From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juan Quintela <quintela@redhat.com>
Subject: Re: [PATCH v5 1/2] kvm: support -overcommit
 cpu-pm=on|off
Date: Mon, 25 Jun 2018 10:48:47 +0200
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References: <20180622190936.177827-1-mst@redhat.com>
	<20180622190936.177827-2-mst@redhat.com>
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Cc: Eduardo Habkost <ehabkost@redhat.com>, kvm@vger.kernel.org,
	Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>
To: "Michael S. Tsirkin" <mst@redhat.com>
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In-Reply-To: <20180622190936.177827-2-mst@redhat.com> (Michael S. Tsirkin's
	message of "Fri, 22 Jun 2018 22:09:42 +0300")
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"Michael S. Tsirkin" <mst@redhat.com> wrote:
> With this flag, kvm allows guest to control host CPU power state.  This
> increases latency for other processes using same host CPU in an
> unpredictable way, but if decreases idle entry/exit times for the
> running VCPU, so to use it QEMU needs a hint about whether host CPU is
> overcommitted, hence the flag name.
>
> Follow-up patches will expose this capability to guest
> (using mwait leaf).
>
> Based on a patch by Wanpeng Li <kernellwp@gmail.com> .
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

[...]

> diff --git a/migration/migration.c b/migration/migration.c
> index 1e99ec9b7e..e468b50c4f 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -45,6 +45,7 @@
>  #include "migration/colo.h"
>  #include "hw/boards.h"
>  #include "monitor/monitor.h"
> +#include "qemu/ptr_ring.h"
>  
>  #define MAX_THROTTLE  (32 << 20)      /* Migration transfer speed throttling */
>  

Why is this chuck needed?  I can't see a reason.


Thanks, Juan.