WSL2-Linux-Kernel/tools/perf/util/header.c

243 строки
4.4 KiB
C

#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include "util.h"
#include "header.h"
/*
*
*/
struct perf_header_attr *perf_header_attr__new(struct perf_counter_attr *attr)
{
struct perf_header_attr *self = malloc(sizeof(*self));
if (!self)
die("nomem");
self->attr = *attr;
self->ids = 0;
self->size = 1;
self->id = malloc(sizeof(u64));
if (!self->id)
die("nomem");
return self;
}
void perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
{
int pos = self->ids;
self->ids++;
if (self->ids > self->size) {
self->size *= 2;
self->id = realloc(self->id, self->size * sizeof(u64));
if (!self->id)
die("nomem");
}
self->id[pos] = id;
}
/*
*
*/
struct perf_header *perf_header__new(void)
{
struct perf_header *self = malloc(sizeof(*self));
if (!self)
die("nomem");
self->frozen = 0;
self->attrs = 0;
self->size = 1;
self->attr = malloc(sizeof(void *));
if (!self->attr)
die("nomem");
self->data_offset = 0;
self->data_size = 0;
return self;
}
void perf_header__add_attr(struct perf_header *self,
struct perf_header_attr *attr)
{
int pos = self->attrs;
if (self->frozen)
die("frozen");
self->attrs++;
if (self->attrs > self->size) {
self->size *= 2;
self->attr = realloc(self->attr, self->size * sizeof(void *));
if (!self->attr)
die("nomem");
}
self->attr[pos] = attr;
}
static const char *__perf_magic = "PERFFILE";
#define PERF_MAGIC (*(u64 *)__perf_magic)
struct perf_file_section {
u64 offset;
u64 size;
};
struct perf_file_attr {
struct perf_counter_attr attr;
struct perf_file_section ids;
};
struct perf_file_header {
u64 magic;
u64 size;
u64 attr_size;
struct perf_file_section attrs;
struct perf_file_section data;
};
static void do_write(int fd, void *buf, size_t size)
{
while (size) {
int ret = write(fd, buf, size);
if (ret < 0)
die("failed to write");
size -= ret;
buf += ret;
}
}
void perf_header__write(struct perf_header *self, int fd)
{
struct perf_file_header f_header;
struct perf_file_attr f_attr;
struct perf_header_attr *attr;
int i;
lseek(fd, sizeof(f_header), SEEK_SET);
for (i = 0; i < self->attrs; i++) {
attr = self->attr[i];
attr->id_offset = lseek(fd, 0, SEEK_CUR);
do_write(fd, attr->id, attr->ids * sizeof(u64));
}
self->attr_offset = lseek(fd, 0, SEEK_CUR);
for (i = 0; i < self->attrs; i++) {
attr = self->attr[i];
f_attr = (struct perf_file_attr){
.attr = attr->attr,
.ids = {
.offset = attr->id_offset,
.size = attr->ids * sizeof(u64),
}
};
do_write(fd, &f_attr, sizeof(f_attr));
}
self->data_offset = lseek(fd, 0, SEEK_CUR);
f_header = (struct perf_file_header){
.magic = PERF_MAGIC,
.size = sizeof(f_header),
.attr_size = sizeof(f_attr),
.attrs = {
.offset = self->attr_offset,
.size = self->attrs * sizeof(f_attr),
},
.data = {
.offset = self->data_offset,
.size = self->data_size,
},
};
lseek(fd, 0, SEEK_SET);
do_write(fd, &f_header, sizeof(f_header));
lseek(fd, self->data_offset + self->data_size, SEEK_SET);
self->frozen = 1;
}
static void do_read(int fd, void *buf, size_t size)
{
while (size) {
int ret = read(fd, buf, size);
if (ret < 0)
die("failed to read");
size -= ret;
buf += ret;
}
}
struct perf_header *perf_header__read(int fd)
{
struct perf_header *self = perf_header__new();
struct perf_file_header f_header;
struct perf_file_attr f_attr;
u64 f_id;
int nr_attrs, nr_ids, i, j;
lseek(fd, 0, SEEK_SET);
do_read(fd, &f_header, sizeof(f_header));
if (f_header.magic != PERF_MAGIC ||
f_header.size != sizeof(f_header) ||
f_header.attr_size != sizeof(f_attr))
die("incompatible file format");
nr_attrs = f_header.attrs.size / sizeof(f_attr);
lseek(fd, f_header.attrs.offset, SEEK_SET);
for (i = 0; i < nr_attrs; i++) {
struct perf_header_attr *attr;
off_t tmp = lseek(fd, 0, SEEK_CUR);
do_read(fd, &f_attr, sizeof(f_attr));
attr = perf_header_attr__new(&f_attr.attr);
nr_ids = f_attr.ids.size / sizeof(u64);
lseek(fd, f_attr.ids.offset, SEEK_SET);
for (j = 0; j < nr_ids; j++) {
do_read(fd, &f_id, sizeof(f_id));
perf_header_attr__add_id(attr, f_id);
}
perf_header__add_attr(self, attr);
lseek(fd, tmp, SEEK_SET);
}
self->data_offset = f_header.data.offset;
self->data_size = f_header.data.size;
lseek(fd, self->data_offset + self->data_size, SEEK_SET);
self->frozen = 1;
return self;
}