mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
![Will Deacon](/assets/img/avatar_default.png)
syscall_get_nr can return -1 in the case that the task is not executing a system call. This patch fixes perf_syscall_{enter,exit} to check that the syscall number is valid before using it as an index into a bitmap. Link: http://lkml.kernel.org/r/1345137254-7377-1-git-send-email-will.deacon@arm.com Cc: Jason Baron <jbaron@redhat.com> Cc: Wade Farnsworth <wade_farnsworth@mentor.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
705 lines
17 KiB
C
705 lines
17 KiB
C
#include <trace/syscall.h>
|
|
#include <trace/events/syscalls.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */
|
|
#include <linux/ftrace.h>
|
|
#include <linux/perf_event.h>
|
|
#include <asm/syscall.h>
|
|
|
|
#include "trace_output.h"
|
|
#include "trace.h"
|
|
|
|
static DEFINE_MUTEX(syscall_trace_lock);
|
|
static int sys_refcount_enter;
|
|
static int sys_refcount_exit;
|
|
static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
|
|
static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
|
|
|
|
static int syscall_enter_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data);
|
|
static int syscall_exit_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data);
|
|
|
|
static int syscall_enter_define_fields(struct ftrace_event_call *call);
|
|
static int syscall_exit_define_fields(struct ftrace_event_call *call);
|
|
|
|
static struct list_head *
|
|
syscall_get_enter_fields(struct ftrace_event_call *call)
|
|
{
|
|
struct syscall_metadata *entry = call->data;
|
|
|
|
return &entry->enter_fields;
|
|
}
|
|
|
|
struct trace_event_functions enter_syscall_print_funcs = {
|
|
.trace = print_syscall_enter,
|
|
};
|
|
|
|
struct trace_event_functions exit_syscall_print_funcs = {
|
|
.trace = print_syscall_exit,
|
|
};
|
|
|
|
struct ftrace_event_class event_class_syscall_enter = {
|
|
.system = "syscalls",
|
|
.reg = syscall_enter_register,
|
|
.define_fields = syscall_enter_define_fields,
|
|
.get_fields = syscall_get_enter_fields,
|
|
.raw_init = init_syscall_trace,
|
|
};
|
|
|
|
struct ftrace_event_class event_class_syscall_exit = {
|
|
.system = "syscalls",
|
|
.reg = syscall_exit_register,
|
|
.define_fields = syscall_exit_define_fields,
|
|
.fields = LIST_HEAD_INIT(event_class_syscall_exit.fields),
|
|
.raw_init = init_syscall_trace,
|
|
};
|
|
|
|
extern struct syscall_metadata *__start_syscalls_metadata[];
|
|
extern struct syscall_metadata *__stop_syscalls_metadata[];
|
|
|
|
static struct syscall_metadata **syscalls_metadata;
|
|
|
|
#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
|
|
static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
|
|
{
|
|
/*
|
|
* Only compare after the "sys" prefix. Archs that use
|
|
* syscall wrappers may have syscalls symbols aliases prefixed
|
|
* with "SyS" instead of "sys", leading to an unwanted
|
|
* mismatch.
|
|
*/
|
|
return !strcmp(sym + 3, name + 3);
|
|
}
|
|
#endif
|
|
|
|
static __init struct syscall_metadata *
|
|
find_syscall_meta(unsigned long syscall)
|
|
{
|
|
struct syscall_metadata **start;
|
|
struct syscall_metadata **stop;
|
|
char str[KSYM_SYMBOL_LEN];
|
|
|
|
|
|
start = __start_syscalls_metadata;
|
|
stop = __stop_syscalls_metadata;
|
|
kallsyms_lookup(syscall, NULL, NULL, NULL, str);
|
|
|
|
if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
|
|
return NULL;
|
|
|
|
for ( ; start < stop; start++) {
|
|
if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
|
|
return *start;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static struct syscall_metadata *syscall_nr_to_meta(int nr)
|
|
{
|
|
if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
|
|
return NULL;
|
|
|
|
return syscalls_metadata[nr];
|
|
}
|
|
|
|
enum print_line_t
|
|
print_syscall_enter(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_entry *ent = iter->ent;
|
|
struct syscall_trace_enter *trace;
|
|
struct syscall_metadata *entry;
|
|
int i, ret, syscall;
|
|
|
|
trace = (typeof(trace))ent;
|
|
syscall = trace->nr;
|
|
entry = syscall_nr_to_meta(syscall);
|
|
|
|
if (!entry)
|
|
goto end;
|
|
|
|
if (entry->enter_event->event.type != ent->type) {
|
|
WARN_ON_ONCE(1);
|
|
goto end;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, "%s(", entry->name);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
for (i = 0; i < entry->nb_args; i++) {
|
|
/* parameter types */
