crash/extensions/trace.c
Valentin Schneider f1d5078a48 extensions/trace: Rename ring_buffer to trace_buffer
This renaming is present from Linux v5.6 upwards, and was introduced by
commit:

  13292494379f ("tracing: Make struct ring_buffer less ambiguous")

Rename the internal references from ring_buffer to trace_buffer. Backwards
compatibility with older kernels is provided by checking whether struct
trace_buffer has a buffer field of type struct ring buffer - should that
not be the case, the newer naming scheme is used instead.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
2020-10-12 11:26:15 +09:00

2593 lines
58 KiB
C

/*
* trace extension module for crash
*
* Copyright (C) 2009, 2010 FUJITSU LIMITED
* Author: Lai Jiangshan <laijs@cn.fujitsu.com>
*
* 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; either version 2, or (at your option)
* any later version.
*/
#define _GNU_SOURCE
#include "defs.h"
#include <stdio.h>
#include <ctype.h>
#include <setjmp.h>
#include <stdlib.h>
static int verbose = 0;
static int nr_cpu_ids;
/*
* lockless ring_buffer and old non-lockless ring_buffer are both supported.
*/
static int lockless_ring_buffer;
static int per_cpu_buffer_sizes;
/*
* global and encapsulated current_trace are both supported
*/
static int encapsulated_current_trace;
/*
* array_buffer (trace_buffer pre v5.6) is supported
*/
static int array_buffer_available;
/*
* max_buffer is supported
*/
static int max_buffer_available;
/*
* multiple trace instances are supported
*/
static int multiple_instances_available;
/*
* buffer_page has "real_end"
*/
static int buffer_page_real_end_available;
#define koffset(struct, member) struct##_##member##_offset
static int koffset(trace_array, current_trace);
static int koffset(trace_array, array_buffer);
static int koffset(trace_array, max_buffer);
static int koffset(array_buffer, buffer);
static int koffset(trace_array, buffer);
static int koffset(tracer, name);
static int koffset(trace_buffer, pages);
static int koffset(trace_buffer, flags);
static int koffset(trace_buffer, cpus);
static int koffset(trace_buffer, buffers);
static int koffset(ring_buffer_per_cpu, cpu);
static int koffset(ring_buffer_per_cpu, pages);
static int koffset(ring_buffer_per_cpu, nr_pages);
static int koffset(ring_buffer_per_cpu, head_page);
static int koffset(ring_buffer_per_cpu, tail_page);
static int koffset(ring_buffer_per_cpu, commit_page);
static int koffset(ring_buffer_per_cpu, reader_page);
static int koffset(ring_buffer_per_cpu, overrun);
static int koffset(ring_buffer_per_cpu, entries);
static int koffset(buffer_page, read);
static int koffset(buffer_page, list);
static int koffset(buffer_page, page);
static int koffset(buffer_page, real_end);
static int koffset(list_head, next);
static int koffset(ftrace_event_call, list);
static int koffset(ftrace_event_field, link);
static int koffset(ftrace_event_field, name);
static int koffset(ftrace_event_field, type);
static int koffset(ftrace_event_field, offset);
static int koffset(ftrace_event_field, size);
static int koffset(ftrace_event_field, is_signed);
static int koffset(trace_array, name);
static int koffset(POINTER_SYM, POINTER) = 0;
struct ring_buffer_per_cpu {
ulong kaddr;
ulong head_page;
ulong tail_page;
ulong commit_page;
ulong reader_page;
ulong real_head_page;
int head_page_index;
unsigned long nr_pages;
ulong *pages;
ulong *linear_pages;
int nr_linear_pages;
ulong overrun;
ulong entries;
};
static ulong global_trace;
static ulong max_tr_trace;
struct trace_instance {
char name[NAME_MAX + 1];
ulong array_buffer;
ulong max_buffer;
ulong trace_buffer;
unsigned pages;
struct ring_buffer_per_cpu *buffers;
ulong max_tr_ring_buffer;
unsigned max_tr_pages;
struct ring_buffer_per_cpu *max_tr_buffers;
};
static ulong ftrace_trace_arrays;
static struct trace_instance global_trace_instance;
static struct trace_instance *trace_instances = NULL;
static int instance_count;
static ulong ftrace_events;
static ulong current_trace;
static const char *current_tracer_name;
static void ftrace_destroy_event_types(void);
static int ftrace_init_event_types(void);
/* at = ((struct *)ptr)->member */
#define read_value(at, ptr, struct, member) \
do { \
if (!readmem(ptr + koffset(struct, member), KVADDR, \
&at, sizeof(at), #struct "'s " #member, \
RETURN_ON_ERROR)) \
goto out_fail;\
} while (0)
/* Remove the "const" qualifiers for ptr */
#define free(ptr) free((void *)(ptr))
static int write_and_check(int fd, void *data, size_t size)
{
size_t tot = 0;
size_t w;
do {
w = write(fd, data, size - tot);
tot += w;
if (w <= 0)
return -1;
} while (tot != size);
return 0;
}
#ifndef PATH_MAX
#define PATH_MAX 4096
#endif
static int init_offsets(void)
{
#define check_offset(struct, member) do { \
if (koffset(struct, member) < 0) { \
fprintf(fp, "failed to init the offset, struct:"\
#struct ", member:" #member); \
fprintf(fp, "\n"); \
return -1; \
} \
} while (0)
#define init_offset(struct, member) do { \
koffset(struct, member) = MEMBER_OFFSET(#struct, #member); \
check_offset(struct, member); \
} while (0)
#define init_offset_alternative(struct, member, alt_struct, alt_member) do { \
koffset(struct, member) = MEMBER_OFFSET(#alt_struct, #alt_member); \
check_offset(struct, member); \
} while (0)
if (encapsulated_current_trace)
init_offset(trace_array, current_trace);
if (array_buffer_available) {
if (MEMBER_EXISTS("trace_array", "array_buffer")) {
init_offset(trace_array, array_buffer);
init_offset(array_buffer, buffer);
} else {
init_offset_alternative(trace_array, array_buffer,
trace_array, trace_buffer);
init_offset_alternative(array_buffer, buffer,
trace_buffer, buffer);
}
if (max_buffer_available)
init_offset(trace_array, max_buffer);
} else {
init_offset(trace_array, buffer);
}
init_offset(tracer, name);
if (MEMBER_EXISTS("ring_buffer_per_cpu", "nr_pages")) {
per_cpu_buffer_sizes = 1;
if (verbose)
fprintf(fp, "per cpu buffer sizes\n");
}
if (machine_type("PPC64") && kernel_symbol_exists(".ring_buffer_read"))
gdb_set_crash_scope(symbol_value(".ring_buffer_read"), ".ring_buffer_read");
else if (kernel_symbol_exists("ring_buffer_read"))
gdb_set_crash_scope(symbol_value("ring_buffer_read"), "ring_buffer_read");
if (STREQ(MEMBER_TYPE_NAME("trace_buffer", "buffer"), "ring_buffer")) {
if (!per_cpu_buffer_sizes)
init_offset_alternative(trace_buffer, pages, ring_buffer, pages);
init_offset_alternative(trace_buffer, flags, ring_buffer, flags);
init_offset_alternative(trace_buffer, cpus, ring_buffer, cpus);
init_offset_alternative(trace_buffer, buffers, ring_buffer, buffers);
} else {
if (!per_cpu_buffer_sizes)
init_offset(trace_buffer, pages);
init_offset(trace_buffer, flags);
init_offset(trace_buffer, cpus);
init_offset(trace_buffer, buffers);
}
if (MEMBER_SIZE("ring_buffer_per_cpu", "pages") == sizeof(ulong)) {
lockless_ring_buffer = 1;
if (verbose)
fprintf(fp, "lockless\n");
}
if (per_cpu_buffer_sizes)
init_offset(ring_buffer_per_cpu, nr_pages);
init_offset(ring_buffer_per_cpu, cpu);
init_offset(ring_buffer_per_cpu, pages);
init_offset(ring_buffer_per_cpu, head_page);
init_offset(ring_buffer_per_cpu, tail_page);
