1 files changed, 397 insertions, 0 deletions
diff --git a/lib/trace-cmd/trace-ftrace.c b/lib/trace-cmd/trace-ftrace.c
new file mode 100644
index 00000000..f74f7c2e
--- /dev/null
+++ b/lib/trace-cmd/trace-ftrace.c
@@ -0,0 +1,397 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/param.h>
+
+#include "trace-cmd-private.h"
+
+struct tep_plugin_option trace_ftrace_options[] = {
+	{
+		.name = "tailprint",
+		.plugin_alias = "fgraph",
+		.description =
+		"Print function name at function exit in function graph",
+	},
+	{
+		.name = "depth",
+		.plugin_alias = "fgraph",
+		.description =
+		"Show the depth of each entry",
+	},
+	{
+		.name = NULL,
+	}
+};
+
+static struct tep_plugin_option *fgraph_tail = &trace_ftrace_options[0];
+static struct tep_plugin_option *fgraph_depth = &trace_ftrace_options[1];
+
+static int find_ret_event(struct tracecmd_ftrace *finfo, struct tep_handle *pevent)
+{
+	struct tep_event *event;
+
+	/* Store the func ret id and event for later use */
+	event = tep_find_event_by_name(pevent, "ftrace", "funcgraph_exit");
+	if (!event)
+		return -1;
+
+	finfo->fgraph_ret_id = event->id;
+	finfo->fgraph_ret_event = event;
+	return 0;
+}
+
+#define ret_event_check(finfo, pevent)					\
+	do {								\
+		if (!finfo->fgraph_ret_event && find_ret_event(finfo, pevent) < 0) \
+			return -1;					\
+	} while (0)
+
+static int function_handler(struct trace_seq *s, struct tep_record *record,
+			    struct tep_event *event, void *context)
+{
+	struct tep_handle *pevent = event->tep;
+	unsigned long long function;
+	const char *func;
+
+	if (tep_get_field_val(s, event, "ip", record, &function, 1))
+		return trace_seq_putc(s, '!');
+
+	func = tep_find_function(pevent, function);
+	if (func)
+		trace_seq_printf(s, "%s <-- ", func);
+	else
+		trace_seq_printf(s, "0x%llx", function);
+
+	if (tep_get_field_val(s, event, "parent_ip", record, &function, 1))
+		return trace_seq_putc(s, '!');
+
+	func = tep_find_function(pevent, function);
+	if (func)
+		trace_seq_printf(s, "%s", func);
+	else
+		trace_seq_printf(s, "0x%llx", function);
+
+	return 0;
+}
+
+#define TRACE_GRAPH_INDENT		2
+
+static struct tep_record *
+get_return_for_leaf(struct trace_seq *s, int cpu, int cur_pid,
+		    unsigned long long cur_func, struct tep_record *next,
+		    struct tracecmd_ftrace *finfo)
+{
+	unsigned long long val;
+	unsigned long long type;
+	unsigned long long pid;
+
+	/* Searching a common field, can use any event */
+	if (tep_get_common_field_val(s, finfo->fgraph_ret_event, "common_type", next, &type, 1))
+		return NULL;
+
+	if (type != finfo->fgraph_ret_id)
+		return NULL;
+
+	if (tep_get_common_field_val(s, finfo->fgraph_ret_event, "common_pid", next, &pid, 1))
+		return NULL;
+
+	if (cur_pid != pid)
+		return NULL;
+
+	/* We aleady know this is a funcgraph_ret_event */
+	if (tep_get_field_val(s, finfo->fgraph_ret_event, "func", next, &val, 1))
+		return NULL;
+
+	if (cur_func != val)
+		return NULL;
+
+	/* this is a leaf, now advance the iterator */
+	return tracecmd_read_data(tracecmd_curr_thread_handle, cpu);
+}
+
+/* Signal a overhead of time execution to the output */
+static void print_graph_overhead(struct trace_seq *s,
+				 unsigned long long duration)
+{
+	/* Non nested entry or return */
+	if (duration == ~0ULL)
+		return (void)trace_seq_printf(s, "  ");
+
+	/* Duration exceeded 1 sec */
+	if (duration > 1000000000ULL)
+		return (void)trace_seq_printf(s, "$ ");
+