|
|
if (trace_flags & TRACE_ITER_VERBOSE) {
|
|
ret = trace_seq_printf(s, "%s ", entry->types[i]);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
/* parameter values */
|
|
ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i],
|
|
trace->args[i],
|
|
i == entry->nb_args - 1 ? "" : ", ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
ret = trace_seq_putc(s, ')');
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
end:
|
|
ret = trace_seq_putc(s, '\n');
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
enum print_line_t
|
|
print_syscall_exit(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_entry *ent = iter->ent;
|
|
struct syscall_trace_exit *trace;
|
|
int syscall;
|
|
struct syscall_metadata *entry;
|
|
int ret;
|
|
|
|
trace = (typeof(trace))ent;
|
|
syscall = trace->nr;
|
|
entry = syscall_nr_to_meta(syscall);
|
|
|
|
if (!entry) {
|
|
trace_seq_printf(s, "\n");
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
if (entry->exit_event->event.type != ent->type) {
|
|
WARN_ON_ONCE(1);
|
|
return TRACE_TYPE_UNHANDLED;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
|
|
trace->ret);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
extern char *__bad_type_size(void);
|
|
|
|
#define SYSCALL_FIELD(type, name) \
|
|
sizeof(type) != sizeof(trace.name) ? \
|
|
__bad_type_size() : \
|
|
#type, #name, offsetof(typeof(trace), name), \
|
|
sizeof(trace.name), is_signed_type(type)
|
|
|
|
static
|
|
int __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
|
|
{
|
|
int i;
|
|
int pos = 0;
|
|
|
|
/* When len=0, we just calculate the needed length */
|
|
#define LEN_OR_ZERO (len ? len - pos : 0)
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
|
|
for (i = 0; i < entry->nb_args; i++) {
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
|
|
entry->args[i], sizeof(unsigned long),
|
|
i == entry->nb_args - 1 ? "" : ", ");
|
|
}
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
|
|
|
|
for (i = 0; i < entry->nb_args; i++) {
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO,
|
|
", ((unsigned long)(REC->%s))", entry->args[i]);
|
|
}
|
|
|
|
#undef LEN_OR_ZERO
|
|
|
|
/* return the length of print_fmt */
|
|
return pos;
|
|
}
|
|
|
|
static int set_syscall_print_fmt(struct ftrace_event_call *call)
|
|
{
|
|
char *print_fmt;
|
|
int len;
|
|
struct syscall_metadata *entry = call->data;
|
|
|
|
if (entry->enter_event != call) {
|
|
call->print_fmt = "\"0x%lx\", REC->ret";
|
|
return 0;
|
|
}
|
|
|
|
/* First: called with 0 length to calculate the needed length */
|
|
len = __set_enter_print_fmt(entry, NULL, 0);
|
|
|
|
print_fmt = kmalloc(len + 1, GFP_KERNEL);
|
|
if (!print_fmt)
|
|
return -ENOMEM;
|
|
|
|
/* Second: actually write the @print_fmt */
|
|
__set_enter_print_fmt(entry, print_fmt, len + 1);
|
|
call->print_fmt = print_fmt;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void free_syscall_print_fmt(struct ftrace_event_call *call)
|
|
{
|
|
struct syscall_metadata *entry = call->data;
|
|
|
|
if (entry->enter_event == call)
|
|
kfree(call->print_fmt);
|
|
}
|
|
|
|
static int syscall_enter_define_fields(struct ftrace_event_call *call)
|
|
{
|
|
struct syscall_trace_enter trace;
|
|
struct syscall_metadata *meta = call->data;
|
|
int ret;
|
|
int i;
|
|
int offset = offsetof(typeof(trace), args);
|
|
|
|
ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
|
|
if (ret)
|
|
return ret;
|
|
|
|
for (i = 0; i < meta->nb_args; i++) {
|
|
ret = trace_define_field(call, meta->types[i],
|
|
meta->args[i], offset,
|
|
sizeof(unsigned long), 0,
|
|
FILTER_OTHER);
|
|
offset += sizeof(unsigned long);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int syscall_exit_define_fields(struct ftrace_event_call *call)
|
|
{
|
|
struct syscall_trace_exit trace;
|
|
int ret;
|
|
|
|
ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = trace_define_field(call, SYSCALL_FIELD(long, ret),
|
|
FILTER_OTHER);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
|
|
{
|
|
struct syscall_trace_enter *entry;
|
|
struct syscall_metadata *sys_data;
|
|
struct ring_buffer_event *event;
|
|
struct ring_buffer *buffer;
|
|
int size;
|
|
int syscall_nr;
|
|
|
|
syscall_nr = syscall_get_nr(current, regs);
|
|
if (syscall_nr < 0)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_enter_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
|
|
|
|
event = trace_current_buffer_lock_reserve(&buffer,
