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Message-ID: <3fe18a5f-081c-c5aa-7366-0a44035e5082@collabora.com>
Date:   Thu, 17 Mar 2022 02:03:27 +0300
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Subject: Re: [PATCH v2 6/8] drm/shmem-helper: Add generic memory shrinker
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To:     Steven Price <steven.price@arm.com>,
        David Airlie <airlied@linux.ie>,
        Gerd Hoffmann <kraxel@redhat.com>,
        Gurchetan Singh <gurchetansingh@chromium.org>,
        Chia-I Wu <olvaffe@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
        Daniel Almeida <daniel.almeida@collabora.com>,
        Gert Wollny <gert.wollny@collabora.com>,
        Tomeu Vizoso <tomeu.vizoso@collabora.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Rob Herring <robh@kernel.org>,
        Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Gustavo Padovan <gustavo.padovan@collabora.com>,
        Daniel Stone <daniel@fooishbar.org>,
        virtualization@lists.linux-foundation.org,
        Dmitry Osipenko <digetx@gmail.com>
References: <20220314224253.236359-1-dmitry.osipenko@collabora.com>
 <20220314224253.236359-7-dmitry.osipenko@collabora.com>
 <d9b39fc0-f8dd-9569-833d-7fe12a0dc859@arm.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
In-Reply-To: <d9b39fc0-f8dd-9569-833d-7fe12a0dc859@arm.com>
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On 3/16/22 18:04, Steven Price wrote:
> On 14/03/2022 22:42, Dmitry Osipenko wrote:
>> Introduce a common DRM SHMEM shrinker. It allows to reduce code
>> duplication among DRM drivers, it also handles complicated lockings
>> for the drivers. This is initial version of the shrinker that covers
>> basic needs of GPU drivers.
>>
>> This patch is based on a couple ideas borrowed from Rob's Clark MSM
>> shrinker and Thomas' Zimmermann variant of SHMEM shrinker.
>>
>> GPU drivers that want to use generic DRM memory shrinker must support
>> generic GEM reservations.
>>
>> Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> This looks fine to me, but one nitpick: you should update the comment in
> struct drm_gem_shmem_object:
> 
>> 	/**
>> 	 * @madv: State for madvise
>> 	 *
>> 	 * 0 is active/inuse.
>> 	 * A negative value is the object is purged.
>> 	 * Positive values are driver specific and not used by the helpers.
>> 	 */
>> 	int madv;
> This is adding a helper which cares about the positive values.

Good catch, I'll update the comment in v3.