From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932854AbcHKQVh (ORCPT ); Thu, 11 Aug 2016 12:21:37 -0400 Received: from mail-io0-f177.google.com ([209.85.223.177]:32828 "EHLO mail-io0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932813AbcHKQVc (ORCPT ); Thu, 11 Aug 2016 12:21:32 -0400 From: Mathieu Poirier To: peterz@infradead.org Cc: acme@kernel.org, jolsa@kernel.org, mingo@redhat.com, vince@deater.net, mtk.manpages@gmail.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Mathieu Poirier Subject: [PATCH V5 8/9] coresight: adding sink parameter to function coresight_build_path() Date: Thu, 11 Aug 2016 10:21:03 -0600 Message-Id: <1470932464-726-9-git-send-email-mathieu.poirier@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1470932464-726-1-git-send-email-mathieu.poirier@linaro.org> References: <1470932464-726-1-git-send-email-mathieu.poirier@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Up to now function coresight_build_path() was counting on a sink to have been selected (from sysFS) prior to being called. This patch adds a string argument so that a sink matching the argument can be selected. Signed-off-by: Mathieu Poirier --- drivers/hwtracing/coresight/coresight-etm-perf.c | 2 +- drivers/hwtracing/coresight/coresight-priv.h | 3 +- drivers/hwtracing/coresight/coresight.c | 43 ++++++++++++++++-------- 3 files changed, 32 insertions(+), 16 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index f4174f36c5a0..f8c7a8733b23 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -184,7 +184,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, * list of devices from source to sink that can be * referenced later when the path is actually needed. */ - event_data->path[cpu] = coresight_build_path(csdev); + event_data->path[cpu] = coresight_build_path(csdev, NULL); if (!event_data->path[cpu]) goto err; } diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index 39841d1f58e0..8a35dbf4cd1b 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -103,7 +103,8 @@ static inline void CS_UNLOCK(void __iomem *addr) void coresight_disable_path(struct list_head *path); int coresight_enable_path(struct list_head *path, u32 mode); struct coresight_device *coresight_get_sink(struct list_head *path); -struct list_head *coresight_build_path(struct coresight_device *csdev); +struct list_head *coresight_build_path(struct coresight_device *csdev, + const char *sink); void coresight_release_path(struct list_head *path); #ifdef CONFIG_CORESIGHT_SOURCE_ETM3X diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index bb20ee9747e1..d52e1ed94210 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -372,30 +372,44 @@ struct coresight_device *coresight_get_sink(struct list_head *path) * _coresight_build_path - recursively build a path from a @csdev to a sink. * @csdev: The device to start from. * @path: The list to add devices to. + * @sink: The name of the sink this path should connect with. * - * The tree of Coresight device is traversed until an activated sink is - * found. From there the sink is added to the list along with all the - * devices that led to that point - the end result is a list from source - * to sink. In that list the source is the first device and the sink the - * last one. + * The tree of Coresight device is traversed until an activated sink or + * the one specified by @sink is found. + * From there the sink is added to the list along with all the devices that + * led to that point - the end result is a list from source to sink. In that + * list the source is the first device and the sink the last one. */ static int _coresight_build_path(struct coresight_device *csdev, - struct list_head *path) + struct list_head *path, const char *sink) { int i; bool found = false; struct coresight_node *node; - /* An activated sink has been found. Enqueue the element */ - if ((csdev->type == CORESIGHT_DEV_TYPE_SINK || - csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) && csdev->activated) - goto out; + /* + * First see if we are dealing with a sink. If we have one check if + * it was selected via sysFS or the perf cmd line. + */ + if (csdev->type == CORESIGHT_DEV_TYPE_SINK || + csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) { + /* Discourage meddling in sysFS if using the perf interface */ + if (sink && csdev->activated) + return -EINVAL; + /* Activated via perf cmd line */ + if (sink && !strcmp(dev_name(&csdev->dev), sink)) + goto out; + /* Activated via sysFS */ + if (csdev->activated) + goto out; + } /* Not a sink - recursively explore each port found on this element */ for (i = 0; i < csdev->nr_outport; i++) { struct coresight_device *child_dev = csdev->conns[i].child_dev; - if (child_dev && _coresight_build_path(child_dev, path) == 0) { + if (child_dev && + _coresight_build_path(child_dev, path, sink) == 0) { found = true; break; } @@ -422,7 +436,8 @@ out: return 0; } -struct list_head *coresight_build_path(struct coresight_device *csdev) +struct list_head *coresight_build_path(struct coresight_device *csdev, + const char *sink) { struct list_head *path; int rc; @@ -433,7 +448,7 @@ struct list_head *coresight_build_path(struct coresight_device *csdev) INIT_LIST_HEAD(path); - rc = _coresight_build_path(csdev, path); + rc = _coresight_build_path(csdev, path, sink); if (rc) { kfree(path); return ERR_PTR(rc); @@ -508,7 +523,7 @@ int coresight_enable(struct coresight_device *csdev) if (csdev->enable) goto out; - path = coresight_build_path(csdev); + path = coresight_build_path(csdev, NULL); if (IS_ERR(path)) { pr_err("building path(s) failed\n"); ret = PTR_ERR(path); -- 2.7.4