|
|
sys_data->enter_event->event.type, size, 0, 0);
|
|
if (!event)
|
|
return;
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
entry->nr = syscall_nr;
|
|
syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
|
|
|
|
if (!filter_current_check_discard(buffer, sys_data->enter_event,
|
|
entry, event))
|
|
trace_current_buffer_unlock_commit(buffer, event, 0, 0);
|
|
}
|
|
|
|
void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
|
|
{
|
|
struct syscall_trace_exit *entry;
|
|
struct syscall_metadata *sys_data;
|
|
struct ring_buffer_event *event;
|
|
struct ring_buffer *buffer;
|
|
int syscall_nr;
|
|
|
|
syscall_nr = syscall_get_nr(current, regs);
|
|
if (syscall_nr < 0)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_exit_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
event = trace_current_buffer_lock_reserve(&buffer,
|
|
sys_data->exit_event->event.type, sizeof(*entry), 0, 0);
|
|
if (!event)
|
|
return;
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
entry->nr = syscall_nr;
|
|
entry->ret = syscall_get_return_value(current, regs);
|
|
|
|
if (!filter_current_check_discard(buffer, sys_data->exit_event,
|
|
entry, event))
|
|
trace_current_buffer_unlock_commit(buffer, event, 0, 0);
|
|
}
|
|
|
|
int reg_event_syscall_enter(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
|
|
return -ENOSYS;
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_refcount_enter)
|
|
ret = register_trace_sys_enter(ftrace_syscall_enter, NULL);
|
|
if (!ret) {
|
|
set_bit(num, enabled_enter_syscalls);
|
|
sys_refcount_enter++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
void unreg_event_syscall_enter(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
|
|
return;
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_refcount_enter--;
|
|
clear_bit(num, enabled_enter_syscalls);
|
|
if (!sys_refcount_enter)
|
|
unregister_trace_sys_enter(ftrace_syscall_enter, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
int reg_event_syscall_exit(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
|
|
return -ENOSYS;
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_refcount_exit)
|
|
ret = register_trace_sys_exit(ftrace_syscall_exit, NULL);
|
|
if (!ret) {
|
|
set_bit(num, enabled_exit_syscalls);
|
|
sys_refcount_exit++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
void unreg_event_syscall_exit(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
|
|
return;
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_refcount_exit--;
|
|
clear_bit(num, enabled_exit_syscalls);
|
|
if (!sys_refcount_exit)
|
|
unregister_trace_sys_exit(ftrace_syscall_exit, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
int init_syscall_trace(struct ftrace_event_call *call)
|
|
{
|
|
int id;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
if (num < 0 || num >= NR_syscalls) {
|
|
pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
|
|
((struct syscall_metadata *)call->data)->name);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
if (set_syscall_print_fmt(call) < 0)
|
|
return -ENOMEM;
|
|
|
|
id = trace_event_raw_init(call);
|
|
|
|
if (id < 0) {
|
|
free_syscall_print_fmt(call);
|
|
return id;
|
|
}
|
|
|
|
return id;
|
|
}
|
|
|
|
unsigned long __init __weak arch_syscall_addr(int nr)
|
|
{
|
|
return (unsigned long)sys_call_table[nr];
|
|
}
|
|
|
|
int __init init_ftrace_syscalls(void)
|
|
{
|
|
struct syscall_metadata *meta;
|
|
unsigned long addr;
|
|
int i;
|
|
|
|
syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
|
|
GFP_KERNEL);
|
|
if (!syscalls_metadata) {
|
|
WARN_ON(1);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
for (i = 0; i < NR_syscalls; i++) {
|
|
addr = arch_syscall_addr(i);
|
|
meta = find_syscall_meta(addr);
|
|
if (!meta)
|
|
continue;
|
|
|
|
meta->syscall_nr = i;
|
|
syscalls_metadata[i] = meta;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
core_initcall(init_ftrace_syscalls);
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
|
|
static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
|
|
static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
|
|
static int sys_perf_refcount_enter;
|
|
static int sys_perf_refcount_exit;
|
|
|
|
static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
|
|
{
|
|
struct syscall_metadata *sys_data;
|
|
struct syscall_trace_enter *rec;
|
|
struct hlist_head *head;
|
|
int syscall_nr;
|
|
int rctx;
