From patchwork Tue Oct 6 19:15:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Reichl X-Patchwork-Id: 11819097 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 EA8A059D for ; Tue, 6 Oct 2020 19:16:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B117D206F4 for ; Tue, 6 Oct 2020 19:16:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dCf64u6h" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727050AbgJFTQB (ORCPT ); Tue, 6 Oct 2020 15:16:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:36040 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727033AbgJFTQA (ORCPT ); Tue, 6 Oct 2020 15:16:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602011757; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LW8Nd1gmoXyRVUhU85FAeRla1hlIXdv1edHwm/LKMso=; b=dCf64u6hlKHJEHc6PsTAQTsLDnPHRNOk8QVyCm4YawRqBno/BBRP78tOs+drhkJrn7Xqwc bKG07VLgx/oErtkbI6UbiUkTCtfaczRmcltr6cc6w3U4fYRWf0J07PgnCrCZ66uSsV/Fpd 0XpfXhXHPcC/J+flyofxyapauEd09QU= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-77-QCFx9E8MM8aJeucAWR76ZA-1; Tue, 06 Oct 2020 15:15:49 -0400 X-MC-Unique: QCFx9E8MM8aJeucAWR76ZA-1 Received: by mail-wm1-f72.google.com with SMTP id z7so1479053wmi.3 for ; Tue, 06 Oct 2020 12:15:49 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=LW8Nd1gmoXyRVUhU85FAeRla1hlIXdv1edHwm/LKMso=; b=TAPUajkvVnyI0qFNuTk4QOoNg8VEAx/IpActAZij9nL/11WvoZXciHvx2zg8IzDz0l L0E/EbE457wA0WtAsweYVWAqgy5fGefiN8ncC/qfNxuxfLPch1GyiGX2dVVy1qHGifRq 0oJUNJCwy4YPbcv5LviitfSMMbwMgOuD1V60MLj1MdixNwmNg35wESjOGfo8NNUMK1j4 8UguYM2D0GQEQXv7SPUuqJ0OOu0VFofmxGCB6zp4Su/+V0QglEzAEEimb7SSC+5XPH21 4gsTJQUnigWH+DYTsyOjwfNx9sJZ1M5R3PUNdBkgWZhzd20npSkffStVyBLoSTC2Lamr f9Ag== X-Gm-Message-State: AOAM533U0FSZpgna8Tt2+f3sjXZjDg0MtbS3y66sNmrEH48kDKOLywID 7QLuVw2x5Ag31BYFYg8c4SrsB9AnQJFKbsGYdX3nt6qMa5Cil3ZJ1XEH3Ch4cB8W3PPlJmqcr14 Os9D/QgY8b2T3ZFjn6kBG X-Received: by 2002:a1c:c28a:: with SMTP id s132mr6708920wmf.13.1602011747954; Tue, 06 Oct 2020 12:15:47 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyLsKH5bQ/erpgc3dQUpdZco58PoZdXjLfzhhpiLMcRx6zoWQ78ZRqOtNjcEc1/cFtNA41aJQ== X-Received: by 2002:a1c:c28a:: with SMTP id s132mr6708910wmf.13.1602011747641; Tue, 06 Oct 2020 12:15:47 -0700 (PDT) Received: from localhost.localdomain.com ([84.19.91.81]) by smtp.gmail.com with ESMTPSA id v17sm5317074wrc.23.2020.10.06.12.15.46 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 06 Oct 2020 12:15:46 -0700 (PDT) From: Pavel Reichl To: linux-xfs@vger.kernel.org Subject: [PATCH v9 4/4] xfs: replace mrlock_t with rw_semaphores Date: Tue, 6 Oct 2020 21:15:41 +0200 Message-Id: <20201006191541.115364-5-preichl@redhat.