From: lm@mcvoy.com (Larry McVoy)
Subject: [TUHS] signals and blocked in I/O
Date: Fri, 1 Dec 2017 08:18:10 -0800 [thread overview]
Message-ID: <20171201161810.GM3924@mcvoy.com> (raw)
In-Reply-To: <CAC20D2NcnW1YHdd5+3Y8yQqghGeLMvy8urDV7R5GevcLpizLew@mail.gmail.com>
On Fri, Dec 01, 2017 at 11:11:56AM -0500, Clem Cole wrote:
> It's hard because if I/O (like DMA) is in progress, what are the proper
> semantics to exit/roll back? When do you stop the transfer and what
> happens. When doing direct to/from disk (like a in a real-time system),
> this can get tricky.
So at first blush, what it seems like is you need a barrier to starting more
DMA's. You take the signal, the signal changes state to say to the I/O
system "finish what you are doing but then no more".
Or what you do is kill the process, tear down all of the pages except those
that are locked for I/O, leave those in the process and wait for the I/O to
get done. That might be simpler.
next prev parent reply other threads:[~2017-12-01 16:18 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-01 15:44 Larry McVoy
2017-12-01 15:53 ` Dan Cross
2017-12-01 16:11 ` Clem Cole
2017-12-01 16:18 ` Larry McVoy [this message]
2017-12-01 16:33 ` Warner Losh
2017-12-01 17:26 ` Larry McVoy
2017-12-01 19:10 ` Chris Torek
2017-12-01 23:21 ` Dave Horsfall
2017-12-01 21:33 ` Bakul Shah
2017-12-01 22:38 ` Larry McVoy
2017-12-01 23:03 ` Ralph Corderoy
2017-12-01 23:09 ` Larry McVoy
2017-12-01 23:42 ` Bakul Shah
2017-12-02 0:48 ` Larry McVoy
2017-12-02 1:40 ` Bakul Shah
2017-12-03 13:50 ` Ralph Corderoy
2017-12-04 16:36 ` arnold
2017-12-04 16:58 ` Arthur Krewat
2017-12-04 17:19 ` Warner Losh
2017-12-05 2:12 ` Bakul Shah
2017-12-04 22:07 ` Dave Horsfall
2017-12-04 22:54 ` Ron Natalie
2017-12-04 22:56 ` Warner Losh
2017-12-05 0:49 ` Dave Horsfall
2017-12-05 0:58 ` Arthur Krewat
2017-12-05 2:15 ` Dave Horsfall
2017-12-05 2:54 ` Clem cole
2017-12-02 14:59 ` Theodore Ts'o
2017-12-01 16:01 ` Dave Horsfall
2017-12-01 16:24 ` Warner Losh
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