From patchwork Thu Sep 19 11:29:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qun-Wei Lin X-Patchwork-Id: 13807657 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E0F0CCE8D78 for ; Thu, 19 Sep 2024 11:31:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:CC:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oyX6ix+Ca+kuBSd2zaDcetxDLf8fGfj/eEE4RWU8lsQ=; b=ndyRmwdMCmGVZGV/iZBzNld6nM 7VrqrTh0akrkaj/cwFX+FX6D3jk7M2l/9w1n2m697L5SkwJEgEYf5c5bkgPn0V63tCcgU0BNKi4WF 7z8gGLMxf8p7TjmZkuROT5IhOo0mE5GQBn+A6nLHNAK2YMLc2tP9jqc57hMu0dtNBZaflc8lNyuOh QFW7iQT4AOlqpi3xaQifKHS3orFPDmb7nV5j8E+XgVwacqZcA6he2yjYQE63KuDxK2hNcjcPo64AR TJwK31nIjY+Rio5nx8plxalwFmp53DwdE4a0P4PEG3jorJ84lZ61WOh2w2T1IsVBgt4BEh+3vU+Zm OF6irsCA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1srFNi-0000000AALE-2hSH; Thu, 19 Sep 2024 11:31:30 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1srFMZ-0000000AA2d-2zgW; Thu, 19 Sep 2024 11:30:21 +0000 X-UUID: 89a67c3a767a11efb3adad29d29602c1-20240919 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=oyX6ix+Ca+kuBSd2zaDcetxDLf8fGfj/eEE4RWU8lsQ=; b=JpoSK834JdxhsMfYUVK1hDaZCq9YE9044w41Yle4h+LdHzSZKymPykj3vRiV6sdKKCTI6a2M9wG4FdtbtC0miLERvDSZvB+DrqjcwApRRTVJ8A19FvchOE0OFsjr7+o27ewfgwElCnbx9byDn8Bpn6g/ksHWagblqNHn+IhcXzo=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.41,REQID:1ff07fb1-1fa1-4f4e-8525-375b2f703bcd,IP:0,U RL:0,TC:0,Content:-25,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-25 X-CID-META: VersionHash:6dc6a47,CLOUDID:cef03d9e-8e9a-4ac1-b510-390a86b53c0a,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1, SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 0 X-CID-BAS: 0,_,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-UUID: 89a67c3a767a11efb3adad29d29602c1-20240919 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 961147067; Thu, 19 Sep 2024 04:30:13 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by MTKMBS09N2.mediatek.inc (172.21.101.94) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Thu, 19 Sep 2024 04:30:10 -0700 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Thu, 19 Sep 2024 19:30:10 +0800 From: Qun-Wei Lin To: Andrew Morton , Matthias Brugger , AngeloGioacchino Del Regno , Ryan Roberts , "Huang, Ying" , David Hildenbrand , Chris Li , "Matthew Wilcox (Oracle)" , Al Viro , Dan Schatzberg , Kairui Song , Barry Song , Jens Axboe CC: , , , , , Casper Li , Chinwen Chang , Andrew Yang , John Hsu , , Qun-Wei Lin Subject: [PATCH 1/2] block: add BLK_FEAT_READ_SYNCHRONOUS feature for synchronous read Date: Thu, 19 Sep 2024 19:29:51 +0800 Message-ID: <20240919112952.981-2-qun-wei.lin@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20240919112952.981-1-qun-wei.lin@mediatek.com> References: <20240919112952.981-1-qun-wei.lin@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240919_043019_786640_CD57E568 X-CRM114-Status: GOOD ( 12.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This commit introduces a new feature flag, BLK_FEAT_READ_SYNCHRONOUS, which ensures that read operations always complete in the submit context. This is useful for scenarios where synchronous read operations are required while allowing write operations to remain asynchronous. This patch is preparation for optimizing of the operation of the swap device with next patch. Signed-off-by: Qun-Wei Lin --- include/linux/blkdev.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 643c9020a35a..a697db11d91c 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -332,6 +332,9 @@ typedef unsigned int __bitwise blk_features_t; #define BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE \ ((__force blk_features_t)(1u << 15)) +/* read operations always completes in submit context */ +#define BLK_FEAT_READ_SYNCHRONOUS ((__force blk_features_t)(1u << 16)) + /* * Flags automatically inherited when stacking limits. */ @@ -1310,6 +1313,11 @@ static inline bool bdev_synchronous(struct block_device *bdev) return bdev->bd_disk->queue->limits.features & BLK_FEAT_SYNCHRONOUS; } +static inline bool bdev_read_synchronous(struct block_device *bdev) +{ + return bdev->bd_disk->queue->limits.features & BLK_FEAT_READ_SYNCHRONOUS; +} + static inline bool bdev_stable_writes(struct block_device *bdev) { struct request_queue *q = bdev_get_queue(bdev);