init_offset(ring_buffer_per_cpu, commit_page);
init_offset(ring_buffer_per_cpu, reader_page);
init_offset(ring_buffer_per_cpu, overrun);
init_offset(ring_buffer_per_cpu, entries);
init_offset(buffer_page, read);
init_offset(buffer_page, list);
init_offset(buffer_page, page);
init_offset(buffer_page, real_end);
init_offset(list_head, next);
koffset(ftrace_event_call, list) = MAX(MEMBER_OFFSET("ftrace_event_call", "list"),
MEMBER_OFFSET("trace_event_call", "list"));
if (koffset(ftrace_event_call, list) < 0) {
fprintf(fp, "failed to init the offset, struct:[f]trace_event_call member:list)\n");
return -1; \
}
init_offset(ftrace_event_field, link);
init_offset(ftrace_event_field, name);
init_offset(ftrace_event_field, type);
init_offset(ftrace_event_field, offset);
init_offset(ftrace_event_field, size);
init_offset(ftrace_event_field, is_signed);
if (MEMBER_EXISTS("trace_array", "name"))
init_offset(trace_array, name);
return 0;
#undef init_offset
}
static void print_offsets(void)
{
if (!verbose)
return;
#define print_offset(struct, member) fprintf(fp, \
"koffset(" #struct ", " #member ") = %d\n", koffset(struct, member))
print_offset(trace_array, buffer);
print_offset(tracer, name);
print_offset(trace_buffer, pages);
print_offset(trace_buffer, flags);
print_offset(trace_buffer, cpus);
print_offset(trace_buffer, buffers);
print_offset(ring_buffer_per_cpu, cpu);
print_offset(ring_buffer_per_cpu, pages);
print_offset(ring_buffer_per_cpu, head_page);
print_offset(ring_buffer_per_cpu, tail_page);
print_offset(ring_buffer_per_cpu, commit_page);
print_offset(ring_buffer_per_cpu, reader_page);
print_offset(ring_buffer_per_cpu, overrun);
print_offset(ring_buffer_per_cpu, entries);
print_offset(buffer_page, read);
print_offset(buffer_page, list);
print_offset(buffer_page, page);
print_offset(buffer_page, real_end);
print_offset(list_head, next);
print_offset(ftrace_event_call, list);
print_offset(ftrace_event_field, link);
print_offset(ftrace_event_field, name);
print_offset(ftrace_event_field, type);
print_offset(ftrace_event_field, offset);
print_offset(ftrace_event_field, size);
print_offset(ftrace_event_field, is_signed);
#undef print_offset
}
static int buffer_page_has_data(ulong page)
{
uint end;
if (!buffer_page_real_end_available)
return 1;
/* Only write pages with data in it */
read_value(end, page, buffer_page, real_end);
return end;
out_fail:
return 0;
}
static int ftrace_init_pages(struct ring_buffer_per_cpu *cpu_buffer,
unsigned nr_pages)
{
unsigned j = 0, count = 0;
ulong head, page;
ulong real_head_page = cpu_buffer->head_page;
cpu_buffer->pages = calloc(sizeof(ulong), nr_pages);
if (cpu_buffer->pages == NULL)
return -1;
cpu_buffer->linear_pages = calloc(sizeof(ulong), nr_pages + 1);
if (cpu_buffer->linear_pages == NULL) {
return -1;
}
if (lockless_ring_buffer) {
read_value(head, cpu_buffer->kaddr, ring_buffer_per_cpu, pages);
cpu_buffer->pages[j++] = head - koffset(buffer_page, list);
} else
head = cpu_buffer->kaddr + koffset(ring_buffer_per_cpu, pages);
page = head;
for (;;) {
read_value(page, page, list_head, next);
if (page & 3) {
/* lockless_ring_buffer */
page &= ~3;
real_head_page = page - koffset(buffer_page, list);
}
if (j == nr_pages)
break;
if (page == head) {
error(INFO, "Num of pages is less than %d\n", nr_pages);
goto out_fail;
}
cpu_buffer->pages[j++] = page - koffset(buffer_page, list);
}
if (page != head) {
error(INFO, "Num of pages is larger than %d\n", nr_pages);
goto out_fail;
}
/* find head page and head_page_index */
cpu_buffer->real_head_page = real_head_page;
cpu_buffer->head_page_index = -1;
for (j = 0; j < nr_pages; j++) {
if (cpu_buffer->pages[j] == real_head_page) {
cpu_buffer->head_page_index = j;
break;
}
}
if (cpu_buffer->head_page_index == -1) {
error(INFO, "error for resolve head_page_index\n");
goto out_fail;
}
/* Setup linear pages */
if (buffer_page_has_data(cpu_buffer->reader_page))
cpu_buffer->linear_pages[count++] = cpu_buffer->reader_page;
if (cpu_buffer->reader_page == cpu_buffer->commit_page)
goto done;
j = cpu_buffer->head_page_index;
for (;;) {
cpu_buffer->linear_pages[count++] = cpu_buffer->pages[j];
if (cpu_buffer->pages[j] == cpu_buffer->commit_page)
break;
j++;
if (j == nr_pages)
j = 0;
if (j == cpu_buffer->head_page_index) {
/* cpu_buffer->commit_page may be corrupted */
break;
}
}
done:
cpu_buffer->nr_linear_pages = count;
return 0;
out_fail:
return -1;
}
static void ftrace_destroy_buffers(struct ring_buffer_per_cpu *buffers)
{
int i;
for (i = 0; i < nr_cpu_ids; i++) {
if (!buffers[i].kaddr)
continue;
free(buffers[i].pages);
free(buffers[i].linear_pages);
}
}
static int ftrace_init_buffers(struct ring_buffer_per_cpu *buffers,
ulong trace_buffer, unsigned pages)
{
int i;
ulong buffers_array;
read_value(buffers_array, trace_buffer, trace_buffer, buffers);
for (i = 0; i < nr_cpu_ids; i++) {
if (!readmem(buffers_array + sizeof(ulong) * i, KVADDR,
&buffers[i].kaddr, sizeof(ulong),
"ring_buffer's cpu buffer", RETURN_ON_ERROR))
goto out_fail;
if (!buffers[i].kaddr)
continue;
#define buffer_read_value(member) read_value(buffers[i].member, \
buffers[i].kaddr, ring_buffer_per_cpu, member)
buffer_read_value(head_page);
buffer_read_value(tail_page);
buffer_read_value(commit_page);
buffer_read_value(reader_page);
buffer_read_value(overrun);
buffer_read_value(entries);
if (per_cpu_buffer_sizes) {
if (MEMBER_SIZE("ring_buffer_per_cpu", "nr_pages") == sizeof(unsigned int)) {
unsigned int tmp_nr_pages;
read_value(tmp_nr_pages, buffers[i].kaddr, ring_buffer_per_cpu, nr_pages);
buffers[i].nr_pages = (unsigned long) tmp_nr_pages;
} else {
buffer_read_value(nr_pages);
}
pages = buffers[i].nr_pages;
} else
buffers[i].nr_pages = pages;
#undef buffer_read_value
if (ftrace_init_pages(buffers + i, pages) < 0)
goto out_fail;
if (verbose) {
fprintf(fp, "overrun=%lu\n", buffers[i].overrun);
fprintf(fp, "entries=%lu\n", buffers[i].entries);
}
}
return 0;
out_fail:
ftrace_destroy_buffers(buffers);
return -1;
}
static int ftrace_init_trace(struct trace_instance *ti, ulong instance_addr)
{
if (array_buffer_available) {
ti->array_buffer = instance_addr +
koffset(trace_array, array_buffer);
read_value(ti->trace_buffer, ti->array_buffer,
array_buffer, buffer);
if (max_buffer_available) {
ti->max_buffer = instance_addr +
koffset(trace_array, max_buffer);
read_value(ti->max_tr_ring_buffer, ti->max_buffer,
array_buffer, buffer);
}
} else {
read_value(ti->trace_buffer, instance_addr, trace_array, buffer);
read_value(ti->pages, ti->trace_buffer, trace_buffer, pages);
read_value(ti->max_tr_ring_buffer, max_tr_trace, trace_array, buffer);
if (ti->max_tr_ring_buffer)
read_value(ti->max_tr_pages, ti->max_tr_ring_buffer, trace_buffer, pages);
}
ti->buffers = calloc(sizeof(*ti->buffers), nr_cpu_ids);
if (ti->buffers == NULL)
goto out_fail;
if (ftrace_init_buffers(ti->buffers, ti->trace_buffer,
ti->pages) < 0)
goto out_fail;
if (!ti->max_tr_ring_buffer)
return 0;
ti->max_tr_buffers = calloc(sizeof(*ti->max_tr_buffers), nr_cpu_ids);
if (ti->max_tr_buffers == NULL)
goto out_fail;
if (ftrace_init_buffers(ti->max_tr_buffers, ti->max_tr_ring_buffer,
ti->max_tr_pages) < 0)
goto out_fail;
return 0;
