From patchwork Thu Mar 26 21:02:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Goldwyn Rodrigues X-Patchwork-Id: 11461173 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 4AAF7161F for ; Thu, 26 Mar 2020 21:03:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C3EA20719 for ; Thu, 26 Mar 2020 21:03:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727652AbgCZVDh (ORCPT ); Thu, 26 Mar 2020 17:03:37 -0400 Received: from mx2.suse.de ([195.135.220.15]:40378 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726034AbgCZVDh (ORCPT ); Thu, 26 Mar 2020 17:03:37 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 9ADABAE83; Thu, 26 Mar 2020 21:03:35 +0000 (UTC) From: Goldwyn Rodrigues To: linux-btrfs@vger.kernel.org Cc: Goldwyn Rodrigues , Nikolay Borisov , Johannes Thumshirn Subject: [PATCH 7/9] btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK Date: Thu, 26 Mar 2020 16:02:52 -0500 Message-Id: <20200326210254.17647-8-rgoldwyn@suse.de> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200326210254.17647-1-rgoldwyn@suse.de> References: <20200326210254.17647-1-rgoldwyn@suse.de> MIME-Version: 1.0 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 | 3 --- 2 files changed, 21 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 7bda178afa87..97ff3a38d704 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4701,10 +4701,7 @@ 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) {