logging: log_cmds: Add support for frontend runtime filtering

Add support for controlling runtime filtering for frontend.

Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>

subsys/logging/log_cmds.c

@@ -11,6 +11,9 @@
 #include <zephyr/sys/iterable_sections.h>
 #include <string.h>
 
+#define FRONTEND_NAME frontend
+#define FRONTEND_STR STRINGIFY(frontend)
+
 typedef int (*log_backend_cmd_t)(const struct shell *sh,
 				 const struct log_backend *backend,
 				 size_t argc,
@@ -76,6 +79,14 @@ static int shell_backend_cmd_execute(const struct shell *sh,
 	 * be found at -1 (log backend <name> command).
 	 */
 	char const *name = argv[-1];
+	size_t slen = sizeof(FRONTEND_STR);
+
+	if (IS_ENABLED(CONFIG_LOG_FRONTEND) &&
+	    strncmp(name, FRONTEND_STR, slen) == 0) {
+		func(sh, NULL, argc, argv);
+		return 0;
+	}
+
 	const struct log_backend *backend = backend_find(name);
 
 	if (backend != NULL) {
@@ -84,6 +95,7 @@ static int shell_backend_cmd_execute(const struct shell *sh,
 		shell_error(sh, "Invalid backend: %s", name);
 		return -ENOEXEC;
 	}
+
 	return 0;
 }
 
@@ -96,7 +108,7 @@ static int log_status(const struct shell *sh,
 	uint32_t dynamic_lvl;
 	uint32_t compiled_lvl;
 
-	if (!log_backend_is_active(backend)) {
+	if (backend && !log_backend_is_active(backend)) {
 		shell_warn(sh, "Logs are halted!");
 	}
 
@@ -106,10 +118,13 @@ static int log_status(const struct shell *sh,
 	      "----------------------------------------------------------\r\n");
 
 	for (int16_t i = 0U; i < modules_cnt; i++) {
-		dynamic_lvl = log_filter_get(backend, Z_LOG_LOCAL_DOMAIN_ID,
-					     i, true);
-		compiled_lvl = log_filter_get(backend, Z_LOG_LOCAL_DOMAIN_ID,
-					      i, false);
+		if (IS_ENABLED(CONFIG_LOG_FRONTEND) && !backend) {
+			dynamic_lvl = log_frontend_filter_get(i, true);
+			compiled_lvl = log_frontend_filter_get(i, false);
+		} else {
+			dynamic_lvl = log_filter_get(backend, Z_LOG_LOCAL_DOMAIN_ID, i, true);
+			compiled_lvl = log_filter_get(backend, Z_LOG_LOCAL_DOMAIN_ID, i, false);
+		}
 
 		shell_fprintf(sh, SHELL_NORMAL, "%-40s | %-7s | %s\r\n",
 			      log_source_name_get(Z_LOG_LOCAL_DOMAIN_ID, i),
@@ -163,16 +178,20 @@ static void filters_set(const struct shell *sh,
 	bool all = argc ? false : true;
 	int cnt = all ? log_src_cnt_get(Z_LOG_LOCAL_DOMAIN_ID) : argc;
 
-	if (!backend->cb->active) {
+	if (backend && !backend->cb->active) {
 		shell_warn(sh, "Backend not active.");
 	}
 
 	for (i = 0; i < cnt; i++) {
 		id = all ? i : module_id_get(argv[i]);
 		if (id >= 0) {
-			uint32_t set_lvl = log_filter_set(backend,
-						       Z_LOG_LOCAL_DOMAIN_ID,
-						       id, level);
+			uint32_t set_lvl;
+
+			if (IS_ENABLED(CONFIG_LOG_FRONTEND) && !backend) {
+				set_lvl = log_frontend_filter_set(id, level);
+			} else {
+				set_lvl = log_filter_set(backend, Z_LOG_LOCAL_DOMAIN_ID, id, level);
+			}
 
 			if (set_lvl != level) {
 				const char *name;
@@ -290,7 +309,13 @@ static int log_halt(const struct shell *sh,
 		    size_t argc,
 		    char **argv)
 {
-	log_backend_deactivate(backend);
+	if (backend || !IS_ENABLED(CONFIG_LOG_FRONTEND)) {
+		log_backend_deactivate(backend);
+		return 0;
+	}
+
+	shell_warn(sh, "Not supported for frontend");
+
 	return 0;
 }
 
@@ -316,7 +341,13 @@ static int log_go(const struct shell *sh,
 		  size_t argc,
 		  char **argv)
 {
-	log_backend_activate(backend, backend->cb->ctx);
+	if (backend || !IS_ENABLED(CONFIG_LOG_FRONTEND)) {
+		log_backend_activate(backend, backend->cb->ctx);
+		return 0;
+	}
+
+	shell_warn(sh, "Not supported for frontend");
+
 	return 0;
 }
 
@@ -351,6 +382,11 @@ static int cmd_log_backends_list(const struct shell *sh,
 			      backend->cb->id);
 
 	}
+
+	if (IS_ENABLED(CONFIG_LOG_FRONTEND)) {
+		shell_print(sh, "%s", FRONTEND_STR);
+	}
+
 	return 0;
 }
 
@@ -409,12 +445,15 @@ static void backend_name_get(size_t idx, struct shell_static_entry *entry)
 
 	STRUCT_SECTION_COUNT(log_backend, &section_count);
 
+
 	if (idx < section_count) {
 		struct log_backend *backend = NULL;
 
 		STRUCT_SECTION_GET(log_backend, idx, &backend);
 		__ASSERT_NO_MSG(backend != NULL);
 		entry->syntax = backend->name;
+	} else if (IS_ENABLED(CONFIG_LOG_FRONTEND) && (idx == section_count)) {
+		entry->syntax = FRONTEND_STR;
 	}
 }
 
@@ -438,6 +477,8 @@ SHELL_STATIC_SUBCMD_SET_CREATE(
 		       cmd_log_self_status),
 	SHELL_COND_CMD(CONFIG_LOG_MODE_DEFERRED, mem, NULL, "Logger memory usage",
 		       cmd_log_mem),
+	SHELL_COND_CMD(CONFIG_LOG_FRONTEND, FRONTEND_NAME, &sub_log_backend,
+		"Frontend control", NULL),
 	SHELL_SUBCMD_SET_END);
 
 SHELL_CMD_REGISTER(log, &sub_log_stat, "Commands for controlling logger",