out_fail:
free(ti->max_tr_buffers);
free(ti->buffers);
return -1;
}
static void ftrace_destroy_all_instance_buffers()
{
int i;
for (i = 0; i < instance_count; i++)
{
struct trace_instance *ti = &trace_instances[i];
if (ti->max_tr_ring_buffer) {
ftrace_destroy_buffers(ti->max_tr_buffers);
free(ti->max_tr_buffers);
}
ftrace_destroy_buffers(ti->buffers);
free(ti->buffers);
}
}
static void ftrace_destroy_instances()
{
ftrace_destroy_all_instance_buffers();
free(trace_instances);
}
static int ftrace_init_instances()
{
int i;
struct trace_instance *ti;
struct list_data list_data;
struct list_data *ld = &list_data;
if (!multiple_instances_available)
return 0;
BZERO(ld, sizeof(struct list_data));
ld->start = ftrace_trace_arrays;
ld->end = global_trace;
ld->flags = LIST_ALLOCATE;
instance_count = do_list(ld);
/* The do_list count includes the list_head, which is not a
* proper instance */
instance_count--;
if (instance_count <= 0)
return 0;
trace_instances = calloc(sizeof(struct trace_instance), instance_count);
/* We start i at 1 to skip over the list_head and continue to the last
* instance, which lies at index instance_count */
for (i = 1; i <= instance_count; i++)
{
ulong instance_ptr;
ulong name_addr;
int ret;
ti = &trace_instances[i-1];
instance_ptr = ld->list_ptr[i];
read_value(name_addr, instance_ptr, trace_array, name);
if (!name_addr)
{
console("Instance name is NULL\n");
}
else if (!read_string(name_addr, ti->name, sizeof(ti->name)))
{
console("Failed to read instance name at address %p\n", (void*)name_addr);
goto out_fail;
}
ret = ftrace_init_trace(ti, instance_ptr);
if (ret < 0)
goto out_fail;
}
FREEBUF(ld->list_ptr);
return 0;
out_fail:
/* We've already freed the current instance's trace buffer info, so
* we'll clear that out to avoid double freeing in
* ftrace_destroy_instances() */
BZERO(ti, sizeof(struct trace_instance));
ftrace_destroy_instances();
return -1;
}
static int ftrace_init_current_tracer(void)
{
ulong addr;
char tmp[128];
/* Get current tracer name */
if (encapsulated_current_trace) {
read_value(addr, global_trace, trace_array, current_trace);
} else {
read_value(addr, current_trace, POINTER_SYM, POINTER);
}
read_value(addr, addr, tracer, name);
read_string(addr, tmp, 128);
current_tracer_name = strdup(tmp);
if (current_tracer_name == NULL)
goto out_fail;
return 0;
out_fail:
return -1;
}
static int ftrace_init(void)
{
struct syment *sym_global_trace;
struct syment *sym_max_tr_trace;
struct syment *sym_ftrace_events;
struct syment *sym_current_trace;
struct syment *sym_ftrace_trace_arrays;
sym_global_trace = symbol_search("global_trace");
sym_ftrace_events = symbol_search("ftrace_events");
sym_ftrace_trace_arrays = symbol_search("ftrace_trace_arrays");
if (sym_global_trace == NULL || sym_ftrace_events == NULL)
return -1;
global_trace = sym_global_trace->value;
ftrace_events = sym_ftrace_events->value;
if (sym_ftrace_trace_arrays)
{
multiple_instances_available = 1;
ftrace_trace_arrays = sym_ftrace_trace_arrays->value;
}
if (MEMBER_EXISTS("buffer_page", "real_end"))
buffer_page_real_end_available = 1;
if (MEMBER_EXISTS("trace_array", "current_trace")) {
encapsulated_current_trace = 1;
} else {
sym_current_trace = symbol_search("current_trace");
if (sym_current_trace == NULL)
return -1;
current_trace = sym_current_trace->value;
}
if (MEMBER_EXISTS("trace_array", "array_buffer") ||
MEMBER_EXISTS("trace_array", "trace_buffer")) {
array_buffer_available = 1;
if (MEMBER_EXISTS("trace_array", "max_buffer"))
max_buffer_available = 1;
} else {
sym_max_tr_trace = symbol_search("max_tr");
if (sym_max_tr_trace == NULL)
return -1;
max_tr_trace = sym_max_tr_trace->value;
}
if (!try_get_symbol_data("nr_cpu_ids", sizeof(int), &nr_cpu_ids))
nr_cpu_ids = 1;
if (init_offsets() < 0)
return -1;
print_offsets();
if (ftrace_init_trace(&global_trace_instance, global_trace) < 0)
goto out_0;
if (ftrace_init_instances() < 0)
goto out_1;
if (ftrace_init_event_types() < 0)
goto out_2;
if (ftrace_init_current_tracer() < 0)
goto out_3;
return 0;
out_3:
ftrace_destroy_event_types();
out_2:
ftrace_destroy_instances();
out_1:
if (global_trace_instance.max_tr_ring_buffer) {
ftrace_destroy_buffers(global_trace_instance.max_tr_buffers);
free(global_trace_instance.max_tr_buffers);
}
ftrace_destroy_buffers(global_trace_instance.buffers);
free(global_trace_instance.buffers);
out_0:
return -1;
}
static void ftrace_destroy(void)
{
free(current_tracer_name);
ftrace_destroy_event_types();
ftrace_destroy_instances();
if (global_trace_instance.max_tr_ring_buffer) {
ftrace_destroy_buffers(global_trace_instance.max_tr_buffers);
free(global_trace_instance.max_tr_buffers);
}
ftrace_destroy_buffers(global_trace_instance.buffers);
free(global_trace_instance.buffers);
}
static int ftrace_dump_page(int fd, ulong page, void *page_tmp)
{
ulong raw_page;
read_value(raw_page, page, buffer_page, page);
if (!readmem(raw_page, KVADDR, page_tmp, PAGESIZE(), "get page context",
RETURN_ON_ERROR))
goto out_fail;
if (write_and_check(fd, page_tmp, PAGESIZE()))
return -1;
return 0;
out_fail:
return -1;
}
static
void ftrace_dump_buffer(int fd, struct ring_buffer_per_cpu *cpu_buffer,
unsigned pages, void *page_tmp)
{
int i;
for (i = 0; i < cpu_buffer->nr_linear_pages; i++) {
if (ftrace_dump_page(fd, cpu_buffer->linear_pages[i],
page_tmp) < 0)
break;
}
}
static int try_mkdir(const char *pathname, mode_t mode)
{
int ret;
ret = mkdir(pathname, mode);
if (ret < 0) {
if (errno == EEXIST)
return 0;
error(INFO, "mkdir failed\n");
return -1;
}
return 0;
}
static int ftrace_dump_buffers(const char *per_cpu_path,
struct trace_instance *ti)
{
int i;
void *page_tmp;
char path[PATH_MAX];
int fd;
page_tmp = malloc(PAGESIZE());
if (page_tmp == NULL)
return -1;
for (i = 0; i < nr_cpu_ids; i++) {
struct ring_buffer_per_cpu *cpu_buffer = &ti->buffers[i];
if (!cpu_buffer->kaddr)
continue;
snprintf(path, sizeof(path), "%s/cpu%d", per_cpu_path, i);
if (try_mkdir(path, 0755) < 0)
goto out_fail;
snprintf(path, sizeof(path), "%s/cpu%d/trace_pipe_raw",
per_cpu_path, i);
fd = open(path, O_WRONLY | O_CREAT, 0644);
if (fd < 0)
goto out_fail;
ftrace_dump_buffer(fd, cpu_buffer, ti->pages, page_tmp);
close(fd);
}
free(page_tmp);
return 0;
out_fail:
free(page_tmp);
return -1;
}
#define MAX_CACHE_ID 256
struct ftrace_field {
const char *name;
const char *type;
int offset;
int size;
int is_signed;
};
struct event_type {
struct event_type *next;
const char *system;
const char *name;
int plugin;
const char *print_fmt;
int id;
int nfields;
struct ftrace_field *fields;
};
static struct event_type *event_type_cache[MAX_CACHE_ID];
static struct event_type **event_types;
static int nr_event_types;
static struct ftrace_field *ftrace_common_fields;
static int ftrace_common_fields_count;
static int syscall_get_enter_fields(ulong call, ulong *fields)
{
static int inited;
static int data_offset;
static int enter_fields_offset;
ulong metadata;
if (inited)
goto work;
inited = 1;
data_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "data"),
MEMBER_OFFSET("trace_event_call", "data"));
if (data_offset < 0) {
/*
* rhel-7.6 moved the .data member into an anonymous union.
