168 строки
3.6 KiB
C
168 строки
3.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#ifndef _GNU_SOURCE
|
|
# define _GNU_SOURCE
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <linux/string.h>
|
|
#include <errno.h>
|
|
#include <unistd.h>
|
|
#include "fs.h"
|
|
|
|
#include "tracing_path.h"
|
|
|
|
static char tracing_mnt[PATH_MAX] = "/sys/kernel/debug";
|
|
static char tracing_path[PATH_MAX] = "/sys/kernel/debug/tracing";
|
|
static char tracing_events_path[PATH_MAX] = "/sys/kernel/debug/tracing/events";
|
|
|
|
static void __tracing_path_set(const char *tracing, const char *mountpoint)
|
|
{
|
|
snprintf(tracing_mnt, sizeof(tracing_mnt), "%s", mountpoint);
|
|
snprintf(tracing_path, sizeof(tracing_path), "%s/%s",
|
|
mountpoint, tracing);
|
|
snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
|
|
mountpoint, tracing, "events");
|
|
}
|
|
|
|
static const char *tracing_path_tracefs_mount(void)
|
|
{
|
|
const char *mnt;
|
|
|
|
mnt = tracefs__mount();
|
|
if (!mnt)
|
|
return NULL;
|
|
|
|
__tracing_path_set("", mnt);
|
|
|
|
return tracing_path;
|
|
}
|
|
|
|
static const char *tracing_path_debugfs_mount(void)
|
|
{
|
|
const char *mnt;
|
|
|
|
mnt = debugfs__mount();
|
|
if (!mnt)
|
|
return NULL;
|
|
|
|
__tracing_path_set("tracing/", mnt);
|
|
|
|
return tracing_path;
|
|
}
|
|
|
|
const char *tracing_path_mount(void)
|
|
{
|
|
const char *mnt;
|
|
|
|
mnt = tracing_path_tracefs_mount();
|
|
if (mnt)
|
|
return mnt;
|
|
|
|
mnt = tracing_path_debugfs_mount();
|
|
|
|
return mnt;
|
|
}
|
|
|
|
void tracing_path_set(const char *mntpt)
|
|
{
|
|
__tracing_path_set("tracing/", mntpt);
|
|
}
|
|
|
|
char *get_tracing_file(const char *name)
|
|
{
|
|
char *file;
|
|
|
|
if (asprintf(&file, "%s/%s", tracing_path_mount(), name) < 0)
|
|
return NULL;
|
|
|
|
return file;
|
|
}
|
|
|
|
void put_tracing_file(char *file)
|
|
{
|
|
free(file);
|
|
}
|
|
|
|
char *get_events_file(const char *name)
|
|
{
|
|
char *file;
|
|
|
|
if (asprintf(&file, "%s/events/%s", tracing_path_mount(), name) < 0)
|
|
return NULL;
|
|
|
|
return file;
|
|
}
|
|
|
|
void put_events_file(char *file)
|
|
{
|
|
free(file);
|
|
}
|
|
|
|
DIR *tracing_events__opendir(void)
|
|
{
|
|
DIR *dir = NULL;
|
|
char *path = get_tracing_file("events");
|
|
|
|
if (path) {
|
|
dir = opendir(path);
|
|
put_events_file(path);
|
|
}
|
|
|
|
return dir;
|
|
}
|
|
|
|
int tracing_path__strerror_open_tp(int err, char *buf, size_t size,
|
|
const char *sys, const char *name)
|
|
{
|
|
char sbuf[128];
|
|
char filename[PATH_MAX];
|
|
|
|
snprintf(filename, PATH_MAX, "%s/%s", sys, name ?: "*");
|
|
|
|
switch (err) {
|
|
case ENOENT:
|
|
/*
|
|
* We will get here if we can't find the tracepoint, but one of
|
|
* debugfs or tracefs is configured, which means you probably
|
|
* want some tracepoint which wasn't compiled in your kernel.
|
|
* - jirka
|
|
*/
|
|
if (debugfs__configured() || tracefs__configured()) {
|
|
/* sdt markers */
|
|
if (!strncmp(filename, "sdt_", 4)) {
|
|
snprintf(buf, size,
|
|
"Error:\tFile %s/%s not found.\n"
|
|
"Hint:\tSDT event cannot be directly recorded on.\n"
|
|
"\tPlease first use 'perf probe %s:%s' before recording it.\n",
|
|
tracing_events_path, filename, sys, name);
|
|
} else {
|
|
snprintf(buf, size,
|
|
"Error:\tFile %s/%s not found.\n"
|
|
"Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n",
|
|
tracing_events_path, filename);
|
|
}
|
|
break;
|
|
}
|
|
snprintf(buf, size, "%s",
|
|
"Error:\tUnable to find debugfs/tracefs\n"
|
|
"Hint:\tWas your kernel compiled with debugfs/tracefs support?\n"
|
|
"Hint:\tIs the debugfs/tracefs filesystem mounted?\n"
|
|
"Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'");
|
|
break;
|
|
case EACCES: {
|
|
snprintf(buf, size,
|
|
"Error:\tNo permissions to read %s/%s\n"
|
|
"Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n",
|
|
tracing_events_path, filename, tracing_path_mount());
|
|
}
|
|
break;
|
|
default:
|
|
snprintf(buf, size, "%s", str_error_r(err, sbuf, sizeof(sbuf)));
|
|
break;
|
|
}
|
|
|
|
return 0;
|
|
}
|