int ret;
};
-static int find_cpu_to_read(struct perf_event *event, int local_cpu)
+static int __perf_event_read_cpu(struct perf_event *event, int event_cpu)
{
- int event_cpu = event->oncpu;
u16 local_pkg, event_pkg;
if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) {
- event_pkg = topology_physical_package_id(event_cpu);
- local_pkg = topology_physical_package_id(local_cpu);
+ int local_cpu = smp_processor_id();
+
+ event_pkg = topology_physical_package_id(event_cpu);
+ local_pkg = topology_physical_package_id(local_cpu);
if (event_pkg == local_pkg)
return local_cpu;
static int perf_event_read(struct perf_event *event, bool group)
{
- int ret = 0, cpu_to_read, local_cpu;
+ int event_cpu, ret = 0;
/*
* If event is enabled and currently active on a CPU, update the
.ret = 0,
};
- local_cpu = get_cpu();
- cpu_to_read = find_cpu_to_read(event, local_cpu);
- put_cpu();
+ event_cpu = READ_ONCE(event->oncpu);
+ if ((unsigned)event_cpu >= nr_cpu_ids)
+ return 0;
+
+ preempt_disable();
+ event_cpu = __perf_event_read_cpu(event, event_cpu);
/*
* Purposely ignore the smp_call_function_single() return
* value.
*
- * If event->oncpu isn't a valid CPU it means the event got
+ * If event_cpu isn't a valid CPU it means the event got
* scheduled out and that will have updated the event count.
*
* Therefore, either way, we'll have an up-to-date event count
* after this.
*/
- (void)smp_call_function_single(cpu_to_read, __perf_event_read, &data, 1);
+ (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1);
+ preempt_enable();
ret = data.ret;
} else if (event->state == PERF_EVENT_STATE_INACTIVE) {
struct perf_event_context *ctx = event->ctx;
if (task == TASK_TOMBSTONE)
return;
+ if (!ifh->nr_file_filters)
+ return;
+
mm = get_task_mm(event->ctx->task);
if (!mm)
goto restart;
if (!filename)
goto fail;
+ /*
+ * For now, we only support file-based filters
+ * in per-task events; doing so for CPU-wide
+ * events requires additional context switching
+ * trickery, since same object code will be
+ * mapped at different virtual addresses in
+ * different processes.
+ */
+ ret = -EOPNOTSUPP;
+ if (!event->ctx->task)
+ goto fail_free_name;
+
/* look up the path and grab its inode */
ret = kern_path(filename, LOOKUP_FOLLOW, &path);
if (ret)
!S_ISREG(filter->inode->i_mode))
/* free_filters_list() will iput() */
goto fail;
+
+ event->addr_filters.nr_file_filters++;
}
/* ready to consume more filters */
if (WARN_ON_ONCE(event->parent))
return -EINVAL;
- /*
- * For now, we only support filtering in per-task events; doing so
- * for CPU-wide events requires additional context switching trickery,
- * since same object code will be mapped at different virtual
- * addresses in different processes.
- */
- if (!event->ctx->task)
- return -EOPNOTSUPP;
-
ret = perf_event_parse_addr_filter(event, filter_str, &filters);
if (ret)
- return ret;
+ goto fail_clear_files;
ret = event->pmu->addr_filters_validate(&filters);
- if (ret) {
- free_filters_list(&filters);
- return ret;
- }
+ if (ret)
+ goto fail_free_filters;
/* remove existing filters, if any */
perf_addr_filters_splice(event, &filters);
/* install new filters */
perf_event_for_each_child(event, perf_event_addr_filters_apply);
+ return ret;
+
+fail_free_filters:
+ free_filters_list(&filters);
+
+fail_clear_files:
+ event->addr_filters.nr_file_filters = 0;
+
return ret;
}