*/
if (MEMBER_EXISTS("ftrace_event_call", "rh_data") &&
MEMBER_EXISTS("ftrace_event_data", "data")) {
data_offset = MEMBER_OFFSET("ftrace_event_call", "rh_data") +
MEMBER_OFFSET("ftrace_event_data", "data");
inited = 2;
} else
return -1;
}
enter_fields_offset = MEMBER_OFFSET("syscall_metadata", "enter_fields");
if (enter_fields_offset < 0)
return -1;
work:
if (data_offset < 0 || enter_fields_offset < 0)
return -1;
if (!readmem(call + data_offset, KVADDR, &metadata, sizeof(metadata),
"read ftrace_event_call data", RETURN_ON_ERROR))
return -1;
if (inited == 2) {
if (!readmem(metadata, KVADDR, &metadata, sizeof(metadata),
"read ftrace_event_call data (indirect rh_data)", RETURN_ON_ERROR))
return -1;
}
*fields = metadata + enter_fields_offset;
return 0;
}
static int syscall_get_exit_fields_old(ulong call, ulong *fields)
{
static int inited;
static int data_offset;
static int exit_fields_offset;
ulong metadata;
if (inited)
goto work;
inited = 1;
data_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "data"),
MEMBER_OFFSET("trace_event_call", "data"));
if (data_offset < 0)
return -1;
exit_fields_offset = MEMBER_OFFSET("syscall_metadata", "exit_fields");
if (exit_fields_offset < 0)
return -1;
work:
if (data_offset < 0 || exit_fields_offset < 0)
return -1;
if (!readmem(call + data_offset, KVADDR, &metadata, sizeof(metadata),
"read ftrace_event_call data", RETURN_ON_ERROR))
return -1;
*fields = metadata + exit_fields_offset;
return 0;
}
static int syscall_get_exit_fields(ulong call, ulong *fields)
{
static int inited;
static ulong syscall_exit_fields_value;
if (!inited) {
struct syment *sp;
if (!(sp = symbol_search("syscall_exit_fields"))) {
inited = -1;
} else {
syscall_exit_fields_value = sp->value;
inited = 1;
}
}
if (inited == -1)
return syscall_get_exit_fields_old(call, fields);
*fields = syscall_exit_fields_value;
return 0;
}
static
int ftrace_get_event_type_fields(ulong call, ulong *fields)
{
static int inited;
static int fields_offset;
static int class_offset;
static int get_fields_offset;
static ulong syscall_get_enter_fields_value;
static ulong syscall_get_exit_fields_value;
struct syment *sp;
ulong class, get_fields;
if (inited)
goto work;
inited = 1;
fields_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "fields"),
MEMBER_OFFSET("trace_event_call", "fields"));
class_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "class"),
MEMBER_OFFSET("trace_event_call", "class"));
if (class_offset < 0)
goto work;
inited = 2;
fields_offset = MAX(MEMBER_OFFSET("ftrace_event_class", "fields"),
MEMBER_OFFSET("trace_event_class", "fields"));
if (fields_offset < 0)
return -1;
get_fields_offset = MAX(MEMBER_OFFSET("ftrace_event_class", "get_fields"),
MEMBER_OFFSET("trace_event_class", "get_fields"));
if ((sp = symbol_search("syscall_get_enter_fields")) != NULL)
syscall_get_enter_fields_value = sp->value;
if ((sp = symbol_search("syscall_get_exit_fields")) != NULL)
syscall_get_exit_fields_value = sp->value;
work:
if (fields_offset < 0)
return -1;
if (inited == 1) {
*fields = call + fields_offset;
return 0;
}
if (!readmem(call + class_offset, KVADDR, &class, sizeof(class),
"read ftrace_event_call class", RETURN_ON_ERROR))
return -1;
if (!readmem(class + get_fields_offset, KVADDR, &get_fields,
sizeof(get_fields), "read ftrace_event_call get_fields",
RETURN_ON_ERROR))
return -1;
if (!get_fields) {
*fields = class + fields_offset;
return 0;
}
if (get_fields == syscall_get_enter_fields_value)
return syscall_get_enter_fields(call, fields);
if (get_fields == syscall_get_exit_fields_value)
return syscall_get_exit_fields(call, fields);
fprintf(fp, "Unkown get_fields function\n");
return -1;
}
static int ftrace_init_event_fields(ulong fields_head, int *pnfields,
struct ftrace_field **pfields)
{
ulong pos;
int nfields = 0, max_fields = 16;
struct ftrace_field *fields = NULL;
read_value(pos, fields_head, list_head, next);
if (pos == 0) {
if (verbose)
fprintf(fp, "no field, head: %lu\n", fields_head);
return 0;
}
fields = malloc(sizeof(*fields) * max_fields);
if (fields == NULL)
return -1;
while (pos != fields_head) {
ulong field;
ulong name_addr, type_addr;
char field_name[128], field_type[128];
int offset, size, is_signed;
field = pos - koffset(ftrace_event_field, link);
/* Read a field from the core */
read_value(name_addr, field, ftrace_event_field, name);
read_value(type_addr, field, ftrace_event_field, type);
read_value(offset, field, ftrace_event_field, offset);
read_value(size, field, ftrace_event_field, size);
read_value(is_signed, field, ftrace_event_field, is_signed);
if (!read_string(name_addr, field_name, 128))
goto out_fail;
if (!read_string(type_addr, field_type, 128))
goto out_fail;
/* Enlarge fields array when need */
if (nfields >= max_fields) {
void *tmp;
max_fields = nfields * 2;
tmp = realloc(fields, sizeof(*fields) * max_fields);
if (tmp == NULL)
goto out_fail;
fields = tmp;
}
/* Set up and Add a field */
fields[nfields].offset = offset;
fields[nfields].size = size;
fields[nfields].is_signed = is_signed;
fields[nfields].name = strdup(field_name);
if (fields[nfields].name == NULL)
goto out_fail;
fields[nfields].type = strdup(field_type);
if (fields[nfields].type == NULL) {
free(fields[nfields].name);
goto out_fail;
}
nfields++;
/* Advance to the next field */
read_value(pos, pos, list_head, next);
}
*pnfields = nfields;
*pfields = fields;
return 0;
out_fail:
for (nfields--; nfields >= 0; nfields--) {
free(fields[nfields].name);
free(fields[nfields].type);
}
free(fields);
return -1;
}
static int ftrace_init_event_type(ulong call, struct event_type *aevent_type)
{
ulong fields_head = 0;
if (ftrace_get_event_type_fields(call, &fields_head) < 0)
return -1;
return ftrace_init_event_fields(fields_head, &aevent_type->nfields,
&aevent_type->fields);
}
static int ftrace_init_common_fields(void)
{
ulong ftrace_common_fields_head;
struct syment *sp;
sp = symbol_search("ftrace_common_fields");
if (!sp)
return 0;
ftrace_common_fields_head = sp->value;
return ftrace_init_event_fields(ftrace_common_fields_head,
&ftrace_common_fields_count, &ftrace_common_fields);
}
static void ftrace_destroy_event_types(void)
{
int i, j;
for (i = 0; i < nr_event_types; i++) {
for (j = 0; j < event_types[i]->nfields; j++) {
free(event_types[i]->fields[j].name);
free(event_types[i]->fields[j].type);
}
free(event_types[i]->fields);
free(event_types[i]->system);
free(event_types[i]->name);
free(event_types[i]->print_fmt);
free(event_types[i]);
}
free(event_types);
free(ftrace_common_fields);
}
static
int ftrace_get_event_type_name(ulong call, char *name, int len)
{
static int inited;
static int name_offset;
static int flags_offset;
static int tp_name_offset;
static long tracepoint_flag;
