2007-11-20 15:22:27

by Oleg Nesterov

[permalink] [raw]
Subject: [PATCH -mm 2/2] kill my_ptrace_child()

Now that my_ptrace_child() is trivial we can use the "p->ptrace & PT_PTRACED"
inline and simplify the corresponding logic in do_wait: we can't find the child
in TASK_TRACED state without PT_PTRACED flag set, ptrace_untrace() either sets
TASK_STOPPED or wakes up the tracee.

Signed-off-by: Oleg Nesterov <[email protected]>

--- PT/kernel/exit.c~2_my_ptrace_child 2007-11-20 17:21:52.000000000 +0300
+++ PT/kernel/exit.c 2007-11-20 17:54:07.000000000 +0300
@@ -1510,12 +1510,6 @@ static int wait_task_continued(struct ta
return retval;
}

-
-static inline int my_ptrace_child(struct task_struct *p)
-{
- return p->ptrace & PT_PTRACED;
-}
-
static long do_wait(pid_t pid, int options, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
@@ -1554,22 +1548,11 @@ repeat:
/*
* It's stopped now, so it might later
* continue, exit, or stop again.
- *
- * When we hit the race with PTRACE_ATTACH, we
- * will not report this child. But the race
- * means it has not yet been moved to our
- * ptrace_children list, so we need to set the
- * flag here to avoid a spurious ECHILD when
- * the race happens with the only child.
*/
flag = 1;
-
- if (!my_ptrace_child(p)) {
- if (is_task_traced(p))
- continue;
- if (!(options & WUNTRACED))
- continue;
- }
+ if (!(p->ptrace & PT_PTRACED) &&
+ !(options & WUNTRACED))
+ continue;

retval = wait_task_stopped(p, ret == 2,
(options & WNOWAIT), infop,


2007-11-20 21:11:19

by Roland McGrath

[permalink] [raw]
Subject: Re: [PATCH -mm 2/2] kill my_ptrace_child()

This looks ok to me.

Thanks,
Roland