From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:50074)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1YO4LE-00011u-1Q
	for qemu-devel@nongnu.org; Wed, 18 Feb 2015 08:07:03 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1YO4L9-0007MV-1n
	for qemu-devel@nongnu.org; Wed, 18 Feb 2015 08:06:59 -0500
Received: from mail-we0-f173.google.com ([74.125.82.173]:41814)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1YO4L8-0007MP-Q7
	for qemu-devel@nongnu.org; Wed, 18 Feb 2015 08:06:54 -0500
Received: by wevm14 with SMTP id m14so1013139wev.8
	for <qemu-devel@nongnu.org>; Wed, 18 Feb 2015 05:06:54 -0800 (PST)
Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
Message-ID: <54E48E69.6080308@redhat.com>
Date: Wed, 18 Feb 2015 14:06:49 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
MIME-Version: 1.0
References: <20150218115534.4176.12578.stgit@PASHA-ISP>
	<20150218115710.4176.28907.stgit@PASHA-ISP>
In-Reply-To: <20150218115710.4176.28907.stgit@PASHA-ISP>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [RFC PATCH v9 15/23] aio: replace stack of bottom
 halves with queue
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: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>, qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, peter.crosthwaite@xilinx.com, alex.bennee@linaro.org, mark.burton@greensocs.com, real@ispras.ru, batuzovk@ispras.ru, maria.klimushenkova@ispras.ru, afaerber@suse.de, fred.konrad@greensocs.com



On 18/02/2015 12:57, Pavel Dovgalyuk wrote:
> +        QSIMPLEQ_FOREACH_SAFE(bh, &ctx->bh_queue, next, next) {
>              if (bh->deleted) {
> -                *bhp = bh->next;
> +                QSIMPLEQ_REMOVE(&ctx->bh_queue, bh, QEMUBH, next);

QSIMPLEQ_REMOVE is very inefficient, so that this loop can become
O(n^2).  You could use QTAILQ or introduce QSIMPLE_REMOVE_AFTER.

Paolo

>                  g_free(bh);
> -            } else {
> -                bhp = &bh->next;
>              }