From nobody Sun Nov 24 17:45:41 2024 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C89141CBE82 for ; Mon, 4 Nov 2024 20:04:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.177 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730750655; cv=none; b=gdpzmF0fNS+eruZF28f8h1xFQIbPIDzd+G9rBeyeLk50xYFTLsKYnjJvlo7VDGnmd/XMQw/AmsIM+y1bzNVhCUmx6W81YJH1+Pl6LMuNDT1uTaUKHoX89Um5qrunO0ASdj/Rqj5RcIlVV3nXuefti3ehwtqlS36hfQRn9dT6CUk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730750655; c=relaxed/simple; bh=yu7yOiBkigc0Hizwa53zUq8IBTQvJdne6G9w2vObWbA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ZDH7mi55F2gr3UJob7HXIoVnyoA+hn4PjaC7zjh11RxQeLGVSuczTbTp13BRbHG3oZ9+2QJBlJ5v0gUCzDaX3eaHfEmg028GTeBUjXExvIaWymi9ci8Ck2U9rdCQzQV6ytTUXlFcxxO/8OMT2WbA8Wg8kjwN/+sjUw3guAG4mpE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=tsNzNLon; arc=none smtp.client-ip=91.218.175.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="tsNzNLon" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1730750649; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6+Cctltnj8jUTfRPzXWg7X11ZIlWeCkuZhPa7klvD+M=; b=tsNzNLonLnVwGYjHKHR5pndwa0CTcCHa1fkmIv1OZoDAGgf2SOAzTYcs1AW9APE7KXii7X rywSqhbS0+AEi2917D4rrYRiSnWpUHUXJlU5aNJHsE3DnmEpVI9sxJ8x3dE01Gxe7gCX2b ebJRVJE19zFB/IS3KSC1VwpJUZ+xfmQ= From: Sui Jingfeng To: Lucas Stach , Russell King , Christian Gmeiner Cc: David Airlie , Simona Vetter , etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Sui Jingfeng Subject: [etnaviv-next v2 1/3] drm/etnaviv: Drop offset in page manipulation Date: Tue, 5 Nov 2024 04:03:52 +0800 Message-Id: <20241104200354.656525-2-sui.jingfeng@linux.dev> In-Reply-To: <20241104200354.656525-1-sui.jingfeng@linux.dev> References: <20241104200354.656525-1-sui.jingfeng@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" The 'offset' data member of the 'struct scatterlist' denotes the offset into a SG entry in bytes. But under drm subsystem, there has nearly NO drivers that actually tough the 'offset' data member of SG anymore. Especially for drivers that could contact with drm/etnaviv. This means that all DMA addresses that sg_dma_address() gives us will be PAGE_SIZE aligned, in other words, sg->offset will always equal to 0. Drop those compulations about the offset of SG entries can save some extra overhead. Signed-off-by: Sui Jingfeng --- drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnavi= v/etnaviv_mmu.c index 8f33f111f9e8..ddb536d84c58 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c @@ -82,8 +82,8 @@ static int etnaviv_iommu_map(struct etnaviv_iommu_context= *context, return -EINVAL; =20 for_each_sgtable_dma_sg(sgt, sg, i) { - phys_addr_t pa =3D sg_dma_address(sg) - sg->offset; - unsigned int da_len =3D sg_dma_len(sg) + sg->offset; + phys_addr_t pa =3D sg_dma_address(sg); + unsigned int da_len =3D sg_dma_len(sg); unsigned int bytes =3D min_t(unsigned int, da_len, va_len); =20 VERB("map[%d]: %08x %pap(%x)", i, iova, &pa, bytes); --=20 2.34.1