Introduce the "utrace-friendly" ptrace_wake_up() and use it instead of
wake_up_process().
Kill ptrace_untrace(), detach should wake up the tracee correctly via
UTRACE_DETACH.
---
kernel/ptrace.c | 47 ++++++++++++++++++++---------------------------
1 file changed, 20 insertions(+), 27 deletions(-)
--- MINI/kernel/ptrace.c~5_WAKEUP 2009-08-25 17:54:50.000000000 +0200
+++ MINI/kernel/ptrace.c 2009-08-25 18:09:38.000000000 +0200
@@ -98,6 +98,25 @@ void xxx_ptrace_notify_stop(struct task_
utrace_engine_put(engine);
}
+static void ptrace_wake_up(struct task_struct *task)
+{
+ struct utrace_engine *engine;
+
+ engine = utrace_attach_task(task, UTRACE_ATTACH_MATCH_OPS,
+ &ptrace_utrace_ops, NULL);
+ if (unlikely(IS_ERR(engine)))
+ return;
+
+ if (task_is_stopped_or_traced(task)) {
+ spin_lock_irq(&task->sighand->siglock);
+ task->signal->flags &= ~SIGNAL_STOP_STOPPED;
+ spin_unlock_irq(&task->sighand->siglock);
+ }
+
+ utrace_control(task, engine, UTRACE_RESUME);
+ utrace_engine_put(engine);
+}
+
/*
* ptrace a task: make the debugger its new parent and
* move it to the ptrace list.
@@ -112,30 +131,6 @@ void __ptrace_link(struct task_struct *c
}
/*
- * Turn a tracing stop into a normal stop now, since with no tracer there
- * would be no way to wake it up with SIGCONT or SIGKILL. If there was a
- * signal sent that would resume the child, but didn't because it was in
- * TASK_TRACED, resume it now.
- * Requires that irqs be disabled.
- */
-static void ptrace_untrace(struct task_struct *child)
-{
- spin_lock(&child->sighand->siglock);
- if (task_is_traced(child)) {
- /*
- * If the group stop is completed or in progress,
- * this thread was already counted as stopped.
- */
- if (child->signal->flags & SIGNAL_STOP_STOPPED ||
- child->signal->group_stop_count)
- __set_task_state(child, TASK_STOPPED);
- else
- signal_wake_up(child, 1);
- }
- spin_unlock(&child->sighand->siglock);
-}
-
-/*
* unptrace a task: move it back to its original parent and
* remove it from the ptrace list.
*
@@ -150,8 +145,6 @@ void __ptrace_unlink(struct task_struct
list_del_init(&child->ptrace_entry);
arch_ptrace_untrace(child);
- if (task_is_traced(child))
- ptrace_untrace(child);
}
/*
@@ -590,7 +583,7 @@ static int ptrace_resume(struct task_str
}
child->exit_code = data;
- wake_up_process(child);
+ ptrace_wake_up(child);
return 0;
}
