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From: Fam Zheng <famz@redhat.com>
To: qemu-devel@nongnu.org
Cc: pbonzini@redhat.com, stefanha@redhat.com
Subject: [Qemu-devel] AioContext of block jobs
Date: Wed, 25 Mar 2015 16:31:39 +0800	[thread overview]
Message-ID: <20150325083139.GB14724@ad.nay.redhat.com> (raw)

I was looking at block jobs' AioContext and realized that the block job
coroutines are actually started in main loop.

I'm confused because 5a7e7a0bad17c96e03f55ed7019e2d7545e21a96 and friends in
the series [1] seem to move the coroutines to the BDS's iothreads, but it
didn't do that.

(Although after the first block_job_yield or sleep, the coroutines ARE resumed
in the right AioContext.)

Why is it safe to start the jobs from the main thread where QMP command is
handled? I see no guarantee that the jobs won't access BDS before first yield
but after releasing the AioContext.

Is this a bug?

[1]: http://lists.gnu.org/archive/html/qemu-devel/2014-10/msg02191.html

Thanks,
Fam

             reply	other threads:[~2015-03-25  8:31 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-25  8:31 Fam Zheng [this message]
2015-03-25 11:25 ` [Qemu-devel] AioContext of block jobs Paolo Bonzini
2015-03-25 12:06   ` Fam Zheng
2015-03-25 13:31 ` Stefan Hajnoczi
2015-03-26  3:45   ` Fam Zheng

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