From: Chuck Ebbert <76306.1226@compuserve.com>
To: Nicholas Mc Guire <der.herr@hofr.at>
Cc: linux-kernel@vger.kernel.org
Subject: Re: problem with signal delivery SIGCHLD
Date: Tue, 19 Dec 2006 12:55:06 -0500 [thread overview]
Message-ID: <200612191259_MC3-1-D597-DE30@compuserve.com> (raw)
In-Reply-To: <Pine.LNX.4.60.0612181924470.2560@rtl14.hofr.at>
On Mon, 18 Dec 2006 20:05:35 +0100, Nicholas Mc Guire wrote:
> I have a phenomena that I don't quite understand. gdbserver forks and
> after setting ptrace (PTRACE_TRACEME, 0, 0, 0); it then execv
> (program, allargs); when this child process hits ptrace_stoped (breakpoint
> it does the following in kernel space:
>
> pid
> 1 559 5 1242 ptrace_stop
> 3 6 2 1242 | do_notify_parent_cldstop
> 4 3 2 1242 | | __group_send_sig_info
> 5 1 1 1242 | | | handle_stop_signal
> 7 0 0 1242 | | | sig_ignored
> 8 1 0 1242 | | __wake_up_sync
> 8 1 1 1242 | | | __wake_up_common
> 10 547 541 1242 | schedule
> 10 2 2 1242 | | profile_hit
> 13 1 1 1242 | | sched_clock
> 15 1 0 1242 | | deactivate_task
> 15 1 1 1242 | | | dequeue_task
> 19 2 2 0 | | __switch_to
> 24 574 574 0 default_idle
> So basically child signals -> delayed to next tick -> parent wakes up.
What do the first three columns represent?
Do you see __wake_up_common() calling default_wake_function()?
Can you trace through schedule() and see exactly how it decides to
run the idle task instead of the newly-woken parent? Exactly what
path does it take? (And which kernel version is this?)
--
MBTI: IXTP
next reply other threads:[~2006-12-19 18:00 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-12-19 17:55 Chuck Ebbert [this message]
-- strict thread matches above, loose matches on Subject: below --
2006-12-18 19:05 Nicholas Mc Guire
2006-12-20 7:10 ` Mike Galbraith
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