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Date:   Thu, 28 Sep 2023 13:24:48 +0200
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Subject: Re: [PATCH v7 4/5] drm/drm_file: Add DRM obj's RSS reporting function
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To:     =?UTF-8?Q?Adri=c3=a1n_Larumbe?= <adrian.larumbe@collabora.com>,
        maarten.lankhorst@linux.intel.com, mripard@kernel.org,
        tzimmermann@suse.de, airlied@gmail.com, daniel@ffwll.ch,
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        dmitry.baryshkov@linaro.org, sean@poorly.run,
        marijn.suijten@somainline.org, robh@kernel.org,
        steven.price@arm.com
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org,
        healych@amazon.com, kernel@collabora.com,
        tvrtko.ursulin@linux.intel.com, boris.brezillon@collabora.com
References: <20230927213133.1651169-1-adrian.larumbe@collabora.com>
 <20230927213133.1651169-5-adrian.larumbe@collabora.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20230927213133.1651169-5-adrian.larumbe@collabora.com>
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Il 27/09/23 23:29, Adrián Larumbe ha scritto:
> Some BO's might be mapped onto physical memory chunkwise and on demand,
> like Panfrost's tiler heap. In this case, even though the
> drm_gem_shmem_object page array might already be allocated, only a very
> small fraction of the BO is currently backed by system memory, but
> drm_show_memory_stats will then proceed to add its entire virtual size to
> the file's total resident size regardless.
> 
> This led to very unrealistic RSS sizes being reckoned for Panfrost, where
> said tiler heap buffer is initially allocated with a virtual size of 128
> MiB, but only a small part of it will eventually be backed by system memory
> after successive GPU page faults.
> 
> Provide a new DRM object generic function that would allow drivers to
> return a more accurate RSS and purgeable sizes for their BOs.
> 
> Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
> Reviewed-by: Steven Price <steven.price@arm.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>