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

From: Frederic Weisbecker
Date: Mon Aug 17 2009 - 10:18:29 EST


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

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