uint flags;
ulong name_addr;
if (inited)
goto work;
name_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "tp"),
MEMBER_OFFSET("trace_event_call", "tp"));
if (name_offset >= 0) {
flags_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "flags"),
MEMBER_OFFSET("trace_event_call", "flags"));
if (flags_offset < 0)
return -1;
tp_name_offset = MEMBER_OFFSET("tracepoint", "name");
if (tp_name_offset < 0)
return -1;
if (!enumerator_value("TRACE_EVENT_FL_TRACEPOINT", &tracepoint_flag))
return -1;
inited = 2;
} else {
name_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "name"),
MEMBER_OFFSET("trace_event_call", "name"));
inited = 1;
}
work:
if (name_offset < 0)
return -1;
if (!readmem(call + name_offset, KVADDR, &name_addr, sizeof(name_addr),
"read ftrace_event_call name_addr", RETURN_ON_ERROR))
return -1;
if (inited == 2) {
if (!readmem(call + flags_offset, KVADDR, &flags,
sizeof(flags), "read ftrace_event_call flags",
RETURN_ON_ERROR))
return -1;
if (flags & (uint)tracepoint_flag) {
if (!readmem(name_addr + tp_name_offset, KVADDR,
&name_addr, sizeof(name_addr),
"read tracepoint name", RETURN_ON_ERROR))
return -1;
}
}
if (!read_string(name_addr, name, len))
return -1;
return 0;
}
static
int ftrace_get_event_type_system(ulong call, char *system, int len)
{
static int inited;
static int sys_offset;
static int class_offset;
ulong ptr = call;
ulong sys_addr;
if (inited)
goto work;
inited = 1;
sys_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "system"),
MEMBER_OFFSET("trace_event_call", "system"));
if (sys_offset >= 0)
goto work;
class_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "class"),
MEMBER_OFFSET("trace_event_call", "class"));
if (class_offset < 0)
return -1;
sys_offset = MAX(MEMBER_OFFSET("ftrace_event_class", "system"),
MEMBER_OFFSET("trace_event_class", "system"));
inited = 2;
work:
if (sys_offset < 0)
return -1;
if (inited == 2 && !readmem(call + class_offset, KVADDR, &ptr,
sizeof(ptr), "read ftrace_event_call class_addr",
RETURN_ON_ERROR))
return -1;
if (!readmem(ptr + sys_offset, KVADDR, &sys_addr, sizeof(sys_addr),
"read ftrace_event_call sys_addr", RETURN_ON_ERROR))
return -1;
if (!read_string(sys_addr, system, len))
return -1;
return 0;
}
static int read_long_string(ulong kvaddr, char **buf)
{
char strbuf[MIN_PAGE_SIZE], *ret_buf = NULL;
ulong kp;
int cnt1, cnt2, size;
again:
kp = kvaddr;
size = 0;
for (;;) {
cnt1 = MIN_PAGE_SIZE - (kp & (MIN_PAGE_SIZE-1));
if (!readmem(kp, KVADDR, strbuf, cnt1,
"readstring characters", QUIET|RETURN_ON_ERROR))
return -1;
cnt2 = strnlen(strbuf, cnt1);
if (ret_buf)
memcpy(ret_buf + size, strbuf, cnt2);
kp += cnt2;
size += cnt2;
if (cnt2 < cnt1) {
if (ret_buf) {
break;
} else {
ret_buf = malloc(size + 1);
if (!ret_buf)
return -1;
goto again;
}
}
}
ret_buf[size] = '\0';
*buf = ret_buf;
return size;
}
static
int ftrace_get_event_type_print_fmt(ulong call, char **print_fmt)
{
static int inited;
static int fmt_offset;
ulong fmt_addr;
if (!inited) {
inited = 1;
fmt_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "print_fmt"),
MEMBER_OFFSET("trace_event_call", "print_fmt"));
}
if (fmt_offset < 0) {
*print_fmt = strdup("Unknown print_fmt");
return 0;
}
if (!readmem(call + fmt_offset, KVADDR, &fmt_addr, sizeof(fmt_addr),
"read ftrace_event_call fmt_addr", RETURN_ON_ERROR))
return -1;
return read_long_string(fmt_addr, print_fmt);
}
static
int ftrace_get_event_type_id(ulong call, int *id)
{
static int inited;
static int id_offset;
if (!inited) {
inited = 1;
id_offset = MAX(MEMBER_OFFSET("ftrace_event_call", "id"),
MEMBER_OFFSET("trace_event_call", "id"));
if (id_offset < 0) {
/* id = call->event.type */
int f1 = MAX(MEMBER_OFFSET("ftrace_event_call", "event"),
MEMBER_OFFSET("trace_event_call", "event"));
int f2 = MEMBER_OFFSET("trace_event", "type");
if (f1 >= 0 && f2 >= 0)
id_offset = f1 + f2;
}
}
if (id_offset < 0)
return -1;
if (!readmem(call + id_offset, KVADDR, id, sizeof(*id),
"read ftrace_event_call id", RETURN_ON_ERROR))
return -1;
return 0;
}
static int ftrace_init_event_types(void)
{
ulong event;
struct event_type *aevent_type;
int max_types = 128;
event_types = malloc(sizeof(*event_types) * max_types);
if (event_types == NULL)
return -1;
read_value(event, ftrace_events, list_head, next);
while (event != ftrace_events) {
ulong call;
char name[128], system[128], *print_fmt;
int id;
call = event - koffset(ftrace_event_call, list);
/* Read a event type from the core */
if (ftrace_get_event_type_id(call, &id) < 0 ||
ftrace_get_event_type_name(call, name, 128) < 0 ||
ftrace_get_event_type_system(call, system, 128) < 0 ||
ftrace_get_event_type_print_fmt(call, &print_fmt) < 0)
goto out_fail;
/* Enlarge event types array when need */
if (nr_event_types >= max_types) {
void *tmp;
max_types = 2 * nr_event_types;
tmp = realloc(event_types,
sizeof(*event_types) * max_types);
if (tmp == NULL) {
free(print_fmt);
goto out_fail;
}
event_types = tmp;
}
/* Create a event type */
aevent_type = malloc(sizeof(*aevent_type));
if (aevent_type == NULL) {
free(print_fmt);
goto out_fail;
}
aevent_type->system = strdup(system);
aevent_type->name = strdup(name);
aevent_type->print_fmt = print_fmt;
aevent_type->id = id;
aevent_type->nfields = 0;
aevent_type->fields = NULL;
if (aevent_type->system == NULL || aevent_type->name == NULL)
goto out_fail_free_aevent_type;
if (ftrace_init_event_type(call, aevent_type) < 0)
goto out_fail_free_aevent_type;
if (!strcmp("ftrace", aevent_type->system))
aevent_type->plugin = 1;
else
aevent_type->plugin = 0;
/* Add a event type */
event_types[nr_event_types++] = aevent_type;
if ((unsigned)id < MAX_CACHE_ID)
event_type_cache[id] = aevent_type;
/* Advance to the next event type */
read_value(event, event, list_head, next);
}
if (ftrace_init_common_fields() < 0)
goto out_fail;
return 0;
out_fail_free_aevent_type:
free(aevent_type->system);
free(aevent_type->name);
free(aevent_type->print_fmt);
free(aevent_type);
out_fail:
ftrace_destroy_event_types();
return -1;
}
#define default_common_field_count 5
static int ftrace_dump_event_type(struct event_type *t, const char *path)
{
char format_path[PATH_MAX];
FILE *out;
int i, nfields;
struct ftrace_field *fields;
int printed_common_field = 0;
snprintf(format_path, sizeof(format_path), "%s/format", path);
out = fopen(format_path, "w");
if (out == NULL)
return -1;
fprintf(out, "name: %s\n", t->name);
fprintf(out, "ID: %d\n", t->id);
fprintf(out, "format:\n");
if (ftrace_common_fields_count) {
nfields = ftrace_common_fields_count;
fields = ftrace_common_fields;
} else {
nfields = default_common_field_count;
fields = &t->fields[t->nfields - nfields];
}
again:
for (i = nfields - 1; i >= 0; i--) {
/*
* Smartly shows the array type(except dynamic array).
