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signal: remove three noop tracehooks

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Remove the following three noop tracehooks in signals.c.

* tracehook_force_sigpending()
* tracehook_get_signal()
* tracehook_finish_jctl()

The code area is about to be updated and these hooks don't do anything
other than obfuscating the logic.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
This commit is contained in:
Tejun Heo 2011-06-02 11:14:00 +02:00 committed by Oleg Nesterov
parent 62c124ff3b
commit dd1d677269
2 changed files with 14 additions and 82 deletions
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52
include/linux/tracehook.h
View file

@ -425,58 +425,6 @@ static inline int tracehook_consider_fatal_signal(struct task_struct *task,
return (task_ptrace(task) & PT_PTRACED) != 0;
}
/**
* tracehook_force_sigpending - let tracing force signal_pending(current) on
*
* Called when recomputing our signal_pending() flag. Return nonzero
* to force the signal_pending() flag on, so that tracehook_get_signal()
* will be called before the next return to user mode.
*
* Called with @current->sighand->siglock held.
*/
static inline int tracehook_force_sigpending(void)
{
return 0;
}
/**
* tracehook_get_signal - deliver synthetic signal to traced task
* @task: @current
* @regs: task_pt_regs(@current)
* @info: details of synthetic signal
* @return_ka: sigaction for synthetic signal
*
* Return zero to check for a real pending signal normally.
* Return -1 after releasing the siglock to repeat the check.
* Return a signal number to induce an artificial signal delivery,
* setting *@info and *@return_ka to specify its details and behavior.
*
* The @return_ka->sa_handler value controls the disposition of the
* signal, no matter the signal number. For %SIG_DFL, the return value
* is a representative signal to indicate the behavior (e.g. %SIGTERM
* for death, %SIGQUIT for core dump, %SIGSTOP for job control stop,
* %SIGTSTP for stop unless in an orphaned pgrp), but the signal number
* reported will be @info->si_signo instead.
*
* Called with @task->sighand->siglock held, before dequeuing pending signals.
*/
static inline int tracehook_get_signal(struct task_struct *task,
struct pt_regs *regs,
siginfo_t *info,
struct k_sigaction *return_ka)
{
return 0;
}
/**
* tracehook_finish_jctl - report about return from job control stop
*
* This is called by do_signal_stop() after wakeup.
*/
static inline void tracehook_finish_jctl(void)
{
}
#define DEATH_REAP -1
#define DEATH_DELAYED_GROUP_LEADER -2

44
kernel/signal.c
View file

@ -150,9 +150,7 @@ void recalc_sigpending_and_wake(struct task_struct *t)
void recalc_sigpending(void)
{
if (unlikely(tracehook_force_sigpending()))
set_thread_flag(TIF_SIGPENDING);
else if (!recalc_sigpending_tsk(current) && !freezing(current))
if (!recalc_sigpending_tsk(current) && !freezing(current))
clear_thread_flag(TIF_SIGPENDING);
}
@ -2005,8 +2003,6 @@ retry:
spin_unlock_irq(&current->sighand->siglock);
tracehook_finish_jctl();
return 1;
}
@ -2109,37 +2105,25 @@ relock:
for (;;) {
struct k_sigaction *ka;
/*
* Tracing can induce an artificial signal and choose sigaction.
* The return value in @signr determines the default action,
* but @info->si_signo is the signal number we will report.
*/
signr = tracehook_get_signal(current, regs, info, return_ka);
if (unlikely(signr < 0))
if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) &&
do_signal_stop(0))
goto relock;
if (unlikely(signr != 0))
ka = return_ka;
else {
if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) &&
do_signal_stop(0))
goto relock;
signr = dequeue_signal(current, &current->blocked,
info);
signr = dequeue_signal(current, &current->blocked, info);
if (!signr)
break; /* will return 0 */
if (signr != SIGKILL) {
signr = ptrace_signal(signr, info,
regs, cookie);
if (!signr)
break; /* will return 0 */
if (signr != SIGKILL) {
signr = ptrace_signal(signr, info,
regs, cookie);
if (!signr)
continue;
}
ka = &sighand->action[signr-1];
continue;
}
ka = &sighand->action[signr-1];
/* Trace actually delivered signals. */
trace_signal_deliver(signr, info, ka);