* the system call. That must prevent normal entry so no system call is
* made. If @task ever returns to user mode after this, its register state
* is unspecified, but should be something harmless like an %ENOSYS error
- * return.
+ * return. It should preserve enough information so that syscall_rollback()
+ * can work (see asm-generic/syscall.h).
*
* Called without locks, just after entering kernel mode.
*/
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 artifical 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_notify_jctl - report about job control stop/continue
+ * @notify: nonzero if this is the last thread in the group to stop
+ * @why: %CLD_STOPPED or %CLD_CONTINUED
+ *
+ * This is called when we might call do_notify_parent_cldstop().
+ * It's called when about to stop for job control; we are already in
+ * %TASK_STOPPED state, about to call schedule(). It's also called when
+ * a delayed %CLD_STOPPED or %CLD_CONTINUED report is ready to be made.
+ *
+ * Return nonzero to generate a %SIGCHLD with @why, which is
+ * normal if @notify is nonzero.
+ *
+ * Called with no locks held.
+ */
+static inline int tracehook_notify_jctl(int notify, int why)
+{
+ return notify || (current->ptrace & PT_PTRACED);
+}
+
+/**
+ * tracehook_notify_death - task is dead, ready to notify parent
+ * @task: @current task now exiting
+ * @death_cookie: value to pass to tracehook_report_death()
+ * @group_dead: nonzero if this was the last thread in the group to die
+ *
+ * Return the signal number to send our parent with do_notify_parent(), or
+ * zero to send no signal and leave a zombie, or -1 to self-reap right now.
+ *
+ * Called with write_lock_irq(&tasklist_lock) held.
+ */
+static inline int tracehook_notify_death(struct task_struct *task,
+ void **death_cookie, int group_dead)
+{
+ if (task->exit_signal == -1)
+ return task->ptrace ? SIGCHLD : -1;
+
+ /*
+ * If something other than our normal parent is ptracing us, then
+ * send it a SIGCHLD instead of honoring exit_signal. exit_signal
+ * only has special meaning to our real parent.
+ */
+ if (thread_group_empty(task) && !ptrace_reparented(task))
+ return task->exit_signal;
+
+ return task->ptrace ? SIGCHLD : 0;
+}
+
+/**
+ * tracehook_report_death - task is dead and ready to be reaped
+ * @task: @current task now exiting
+ * @signal: signal number sent to parent, or 0 or -1
+ * @death_cookie: value passed back from tracehook_notify_death()
+ * @group_dead: nonzero if this was the last thread in the group to die
+ *
+ * Thread has just become a zombie or is about to self-reap. If positive,
+ * @signal is the signal number just sent to the parent (usually %SIGCHLD).
+ * If @signal is -1, this thread will self-reap. If @signal is 0, this is
+ * a delayed_group_leader() zombie. The @death_cookie was passed back by
+ * tracehook_notify_death().
+ *
+ * If normal reaping is not inhibited, @task->exit_state might be changing
+ * in parallel.
+ *
+ * Called without locks.
+ */
+static inline void tracehook_report_death(struct task_struct *task,
+ int signal, void *death_cookie,
+ int group_dead)
+{
+}
+
+#ifdef TIF_NOTIFY_RESUME
+/**
+ * set_notify_resume - cause tracehook_notify_resume() to be called
+ * @task: task that will call tracehook_notify_resume()
+ *
+ * Calling this arranges that @task will call tracehook_notify_resume()
+ * before returning to user mode. If it's already running in user mode,
+ * it will enter the kernel and call tracehook_notify_resume() soon.
+ * If it's blocked, it will not be woken.
+ */
+static inline void set_notify_resume(struct task_struct *task)
+{
+ if (!test_and_set_tsk_thread_flag(task, TIF_NOTIFY_RESUME))
+ kick_process(task);
+}
+
+/**
+ * tracehook_notify_resume - report when about to return to user mode
+ * @regs: user-mode registers of @current task
+ *
+ * This is called when %TIF_NOTIFY_RESUME has been set. Now we are
+ * about to return to user mode, and the user state in @regs can be
+ * inspected or adjusted. The caller in arch code has cleared
+ * %TIF_NOTIFY_RESUME before the call. If the flag gets set again
+ * asynchronously, this will be called again before we return to
+ * user mode.
+ *
+ * Called without locks.
+ */
+static inline void tracehook_notify_resume(struct pt_regs *regs)
+{
+}
+#endif /* TIF_NOTIFY_RESUME */
+
#endif /* <linux/tracehook.h> */
projects / linux-2.6-omap-h63xx.git / blobdiff