* Normal:
* field:TYPE VAR
* If TYPE := TYPE[LEN], it is shown:
* field:TYPE VAR[LEN]
*/
struct ftrace_field *field = &fields[i];
const char *array_descriptor = strchr(field->type, '[');
if (!strncmp(field->type, "__data_loc", 10))
array_descriptor = NULL;
if (!array_descriptor) {
fprintf(out, "\tfield:%s %s;\toffset:%u;"
"\tsize:%u;\tsigned:%d;\n",
field->type, field->name, field->offset,
field->size, !!field->is_signed);
} else {
fprintf(out, "\tfield:%.*s %s%s;\toffset:%u;"
"\tsize:%u;\tsigned:%d;\n",
(int)(array_descriptor - field->type),
field->type, field->name,
array_descriptor, field->offset,
field->size, !!field->is_signed);
}
}
if (!printed_common_field) {
fprintf(out, "\n");
if (ftrace_common_fields_count)
nfields = t->nfields;
else
nfields = t->nfields - default_common_field_count;
fields = t->fields;
printed_common_field = 1;
goto again;
}
fprintf(out, "\nprint fmt: %s\n", t->print_fmt);
fclose(out);
return 0;
}
static int ftrace_dump_event_types(const char *events_path)
{
int i;
for (i = 0; i < nr_event_types; i++) {
char path[PATH_MAX];
struct event_type *t = event_types[i];
snprintf(path, sizeof(path), "%s/%s", events_path, t->system);
if (try_mkdir(path, 0755) < 0)
return -1;
snprintf(path, sizeof(path), "%s/%s/%s", events_path,
t->system, t->name);
if (try_mkdir(path, 0755) < 0)
return -1;
if (ftrace_dump_event_type(t, path) < 0)
return -1;
}
return 0;
}
static void show_basic_info(void)
{
fprintf(fp, "current tracer is %s\n", current_tracer_name);
}
static int dump_saved_cmdlines(const char *dump_tracing_dir)
{
char path[PATH_MAX];
FILE *out;
int i;
struct task_context *tc;
snprintf(path, sizeof(path), "%s/saved_cmdlines", dump_tracing_dir);
out = fopen(path, "w");
if (out == NULL)
return -1;
tc = FIRST_CONTEXT();
for (i = 0; i < RUNNING_TASKS(); i++)
fprintf(out, "%d %s\n", (int)tc[i].pid, tc[i].comm);
fclose(out);
return 0;
}
static int dump_kallsyms(const char *dump_tracing_dir)
{
char path[PATH_MAX];
FILE *out;
int i;
struct syment *sp;
snprintf(path, sizeof(path), "%s/kallsyms", dump_tracing_dir);
out = fopen(path, "w");
if (out == NULL)
return -1;
for (sp = st->symtable; sp < st->symend; sp++)
fprintf(out, "%lx %c %s\n", sp->value, sp->type, sp->name);
for (i = 0; i < st->mods_installed; i++) {
struct load_module *lm = &st->load_modules[i];
for (sp = lm->mod_symtable; sp <= lm->mod_symend; sp++) {
if (!strncmp(sp->name, "_MODULE_", strlen("_MODULE_")))
continue;
fprintf(out, "%lx %c %s\t[%s]\n", sp->value, sp->type,
sp->name, lm->mod_name);
}
}
fclose(out);
return 0;
}
static int trace_cmd_data_output(int fd);
#define FTRACE_DUMP_SYMBOLS (1 << 0)
#define FTRACE_DUMP_META_DATA (1 << 1)
static int populate_ftrace_dir_tree(struct trace_instance *ti,
char *root, uint flags)
{
char path[PATH_MAX];
int ret;
ret = mkdir(root, 0755);
if (ret < 0) {
if (errno == EEXIST)
error(INFO, "mkdir: %s exists\n", root);
return FALSE;
}
snprintf(path, sizeof(path), "%s/per_cpu", root);
if (try_mkdir(path, 0755) < 0)
return FALSE;
if (ftrace_dump_buffers(path, ti) < 0)
return FALSE;
if (flags & FTRACE_DUMP_META_DATA) {
/* Dump event types */
snprintf(path, sizeof(path), "%s/events", root);
if (try_mkdir(path, 0755) < 0)
return FALSE;
if (ftrace_dump_event_types(path) < 0)
return FALSE;
/* Dump pids with corresponding cmdlines */
if (dump_saved_cmdlines(root) < 0)
return FALSE;
}
if (flags & FTRACE_DUMP_SYMBOLS) {
/* Dump all symbols of the kernel */
dump_kallsyms(root);
}
return TRUE;
}
static void ftrace_dump(int argc, char *argv[])
{
int c;
int i;
uint flags = 0;
char *dump_tracing_dir;
char instance_path[PATH_MAX];
while ((c = getopt(argc, argv, "smt")) != EOF) {
switch(c)
{
case 's':
flags |= FTRACE_DUMP_SYMBOLS;
break;
case 'm':
flags |= FTRACE_DUMP_META_DATA;
break;
case 't':
if (flags & FTRACE_DUMP_SYMBOLS ||
flags & FTRACE_DUMP_META_DATA ||
argc - optind > 1)
cmd_usage(pc->curcmd, SYNOPSIS);
else {
char *trace_dat = "trace.dat";
int fd;
if (argc - optind == 0)
trace_dat = "trace.dat";
else if (argc - optind == 1)
trace_dat = argv[optind];
fd = open(trace_dat, O_WRONLY | O_CREAT
| O_TRUNC, 0644);
trace_cmd_data_output(fd);
close(fd);
}
return;
default:
cmd_usage(pc->curcmd, SYNOPSIS);
return;
}
}
if (argc - optind == 0) {
dump_tracing_dir = "dump_tracing_dir";
} else if (argc - optind == 1) {
dump_tracing_dir = argv[optind];
} else {
cmd_usage(pc->curcmd, SYNOPSIS);
return;
}
if (!populate_ftrace_dir_tree(&global_trace_instance, dump_tracing_dir, flags))
return;
if (!multiple_instances_available || instance_count == 0)
return;
/* Create an instances directory, and dump instance data in there */
snprintf(instance_path, sizeof(instance_path),
"%s/instances", dump_tracing_dir);
if (try_mkdir(instance_path, 0755) < 0)
return;
/* Don't care about the flags anymore */
flags = 0;
for (i = 0; i < instance_count; i++)
{
struct trace_instance *ti = &trace_instances[i];
snprintf(instance_path, sizeof(instance_path),
"%s/instances/%s", dump_tracing_dir,
ti->name);
if (populate_ftrace_dir_tree(ti, instance_path, flags) < 0)
break;
}
return;
}
static void ftrace_show(int argc, char *argv[])
{
char buf[4096];
char tmp[] = "/tmp/crash.trace_dat.XXXXXX";
char *trace_cmd = "trace-cmd", *env_trace_cmd = getenv("TRACE_CMD");
int fd;
FILE *file;
size_t ret;
size_t nitems __attribute__ ((__unused__));
/* check trace-cmd */
if (env_trace_cmd)
trace_cmd = env_trace_cmd;
buf[0] = 0;
if ((file = popen(trace_cmd, "r"))) {
ret = fread(buf, 1, sizeof(buf), file);
buf[ret] = 0;
pclose(file);
}
if (!strstr(buf, "trace-cmd version")) {
if (env_trace_cmd)
fprintf(fp, "Invalid environment TRACE_CMD: %s\n",
env_trace_cmd);
else
fprintf(fp, "\"trace show\" requires trace-cmd.\n"
"please set the environment TRACE_CMD "
"if you installed it in a special path\n"
);
return;
}
/* dump trace.dat to the temp file */
fd = mkstemp(tmp);
if (fd < 0)
return;
if (trace_cmd_data_output(fd) < 0)
goto out;
/* splice the output of trace-cmd to user */
snprintf(buf, sizeof(buf), "%s report %s", trace_cmd, tmp);
if (!(file = popen(buf, "r")))
goto out;
for (;;) {
ret = fread(buf, 1, sizeof(buf), file);
if (ret == 0)
break;
nitems = fwrite(buf, 1, ret, fp);
}
pclose(file);
out:
close(fd);
unlink(tmp);
return;
}
static void cmd_ftrace(void)
{
if (argcnt == 1)
show_basic_info();
else if (!strcmp(args[1], "dump"))
ftrace_dump(argcnt - 1, args + 1);
else if (!strcmp(args[1], "show"))
ftrace_show(argcnt - 1, args + 1);
else if (!strcmp(args[1], "report"))
ftrace_show(argcnt - 1, args + 1);
else
cmd_usage(pc->curcmd, SYNOPSIS);
}
static char *help_ftrace[] = {
"trace",
"show or dump the tracing info",
"[ <show [-c <cpulist>] [-f [no]<flagname>]> | <dump [-sm] <dest-dir>> ] | <dump -t <trace.dat> ]",
"trace",
" shows the current tracer and other informations.",
"",
"trace show",
" shows all events with readability text(sorted by timestamp)",
"",
"trace report",
" the same as \"trace show\"",
"",
"trace dump [-sm] <dest-dir>",
" dump ring_buffers to dest-dir. Then you can parse it",
" by other tracing tools. The dirs and files are generated",
" the same as debugfs/tracing.",
" -m: also dump metadata of ftrace.",