|
|
int size;
|
|
|
|
syscall_nr = syscall_get_nr(current, regs);
|
|
if (syscall_nr < 0)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
/* get the size after alignment with the u32 buffer size field */
|
|
size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
|
|
size = ALIGN(size + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
|
"perf buffer not large enough"))
|
|
return;
|
|
|
|
rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
|
|
sys_data->enter_event->event.type, regs, &rctx);
|
|
if (!rec)
|
|
return;
|
|
|
|
rec->nr = syscall_nr;
|
|
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
|
|
(unsigned long *)&rec->args);
|
|
|
|
head = this_cpu_ptr(sys_data->enter_event->perf_events);
|
|
perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
|
|
}
|
|
|
|
int perf_sysenter_enable(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_perf_refcount_enter)
|
|
ret = register_trace_sys_enter(perf_syscall_enter, NULL);
|
|
if (ret) {
|
|
pr_info("event trace: Could not activate"
|
|
"syscall entry trace point");
|
|
} else {
|
|
set_bit(num, enabled_perf_enter_syscalls);
|
|
sys_perf_refcount_enter++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
void perf_sysenter_disable(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_perf_refcount_enter--;
|
|
clear_bit(num, enabled_perf_enter_syscalls);
|
|
if (!sys_perf_refcount_enter)
|
|
unregister_trace_sys_enter(perf_syscall_enter, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
|
|
{
|
|
struct syscall_metadata *sys_data;
|
|
struct syscall_trace_exit *rec;
|
|
struct hlist_head *head;
|
|
int syscall_nr;
|
|
int rctx;
|
|
int size;
|
|
|
|
syscall_nr = syscall_get_nr(current, regs);
|
|
if (syscall_nr < 0)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
/* We can probably do that at build time */
|
|
size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
|
|
/*
|
|
* Impossible, but be paranoid with the future
|
|
* How to put this check outside runtime?
|
|
*/
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
|
"exit event has grown above perf buffer size"))
|
|
return;
|
|
|
|
rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
|
|
sys_data->exit_event->event.type, regs, &rctx);
|
|
if (!rec)
|
|
return;
|
|
|
|
rec->nr = syscall_nr;
|
|
rec->ret = syscall_get_return_value(current, regs);
|
|
|
|
head = this_cpu_ptr(sys_data->exit_event->perf_events);
|
|
perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
|
|
}
|
|
|
|
int perf_sysexit_enable(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_perf_refcount_exit)
|
|
ret = register_trace_sys_exit(perf_syscall_exit, NULL);
|
|
if (ret) {
|
|
pr_info("event trace: Could not activate"
|
|
"syscall exit trace point");
|
|
} else {
|
|
set_bit(num, enabled_perf_exit_syscalls);
|
|
sys_perf_refcount_exit++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
void perf_sysexit_disable(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_perf_refcount_exit--;
|
|
clear_bit(num, enabled_perf_exit_syscalls);
|
|
if (!sys_perf_refcount_exit)
|
|
unregister_trace_sys_exit(perf_syscall_exit, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
static int syscall_enter_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data)
|
|
{
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return reg_event_syscall_enter(event);
|
|
case TRACE_REG_UNREGISTER:
|
|
unreg_event_syscall_enter(event);
|
|
return 0;
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return perf_sysenter_enable(event);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
perf_sysenter_disable(event);
|
|
return 0;
|
|
case TRACE_REG_PERF_OPEN:
|
|
case TRACE_REG_PERF_CLOSE:
|
|
case TRACE_REG_PERF_ADD:
|
|
case TRACE_REG_PERF_DEL:
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int syscall_exit_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data)
|
|
{
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return reg_event_syscall_exit(event);
|
|
case TRACE_REG_UNREGISTER:
|
|
unreg_event_syscall_exit(event);
|
|
return 0;
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return perf_sysexit_enable(event);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
perf_sysexit_disable(event);
|
|
return 0;
|
|
case TRACE_REG_PERF_OPEN:
|
|
case TRACE_REG_PERF_CLOSE:
|
|
case TRACE_REG_PERF_ADD:
|
|
case TRACE_REG_PERF_DEL:
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|