X-Git-Url: http://git.monstr.eu/?a=blobdiff_plain;f=kernel%2Ftrace%2Ftrace_boot.c;h=8d252f63cd784b66fe8453b4334368bbc12e9048;hb=ce4c8f882041341cbb3f1b4632b20440692cbccc;hp=94ef2d099e3223dfd018c1c61a59c6fab4cd258e;hpb=8b7084b848cd9d7071ed9e253e1c600a25f72ddd;p=linux-2.6-microblaze.git

diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 94ef2d099e32..8d252f63cd78 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -171,6 +171,289 @@ trace_boot_add_synth_event(struct xbc_node *node, const char *event)
 }
 #endif
 
+#ifdef CONFIG_HIST_TRIGGERS
+static int __init __printf(3, 4)
+append_printf(char **bufp, char *end, const char *fmt, ...)
+{
+	va_list args;
+	int ret;
+
+	if (*bufp == end)
+		return -ENOSPC;
+
+	va_start(args, fmt);
+	ret = vsnprintf(*bufp, end - *bufp, fmt, args);
+	if (ret < end - *bufp) {
+		*bufp += ret;
+	} else {
+		*bufp = end;
+		ret = -ERANGE;
+	}
+	va_end(args);
+
+	return ret;
+}
+
+static int __init
+append_str_nospace(char **bufp, char *end, const char *str)
+{
+	char *p = *bufp;
+	int len;
+
+	while (p < end - 1 && *str != '\0') {
+		if (!isspace(*str))
+			*(p++) = *str;
+		str++;
+	}
+	*p = '\0';
+	if (p == end - 1) {
+		*bufp = end;
+		return -ENOSPC;
+	}
+	len = p - *bufp;
+	*bufp = p;
+	return (int)len;
+}
+
+static int __init
+trace_boot_hist_add_array(struct xbc_node *hnode, char **bufp,
+			  char *end, const char *key)
+{
+	struct xbc_node *anode;
+	const char *p;
+	char sep;
+
+	p = xbc_node_find_value(hnode, key, &anode);
+	if (p) {
+		if (!anode) {
+			pr_err("hist.%s requires value(s).\n", key);
+			return -EINVAL;
+		}
+
+		append_printf(bufp, end, ":%s", key);
+		sep = '=';
+		xbc_array_for_each_value(anode, p) {
+			append_printf(bufp, end, "%c%s", sep, p);
+			if (sep == '=')
+				sep = ',';
+		}
+	} else
+		return -ENOENT;
+
+	return 0;
+}
+
+static int __init
+trace_boot_hist_add_one_handler(struct xbc_node *hnode, char **bufp,
+				char *end, const char *handler,
+				const char *param)
+{
+	struct xbc_node *knode, *anode;
+	const char *p;
+	char sep;
+
+	/* Compose 'handler' parameter */
+	p = xbc_node_find_value(hnode, param, NULL);
+	if (!p) {
+		pr_err("hist.%s requires '%s' option.\n",
+		       xbc_node_get_data(hnode), param);
+		return -EINVAL;
+	}
+	append_printf(bufp, end, ":%s(%s)", handler, p);
+
+	/* Compose 'action' parameter */
+	knode = xbc_node_find_subkey(hnode, "trace");
+	if (!knode)
+		knode = xbc_node_find_subkey(hnode, "save");
+
+	if (knode) {
+		anode = xbc_node_get_child(knode);
+		if (!anode || !xbc_node_is_value(anode)) {
+			pr_err("hist.%s.%s requires value(s).\n",
+			       xbc_node_get_data(hnode),
+			       xbc_node_get_data(knode));
+			return -EINVAL;
+		}
+
+		append_printf(bufp, end, ".%s", xbc_node_get_data(knode));
+		sep = '(';
+		xbc_array_for_each_value(anode, p) {
+			append_printf(bufp, end, "%c%s", sep, p);
+			if (sep == '(')
+				sep = ',';
+		}
+		append_printf(bufp, end, ")");
+	} else if (xbc_node_find_subkey(hnode, "snapshot")) {
+		append_printf(bufp, end, ".snapshot()");
+	} else {
+		pr_err("hist.%s requires an action.\n",
+		       xbc_node_get_data(hnode));
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __init
+trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
+			     char *end, const char *param)
+{
+	struct xbc_node *node;
+	const char *p, *handler;
+	int ret;
+
+	handler = xbc_node_get_data(hnode);
+
+	xbc_node_for_each_subkey(hnode, node) {
+		p = xbc_node_get_data(node);
+		if (!isdigit(p[0]))
+			continue;
+		/* All digit started node should be instances. */
+		ret = trace_boot_hist_add_one_handler(node, bufp, end, handler, param);
+		if (ret < 0)
+			break;
+	}
+
+	if (xbc_node_find_subkey(hnode, param))
+		ret = trace_boot_hist_add_one_handler(hnode, bufp, end, handler, param);
+
+	return ret;
+}
+
+/*