" -s: also dump symbols of the kernel.",
"trace dump -t [output-file-name]",
" dump ring_buffers and all meta data to a file that can",
" be parsed by trace-cmd. Default output file name is \"trace.dat\".",
NULL
};
static struct command_table_entry command_table[] = {
{ "trace", cmd_ftrace, help_ftrace, 0 },
{ NULL, 0, 0, 0 }
};
static int ftrace_initialized;
void __attribute__((constructor))
trace_init(void)
{
if (ftrace_init() < 0)
return;
ftrace_initialized = 1;
register_extension(command_table);
}
void __attribute__((destructor))
trace_fini(void)
{
if (ftrace_initialized)
ftrace_destroy();
}
#define TRACE_CMD_FILE_VERSION_STRING "6"
static inline int host_bigendian(void)
{
unsigned char str[] = { 0x1, 0x2, 0x3, 0x4 };
unsigned int *ptr;
ptr = (unsigned int *)str;
return *ptr == 0x01020304;
}
static char *tmp_file_buf;
static unsigned long long tmp_file_pos;
static unsigned long long tmp_file_size;
static int tmp_file_error;
static int init_tmp_file(void)
{
tmp_file_buf = malloc(4096);
if (tmp_file_buf == NULL)
return -1;
tmp_file_pos = 0;
tmp_file_size = 4096;
tmp_file_error = 0;
return 0;
}
static void destory_tmp_file(void)
{
free(tmp_file_buf);
}
#define tmp_fprintf(fmt...) \
do { \
char *__buf = tmp_file_buf; \
unsigned long long __pos; \
\
if (tmp_file_error) \
break; \
__pos = tmp_file_pos; \
__pos += snprintf(__buf + __pos, tmp_file_size - __pos, fmt); \
if (__pos >= tmp_file_size) { \
tmp_file_size = __pos + tmp_file_size; \
__buf = realloc(__buf, tmp_file_size); \
if (!__buf) { \
tmp_file_error = 1; \
break; \
} \
tmp_file_buf = __buf; \
__pos = tmp_file_pos; \
__pos += snprintf(__buf + __pos, tmp_file_size - __pos, fmt);\
} \
tmp_file_pos = __pos; \
} while (0)
static int tmp_file_record_size4(int fd)
{
unsigned int size = tmp_file_pos;
if (tmp_file_error)
return -1;
if (write_and_check(fd, &size, 4))
return -1;
return 0;
}
static int tmp_file_record_size8(int fd)
{
if (tmp_file_error)
return -1;
if (write_and_check(fd, &tmp_file_pos, 8))
return -1;
return 0;
}
static int tmp_file_flush(int fd)
{
if (tmp_file_error)
return -1;
if (write_and_check(fd, tmp_file_buf, tmp_file_pos))
return -1;
tmp_file_pos = 0;
return 0;
}
static int save_initial_data(int fd)
{
int page_size;
char buf[20];
if (write_and_check(fd, "\027\010\104tracing", 10))
return -1;
if (write_and_check(fd, TRACE_CMD_FILE_VERSION_STRING,
strlen(TRACE_CMD_FILE_VERSION_STRING) + 1))
return -1;
/* Crash ensure core file endian and the host endian are the same */
if (host_bigendian())
buf[0] = 1;
else
buf[0] = 0;
if (write_and_check(fd, buf, 1))
return -1;
/* save size of long (this may not be what the kernel is) */
buf[0] = sizeof(long);
if (write_and_check(fd, buf, 1))
return -1;
page_size = PAGESIZE();
if (write_and_check(fd, &page_size, 4))
return -1;
return 0;
}
static int save_header_files(int fd)
{
/* save header_page */
if (write_and_check(fd, "header_page", 12))
return -1;
tmp_fprintf("\tfield: u64 timestamp;\toffset:0;\tsize:8;\tsigned:0;\n");
tmp_fprintf("\tfield: local_t commit;\toffset:8;\tsize:%u;\t"
"signed:1;\n", (unsigned int)sizeof(long));
tmp_fprintf("\tfield: int overwrite;\toffset:8;\tsize:%u;\tsigned:1;\n",
(unsigned int)sizeof(long));
tmp_fprintf("\tfield: char data;\toffset:%u;\tsize:%u;\tsigned:1;\n",
(unsigned int)(8 + sizeof(long)),
(unsigned int)(PAGESIZE() - 8 - sizeof(long)));
if (tmp_file_record_size8(fd))
return -1;
if (tmp_file_flush(fd))
return -1;
/* save header_event */
if (write_and_check(fd, "header_event", 13))
return -1;
tmp_fprintf(
"# compressed entry header\n"
"\ttype_len : 5 bits\n"
"\ttime_delta : 27 bits\n"
"\tarray : 32 bits\n"
"\n"
"\tpadding : type == 29\n"
"\ttime_extend : type == 30\n"
"\tdata max type_len == 28\n"
);
if (tmp_file_record_size8(fd))
return -1;
if (tmp_file_flush(fd))
return -1;
return 0;
}
static int save_event_file(int fd, struct event_type *t)
{
int i, nfields;
struct ftrace_field *fields;
int printed_common_field = 0;
tmp_fprintf("name: %s\n", t->name);
tmp_fprintf("ID: %d\n", t->id);
tmp_fprintf("format:\n");
if (ftrace_common_fields_count) {
nfields = ftrace_common_fields_count;
fields = ftrace_common_fields;
} else {
nfields = default_common_field_count;
fields = &t->fields[t->nfields - nfields];
}
again:
for (i = nfields - 1; i >= 0; i--) {
/*
* Smartly shows the array type(except dynamic array).
* Normal:
* field:TYPE VAR
* If TYPE := TYPE[LEN], it is shown:
* field:TYPE VAR[LEN]
*/
struct ftrace_field *field = &fields[i];
const char *array_descriptor = strchr(field->type, '[');
if (!strncmp(field->type, "__data_loc", 10))
array_descriptor = NULL;
if (!array_descriptor) {
tmp_fprintf("\tfield:%s %s;\toffset:%u;"
"\tsize:%u;\tsigned:%d;\n",
field->type, field->name, field->offset,
field->size, !!field->is_signed);
} else {
tmp_fprintf("\tfield:%.*s %s%s;\toffset:%u;"
"\tsize:%u;\tsigned:%d;\n",
(int)(array_descriptor - field->type),
field->type, field->name,
array_descriptor, field->offset,
field->size, !!field->is_signed);
}
}
if (!printed_common_field) {
tmp_fprintf("\n");
if (ftrace_common_fields_count)
nfields = t->nfields;
else
nfields = t->nfields - default_common_field_count;
fields = t->fields;
printed_common_field = 1;
goto again;
}
tmp_fprintf("\nprint fmt: %s\n", t->print_fmt);
if (tmp_file_record_size8(fd))
return -1;
return tmp_file_flush(fd);
}
static int save_system_files(int fd, int *system_ids, int system_id)
{
int i, total = 0;
for (i = 0; i < nr_event_types; i++) {
if (system_ids[i] == system_id)
total++;
}
if (write_and_check(fd, &total, 4))
return -1;
for (i = 0; i < nr_event_types; i++) {
if (system_ids[i] != system_id)
continue;
if (save_event_file(fd, event_types[i]))
return -1;
}
return 0;
}
static int save_events_files(int fd)
{
int system_id = 1, *system_ids;
const char *system = "ftrace";
int i;
int nr_systems;
system_ids = calloc(sizeof(*system_ids), nr_event_types);
if (system_ids == NULL)
return -1;
for (;;) {
for (i = 0; i < nr_event_types; i++) {
if (system_ids[i])
continue;
if (!system) {
system = event_types[i]->system;
system_ids[i] = system_id;
continue;
}
if (!strcmp(event_types[i]->system, system))
system_ids[i] = system_id;
}
if (!system)
break;
system_id++;
system = NULL;
}
/* ftrace events */
if (save_system_files(fd, system_ids, 1))
goto fail;
/* other systems events */
nr_systems = system_id - 2;
if (write_and_check(fd, &nr_systems, 4))
goto fail;
for (system_id = 2; system_id < nr_systems + 2; system_id++) {
for (i = 0; i < nr_event_types; i++) {
if (system_ids[i] == system_id)
break;
}
if (write_and_check(fd, (void *)event_types[i]->system,
strlen(event_types[i]->system) + 1))
goto fail;
if (save_system_files(fd, system_ids, system_id))
goto fail;
}
free(system_ids);
return 0;
fail:
free(system_ids);
return -1;
}
static int save_proc_kallsyms(int fd)
{
int i;
struct syment *sp;
for (sp = st->symtable; sp < st->symend; sp++)
tmp_fprintf("%lx %c %s\n", sp->value, sp->type, sp->name);
for (i = 0; i < st->mods_installed; i++) {
struct load_module *lm = &st->load_modules[i];
for (sp = lm->mod_symtable; sp <= lm->mod_symend; sp++) {
if (!strncmp(sp->name, "_MODULE_", strlen("_MODULE_")))
continue;
