Re: [PATCH v6 2/4] bpf: Add new bpf map type to store the pointer to struct perf_event

On Tue, Aug 04, 2015 at 10:43:35AM -0700, Alexei Starovoitov wrote:

quoted

+static void *perf_event_fd_array_get_ptr(struct bpf_map *map, int fd)
+{
+	struct perf_event *event;
+	struct perf_event_attr *attr;
+
+	event = perf_event_get(fd);
+	if (IS_ERR(event))
+		return event;
+
+	attr = perf_event_attrs(event);
+	if (IS_ERR(attr))
+		return attr;
+
+	if (attr->type != PERF_TYPE_RAW &&
+	    attr->type != PERF_TYPE_HARDWARE) {
+		perf_event_release_kernel(event);
+		return ERR_PTR(-EINVAL);
+	}
+	return event;
+}

I'm not sure whether Peter wanted to see the above function to be
in events/core.c or not.
imo it's fine here, since perf_event_attr is an uapi struct.

Right, aside from the const issue this is fine, for the exact reason you
state, perf_event_attr is an exposed interface.