+	/* Duration exceeded 1000 usecs */
+	if (duration > 1000000ULL)
+		return (void)trace_seq_printf(s, "# ");
+
+	/* Duration exceeded 100 usecs */
+	if (duration > 100000ULL)
+		return (void)trace_seq_printf(s, "! ");
+
+	/* Duration exceeded 10 usecs */
+	if (duration > 10000ULL)
+		return (void)trace_seq_printf(s, "+ ");
+
+	trace_seq_printf(s, "  ");
+}
+
+static void print_graph_duration(struct trace_seq *s, unsigned long long duration)
+{
+	unsigned long usecs = duration / 1000;
+	unsigned long nsecs_rem = duration % 1000;
+	/* log10(ULONG_MAX) + '\0' */
+	char msecs_str[21];
+	char nsecs_str[5];
+	int len;
+	int i;
+
+	sprintf(msecs_str, "%lu", usecs);
+
+	/* Print msecs */
+	len = s->len;
+	trace_seq_printf(s, "%lu", usecs);
+
+	/* Print nsecs (we don't want to exceed 7 numbers) */
+	if ((s->len - len) < 7) {
+		snprintf(nsecs_str, MIN(sizeof(nsecs_str), 8 - len), "%03lu", nsecs_rem);
+		trace_seq_printf(s, ".%s", nsecs_str);
+	}
+
+	len = s->len - len;
+
+	trace_seq_puts(s, " us ");
+
+	/* Print remaining spaces to fit the row's width */
+	for (i = len; i < 7; i++)
+		trace_seq_putc(s, ' ');
+
+	trace_seq_puts(s, "|  ");
+}
+
+static int
+print_graph_entry_leaf(struct trace_seq *s,
+		       struct tep_event *event,
+		       struct tep_record *record,
+		       struct tep_record *ret_rec,
+		       struct tracecmd_ftrace *finfo)
+{
+	struct tep_handle *pevent = event->tep;
+	unsigned long long rettime, calltime;
+	unsigned long long duration, depth;
+	unsigned long long val;
+	const char *func;
+	int ret;
+	int i;
+
+	if (tep_get_field_val(s, finfo->fgraph_ret_event, "rettime", ret_rec, &rettime, 1))
+		return trace_seq_putc(s, '!');
+
+	if (tep_get_field_val(s, finfo->fgraph_ret_event, "calltime", ret_rec, &calltime, 1))
+		return trace_seq_putc(s, '!');
+
+	duration = rettime - calltime;
+
+	/* Overhead */
+	print_graph_overhead(s, duration);
+
+	/* Duration */
+	print_graph_duration(s, duration);
+
+	if (tep_get_field_val(s, event, "depth", record, &depth, 1))
+		return trace_seq_putc(s, '!');
+
+	/* Function */
+	for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
+		trace_seq_putc(s, ' ');
+
+	if (tep_get_field_val(s, event, "func", record, &val, 1))
+		return trace_seq_putc(s, '!');
+	func = tep_find_function(pevent, val);
+
+	if (func)
+		ret = trace_seq_printf(s, "%s();", func);
+	else
+		ret = trace_seq_printf(s, "%llx();", val);
+
+	if (ret && fgraph_depth->set)
+		ret = trace_seq_printf(s, " (%lld)", depth);
+
+	return ret;
+}
+
+static int print_graph_nested(struct trace_seq *s,
+			      struct tep_event *event,
+			      struct tep_record *record)
+{
+	struct tep_handle *pevent = event->tep;
+	unsigned long long depth;
+	unsigned long long val;
+	const char *func;
+	int ret;
+	int i;
+
+	/* No overhead */
+	print_graph_overhead(s, -1);
+
+	/* No time */
+	trace_seq_puts(s, "           |  ");
+
+	if (tep_get_field_val(s, event, "depth", record, &depth, 1))
+		return trace_seq_putc(s, '!');
+
+	/* Function */
+	for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
+		trace_seq_putc(s, ' ');
+
+	if (tep_get_field_val(s, event, "func", record, &val, 1))
+		return trace_seq_putc(s, '!');
+
+	func = tep_find_function(pevent, val);
+
+	if (func)
+		ret = trace_seq_printf(s, "%s() {", func);
+	else
+		ret = trace_seq_printf(s, "%llx() {", val);
+
+	if (ret && fgraph_depth->set)
+		ret = trace_seq_printf(s, " (%lld)", depth);
+
+	return ret;
+}
+
