From f73f20e1fcc9fcdc7557fd1c4b1b72f924478688 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Mon, 5 Jun 2017 14:15:02 -0600 Subject: [PATCH] coresight: Disable the path only when the source is disabled With a coresight tracing session, the components along the path from the source to sink are disabled after the source is disabled. However, if the source was not actually disabled due to active users, we should not disable the components in the path. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 0c37356e417c..532a2acfa8cc 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -253,14 +253,22 @@ static int coresight_enable_source(struct coresight_device *csdev, u32 mode) return 0; } -static void coresight_disable_source(struct coresight_device *csdev) +/** + * coresight_disable_source - Drop the reference count by 1 and disable + * the device if there are no users left. + * + * @csdev - The coresight device to disable + * + * Returns true if the device has been disabled. + */ +static bool coresight_disable_source(struct coresight_device *csdev) { if (atomic_dec_return(csdev->refcnt) == 0) { - if (source_ops(csdev)->disable) { + if (source_ops(csdev)->disable) source_ops(csdev)->disable(csdev, NULL); - csdev->enable = false; - } + csdev->enable = false; } + return !csdev->enable; } void coresight_disable_path(struct list_head *path) @@ -629,7 +637,7 @@ void coresight_disable(struct coresight_device *csdev) if (ret) goto out; - if (!csdev->enable) + if (!csdev->enable || !coresight_disable_source(csdev)) goto out; switch (csdev->subtype.source_subtype) { @@ -647,7 +655,6 @@ void coresight_disable(struct coresight_device *csdev) break; } - coresight_disable_source(csdev); coresight_disable_path(path); coresight_release_path(path); -- 2.20.1