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From: Peter Maydell <peter.maydell@linaro.org>
To: QEMU Developers <qemu-devel@nongnu.org>
Cc: Stefan Hajnoczi <stefanha@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Subject: [Qemu-devel] in a device or CPU instance init/realize, can I rely on something having the BQL or equivalent?
Date: Thu, 7 Dec 2017 16:05:50 +0000	[thread overview]
Message-ID: <CAFEAcA-auykOKQbNcoQooNGk7Vb3wt7TH7AMA689xEj22_6KcQ@mail.gmail.com> (raw)

Hi; I'm currently writing '-cpu max' support for ARM. For that I'd
like to be able to do the "probe host kernel for its supported feature
set" in the CPU object's instance-init function, but I'd like to do
it just once and cache the answer. Can I rely on something or other
having the BQL or otherwise ensuring that two threads don't run
the instance_init method in parallel (eg in a hotplug situation),
or do I need to create and use my own mutex to protect the cached
answer data?

thanks
-- PMM

             reply	other threads:[~2017-12-07 16:06 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-07 16:05 Peter Maydell [this message]
2017-12-07 16:48 ` [Qemu-devel] in a device or CPU instance init/realize, can I rely on something having the BQL or equivalent? Igor Mammedov
2017-12-07 16:53   ` Peter Maydell
2017-12-07 17:07     ` Eduardo Habkost
2017-12-07 17:13       ` Peter Maydell
2017-12-07 17:26         ` Peter Maydell
2017-12-08 13:16           ` Igor Mammedov
2017-12-08 13:19             ` Peter Maydell
2017-12-08 14:50               ` Igor Mammedov
2017-12-08 15:05                 ` Peter Maydell
2017-12-08 16:14                 ` Eduardo Habkost
2017-12-08 17:32                   ` Igor Mammedov
2017-12-08 17:58                     ` Eduardo Habkost

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