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From: Paolo Bonzini <pbonzini@redhat.com>
To: Xiongzi Ge <gexxx132@umn.edu>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] The first function called after migration for a block device
Date: Fri, 27 Jun 2014 23:49:44 +0200	[thread overview]
Message-ID: <53ADE6F8.1070303@redhat.com> (raw)
In-Reply-To: <CACtCCo8YTsg6sgWB3YjYYk8AHokw0mLNvEMfkoa5Dg6=tokugA@mail.gmail.com>

Il 27/06/2014 21:41, Xiongzi Ge ha scritto:
>
> When I studied the code, I found in migration.c,
> bdrv_clear_incoming_migration_all();
>
> the cache of the bdrv devices will be deleted.
>
> Is this the one for the functions to be called after migration?
>
> Does the bdrv device need to be reopen or load state in block.c?
>
> I would like to find this function to add my new code.

This function is not going to do anything if your code is in "raw" 
format.  In particular, it has *nothing* to do with the guest OS's 
cache.  That cache is managed by the guest OS and, as I have already 
told you multiple times, there is *nothing* that QEMU can do about it.

All you can do is use O_DIRECT in the guest.

Paolo

  reply	other threads:[~2014-06-27 21:50 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-27 19:41 [Qemu-devel] The first function called after migration for a block device Xiongzi Ge
2014-06-27 21:49 ` Paolo Bonzini [this message]
2014-06-27 22:54   ` Xiongzi Ge
2014-06-30 10:48     ` Paolo Bonzini
2014-06-30 14:03       ` Xiongzi Ge
2014-06-30 14:35         ` Paolo Bonzini
2014-06-30 14:47           ` Xiongzi Ge
2014-06-30 15:13             ` Paolo Bonzini
2014-06-30 15:17               ` Xiongzi Ge

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