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201006191541.115364-1-preichl@redhat.com> References: <20201006191541.115364-1-preichl@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Remove mrlock_t as it does not provide any extra value over rw_semaphores. Make i_lock and i_mmaplock native rw_semaphores and replace mr*() functions with native rwsem calls. Release the lock in xfs_btree_split() just before the work-queue executing xfs_btree_split_worker() is scheduled and make xfs_btree_split_worker() to acquire the lock as a first thing and release it just before returning from the function. This it done so the ownership of the lock is transfered between kernel threads and thus lockdep won't complain about lock being held by a different kernel thread. Signed-off-by: Pavel Reichl --- fs/xfs/libxfs/xfs_btree.c | 14 +++++++ fs/xfs/mrlock.h | 78 --------------------------------------- fs/xfs/xfs_inode.c | 36 ++++++++++-------- fs/xfs/xfs_inode.h | 4 +- fs/xfs/xfs_iops.c | 4 +- fs/xfs/xfs_linux.h | 2 +- fs/xfs/xfs_super.c | 6 +-- 7 files changed, 41 insertions(+), 103 deletions(-) delete mode 100644 fs/xfs/mrlock.h diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index 2d25bab68764..1d1bb8423688 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -2816,6 +2816,7 @@ xfs_btree_split_worker( unsigned long pflags; unsigned long new_pflags = PF_MEMALLOC_NOFS; + rwsem_acquire(&args->cur->bc_ino.ip->i_lock.dep_map, 0, 0, _RET_IP_); /* * we are in a transaction context here, but may also be doing work * in kswapd context, and hence we may need to inherit that state @@ -2832,6 +2833,7 @@ xfs_btree_split_worker( complete(args->done); current_restore_flags_nested(&pflags, new_pflags); + rwsem_release(&args->cur->bc_ino.ip->i_lock.dep_map, _THIS_IP_); } /* @@ -2863,8 +2865,20 @@ xfs_btree_split( args.done = &done; args.kswapd = current_is_kswapd(); INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker); + /* + * Update lockdep's ownership information to reflect that we + * will be transferring the ilock from this thread to the + * worker. + */ + rwsem_release(&cur->bc_ino.ip->i_lock.dep_map, _THIS_IP_); queue_work(xfs_alloc_wq, &args.work); wait_for_completion(&done); + /* + * Update lockdep's lock ownership information to point to + * this thread as the lock owner now that the worker item is + * done. + */ + rwsem_acquire(&cur->bc_ino.ip->i_lock.dep_map, 0, 0, _RET_IP_); destroy_work_on_stack(&args.work); return args.result; } diff --git a/fs/xfs/mrlock.h b/fs/xfs/mrlock.h deleted file mode 100644 index 79155eec341b..000000000000 --- a/fs/xfs/mrlock.h +++ /dev/null @@ -1,78 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright (c) 2000-2006 Silicon Graphics, Inc. - * All Rights Reserved. - */ -#ifndef __XFS_SUPPORT_MRLOCK_H__ -#define __XFS_SUPPORT_MRLOCK_H__ - -#include - -typedef struct { - struct rw_semaphore mr_lock; -#if defined(DEBUG) || defined(XFS_WARN) - int mr_writer; -#endif -} mrlock_t; - -#if defined(DEBUG) || defined(XFS_WARN) -#define mrinit(mrp, name) \ - do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0) -#else -#define mrinit(mrp, name) \ - do { init_rwsem(&(mrp)->mr_lock); } while (0) -#endif - -#define mrlock_init(mrp, t,n,s) mrinit(mrp, n) -#define mrfree(mrp) do { } while (0) - -static inline void mraccess_nested(mrlock_t *mrp, int subclass) -{ - down_read_nested(&mrp->mr_lock, subclass); -} - -static inline void mrupdate_nested(mrlock_t *mrp, int subclass) -{ - down_write_nested(&mrp->mr_lock, subclass); -#if