[PATCH 2/4] perf tools: Add trace event debugfs stream reader

[Frederic Weisbecker]

From: Steven Rostedt <rostedt@xxxxxxxxxxx>

Add util/trace-event-read.c which handles trace events informations
reading.

This file is a rename of the trace-read.c file from the trace-cmd tools,
written by Steven Rostedt and Josh Triplett, originated from the git
tree:

git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git

This is a perf tools integration.

[fweisbec@xxxxxxxxx: various changes for perf tools integration]

Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxx>
Cc: Zhaolei <zhaolei@xxxxxxxxxxxxxx>
Cc: Li Zefan <lizf@xxxxxxxxxxxxxx>
Cc: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Tom Zanussi <tzanussi@xxxxxxxxx>
---
 tools/perf/util/trace-event-read.c |  508 ++++++++++++++++++++++++++++++++++++
 1 files changed, 508 insertions(+), 0 deletions(-)
 create mode 100644 tools/perf/util/trace-event-read.c

diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
new file mode 100644
index 0000000..1dac301
--- /dev/null
+++ b/tools/perf/util/trace-event-read.c
@@ -0,0 +1,508 @@
+/*
+ * Copyright (C) 2009, Steven Rostedt <srostedt@xxxxxxxxxx>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License (not later!)
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#define _LARGEFILE64_SOURCE
+
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <pthread.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "util.h"
+#include "trace-event.h"
+
+static int input_fd;
+
+static int read_page;
+
+int file_bigendian;
+int host_bigendian;
+static int long_size;
+
+static unsigned long	page_size;
+
+static int read_or_die(void *data, int size)
+{
+	int r;
+
+	r = read(input_fd, data, size);
+	if (r != size)
+		die("reading input file (size expected=%d received=%d)",
+		    size, r);
+	return r;
+}
+
+static unsigned int read4(void)
+{
+	unsigned int data;
+
+	read_or_die(&data, 4);
+	return __data2host4(data);
+}
+
+static unsigned long long read8(void)
+{
+	unsigned long long data;
+
+	read_or_die(&data, 8);
+	return __data2host8(data);
+}
+
+static char *read_string(void)
+{
+	char buf[BUFSIZ];
+	char *str = NULL;
+	int size = 0;
+	int i;
+	int r;
+
+	for (;;) {
+		r = read(input_fd, buf, BUFSIZ);
+		if (r < 0)
+			die("reading input file");
+
+		if (!r)
+			die("no data");
+
+		for (i = 0; i < r; i++) {
+			if (!buf[i])
+				break;
+		}
+		if (i < r)
+			break;
+
+		if (str) {
+			size += BUFSIZ;
+			str = realloc(str, size);
+			if (!str)
+				die("malloc of size %d", size);
+			memcpy(str + (size - BUFSIZ), buf, BUFSIZ);
+		} else {
+			size = BUFSIZ;
+			str = malloc_or_die(size);
+			memcpy(str, buf, size);
+		}
+	}
+
+	/* move the file descriptor to the end of the string */
+	r = lseek(input_fd, -(r - (i+1)), SEEK_CUR);
+	if (r < 0)
+		die("lseek");
+
+	if (str) {
+		size += i;
+		str = realloc(str, size);
+		if (!str)
+			die("malloc of size %d", size);
+		memcpy(str + (size - i), buf, i);
+	} else {
+		size = i;
+		str = malloc_or_die(i);
+		memcpy(str, buf, i);
+	}
+
+	return str;
+}
+
+static void read_proc_kallsyms(void)
+{
+	unsigned int size;
+	char *buf;
+
+	size = read4();
+	if (!size)
+		return;
+
+	buf = malloc_or_die(size);
+	read_or_die(buf, size);
+
+	parse_proc_kallsyms(buf, size);
+
+	free(buf);
+}
+
+static void read_ftrace_printk(void)
+{
+	unsigned int size;
+	char *buf;
+
+	size = read4();
+	if (!size)
+		return;
+
+	buf = malloc_or_die(size);
+	read_or_die(buf, size);
