3 files changed, 60 insertions, 13 deletions

diff --git a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c
index d9b420972934..26004f0c5a6a 100644
--- a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c
+++ b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c
@@ -15,6 +15,19 @@ enum bpf_obj_type {
 	BPF_OBJ_BTF,
 };
 
+struct bpf_perf_link___local {
+	struct bpf_link link;
+	struct file *perf_file;
+} __attribute__((preserve_access_index));
+
+struct perf_event___local {
+	u64 bpf_cookie;
+} __attribute__((preserve_access_index));
+
+enum bpf_link_type___local {
+	BPF_LINK_TYPE_PERF_EVENT___local = 7,
+};
+
 extern const void bpf_link_fops __ksym;
 extern const void bpf_map_fops __ksym;
 extern const void bpf_prog_fops __ksym;
@@ -38,6 +51,17 @@ static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type)
 	}
 }
 
+/* could be used only with BPF_LINK_TYPE_PERF_EVENT links */
+static __u64 get_bpf_cookie(struct bpf_link *link)
+{
+	struct bpf_perf_link___local *perf_link;
+	struct perf_event___local *event;
+
+	perf_link = container_of(link, struct bpf_perf_link___local, link);
+	event = BPF_CORE_READ(perf_link, perf_file, private_data);
+	return BPF_CORE_READ(event, bpf_cookie);
+}
+
 SEC("iter/task_file")
 int iter(struct bpf_iter__task_file *ctx)
 {
@@ -69,10 +93,24 @@ int iter(struct bpf_iter__task_file *ctx)
 	if (file->f_op != fops)
 		return 0;
 
+	__builtin_memset(&e, 0, sizeof(e));
 	e.pid = task->tgid;
 	e.id = get_obj_id(file->private_data, obj_type);
-	bpf_probe_read_kernel(&e.comm, sizeof(e.comm),
-			      task->group_leader->comm);
+
+	if (obj_type == BPF_OBJ_LINK &&
+	    bpf_core_enum_value_exists(enum bpf_link_type___local,
+				       BPF_LINK_TYPE_PERF_EVENT___local)) {
+		struct bpf_link *link = (struct bpf_link *) file->private_data;
+
+		if (link->type == bpf_core_enum_value(enum bpf_link_type___local,
+						      BPF_LINK_TYPE_PERF_EVENT___local)) {
+			e.has_bpf_cookie = true;
+			e.bpf_cookie = get_bpf_cookie(link);
+		}
+	}
+
+	bpf_probe_read_kernel_str(&e.comm, sizeof(e.comm),
+				  task->group_leader->comm);
 	bpf_seq_write(ctx->meta->seq, &e, sizeof(e));
 
 	return 0;
diff --git a/tools/bpf/bpftool/skeleton/pid_iter.h b/tools/bpf/bpftool/skeleton/pid_iter.h
index 5692cf257adb..bbb570d4cca6 100644
--- a/tools/bpf/bpftool/skeleton/pid_iter.h
+++ b/tools/bpf/bpftool/skeleton/pid_iter.h
@@ -6,6 +6,8 @@
 struct pid_iter_entry {
 	__u32 id;
 	int pid;
+	__u64 bpf_cookie;
+	bool has_bpf_cookie;
 	char comm[16];
 };
 
diff --git a/tools/bpf/bpftool/skeleton/profiler.bpf.c b/tools/bpf/bpftool/skeleton/profiler.bpf.c
index 4e3512f700c0..2f80edc682f1 100644
--- a/tools/bpf/bpftool/skeleton/profiler.bpf.c
+++ b/tools/bpf/bpftool/skeleton/profiler.bpf.c
@@ -4,6 +4,12 @@
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 
+struct bpf_perf_event_value___local {
+	__u64 counter;
+	__u64 enabled;
+	__u64 running;
+} __attribute__((preserve_access_index));
+
 /* map of perf event fds, num_cpu * num_metric entries */
 struct {
 	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
@@ -15,14 +21,14 @@ struct {
 struct {
 	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
 	__uint(key_size, sizeof(u32));
-	__uint(value_size, sizeof(struct bpf_perf_event_value));
+	__uint(value_size, sizeof(struct bpf_perf_event_value___local));
 } fentry_readings SEC(".maps");
 
 /* accumulated readings */
 struct {
 	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
 	__uint(key_size, sizeof(u32));
-	__uint(value_size, sizeof(struct bpf_perf_event_value));
+	__uint(value_size, sizeof(struct bpf_perf_event_value___local));
 } accum_readings SEC(".maps");
 
 /* sample counts, one per cpu */
@@ -39,7 +45,7 @@ const volatile __u32 num_metric = 1;
 SEC("fentry/XXX")
 int BPF_PROG(fentry_XXX)
 {
-	struct bpf_perf_event_value *ptrs[MAX_NUM_MATRICS];
+	struct bpf_perf_event_value___local *ptrs[MAX_NUM_MATRICS];
 	u32 key = bpf_get_smp_processor_id();
 	u32 i;
 
@@ -53,10 +59,10 @@ int BPF_PROG(fentry_XXX)
 	}
 
 	for (i = 0; i < num_metric && i < MAX_NUM_MATRICS; i++) {
-		struct bpf_perf_event_value reading;
+		struct bpf_perf_event_value___local reading;
 		int err;
 
-		err = bpf_perf_event_read_value(&events, key, &reading,
+		err = bpf_perf_event_read_value(&events, key, (void *)&reading,
 						sizeof(reading));
 		if (err)
 			return 0;
@@ -68,14 +74,14 @@ int BPF_PROG(fentry_XXX)
 }
 
 static inline void
-fexit_update_maps(u32 id, struct bpf_perf_event_value *after)
+fexit_update_maps(u32 id, struct bpf_perf_event_value___local *after)
 {
-	struct bpf_perf_event_value *before, diff, *accum;
+	struct bpf_perf_event_value___local *before, diff;
 
 	before = bpf_map_lookup_elem(&fentry_readings, &id);
 	/* only account samples with a valid fentry_reading */
 	if (before && before->counter) {
-		struct bpf_perf_event_value *accum;
+		struct bpf_perf_event_value___local *accum;
 
 		diff.counter = after->counter - before->counter;
 		diff.enabled = after->enabled - before->enabled;
@@ -93,16 +99,17 @@ fexit_update_maps(u32 id, struct bpf_perf_event_value *after)
 SEC("fexit/XXX")
 int BPF_PROG(fexit_XXX)
 {
-	struct bpf_perf_event_value readings[MAX_NUM_MATRICS];
+	struct bpf_perf_event_value___local readings[MAX_NUM_MATRICS];
 	u32 cpu = bpf_get_smp_processor_id();
-	u32 i, one = 1, zero = 0;
+	u32 i, zero = 0;
 	int err;
 	u64 *count;
 
 	/* read all events before updating the maps, to reduce error */
 	for (i = 0; i < num_metric && i < MAX_NUM_MATRICS; i++) {
 		err = bpf_perf_event_read_value(&events, cpu + i * num_cpu,
-						readings + i, sizeof(*readings));
+						(void *)(readings + i),
+						sizeof(*readings));
 		if (err)
 			return 0;
 	}