+ * Histogram boottime tracing syntax.
+ *
+ * ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist[.N] {
+ *	keys = <KEY>[,...]
+ *	values = <VAL>[,...]
+ *	sort = <SORT-KEY>[,...]
+ *	size = <ENTRIES>
+ *	name = <HISTNAME>
+ *	var { <VAR> = <EXPR> ... }
+ *	pause|continue|clear
+ *	onmax|onchange[.N] { var = <VAR>; <ACTION> [= <PARAM>] }
+ *	onmatch[.N] { event = <EVENT>; <ACTION> [= <PARAM>] }
+ *	filter = <FILTER>
+ * }
+ *
+ * Where <ACTION> are;
+ *
+ *	trace = <EVENT>, <ARG1>[, ...]
+ *	save = <ARG1>[, ...]
+ *	snapshot
+ */
+static int __init
+trace_boot_compose_hist_cmd(struct xbc_node *hnode, char *buf, size_t size)
+{
+	struct xbc_node *node, *knode;
+	char *end = buf + size;
+	const char *p;
+	int ret = 0;
+
+	append_printf(&buf, end, "hist");
+
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "keys");
+	if (ret < 0) {
+		if (ret == -ENOENT)
+			pr_err("hist requires keys.\n");
+		return -EINVAL;
+	}
+
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "values");
+	if (ret == -EINVAL)
+		return ret;
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "sort");
+	if (ret == -EINVAL)
+		return ret;
+
+	p = xbc_node_find_value(hnode, "size", NULL);
+	if (p)
+		append_printf(&buf, end, ":size=%s", p);
+
+	p = xbc_node_find_value(hnode, "name", NULL);
+	if (p)
+		append_printf(&buf, end, ":name=%s", p);
+
+	node = xbc_node_find_subkey(hnode, "var");
+	if (node) {
+		xbc_node_for_each_key_value(node, knode, p) {
+			/* Expression must not include spaces. */
+			append_printf(&buf, end, ":%s=",
+				      xbc_node_get_data(knode));
+			append_str_nospace(&buf, end, p);
+		}
+	}
+
+	/* Histogram control attributes (mutual exclusive) */
+	if (xbc_node_find_value(hnode, "pause", NULL))
+		append_printf(&buf, end, ":pause");
+	else if (xbc_node_find_value(hnode, "continue", NULL))
+		append_printf(&buf, end, ":continue");
+	else if (xbc_node_find_value(hnode, "clear", NULL))
+		append_printf(&buf, end, ":clear");
+
+	/* Histogram handler and actions */
+	node = xbc_node_find_subkey(hnode, "onmax");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
+		return -EINVAL;
+	node = xbc_node_find_subkey(hnode, "onchange");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
+		return -EINVAL;
+	node = xbc_node_find_subkey(hnode, "onmatch");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "event") < 0)
+		return -EINVAL;
+
+	p = xbc_node_find_value(hnode, "filter", NULL);
+	if (p)
+		append_printf(&buf, end, " if %s", p);
+
+	if (buf == end) {
+		pr_err("hist exceeds the max command length.\n");
+		return -E2BIG;
+	}
+
+	return 0;
+}
+
+static void __init
+trace_boot_init_histograms(struct trace_event_file *file,
+			   struct xbc_node *hnode, char *buf, size_t size)
+{
+	struct xbc_node *node;
+	const char *p;
+	char *tmp;
+
+	xbc_node_for_each_subkey(hnode, node) {
+		p = xbc_node_get_data(node);
+		if (!isdigit(p[0]))
+			continue;
+		/* All digit started node should be instances. */
+		if (trace_boot_compose_hist_cmd(node, buf, size) == 0) {
+			tmp = kstrdup(buf, GFP_KERNEL);
+			if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply hist trigger: %s\n", tmp);
+			kfree(tmp);
+		}
+	}
+
+	if (xbc_node_find_subkey(hnode, "keys")) {
+		if (trace_boot_compose_hist_cmd(hnode, buf, size) == 0) {
+			tmp = kstrdup(buf, GFP_KERNEL);
+			if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply hist trigger: %s\n", tmp);
+			kfree(tmp);
+		}
+	}
+}
+#else
+static void __init
+trace_boot_init_histograms(struct trace_event_file *file,
+			   struct xbc_node *hnode, char *buf, size_t size)
+{
+	/* do nothing */
+}
+#endif
+
 static void __init
 trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
 			  struct xbc_node *enode)
@@ -205,12 +488,18 @@ trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
 			pr_err("Failed to apply filter: %s\n", buf);
 	}
 