+
+	parse_ftrace_printk(buf, size);
+
+	free(buf);
+}
+
+static void read_header_files(void)
+{
+	unsigned long long size;
+	char *header_page;
+	char *header_event;
+	char buf[BUFSIZ];
+
+	read_or_die(buf, 12);
+
+	if (memcmp(buf, "header_page", 12) != 0)
+		die("did not read header page");
+
+	size = read8();
+	header_page = malloc_or_die(size);
+	read_or_die(header_page, size);
+	parse_header_page(header_page, size);
+	free(header_page);
+
+	/*
+	 * The size field in the page is of type long,
+	 * use that instead, since it represents the kernel.
+	 */
+	long_size = header_page_size_size;
+
+	read_or_die(buf, 13);
+	if (memcmp(buf, "header_event", 13) != 0)
+		die("did not read header event");
+
+	size = read8();
+	header_event = malloc_or_die(size);
+	read_or_die(header_event, size);
+	free(header_event);
+}
+
+static void read_ftrace_file(unsigned long long size)
+{
+	char *buf;
+
+	buf = malloc_or_die(size);
+	read_or_die(buf, size);
+	parse_ftrace_file(buf, size);
+	free(buf);
+}
+
+static void read_event_file(char *sys, unsigned long long size)
+{
+	char *buf;
+
+	buf = malloc_or_die(size);
+	read_or_die(buf, size);
+	parse_event_file(buf, size, sys);
+	free(buf);
+}
+
+static void read_ftrace_files(void)
+{
+	unsigned long long size;
+	int count;
+	int i;
+
+	count = read4();
+
+	for (i = 0; i < count; i++) {
+		size = read8();
+		read_ftrace_file(size);
+	}
+}
+
+static void read_event_files(void)
+{
+	unsigned long long size;
+	char *sys;
+	int systems;
+	int count;
+	int i,x;
+
+	systems = read4();
+
+	for (i = 0; i < systems; i++) {
+		sys = read_string();
+
+		count = read4();
+		for (x=0; x < count; x++) {
+			size = read8();
+			read_event_file(sys, size);
+		}
+	}
+}
+
+struct cpu_data {
+	unsigned long long	offset;
+	unsigned long long	size;
+	unsigned long long	timestamp;
+	struct record		*next;
+	char			*page;
+	int			cpu;
+	int			index;
+	int			page_size;
+};
+
+static struct cpu_data *cpu_data;
+
+static void update_cpu_data_index(int cpu)
+{
+	cpu_data[cpu].offset += page_size;
+	cpu_data[cpu].size -= page_size;
+	cpu_data[cpu].index = 0;
+}
+
+static void get_next_page(int cpu)
+{
+	off64_t save_seek;
+	off64_t ret;
+
+	if (!cpu_data[cpu].page)
+		return;
+
+	if (read_page) {
+		if (cpu_data[cpu].size <= page_size) {
+			free(cpu_data[cpu].page);
+			cpu_data[cpu].page = NULL;
+			return;
+		}
+
+		update_cpu_data_index(cpu);
+
+		/* other parts of the code may expect the pointer to not move */
+		save_seek = lseek64(input_fd, 0, SEEK_CUR);
+
+		ret = lseek64(input_fd, cpu_data[cpu].offset, SEEK_SET);
+		if (ret < 0)
+			die("failed to lseek");
+		ret = read(input_fd, cpu_data[cpu].page, page_size);
+		if (ret < 0)
+			die("failed to read page");
+
+		/* reset the file pointer back */
+		lseek64(input_fd, save_seek, SEEK_SET);
+
+		return;
+	}
+
+	munmap(cpu_data[cpu].page, page_size);
+	cpu_data[cpu].page = NULL;
+
+	if (cpu_data[cpu].size <= page_size)
+		return;
+
+	update_cpu_data_index(cpu);
+
+	cpu_data[cpu].page = mmap(NULL, page_size, PROT_READ, MAP_PRIVATE,
+				  input_fd, cpu_data[cpu].offset);
+	if (cpu_data[cpu].page == MAP_FAILED)
+		die("failed to mmap cpu %d at offset 0x%llx",
+		    cpu, cpu_data[cpu].offset);
+}
+
+static unsigned int type_len4host(unsigned int type_len_ts)
+{
+	if (file_bigendian)
+		return (type_len_ts >> 27) & ((1 << 5) - 1);
+	else
+		return type_len_ts & ((1 << 5) - 1);
+}
+
+static unsigned int ts4host(unsigned int type_len_ts)
