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From: "Denis V. Lunev" <den@openvz.org>
To: Wen Congyang <wency@cn.fujitsu.com>
Cc: Amit Shah <amit.shah@redhat.com>,
	Igor Redko <redkoi@virtuozzo.com>,
	Juan Quintela <quintela@redhat.com>,
	qemu-devel@nongnu.org, Anna Melekhova <annam@virtuozzo.com>
Subject: Re: [Qemu-devel] [PATCH 1/2] migration: bitmap_set is unnecessary as bitmap_new uses g_try_malloc0
Date: Fri, 25 Sep 2015 13:05:00 +0300	[thread overview]
Message-ID: <56051C4C.1020602@openvz.org> (raw)
In-Reply-To: <560515DC.8050004@cn.fujitsu.com>

On 09/25/2015 12:37 PM, Wen Congyang wrote:
> On 09/25/2015 05:31 PM, Denis V. Lunev wrote:
>> On 09/25/2015 12:24 PM, Wen Congyang wrote:
>>> On 09/25/2015 05:09 PM, Denis V. Lunev wrote:
>>>> we can omit calling of bitmap_set in migration_bitmap_extend and
>>>> ram_save_setup just after bitmap_new, which properly zeroes memory
>>>> inside.
>>> This patch is wrong. bitmap_set() is set all bits of the memory to 1,
>>> not 0.
>>>
>> OK, then I'll replace g_try_malloc0 with g_try_malloc in the next patch to avoid
>> double memset
> No, bitmap_new() is called in many places. Some caller needs zero memory, and
> some caller doesn't need...
>

you are correct with your proposal with double allocation for the next 
patch.
With a specific function like I have did in v2 g_try_malloc0 can be
replaced.

Anyway, I am fine with your proposal, this is not a (very) big deal. 
EINPROGRESS

Den

  reply	other threads:[~2015-09-25 10:05 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-24 12:53 [Qemu-devel] [PATCH 1/1] migration: fix deadlock Denis V. Lunev
2015-09-25  1:21 ` Wen Congyang
2015-09-25  8:03   ` Denis V. Lunev
2015-09-25  8:23     ` Wen Congyang
2015-09-25  9:09       ` [Qemu-devel] [PATCH v2 0/2] " Denis V. Lunev
2015-09-25  9:09         ` [Qemu-devel] [PATCH 1/2] migration: bitmap_set is unnecessary as bitmap_new uses g_try_malloc0 Denis V. Lunev
2015-09-25  9:24           ` Wen Congyang
2015-09-25  9:31             ` Denis V. Lunev
2015-09-25  9:37               ` Wen Congyang
2015-09-25 10:05                 ` Denis V. Lunev [this message]
2015-09-25  9:09         ` [Qemu-devel] [PATCH 2/2] migration: fix deadlock Denis V. Lunev
2015-09-25  9:35           ` Wen Congyang
2015-09-25  9:46         ` [Qemu-devel] [PATCH v2 0/2] " Wen Congyang
2015-09-28 10:55           ` Igor Redko
2015-09-28 15:12             ` Igor Redko
2015-09-29  8:47             ` Dr. David Alan Gilbert
2015-09-30 14:28               ` Igor Redko
2015-09-29 15:32       ` [Qemu-devel] [PATCH 1/1] " Igor Redko

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