/* $Id: misc.c,v 1.26 2006/08/27 07:34:41 mikpe Exp $
* Miscellaneous perfctr operations.
*
* Copyright (C) 1999-2004 Mikael Pettersson
*/
#include <sys/utsname.h>
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libperfctr.h"
#include "arch.h"
#define SYS_CLASS_PERFCTR "/sys/class/perfctr/"
static int read_uint(const char *path, unsigned int *dst)
{
FILE *fp;
int ret;
fp = fopen(path, "r");
if (!fp)
return -1;
ret = fscanf(fp, "%i", (int*)dst);
fclose(fp);
return (ret == 1) ? 0 : -1;
}
static int read_string(const char *path, char *dst, size_t dstlen)
{
FILE *fp;
int len;
fp = fopen(path, "r");
if (!fp)
return -1;
len = 0;
while (len < dstlen) {
int ch = fgetc(fp);
switch (ch) {
case '\n':
case '\0':
break;
default:
dst[len++] = ch;
continue;
}
break;
}
if (len < dstlen)
dst[len] = '\0';
fclose(fp);
return 0;
}
static int read_cpumask(const char *path, struct perfctr_cpu_mask *mask)
{
unsigned int nrwords;
if (!mask)
return 0;
/* XXX: fake */
nrwords = mask->nrwords;
mask->nrwords = 1;
if (nrwords) {
mask->mask[0] = 0;
return 0;
} else {
errno = EOVERFLOW;
return -1;
}
}
static int read_info(struct perfctr_info *info)
{
int err = 0;
if (!info)
return 0;
#if 0
err |= read_uint(SYS_CLASS_PERFCTR "abi_version", &info->abi_version);
#else
info->abi_version = PERFCTR_ABI_VERSION;
#endif
// err |= read_uint(SYS_CLASS_PERFCTR "cpu_type", &info->cpu_type);
err |= read_uint(SYS_CLASS_PERFCTR "cpu_features", &info->cpu_features);
err |= read_uint(SYS_CLASS_PERFCTR "cpu_khz", &info->cpu_khz);
err |= read_uint(SYS_CLASS_PERFCTR "tsc_to_cpu_mult", &info->tsc_to_cpu_mult);
err |= read_string(SYS_CLASS_PERFCTR "driver_version",
info->driver_version, sizeof(info->driver_version));
return err;
}
int _perfctr_get_state_user_offset(void)
{
unsigned int offset;
if (read_uint(SYS_CLASS_PERFCTR "state_user_offset", &offset) != 0)
return -1;
return offset;
}
int _sys_perfctr_info(int fd_unused,
struct perfctr_info *info,
struct perfctr_cpu_mask *cpus,
struct perfctr_cpu_mask *forbidden)
{
int err = 0;
err |= read_info(info);
err |= read_cpumask(SYS_CLASS_PERFCTR "cpus_online", cpus);
err |= read_cpumask(SYS_CLASS_PERFCTR "cpus_forbidden", forbidden);
return err;
}
int _perfctr_abi_check_fd(int fd, unsigned int user_abi_version)
{
struct perfctr_info info;
if( _sys_perfctr_info(fd, &info, NULL, NULL) < 0 ) {
perror("perfctr_abi_check");
return -1;
}
if( (info.abi_version ^ user_abi_version) & 0xFF00FF00 ) {
fprintf(stderr, "Error: perfctr ABI major version mismatch: "
"driver ABI 0x%08X, user ABI 0x%08X\n",
info.abi_version, user_abi_version);
errno = EPROTO;
return -1;
}
return 0;
}
int perfctr_info(int fd, struct perfctr_info *info)
{
if( _sys_perfctr_info(fd, info, NULL, NULL) < 0 )
return -1;
perfctr_info_cpu_init(info);
return 0;
}
struct perfctr_cpus_info *perfctr_cpus_info(int fd)
{
struct perfctr_cpu_mask dummy;
struct perfctr_cpus_info *info;
unsigned int cpu_mask_bytes;
dummy.nrwords = 0;
if( _sys_perfctr_info(fd, NULL, &dummy, NULL) >= 0 ||
errno != EOVERFLOW ||
dummy.nrwords == 0 ) {
perror("PERFCTR_CPUS");
return NULL;
}
cpu_mask_bytes = offsetof(struct perfctr_cpu_mask, mask[dummy.nrwords]);
info = malloc(sizeof(struct perfctr_cpus_info) + 2*cpu_mask_bytes);
if( !info ) {
perror("malloc");
return NULL;
}
info->cpus = (struct perfctr_cpu_mask*)(info + 1);
info->cpus->nrwords = dummy.nrwords;
info->cpus_forbidden = (struct perfctr_cpu_mask*)((char*)(info + 1) + cpu_mask_bytes);
info->cpus_forbidden->nrwords = dummy.nrwords;
if( _sys_perfctr_info(fd, NULL, info->cpus, info->cpus_forbidden) < 0 ) {
perror("PERFCTR_CPUS");
free(info);
return NULL;
}
return info;
}
void perfctr_info_print(const struct perfctr_info *info)
{
static const char * const features[] = { "rdpmc", "rdtsc", "pcint" };
int fi, comma;
printf("abi_version\t\t0x%08X\n", info->abi_version);
printf("driver_version\t\t%s\n", info->driver_version);
printf("cpu_type\t\t%u (%s)\n", info->cpu_type, perfctr_info_cpu_name(info));
printf("cpu_features\t\t%#x (", info->cpu_features);
for(comma = 0, fi = 0; fi < sizeof features / sizeof features[0]; ++fi) {
unsigned fmask = 1 << fi;
if( info->cpu_features & fmask ) {
if( comma )
printf(",");
printf("%s", features[fi]);
comma = 1;
}
}
printf(")\n");
printf("cpu_khz\t\t\t%u\n", info->cpu_khz);
printf("tsc_to_cpu_mult\t\t%u%s\n",
info->tsc_to_cpu_mult,
info->tsc_to_cpu_mult ? "" : " (unspecified, assume 1)");
printf("cpu_nrctrs\t\t%u\n", perfctr_info_nrctrs(info));
}
static void print_cpus(const struct perfctr_cpu_mask *cpus)
{
unsigned int nrcpus, nr, i, cpumask, bitmask;
printf("[");
nrcpus = 0;
for(i = 0; i < cpus->nrwords; ++i) {
cpumask = cpus->mask[i];
nr = i * 8 * sizeof(int);
for(bitmask = 1; cpumask != 0; ++nr, bitmask <<= 1) {
if( cpumask & bitmask ) {
cpumask &= ~bitmask;
if( nrcpus )
printf(",");
++nrcpus;
printf("%u", nr);
}
}
}
printf("], total: %u\n", nrcpus);
}
void perfctr_cpus_info_print(const struct perfctr_cpus_info *info)
{
printf("cpus\t\t\t"); print_cpus(info->cpus);
printf("cpus_forbidden\t\t"); print_cpus(info->cpus_forbidden);
}
unsigned int perfctr_linux_version_code(void)
{
struct utsname utsname;
unsigned int version, patchlevel, sublevel;
if (uname(&utsname) < 0) {
fprintf(stderr, "uname: %s\n", strerror(errno));
return 0;
}
if (sscanf(utsname.release, "%u.%u.%u", &version, &patchlevel, &sublevel) != 3) {
fprintf(stderr, "uname: unexpected release '%s'\n", utsname.release);
return 0;
}
return PERFCTR_KERNEL_VERSION(version,patchlevel,sublevel);
}