From: Helmut Eller <eller.helmut@gmail.com>
To: Pip Cet <pipcet@protonmail.com>
Cc: Eli Zaretskii <eliz@gnu.org>,
gerd.moellmann@gmail.com, yantar92@posteo.net,
emacs-devel@gnu.org
Subject: Re: MPS: a random backtrace while toying with gdb
Date: Mon, 01 Jul 2024 08:05:13 +0200 [thread overview]
Message-ID: <87le2lprza.fsf@gmail.com> (raw)
In-Reply-To: <ZeoWQ1RUoIjZvrUUJbNFxjD0xFOnP4zEdHo9bQPwxBQMrYl2-7cJvAVallUxxNyfIKm2PGGO9SUwm3YBk3YwYlzRfPMn68a6CEBOAnBX7s8=@protonmail.com> (Pip Cet's message of "Sun, 30 Jun 2024 19:25:36 +0000")
On Sun, Jun 30 2024, Pip Cet wrote:
> On Sunday, June 30th, 2024 at 18:42, Helmut Eller
>> This patch below implements the idea I was thinking about.
>
> I don't think it's sufficiently careful about modifying C structures
> from signal handlers, though. The signal can occur between any two CPU
> instructions, and that opens up (rare, but possible) race
> conditions. IIUC the consensus is you can set an "int" or "bool" to
> true, or write to a self-pipe, but that's about as much as you should
> ever do in a signal handler...
Hm, indeed that's a problem. Though, probably not as long as
enqueue_async_work is used only for SIGCHLD.
> As Eli points out, most of our signals don't have arguments, so how
> about simply having one flag per signal? Even a global signal flag
> would require us to block signals while we clear it.
Maybe the safest would be to use a pipe to implement the queue. That
would also work from different threads.
next prev parent reply other threads:[~2024-07-01 6:05 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-29 19:12 MPS: a random backtrace while toying with gdb Ihor Radchenko
2024-06-29 19:19 ` Pip Cet
2024-06-29 21:46 ` Gerd Möllmann
2024-06-30 4:55 ` Eli Zaretskii
2024-06-30 5:33 ` Gerd Möllmann
2024-06-30 6:16 ` Eli Zaretskii
2024-06-30 6:43 ` Gerd Möllmann
2024-06-30 8:52 ` Eli Zaretskii
2024-06-30 9:43 ` Gerd Möllmann
2024-06-30 10:05 ` Eli Zaretskii
2024-06-30 11:20 ` Gerd Möllmann
2024-06-30 12:16 ` Eli Zaretskii
2024-06-30 12:43 ` Gerd Möllmann
2024-06-30 9:36 ` Helmut Eller
2024-06-30 10:00 ` Eli Zaretskii
2024-06-30 10:24 ` Helmut Eller
2024-06-30 10:43 ` Eli Zaretskii
2024-06-30 18:42 ` Helmut Eller
2024-06-30 18:59 ` Gerd Möllmann
2024-06-30 19:25 ` Pip Cet
2024-06-30 19:49 ` Ihor Radchenko
2024-06-30 20:09 ` Eli Zaretskii
2024-06-30 20:32 ` Pip Cet
2024-07-01 11:07 ` Eli Zaretskii
2024-07-01 17:27 ` Pip Cet
2024-07-01 17:42 ` Ihor Radchenko
2024-07-01 18:08 ` Eli Zaretskii
2024-07-02 7:55 ` Pip Cet
2024-07-02 13:10 ` Eli Zaretskii
2024-07-02 14:24 ` Pip Cet
2024-07-02 14:57 ` Eli Zaretskii
2024-07-02 17:06 ` Pip Cet
2024-07-03 11:31 ` Pip Cet
2024-07-03 11:50 ` Eli Zaretskii
2024-07-03 14:35 ` Pip Cet
2024-07-03 15:41 ` Eli Zaretskii
2024-07-01 2:33 ` Eli Zaretskii
2024-07-01 6:05 ` Helmut Eller [this message]
2024-06-30 19:58 ` Eli Zaretskii
2024-06-30 21:08 ` Ihor Radchenko
2024-07-01 2:35 ` Eli Zaretskii
2024-07-01 11:13 ` Eli Zaretskii
2024-07-01 11:47 ` Ihor Radchenko
2024-07-01 12:33 ` Eli Zaretskii
2024-07-01 17:17 ` Ihor Radchenko
2024-07-01 17:44 ` Eli Zaretskii
2024-07-01 18:01 ` Ihor Radchenko
2024-07-01 18:16 ` Eli Zaretskii
2024-07-01 18:24 ` Ihor Radchenko
2024-07-01 18:31 ` Eli Zaretskii
2024-07-01 18:51 ` Ihor Radchenko
2024-07-01 19:05 ` Eli Zaretskii
2024-07-01 19:34 ` Gerd Möllmann
2024-07-01 20:00 ` Ihor Radchenko
2024-07-02 4:33 ` Gerd Möllmann
2024-07-02 7:05 ` Ihor Radchenko
2024-07-02 7:06 ` Gerd Möllmann
2024-07-01 18:19 ` Gerd Möllmann
2024-07-01 18:23 ` Eli Zaretskii
2024-06-30 11:07 ` Gerd Möllmann
2024-06-30 11:06 ` Gerd Möllmann
2024-06-30 11:05 ` Gerd Möllmann
2024-06-30 9:59 ` Pip Cet
2024-06-30 10:09 ` Eli Zaretskii
2024-06-30 10:16 ` Pip Cet
2024-06-30 10:34 ` Eli Zaretskii
2024-06-30 13:06 ` Pip Cet
2024-06-30 11:10 ` Gerd Möllmann
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