[PATCH perf/core 03/11] perf: Add support to attach standard unique uprobe

[Jiri Olsa <jolsa@kernel.org>]

Adding support to attach unique probe through perf uprobe pmu.

Adding new 'unique' format attribute that allows to pass the
request to create unique uprobe the uprobe consumer.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 include/linux/trace_events.h    | 2 +-
 kernel/events/core.c            | 8 ++++++--
 kernel/trace/trace_event_perf.c | 4 ++--
 kernel/trace/trace_probe.h      | 2 +-
 kernel/trace/trace_uprobe.c     | 9 +++++----
 5 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 04307a19cde3..1d35727fda27 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -877,7 +877,7 @@ extern int bpf_get_kprobe_info(const struct perf_event *event,
 #endif
 #ifdef CONFIG_UPROBE_EVENTS
 extern int  perf_uprobe_init(struct perf_event *event,
-			     unsigned long ref_ctr_offset, bool is_retprobe);
+			     unsigned long ref_ctr_offset, bool is_retprobe, bool is_unique);
 extern void perf_uprobe_destroy(struct perf_event *event);
 extern int bpf_get_uprobe_info(const struct perf_event *event,
 			       u32 *fd_type, const char **filename,
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 28de3baff792..10a9341c638f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11046,11 +11046,13 @@ EXPORT_SYMBOL_GPL(perf_tp_event);
  */
 enum perf_probe_config {
 	PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0,  /* [k,u]retprobe */
+	PERF_PROBE_CONFIG_IS_UNIQUE   = 1U << 1,  /* unique uprobe */
 	PERF_UPROBE_REF_CTR_OFFSET_BITS = 32,
 	PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS,
 };
 
 PMU_FORMAT_ATTR(retprobe, "config:0");
+PMU_FORMAT_ATTR(unique, "config:1");
 #endif
 
 #ifdef CONFIG_KPROBE_EVENTS
@@ -11114,6 +11116,7 @@ PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63");
 
 static struct attribute *uprobe_attrs[] = {
 	&format_attr_retprobe.attr,
+	&format_attr_unique.attr,
 	&format_attr_ref_ctr_offset.attr,
 	NULL,
 };
@@ -11144,7 +11147,7 @@ static int perf_uprobe_event_init(struct perf_event *event)
 {
 	int err;
 	unsigned long ref_ctr_offset;
-	bool is_retprobe;
+	bool is_retprobe, is_unique;
 
 	if (event->attr.type != perf_uprobe.type)
 		return -ENOENT;
@@ -11159,8 +11162,9 @@ static int perf_uprobe_event_init(struct perf_event *event)
 		return -EOPNOTSUPP;
 
 	is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE;
+	is_unique = event->attr.config & PERF_PROBE_CONFIG_IS_UNIQUE;
 	ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT;
-	err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe);
+	err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe, is_unique);
 	if (err)
 		return err;
 
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index a6bb7577e8c5..b4383ab21d88 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -296,7 +296,7 @@ void perf_kprobe_destroy(struct perf_event *p_event)
 
 #ifdef CONFIG_UPROBE_EVENTS
 int perf_uprobe_init(struct perf_event *p_event,
-		     unsigned long ref_ctr_offset, bool is_retprobe)
+		     unsigned long ref_ctr_offset, bool is_retprobe, bool is_unique)
 {
 	int ret;
 	char *path = NULL;
@@ -317,7 +317,7 @@ int perf_uprobe_init(struct perf_event *p_event,
 	}
 
 	tp_event = create_local_trace_uprobe(path, p_event->attr.probe_offset,
-					     ref_ctr_offset, is_retprobe);
+					     ref_ctr_offset, is_retprobe, is_unique);
 	if (IS_ERR(tp_event)) {
 		ret = PTR_ERR(tp_event);
 		goto out;
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 842383fbc03b..92870b98b296 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -469,7 +469,7 @@ extern void destroy_local_trace_kprobe(struct trace_event_call *event_call);
 
 extern struct trace_event_call *
 create_local_trace_uprobe(char *name, unsigned long offs,
-			  unsigned long ref_ctr_offset, bool is_return);
+			  unsigned long ref_ctr_offset, bool is_return, bool is_unique);
 extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
 #endif
 extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 8b0bcc0d8f41..4ecb6083f949 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -333,7 +333,7 @@ trace_uprobe_primary_from_call(struct trace_event_call *call)
  * Allocate new trace_uprobe and initialize it (including uprobes).
  */
 static struct trace_uprobe *
-alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
+alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret, bool is_unique)
 {
 	struct trace_uprobe *tu;
 	int ret;
@@ -356,6 +356,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
 	tu->consumer.handler = uprobe_dispatcher;
 	if (is_ret)
 		tu->consumer.ret_handler = uretprobe_dispatcher;
+	tu->consumer.is_unique = is_unique;
 	init_trace_uprobe_filter(tu->tp.event->filter);
 	return tu;
 
@@ -688,7 +689,7 @@ static int __trace_uprobe_create(int argc, const char **argv)
 	argc -= 2;
 	argv += 2;
 
-	tu = alloc_trace_uprobe(group, event, argc, is_return);
+	tu = alloc_trace_uprobe(group, event, argc, is_return, false /* unique */);
 	if (IS_ERR(tu)) {
 		ret = PTR_ERR(tu);
 		/* This must return -ENOMEM otherwise there is a bug */
@@ -1636,7 +1637,7 @@ static int unregister_uprobe_event(struct trace_uprobe *tu)
 #ifdef CONFIG_PERF_EVENTS
 struct trace_event_call *
 create_local_trace_uprobe(char *name, unsigned long offs,
-			  unsigned long ref_ctr_offset, bool is_return)
+			  unsigned long ref_ctr_offset, bool is_return, bool is_unique)
 {
 	enum probe_print_type ptype;
 	struct trace_uprobe *tu;
@@ -1658,7 +1659,7 @@ create_local_trace_uprobe(char *name, unsigned long offs,
 	 * duplicated name "DUMMY_EVENT" here.
 	 */
 	tu = alloc_trace_uprobe(UPROBE_EVENT_SYSTEM, "DUMMY_EVENT", 0,
-				is_return);
+				is_return, is_unique);
 
 	if (IS_ERR(tu)) {
 		pr_info("Failed to allocate trace_uprobe.(%d)\n",
-- 
2.51.0