On 18/07/16 20:51, Mathieu Poirier wrote:
This patch implements the required API needed to access
and retrieve range and start/stop filters from the perf core.
Signed-off-by: Mathieu Poirier <mathieu.poir...@linaro.org>
---
drivers/hwtracing/coresight/coresight-etm-perf.c | 146 ++++++++++++++++++++---
drivers/hwtracing/coresight/coresight-etm-perf.h | 32 +++++
2 files changed, 162 insertions(+), 16 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c
b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 78a1bc0013a2..fde7f42149c5 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -29,6 +29,7 @@
#include <linux/workqueue.h>
#include "coresight-priv.h"
+#include "coresight-etm-perf.h"
static struct pmu etm_pmu;
static bool etm_perf_up;
@@ -83,12 +84,44 @@ static const struct attribute_group *etm_pmu_attr_groups[]
= {
static void etm_event_read(struct perf_event *event) {}
+static int etm_addr_filters_alloc(struct perf_event *event)
+{
...
+ return 0;
+}
+
+
static int etm_event_init(struct perf_event *event)
{
+ int ret;
+
if (event->attr.type != etm_pmu.type)
return -ENOENT;
- return 0;
+ ret = etm_addr_filters_alloc(event);
}
static void free_event_data(struct work_struct *work)
@@ -456,6 +489,85 @@ static void etm_free_drv_configs(struct perf_event *event)
}
}
+static int etm_addr_filters_validate(struct list_head *filters)
+{
+
+ return 0;
+}
+
+static void etm_addr_filters_sync(struct perf_event *event)
+{
+ struct perf_addr_filters_head *head = perf_event_addr_filters(event);
+ unsigned long start, stop, *offs = event->addr_filters_offs;
+ struct etm_filters *filters = event->hw.addr_filters;
+ struct perf_addr_filter *filter;
+ int i = 0;
Is it possible to delay the etm_addr_filters_alloc() until this point ?
I understand that this function cannot report back failures if we fail
to allocate memory. Or may be do a lazy allocation from addr_filters_validate(),
when we get the first filter added.
Of course this could be done as a follow up patch to improve things once
we get the initial framework in.
+
+ list_for_each_entry(filter, &head->list, entry) {
+ start = filter->offset + offs[i];
+ stop = start + filter->size;
+
+ if (filter->range == 1) {
+ filters->filter[i].start_addr = start;
+ filters->filter[i].stop_addr = stop;
+ filters->filter[i].type = ETM_ADDR_TYPE_RANGE;
+ } else {
+ if (filter->filter == 1) {
+ filters->filter[i].start_addr = start;
+ filters->filter[i].type = ETM_ADDR_TYPE_START;
+ } else {
+ filters->filter[i].stop_addr = stop;
+ filters->filter[i].type = ETM_ADDR_TYPE_STOP;
+ }
+ }
+ i++;
+ }
+
+ filters->nr_filters = i;
+/**
+ * struct etm_filters - set of filters for a session
+ * @etm_filter: All the filters for this session.
+ * @nr_filters: Number of filters
+ * @ssstatus: Status of the start/stop logic.
+ */
+struct etm_filters {
+ struct etm_filter filter[ETM_ADDR_CMP_MAX];
nit: having the variable renamed to etm_filter will make the code a bit more
readable
where we populate/validate the filters.
Otherwise looks good
Suzuki
