From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:55193)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lprosek@redhat.com>) id 1aTXoG-0003m1-4Z
	for qemu-devel@nongnu.org; Wed, 10 Feb 2016 11:40:09 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <lprosek@redhat.com>) id 1aTXoC-0005WF-VQ
	for qemu-devel@nongnu.org; Wed, 10 Feb 2016 11:40:08 -0500
Received: from mx5-phx2.redhat.com ([209.132.183.37]:56251)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lprosek@redhat.com>) id 1aTXoC-0005WA-Nj
	for qemu-devel@nongnu.org; Wed, 10 Feb 2016 11:40:04 -0500
Date: Wed, 10 Feb 2016 11:40:03 -0500 (EST)
From: Ladi Prosek <lprosek@redhat.com>
Message-ID: <51909770.35566233.1455122403597.JavaMail.zimbra@redhat.com>
In-Reply-To: <56BB641F.3020104@redhat.com>
References: <1455119605-31261-1-git-send-email-lprosek@redhat.com>
	<1455119605-31261-5-git-send-email-lprosek@redhat.com>
	<56BB641F.3020104@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH v2 4/4] rng: add request queue support
	to	rng-random
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: amit shah <amit.shah@redhat.com>, pagupta@redhat.com, qemu-devel@nongnu.org

> 
> 
> On 10/02/2016 16:53, Ladi Prosek wrote:
> > +        req->size = size;
> > +        req->receive_entropy = receive_entropy;
> > +        req->opaque = opaque;
> > +        req->data = g_malloc(req->size);
> > +
> > +        k->request_entropy(s, req);
> > +
> > +        s->requests = g_slist_append(s->requests, req);
> >      }
> 
> g_slist_append has to traverse the entire list to find the place to add
> the node.  You probably are better off using QSIMPLEQ (which is an
> intrusive list unlike GSList).

This is what rng-egd does today and I would argue that since the expected
length of the list is very small - it's going to be longer than 1 only
very rarely - a simple lightweight data structure is a better choice than
trying to be O(1) in the worst case.

I'll be happy to switch to QSIMPLEQ if you want though. Your call.

Thanks!
Ladi
 
> Thanks,
> 
> Paolo
> 
>