+static int
+fgraph_ent_handler(struct trace_seq *s, struct tep_record *record,
+		   struct tep_event *event, void *context)
+{
+	struct tracecmd_ftrace *finfo = context;
+	struct tep_record *rec;
+	unsigned long long val, pid;
+	int cpu;
+
+	ret_event_check(finfo, event->tep);
+
+	if (tep_get_common_field_val(s, event, "common_pid", record, &pid, 1))
+		return trace_seq_putc(s, '!');
+
+	if (tep_get_field_val(s, event, "func", record, &val, 1))
+		return trace_seq_putc(s, '!');
+
+	rec = tracecmd_peek_next_data(tracecmd_curr_thread_handle, &cpu);
+	if (rec)
+		rec = get_return_for_leaf(s, cpu, pid, val, rec, finfo);
+
+	if (rec) {
+		/*
+		 * If this is a leaf function, then get_return_for_leaf
+		 * returns the return of the function
+		 */
+		print_graph_entry_leaf(s, event, record, rec, finfo);
+		tracecmd_free_record(rec);
+	} else
+		print_graph_nested(s, event, record);
+
+	return 0;
+}
+
+static int
+fgraph_ret_handler(struct trace_seq *s, struct tep_record *record,
+		   struct tep_event *event, void *context)
+{
+	struct tracecmd_ftrace *finfo = context;
+	unsigned long long rettime, calltime;
+	unsigned long long duration, depth;
+	unsigned long long val;
+	const char *func;
+	int i;
+
+	ret_event_check(finfo, event->tep);
+
+	if (tep_get_field_val(s, event, "rettime", record, &rettime, 1))
+		return trace_seq_putc(s, '!');
+
+	if (tep_get_field_val(s, event, "calltime", record, &calltime, 1))
+		return trace_seq_putc(s, '!');
+
+	duration = rettime - calltime;
+
+	/* Overhead */
+	print_graph_overhead(s, duration);
+
+	/* Duration */
+	print_graph_duration(s, duration);
+
+	if (tep_get_field_val(s, event, "depth", record, &depth, 1))
+		return trace_seq_putc(s, '!');
+
+	/* Function */
+	for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
+		trace_seq_putc(s, ' ');
+
+	trace_seq_putc(s, '}');
+
+	if (fgraph_tail->set) {
+		if (tep_get_field_val(s, event, "func", record, &val, 0))
+			return 0;
+		func = tep_find_function(event->tep, val);
+		if (!func)
+			return 0;
+		trace_seq_printf(s, " /* %s */", func);
+	}
+
+	if (fgraph_depth->set)
+		trace_seq_printf(s, " (%lld)", depth);
+
+	return 0;
+}
+
+/**
+ * tracecmd_ftrace_load_options - load the ftrace options
+ *
+ * This routine is used for trace-cmd list, to load the builtin
+ * ftrace options in order to list them. As the list command does
+ * not load a trace.dat file where this would normally be loaded.
+ */
+void tracecmd_ftrace_load_options(void)
+{
+	tep_plugin_add_options("ftrace", trace_ftrace_options);
+}
+
+int tracecmd_ftrace_overrides(struct tracecmd_input *handle,
+	struct tracecmd_ftrace *finfo)
+{
+	struct tep_handle *pevent;
+	struct tep_event *event;
+
+	finfo->handle = handle;
+
+	pevent = tracecmd_get_tep(handle);
+
+	tep_register_event_handler(pevent, -1, "ftrace", "function",
+				      function_handler, NULL);
+
+	tep_register_event_handler(pevent, -1, "ftrace", "funcgraph_entry",
+				      fgraph_ent_handler, finfo);
+
+	tep_register_event_handler(pevent, -1, "ftrace", "funcgraph_exit",
+				      fgraph_ret_handler, finfo);
+
+	tep_plugin_add_options("ftrace", trace_ftrace_options);
+
+	/* Store the func ret id and event for later use */
+	event = tep_find_event_by_name(pevent, "ftrace", "funcgraph_exit");
+	if (!event)
+		return 0;
+
+	finfo->long_size = tracecmd_long_size(handle);
+
+	finfo->fgraph_ret_id = event->id;
+	finfo->fgraph_ret_event = event;
+
+	return 0;
+}