+{
+	if (file_bigendian)
+		return type_len_ts & ((1 << 27) - 1);
+	else
+		return type_len_ts >> 5;
+}
+
+static int calc_index(void *ptr, int cpu)
+{
+	return (unsigned long)ptr - (unsigned long)cpu_data[cpu].page;
+}
+
+struct record *trace_peek_data(int cpu)
+{
+	struct record *data;
+	void *page = cpu_data[cpu].page;
+	int idx = cpu_data[cpu].index;
+	void *ptr = page + idx;
+	unsigned long long extend;
+	unsigned int type_len_ts;
+	unsigned int type_len;
+	unsigned int delta;
+	unsigned int length = 0;
+
+	if (cpu_data[cpu].next)
+		return cpu_data[cpu].next;
+
+	if (!page)
+		return NULL;
+
+	if (!idx) {
+		/* FIXME: handle header page */
+		if (header_page_ts_size != 8)
+			die("expected a long long type for timestamp");
+		cpu_data[cpu].timestamp = data2host8(ptr);
+		ptr += 8;
+		switch (header_page_size_size) {
+		case 4:
+			cpu_data[cpu].page_size = data2host4(ptr);
+			ptr += 4;
+			break;
+		case 8:
+			cpu_data[cpu].page_size = data2host8(ptr);
+			ptr += 8;
+			break;
+		default:
+			die("bad long size");
+		}
+		ptr = cpu_data[cpu].page + header_page_data_offset;
+	}
+
+read_again:
+	idx = calc_index(ptr, cpu);
+
+	if (idx >= cpu_data[cpu].page_size) {
+		get_next_page(cpu);
+		return trace_peek_data(cpu);
+	}
+
+	type_len_ts = data2host4(ptr);
+	ptr += 4;
+
+	type_len = type_len4host(type_len_ts);
+	delta = ts4host(type_len_ts);
+
+	switch (type_len) {
+	case RINGBUF_TYPE_PADDING:
+		if (!delta)
+			die("error, hit unexpected end of page");
+		length = data2host4(ptr);
+		ptr += 4;
+		length *= 4;
+		ptr += length;
+		goto read_again;
+
+	case RINGBUF_TYPE_TIME_EXTEND:
+		extend = data2host4(ptr);
+		ptr += 4;
+		extend <<= TS_SHIFT;
+		extend += delta;
+		cpu_data[cpu].timestamp += extend;
+		goto read_again;
+
+	case RINGBUF_TYPE_TIME_STAMP:
+		ptr += 12;
+		break;
+	case 0:
+		length = data2host4(ptr);
+		ptr += 4;
+		die("here! length=%d", length);
+		break;
+	default:
+		length = type_len * 4;
+		break;
+	}
+
+	cpu_data[cpu].timestamp += delta;
+
+	data = malloc_or_die(sizeof(*data));
+	memset(data, 0, sizeof(*data));
+
+	data->ts = cpu_data[cpu].timestamp;
+	data->size = length;
+	data->data = ptr;
+	ptr += length;
+
+	cpu_data[cpu].index = calc_index(ptr, cpu);
+	cpu_data[cpu].next = data;
+
+	return data;
+}
+
+struct record *trace_read_data(int cpu)
+{
+	struct record *data;
+
+	data = trace_peek_data(cpu);
+	cpu_data[cpu].next = NULL;
+
+	return data;
+}
+
+void trace_report (void)
+{
+	const char *input_file = "trace.info";
+	char buf[BUFSIZ];
+	char test[] = { 23, 8, 68 };
+	char *version;
+	int show_funcs = 0;
+	int show_printk = 0;
+
+	input_fd = open(input_file, O_RDONLY);
+	if (input_fd < 0)
+		die("opening '%s'\n", input_file);
+
+	read_or_die(buf, 3);
+	if (memcmp(buf, test, 3) != 0)
+		die("not an trace data file");
+
+	read_or_die(buf, 7);
+	if (memcmp(buf, "tracing", 7) != 0)
+		die("not a trace file (missing tracing)");
+
+	version = read_string();
+	printf("version = %s\n", version);
+	free(version);
+
+	read_or_die(buf, 1);
+	file_bigendian = buf[0];
+	host_bigendian = bigendian();
+
+	read_or_die(buf, 1);
+	long_size = buf[0];
+
+	page_size = read4();
+
+	read_header_files();
+
+	read_ftrace_files();
+	read_event_files();
+	read_proc_kallsyms();
+	read_ftrace_printk();
+
+	if (show_funcs) {
+		print_funcs();
+		return;
+	}
+	if (show_printk) {
+		print_printk();
+		return;
+	}
+
+	return;
+}
-- 
1.6.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/