-	xbc_node_for_each_array_value(enode, "actions", anode, p) {
-		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
-			pr_err("action string is too long: %s\n", p);
-		else if (trigger_process_regex(file, buf) < 0)
-			pr_err("Failed to apply an action: %s\n", buf);
-	}
+	if (IS_ENABLED(CONFIG_HIST_TRIGGERS)) {
+		xbc_node_for_each_array_value(enode, "actions", anode, p) {
+			if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
+				pr_err("action string is too long: %s\n", p);
+			else if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply an action: %s\n", p);
+		}
+		anode = xbc_node_find_subkey(enode, "hist");
+		if (anode)
+			trace_boot_init_histograms(file, anode, buf, ARRAY_SIZE(buf));
+	} else if (xbc_node_find_value(enode, "actions", NULL))
+		pr_err("Failed to apply event actions because CONFIG_HIST_TRIGGERS is not set.\n");
 
 	if (xbc_node_find_value(enode, "enable", NULL)) {
 		if (trace_event_enable_disable(file, 1, 0) < 0)
@@ -228,18 +517,18 @@ trace_boot_init_events(struct trace_array *tr, struct xbc_node *node)
 	bool enable, enable_all = false;
 	const char *data;
 
-	node = xbc_node_find_child(node, "event");
+	node = xbc_node_find_subkey(node, "event");
 	if (!node)
 		return;
 	/* per-event key starts with "event.GROUP.EVENT" */
-	xbc_node_for_each_child(node, gnode) {
+	xbc_node_for_each_subkey(node, gnode) {
 		data = xbc_node_get_data(gnode);
 		if (!strcmp(data, "enable")) {
 			enable_all = true;
 			continue;
 		}
 		enable = false;
-		xbc_node_for_each_child(gnode, enode) {
+		xbc_node_for_each_subkey(gnode, enode) {
 			data = xbc_node_get_data(enode);
 			if (!strcmp(data, "enable")) {
 				enable = true;
@@ -331,11 +620,11 @@ trace_boot_init_instances(struct xbc_node *node)
 	struct trace_array *tr;
 	const char *p;
 
-	node = xbc_node_find_child(node, "instance");
+	node = xbc_node_find_subkey(node, "instance");
 	if (!node)
 		return;
 
-	xbc_node_for_each_child(node, inode) {
+	xbc_node_for_each_subkey(node, inode) {
 		p = xbc_node_get_data(inode);
 		if (!p || *p == '\0')
 			continue;