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From: Avi Kivity <avi@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Kevin Wolf <kwolf@redhat.com>,
	qemu-devel@nongnu.org, kvm@vger.kernel.org
Subject: Re: [Qemu-devel] [PATCH] posix-aio-compat: fix latency issues
Date: Sat, 13 Aug 2011 20:43:28 -0700	[thread overview]
Message-ID: <4E474460.2060803@redhat.com> (raw)
In-Reply-To: <4E452994.9080805@codemonkey.ws>

On 08/12/2011 06:24 AM, Anthony Liguori wrote:
> On 08/08/2011 06:37 AM, Avi Kivity wrote:
>>
>> +static void spawn_thread_bh_fn(void *opaque)
>> +{
>> +    mutex_lock(&lock);
>> +    do_spawn_thread();
>> +    mutex_unlock(&lock);
>> +}
>
> The locking here is odd.  Why not call do_spawn_thread() without the 
> lock, and acquire the lock for the section that needs to hold it?

Just the way the code evolved.  Note that aio_thread() does need to take 
the lock.  However, it is indeed cleaner to take the lock when needed 
rather than drop it when not.

>
> Otherwise, the logic seems correct to me.
>
> Kevin, could you also take a look at this patch?

Yes please.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.

      reply	other threads:[~2011-08-14  3:43 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-08 11:37 [Qemu-devel] [PATCH] posix-aio-compat: fix latency issues Avi Kivity
2011-08-08 12:34 ` Anthony Liguori
2011-08-08 12:42   ` Avi Kivity
2011-08-08 12:49 ` Frediano Ziglio
2011-08-08 12:54   ` Avi Kivity
2011-08-08 13:21     ` Frediano Ziglio
2011-08-08 13:26       ` Avi Kivity
2011-08-12 13:24 ` Anthony Liguori
2011-08-14  3:43   ` Avi Kivity [this message]

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