From patchwork Thu Dec 12 00:30:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Goldwyn Rodrigues X-Patchwork-Id: 11286653 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 92B41112B for ; Thu, 12 Dec 2019 00:31:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 72A9221655 for ; Thu, 12 Dec 2019 00:31:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727453AbfLLAbJ (ORCPT ); Wed, 11 Dec 2019 19:31:09 -0500 Received: from mx2.suse.de ([195.135.220.15]:42316 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727359AbfLLAbI (ORCPT ); Wed, 11 Dec 2019 19:31:08 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id CFF9DACF2; Thu, 12 Dec 2019 00:31:06 +0000 (UTC) From: Goldwyn Rodrigues To: linux-btrfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, hch@infradead.org, darrick.wong@oracle.com, fdmanana@kernel.org, dsterba@suse.cz, jthumshirn@suse.de, nborisov@suse.com, Goldwyn Rodrigues Subject: [PATCH 8/8] btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK Date: Wed, 11 Dec 2019 18:30:43 -0600 Message-Id: <20191212003043.31093-9-rgoldwyn@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20191212003043.31093-1-rgoldwyn@suse.de> References: <20191212003043.31093-1-rgoldwyn@suse.de> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Goldwyn Rodrigues Since we now perform direct reads using i_rwsem, we can remove this inode flag used to co-ordinate unlocked reads. The truncate call takes i_rwsem. This means it is correctly synchronized with concurrent direct reads. Signed-off-by: Goldwyn Rodrigues Reviewed-by: Nikolay Borisov Reviewed-by: Johannes Thumshirn --- fs/btrfs/btrfs_inode.h | 18 ------------------ fs/btrfs/inode.c | 5 ----- 2 files changed, 23 deletions(-) diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 4e12a477d32e..cd8f378ed8e7 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -27,7 +27,6 @@ enum { BTRFS_INODE_NEEDS_FULL_SYNC, BTRFS_INODE_COPY_EVERYTHING, BTRFS_INODE_IN_DELALLOC_LIST, - BTRFS_INODE_READDIO_NEED_LOCK, BTRFS_INODE_HAS_PROPS, BTRFS_INODE_SNAPSHOT_FLUSH, }; @@ -317,23 +316,6 @@ struct btrfs_dio_private { blk_status_t); }; -/* - * Disable DIO read nolock optimization, so new dio readers will be forced - * to grab i_mutex. It is used to avoid the endless truncate due to - * nonlocked dio read. - */ -static inline void btrfs_inode_block_unlocked_dio(struct btrfs_inode *inode) -{ - set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags); - smp_mb(); -} - -static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode) -{ - smp_mb__before_atomic(); - clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags); -} - /* Array of bytes with variable length, hexadecimal format 0x1234 */ #define CSUM_FMT "0x%*phN" #define CSUM_FMT_VALUE(size, bytes) size, bytes diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c5c809ab84cf..501e2a8f5b93 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5273,11 +5273,6 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr) truncate_setsize(inode, newsize); - /* Disable nonlocked read DIO to avoid the endless truncate */ - btrfs_inode_block_unlocked_dio(BTRFS_I(inode)); - inode_dio_wait(inode); - btrfs_inode_resume_unlocked_dio(BTRFS_I(inode)); - ret = btrfs_truncate(inode, newsize == oldsize); if (ret && inode->i_nlink) { int err;