linux/tools/perf/util/perf-hooks.c

91 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* perf_hooks.c
*
* Copyright (C) 2016 Wang Nan <wangnan0@huawei.com>
* Copyright (C) 2016 Huawei Inc.
*/
#include <errno.h>
#include <stdlib.h>
#include <setjmp.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include "util/util.h"
#include "util/debug.h"
#include "util/perf-hooks.h"
static sigjmp_buf jmpbuf;
static const struct perf_hook_desc *current_perf_hook;
void perf_hooks__invoke(const struct perf_hook_desc *desc)
{
if (!(desc && desc->p_hook_func && *desc->p_hook_func))
return;
if (sigsetjmp(jmpbuf, 1)) {
pr_warning("Fatal error (SEGFAULT) in perf hook '%s'\n",
desc->hook_name);
*(current_perf_hook->p_hook_func) = NULL;
} else {
current_perf_hook = desc;
(**desc->p_hook_func)(desc->hook_ctx);
}
current_perf_hook = NULL;
}
void perf_hooks__recover(void)
{
if (current_perf_hook)
siglongjmp(jmpbuf, 1);
}
#define PERF_HOOK(name) \
perf_hook_func_t __perf_hook_func_##name = NULL; \
struct perf_hook_desc __perf_hook_desc_##name = \
{.hook_name = #name, \
.p_hook_func = &__perf_hook_func_##name, \
.hook_ctx = NULL};
#include "perf-hooks-list.h"
#undef PERF_HOOK
#define PERF_HOOK(name) \
&__perf_hook_desc_##name,
static struct perf_hook_desc *perf_hooks[] = {
#include "perf-hooks-list.h"
};
#undef PERF_HOOK
int perf_hooks__set_hook(const char *hook_name,
perf_hook_func_t hook_func,
void *hook_ctx)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(perf_hooks); i++) {
if (strcmp(hook_name, perf_hooks[i]->hook_name) != 0)
continue;
if (*(perf_hooks[i]->p_hook_func))
pr_warning("Overwrite existing hook: %s\n", hook_name);
*(perf_hooks[i]->p_hook_func) = hook_func;
perf_hooks[i]->hook_ctx = hook_ctx;
return 0;
}
return -ENOENT;
}
perf_hook_func_t perf_hooks__get_hook(const char *hook_name)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(perf_hooks); i++) {
if (strcmp(hook_name, perf_hooks[i]->hook_name) != 0)
continue;
return *(perf_hooks[i]->p_hook_func);
}
return ERR_PTR(-ENOENT);
}