQJx+i+wMOyCE=; b=pwNCXr7FGGDNp+3k7pm1ESOZp0TnVgeahB0TBx4YN1ykFrHh17bJoV8B/LFSeG/9k/ 1t/HD0+McQGJv6Y7CWA4gbau2JmZNQCr2VsBCQsUlXGXBktPYZ/AireMHSIaKlhxHZus E+rmHLkTWcYzmbj7rRIBuqjNmc7V5DN+lwBqh8XGYokOtT1NyaTn1IL2yr7+42RHHHPV hR03bFJfujczGD8TXeqg6MxyB3XRx6WW9Wz3c2rRIdq4glR9cVIvLgg0tf3kiwfjLiHd YjP3LiQy3S/o+6PWj/P6nxjwMviQwqL1oUsHnrezoKXqE8ESuOUYv3mU+oEaSboOqmjE ZDLg== X-Gm-Message-State: APjAAAX1zTwX6vMbxMQOLlezdOowl3E9N5ZH4dr+i6JYc0uLGhvOn9J4 DB7W/agnuR0naZVKypep/ldd4A== X-Google-Smtp-Source: APXvYqxnprVmjjSF2tnUy4v7IbtEfubrPIrN37Y9gmUqDHLVytF4Jl14psXToYqcyqwcjS/j3syzww== X-Received: by 2002:a17:902:5a2:: with SMTP id f31mr3721169plf.119.1554348977964; Wed, 03 Apr 2019 20:36:17 -0700 (PDT) Received: from xps15.imgcgcw.net ([147.50.13.10]) by smtp.gmail.com with ESMTPSA id u5sm12212780pfm.121.2019.04.03.20.36.14 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Apr 2019 20:36:17 -0700 (PDT) From: Mathieu Poirier To: linux-arm-kernel@lists.infradead.org Cc: alexander.shishkin@linux.intel.com, peterz@infradead.org, suzuki.poulose@arm.com, mike.leach@arm.com, leo.yan@linaro.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 08/20] coresight: Properly address concurrency in sink::update() functions Date: Wed, 3 Apr 2019 21:35:29 -0600 Message-Id: <20190404033541.14072-9-mathieu.poirier@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190404033541.14072-1-mathieu.poirier@linaro.org> References: <20190404033541.14072-1-mathieu.poirier@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When operating in CPU-wide trace scenarios and working with an N:1 source/sink HW topology, update() functions need to be made atomic in order to avoid racing with start and stop operations. Signed-off-by: Mathieu Poirier Reviewed-by: Suzuki K Poulose --- drivers/hwtracing/coresight/coresight-etb10.c | 4 +++- drivers/hwtracing/coresight/coresight-tmc-etf.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index 52b7d95ab498..6b50e781dc57 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -413,7 +413,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, const u32 *barrier; u32 read_ptr, write_ptr, capacity; u32 status, read_data; - unsigned long offset, to_read; + unsigned long offset, to_read, flags; struct cs_buffers *buf = sink_config; struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); @@ -422,6 +422,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, capacity = drvdata->buffer_depth * ETB_FRAME_SIZE_WORDS; + spin_lock_irqsave(&drvdata->spinlock, flags); __etb_disable_hw(drvdata); CS_UNLOCK(drvdata->base); @@ -532,6 +533,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, } __etb_enable_hw(drvdata); CS_LOCK(drvdata->base); + spin_unlock_irqrestore(&drvdata->spinlock, flags); return to_read; } diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c index 30f868676540..a38ad2b0d95a 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -413,7 +413,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, u32 *buf_ptr; u64 read_ptr, write_ptr; u32 status; - unsigned long offset, to_read; + unsigned long offset, to_read, flags; struct cs_buffers *buf = sink_config; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); @@ -424,6 +424,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, if (WARN_ON_ONCE(drvdata->mode != CS_MODE_PERF)) return 0; + spin_lock_irqsave(&drvdata->spinlock, flags); CS_UNLOCK(drvdata->base); tmc_flush_and_stop(drvdata); @@ -517,6 +518,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, to_read = buf->nr_pages << PAGE_SHIFT; } CS_LOCK(drvdata->base); + spin_unlock_irqrestore(&drvdata->spinlock, flags); return to_read; } -- 2.17.1