/* Currently sp->type for modules is not trusted */
tmp_fprintf("%lx %c %s\t[%s]\n", sp->value, 'm',
sp->name, lm->mod_name);
}
}
if (tmp_file_record_size4(fd))
return -1;
return tmp_file_flush(fd);
}
static int add_print_address(long address)
{
char string[4096];
size_t len;
int i;
len = read_string(address, string, sizeof(string));
if (!len)
return -1;
tmp_fprintf("0x%lx : \"", address);
for (i = 0; string[i]; i++) {
switch (string[i]) {
case '\n':
tmp_fprintf("\\n");
break;
case '\t':
tmp_fprintf("\\t");
break;
case '\\':
tmp_fprintf("\\\\");
break;
case '"':
tmp_fprintf("\\\"");
break;
default:
tmp_fprintf("%c", string[i]);
}
}
tmp_fprintf("\"\n");
return 0;
}
static int save_ftrace_printk(int fd)
{
struct kernel_list_head *mod_fmt;
struct syment *s, *e, *b;
long bprintk_fmt_s, bprintk_fmt_e;
long *address;
size_t i, count;
int addr_is_array = 0;
s = symbol_search("__start___trace_bprintk_fmt");
e = symbol_search("__stop___trace_bprintk_fmt");
if (s == NULL || e == NULL)
return -1;
bprintk_fmt_s = s->value;
bprintk_fmt_e = e->value;
count = (bprintk_fmt_e - bprintk_fmt_s) / sizeof(long);
if (count == 0)
goto do_mods;
address = malloc(count * sizeof(long));
if (address == NULL)
return -1;
if (!readmem(bprintk_fmt_s, KVADDR, address, count * sizeof(long),
"get printk address", RETURN_ON_ERROR)) {
free(address);
return -1;
}
for (i = 0; i < count; i++) {
if (add_print_address(address[i]) < 0) {
free(address);
return -1;
}
}
free(address);
do_mods:
/* Add modules */
b = symbol_search("trace_bprintk_fmt_list");
if (!b)
goto out;
switch (MEMBER_TYPE("trace_bprintk_fmt", "fmt")) {
case TYPE_CODE_ARRAY:
addr_is_array = 1;
break;
case TYPE_CODE_PTR:
default:
/* default not array */
break;
}
mod_fmt = (struct kernel_list_head *)GETBUF(SIZE(list_head));
if (!readmem(b->value, KVADDR, mod_fmt,
SIZE(list_head), "trace_bprintk_fmt_list contents",
RETURN_ON_ERROR))
goto out_free;
while ((unsigned long)mod_fmt->next != b->value) {
unsigned long addr;
addr = (unsigned long)mod_fmt->next + SIZE(list_head);
if (!addr_is_array) {
if (!readmem(addr, KVADDR, &addr, sizeof(addr),
"trace_bprintk_fmt_list fmt field",
RETURN_ON_ERROR))
goto out_free;
}
if (!readmem((unsigned long)mod_fmt->next, KVADDR, mod_fmt,
SIZE(list_head), "trace_bprintk_fmt_list contents",
RETURN_ON_ERROR))
goto out_free;
if (add_print_address(addr) < 0)
goto out_free;
count++;
}
out_free:
FREEBUF(mod_fmt);
out:
if (count == 0) {
unsigned int size = 0;
return write_and_check(fd, &size, 4);
}
if (tmp_file_record_size4(fd))
return -1;
return tmp_file_flush(fd);
}
static int save_ftrace_cmdlines(int fd)
{
int i;
struct task_context *tc = FIRST_CONTEXT();
for (i = 0; i < RUNNING_TASKS(); i++)
tmp_fprintf("%d %s\n", (int)tc[i].pid, tc[i].comm);
if (tmp_file_record_size8(fd))
return -1;
return tmp_file_flush(fd);
}
/* From trace-cmd.h */
enum {
TRACECMD_OPTION_DONE, /* 0 */
TRACECMD_OPTION_DATE, /* 1 */
TRACECMD_OPTION_CPUSTAT, /* 2 */
TRACECMD_OPTION_BUFFER, /* 3 */
TRACECMD_OPTION_TRACECLOCK, /* 4 */
TRACECMD_OPTION_UNAME, /* 5 */
TRACECMD_OPTION_HOOK, /* 6 */
};
static int write_options(int fd, unsigned long long *buffer_offsets)
{
int i;
unsigned short option;
if (!multiple_instances_available)
return 0;
if (write_and_check(fd, "options ", 10))
return -1;
option = TRACECMD_OPTION_BUFFER;
for (i = 0; i < instance_count; i++)
{
char *name = trace_instances[i].name;
size_t name_size = strlen(name) + 1; /* Name length + '\0' */
unsigned long long option_size = 8 + name_size;
unsigned long long offset;
offset = buffer_offsets ? buffer_offsets[i] : 0;
if (write_and_check(fd, &option, 2))
return -1;
if (write_and_check(fd, &option_size, 4))
return -1;
if (write_and_check(fd, &offset, 8))
return -1;
if (write_and_check(fd, name, name_size))
return -1;
}
option = TRACECMD_OPTION_DONE;
if (write_and_check(fd, &option, 2))
return -1;
return 0;
}
static int save_res_data(int fd, int nr_cpu_buffers, unsigned long long *buffer_offsets)
{
if (write_and_check(fd, &nr_cpu_buffers, 4))
return -1;
if (write_options(fd, buffer_offsets))
return -1;
if (write_and_check(fd, "flyrecord", 10))
return -1;
return 0;
}
static int save_record_data(int fd, int nr_cpu_buffers, struct trace_instance *ti)
{
int i, j;
unsigned long long offset, buffer_offset;
void *page_tmp;
offset = lseek(fd, 0, SEEK_CUR);
offset += nr_cpu_buffers * 16;
offset = (offset + (PAGESIZE() - 1)) & ~(PAGESIZE() - 1);
buffer_offset = offset;
for (i = 0; i < nr_cpu_ids; i++) {
struct ring_buffer_per_cpu *cpu_buffer = &ti->buffers[i];
unsigned long long buffer_size;
if (!cpu_buffer->kaddr)
continue;
buffer_size = PAGESIZE() * cpu_buffer->nr_linear_pages;
if (write_and_check(fd, &buffer_offset, 8))
return -1;
if (write_and_check(fd, &buffer_size, 8))
return -1;
buffer_offset += buffer_size;
}
page_tmp = malloc(PAGESIZE());
if (page_tmp == NULL)
return -1;
lseek(fd, offset, SEEK_SET);
for (i = 0; i < nr_cpu_ids; i++) {
struct ring_buffer_per_cpu *cpu_buffer = &ti->buffers[i];
if (!cpu_buffer->kaddr)
continue;
for (j = 0; j < cpu_buffer->nr_linear_pages; j++) {
if (ftrace_dump_page(fd, cpu_buffer->linear_pages[j],
page_tmp) < 0) {
free(page_tmp);
return -1;
}
}
}
free(page_tmp);
return 0;
}
static int get_nr_cpu_buffers(struct trace_instance *ti)
{
int i;
int nr_cpu_buffers = 0;
for (i = 0; i < nr_cpu_ids; i++) {
struct ring_buffer_per_cpu *cpu_buffer = &ti->buffers[i];
if (!cpu_buffer->kaddr)
continue;
nr_cpu_buffers++;
}
return nr_cpu_buffers;
}
static int __trace_cmd_data_output(int fd)
{
int nr_cpu_buffers;
unsigned long long global_res_data_offset;
unsigned long long *instance_offsets;
instance_offsets = calloc(sizeof(unsigned long long), instance_count);
nr_cpu_buffers = get_nr_cpu_buffers(&global_trace_instance);
if (save_initial_data(fd))
return -1;
if (save_header_files(fd))
return -1;
if (save_events_files(fd)) /* ftrace events and other systems events */
return -1;
if (save_proc_kallsyms(fd))
return -1;
if (save_ftrace_printk(fd))
return -1;
if (save_ftrace_cmdlines(fd))
return -1;
/* We don't have the instance buffer offsets yet, so we'll write in 0s
* for now, and fix it up after we have that information available */
global_res_data_offset = lseek(fd, 0, SEEK_CUR);
if (save_res_data(fd, nr_cpu_buffers, NULL))
return -1;
if (save_record_data(fd, nr_cpu_buffers, &global_trace_instance))
return -1;
if (multiple_instances_available)
{
int i;
for (i = 0; i < instance_count; i++)
{
struct trace_instance *ti = &trace_instances[i];
nr_cpu_buffers = get_nr_cpu_buffers(ti);
/* Save off the instance offset for fixup later */
instance_offsets[i] = lseek(fd, 0, SEEK_CUR);
if (write_and_check(fd, "flyrecord", 10))
return -1;
if (save_record_data(fd, nr_cpu_buffers, ti))
return -1;
}
}
/* Fix up the global trace's options header with the instance offsets */
lseek(fd, global_res_data_offset, SEEK_SET);
nr_cpu_buffers = get_nr_cpu_buffers(&global_trace_instance);
if (save_res_data(fd, nr_cpu_buffers, instance_offsets))
return -1;
return 0;
}
static int trace_cmd_data_output(int fd)
{
int ret;
if (init_tmp_file())
return -1;
ret = __trace_cmd_data_output(fd);
destory_tmp_file();
return ret;
}