From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Subject: Re: [PATCH] tests/gem_userptr_blits: Race between
 object creation and multi-threaded mm ops
Date: Mon, 14 Jul 2014 14:13:22 +0100
Message-ID: <53C3D772.7090004@linux.intel.com>
References: <1405332206-6292-1-git-send-email-tvrtko.ursulin@linux.intel.com>
 <20140714103416.GB2319@nuc-i3427.alporthouse.com>
 <53C3B48A.2050306@linux.intel.com>
 <20140714130725.GC2319@nuc-i3427.alporthouse.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Content-Transfer-Encoding: 7bit
Return-path: <intel-gfx-bounces@lists.freedesktop.org>
Received: from mga02.intel.com (mga02.intel.com [134.134.136.20])
 by gabe.freedesktop.org (Postfix) with ESMTP id D55656E2DB
 for <Intel-gfx@lists.freedesktop.org>; Mon, 14 Jul 2014 06:13:24 -0700 (PDT)
In-Reply-To: <20140714130725.GC2319@nuc-i3427.alporthouse.com>
List-Unsubscribe: <http://lists.freedesktop.org/mailman/options/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <http://lists.freedesktop.org/archives/intel-gfx>
List-Post: <mailto:intel-gfx@lists.freedesktop.org>
List-Help: <mailto:intel-gfx-request@lists.freedesktop.org?subject=help>
List-Subscribe: <http://lists.freedesktop.org/mailman/listinfo/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=subscribe>
Errors-To: intel-gfx-bounces@lists.freedesktop.org
Sender: "Intel-gfx" <intel-gfx-bounces@lists.freedesktop.org>
To: Chris Wilson <chris@chris-wilson.co.uk>, Intel-gfx@lists.freedesktop.org, Tvrtko Ursulin <tvrtko.ursulin@intel.com>
List-Id: intel-gfx@lists.freedesktop.org

On 07/14/2014 02:07 PM, Chris Wilson wrote:
>>> You don't have any cancellation points in the loop. (mmap may or may not
>>> be, it is not required to be.)
>>>
>>> But rather than use a global, just pass a pointer to a local struct.
>>
>> It doesn't need both a cancellation point and a flag. Should I just
>> add pthread_testcancel in the loop and not have any flag at all?
>
> testcancel also neatly avoids the handwavely lack of mb().

Barrier for what? But it doesn't matter, I'll re-spin with testcancel.

>>> Oh, and igt_assert. But kill the asserts in mm_stress_thread() first.
>>
>> Why remove completely? My thinking was to use assert vs igt_assert
>> to distinguish between assumptions about system behaviour, and
>> igt_assert for assertions about tested functionality.
>
> If the assert fires you make the igt test runner angry. Might as well
> report a test failure rather than break down completely.

I am not familiar with the test runner, but if it cannot handle a test 
failing in a way other than it expects it so it deserves to be angry. :) 
But OK, I'll change it.

Tvrtko