From: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Date: Mon, 6 Jun 2022 22:00:30 +0000 (-0400)
Subject: Custom upgrade: refactor: ust_app_find_by_pid -> ust_app_with_pid_exists
X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=commitdiff_plain;h=refs%2Fheads%2F2.13-custom-upgrade

Custom upgrade: refactor: ust_app_find_by_pid -> ust_app_with_pid_exists

ust_app_find_by_pid is only used to check if apps should be updated. No
need to return a ust_app. When a ust_app will be necessary, multiple
ust_app objects could be returned.

Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Change-Id: Ic6d2ff9820591ca85021ce701982136424792a22
---

diff --git a/src/bin/lttng-sessiond/trace-ust.c b/src/bin/lttng-sessiond/trace-ust.c
index b6e756cc6..b28e5317e 100644
--- a/src/bin/lttng-sessiond/trace-ust.c
+++ b/src/bin/lttng-sessiond/trace-ust.c
@@ -987,7 +987,6 @@ enum lttng_error_code trace_ust_process_attr_tracker_inclusion_set_add_value(
 	struct process_attr_tracker *tracker;
 	int integral_value;
 	enum process_attr_tracker_status status;
-	struct ust_app *app;
 
 	/*
 	 * Convert process attribute tracker value to the integral
@@ -1067,10 +1066,7 @@ enum lttng_error_code trace_ust_process_attr_tracker_inclusion_set_add_value(
 	/* Add session to application */
 	switch (process_attr) {
 	case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
-		app = ust_app_find_by_pid(integral_value);
-		if (app) {
-			should_update_apps = true;
-		}
+		should_update_apps = ust_app_with_pid_exists(integral_value);
 		break;
 	default:
 		should_update_apps = true;
@@ -1096,7 +1092,6 @@ enum lttng_error_code trace_ust_process_attr_tracker_inclusion_set_remove_value(
 	struct process_attr_tracker *tracker;
 	int integral_value;
 	enum process_attr_tracker_status status;
-	struct ust_app *app;
 
 	/*
 	 * Convert process attribute tracker value to the integral
@@ -1177,10 +1172,7 @@ enum lttng_error_code trace_ust_process_attr_tracker_inclusion_set_remove_value(
 	/* Add session to application */
 	switch (process_attr) {
 	case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
-		app = ust_app_find_by_pid(integral_value);
-		if (app) {
-			should_update_apps = true;
-		}
+		should_update_apps = ust_app_with_pid_exists(integral_value);
 		break;
 	default:
 		should_update_apps = true;
diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index 409fb3590..e180bff2a 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -3910,28 +3910,25 @@ error:
 }
 
 /*
- * Return ust app pointer or NULL if not found. RCU read side lock MUST be
+ * Check if a ust_app with a given pid is present. RCU read side lock MUST be
  * acquired before calling this function.
  */
-struct ust_app *ust_app_find_by_pid(pid_t pid)
+bool ust_app_with_pid_exists(pid_t pid)
 {
-	struct ust_app *app = NULL;
 	struct lttng_ht_node_ulong *node;
 	struct lttng_ht_iter iter;
+	bool present = false;
 
 	lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
 	node = lttng_ht_iter_get_node_ulong(&iter);
 	if (node == NULL) {
-		DBG2("UST app no found with pid %d", pid);
-		goto error;
+		DBG2("UST app not found with pid %d", pid);
+		goto end;
 	}
 
-	DBG2("Found UST app by pid %d", pid);
-
-	app = caa_container_of(node, struct ust_app, pid_n);
-
-error:
-	return app;
+	present = true;
+end:
+	return present;
 }
 
 /*
diff --git a/src/bin/lttng-sessiond/ust-app.h b/src/bin/lttng-sessiond/ust-app.h
index 4a7a7c92d..7bdc80988 100644
--- a/src/bin/lttng-sessiond/ust-app.h
+++ b/src/bin/lttng-sessiond/ust-app.h
@@ -362,7 +362,7 @@ void ust_app_global_update_all_event_notifier_rules(void);
 
 void ust_app_clean_list(void);
 int ust_app_ht_alloc(void);
-struct ust_app *ust_app_find_by_pid(pid_t pid);
+bool ust_app_with_pid_exists(pid_t pid);
 struct ust_app_stream *ust_app_alloc_stream(void);
 int ust_app_recv_registration(int sock, struct ust_register_msg *msg);
 int ust_app_recv_notify(int sock);
@@ -614,9 +614,9 @@ struct ust_app *ust_app_find_by_sock(int sock)
 	return NULL;
 }
 static inline
-struct ust_app *ust_app_find_by_pid(pid_t pid)
+bool ust_app_with_pid_exists(pid_t pid)
 {
-	return NULL;
+	return false;
 }
 static inline
 uint64_t ust_app_get_size_one_more_packet_per_stream(