Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <6b35b912-68e5-e722-0b5a-0f7bd06c22c2@collabora.com>
Date:   Mon, 1 Aug 2022 23:11:58 +0300
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.12.0
Subject: Re: [PATCH v3 09/15] drm/gem: Add LRU/shrinker helper
Content-Language: en-US
To:     Rob Clark <robdclark@gmail.com>
Cc:     dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        linux-arm-msm@vger.kernel.org, Rob Clark <robdclark@chromium.org>,
        Daniel Vetter <daniel@ffwll.ch>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        David Airlie <airlied@linux.ie>,
        open list <linux-kernel@vger.kernel.org>
References: <20220726175043.1027731-1-robdclark@gmail.com>
 <20220726175043.1027731-10-robdclark@gmail.com>
 <def8e47c-067e-0841-4ae4-1eb90244cd50@collabora.com>
 <CAF6AEGtV4GY6=PmQh0wrKxjxk_baRCzOo=s=Uz-uKBNEn7SBBg@mail.gmail.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
In-Reply-To: <CAF6AEGtV4GY6=PmQh0wrKxjxk_baRCzOo=s=Uz-uKBNEn7SBBg@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 8/1/22 23:00, Rob Clark wrote:
> On Mon, Aug 1, 2022 at 12:41 PM Dmitry Osipenko
> <dmitry.osipenko@collabora.com> wrote:
>>
>> On 7/26/22 20:50, Rob Clark wrote:
>>> +/**
>>> + * drm_gem_lru_remove - remove object from whatever LRU it is in
>>> + *
>>> + * If the object is currently in any LRU, remove it.
>>> + *
>>> + * @obj: The GEM object to remove from current LRU
>>> + */
>>> +void
>>> +drm_gem_lru_remove(struct drm_gem_object *obj)
>>> +{
>>> +     struct drm_gem_lru *lru = obj->lru;
>>> +
>>> +     if (!lru)
>>> +             return;
>>> +
>>> +     mutex_lock(lru->lock);
>>> +     lru_remove(obj);
>>> +     mutex_unlock(lru->lock);
>>> +}
>>> +EXPORT_SYMBOL(drm_gem_lru_remove);
>>
>> I made a preliminary port of the DRM-SHMEM shrinker on top of the the
>> latest version of dma-buf locking convention and yours LRU patches. It
>> all works good, the only thing that is missing for the DRM-SHMEM
>> shrinker is the drm_gem_lru_remove_locked().
>>
>> What about to add a locked variant of drm_gem_lru_remove()?
> 
> Sounds fine to me.. the only reason it didn't exist yet was because it
> wasn't needed yet..

There is no use for the drm_gem_lru_move_tail_locked() as well, you're
not using it in the MSM driver. Hence I thought it might be good to add
the drm_gem_lru_remove_locked(), or maybe the
drm_gem_lru_move_tail_locked() should be dropped then?

> I can respin w/ an addition of a _locked() version, or you can add it
> on top in your patchset.  Either is fine by me

The either option is fine by me too. If you'll keep the unused
drm_gem_lru_move_tail_locked(), then will be nice to add
drm_gem_lru_remove_locked().

-- 
Best regards,
Dmitry