diff options
author | Mathieu Poirier <mathieu.poirier@linaro.org> | 2019-01-31 11:47:10 -0700 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2019-02-06 10:00:39 -0300 |
commit | 2264439258870ed258e190491c54cfb8fc7fa955 (patch) | |
tree | 888cbab622810129326ca19f6a8a5ce711cf166a /drivers/hwtracing/coresight/coresight.c | |
parent | bb8e370bdc141ddff526e5e5ee74210c91fee0b8 (diff) |
coresight: Use event attributes for sink selection
This patch uses the information conveyed by perf_event::attr::config2
to select a sink to use for the session. That way a sink can easily be
selected to be used by more than one source, something that isn't currently
possible with the sysfs implementation.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-4-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'drivers/hwtracing/coresight/coresight.c')
-rw-r--r-- | drivers/hwtracing/coresight/coresight.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index d7fa90be6f42..29cef898afba 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -11,6 +11,7 @@ #include <linux/err.h> #include <linux/export.h> #include <linux/slab.h> +#include <linux/stringhash.h> #include <linux/mutex.h> #include <linux/clk.h> #include <linux/coresight.h> @@ -541,6 +542,47 @@ struct coresight_device *coresight_get_enabled_sink(bool deactivate) return dev ? to_coresight_device(dev) : NULL; } +static int coresight_sink_by_id(struct device *dev, void *data) +{ + struct coresight_device *csdev = to_coresight_device(dev); + unsigned long hash; + + if (csdev->type == CORESIGHT_DEV_TYPE_SINK || + csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) { + + if (!csdev->ea) + return 0; + /* + * See function etm_perf_add_symlink_sink() to know where + * this comes from. + */ + hash = (unsigned long)csdev->ea->var; + + if ((u32)hash == *(u32 *)data) + return 1; + } + + return 0; +} + +/** + * coresight_get_sink_by_id - returns the sink that matches the id + * @id: Id of the sink to match + * + * The name of a sink is unique, whether it is found on the AMBA bus or + * otherwise. As such the hash of that name can easily be used to identify + * a sink. + */ +struct coresight_device *coresight_get_sink_by_id(u32 id) +{ + struct device *dev = NULL; + + dev = bus_find_device(&coresight_bustype, NULL, &id, + coresight_sink_by_id); + + return dev ? to_coresight_device(dev) : NULL; +} + /* * coresight_grab_device - Power up this device and any of the helper * devices connected to it for trace operation. Since the helper devices |