defined(DEBUG) || defined(XFS_WARN) - mrp->mr_writer = 1; -#endif -} - -static inline int mrtryaccess(mrlock_t *mrp) -{ - return down_read_trylock(&mrp->mr_lock); -} - -static inline int mrtryupdate(mrlock_t *mrp) -{ - if (!down_write_trylock(&mrp->mr_lock)) - return 0; -#if defined(DEBUG) || defined(XFS_WARN) - mrp->mr_writer = 1; -#endif - return 1; -} - -static inline void mrunlock_excl(mrlock_t *mrp) -{ -#if defined(DEBUG) || defined(XFS_WARN) - mrp->mr_writer = 0; -#endif - up_write(&mrp->mr_lock); -} - -static inline void mrunlock_shared(mrlock_t *mrp) -{ - up_read(&mrp->mr_lock); -} - -static inline void mrdemote(mrlock_t *mrp) -{ -#if defined(DEBUG) || defined(XFS_WARN) - mrp->mr_writer = 0; -#endif - downgrade_write(&mrp->mr_lock); -} - -#endif /* __XFS_SUPPORT_MRLOCK_H__ */ diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 035925d406d5..213a4a947854 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -191,14 +191,15 @@ xfs_ilock( } if (lock_flags & XFS_MMAPLOCK_EXCL) - mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags)); + down_write_nested(&ip->i_mmaplock, + XFS_MMAPLOCK_DEP(lock_flags)); else if (lock_flags & XFS_MMAPLOCK_SHARED) - mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags)); + down_read_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags)); if (lock_flags & XFS_ILOCK_EXCL) - mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); + down_write_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); else if (lock_flags & XFS_ILOCK_SHARED) - mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); + down_read_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); } /* @@ -242,27 +243,27 @@ xfs_ilock_nowait( } if (lock_flags & XFS_MMAPLOCK_EXCL) { - if (!mrtryupdate(&ip->i_mmaplock)) + if (!down_write_trylock(&ip->i_mmaplock)) goto out_undo_iolock; } else if (lock_flags & XFS_MMAPLOCK_SHARED) { - if (!mrtryaccess(&ip->i_mmaplock)) + if (!down_read_trylock(&ip->i_mmaplock)) goto out_undo_iolock; } if (lock_flags & XFS_ILOCK_EXCL) { - if (!mrtryupdate(&ip->i_lock)) + if (!down_write_trylock(&ip->i_lock)) goto out_undo_mmaplock; } else if (lock_flags & XFS_ILOCK_SHARED) { - if (!mrtryaccess(&ip->i_lock)) + if (!down_read_trylock(&ip->i_lock)) goto out_undo_mmaplock; } return 1; out_undo_mmaplock: if (lock_flags & XFS_MMAPLOCK_EXCL) - mrunlock_excl(&ip->i_mmaplock); + up_write(&ip->i_mmaplock); else if (lock_flags & XFS_MMAPLOCK_SHARED) - mrunlock_shared(&ip->i_mmaplock); + up_read(&ip->i_mmaplock); out_undo_iolock: if (lock_flags & XFS_IOLOCK_EXCL) up_write(&VFS_I(ip)->i_rwsem); @@ -309,14 +310,14 @@ xfs_iunlock( up_read(&VFS_I(ip)->i_rwsem); if (lock_flags & XFS_MMAPLOCK_EXCL) - mrunlock_excl(&ip->i_mmaplock); + up_write(&ip->i_mmaplock); else if (lock_flags & XFS_MMAPLOCK_SHARED) - mrunlock_shared(&ip->i_mmaplock); + up_read(&ip->i_mmaplock); if (lock_flags & XFS_ILOCK_EXCL) - mrunlock_excl(&ip->i_lock); + up_write(&ip->i_lock); else if (lock_flags & XFS_ILOCK_SHARED) - mrunlock_shared(&ip->i_lock); + up_read(&ip->i_lock); trace_xfs_iunlock(ip, lock_flags, _RET_IP_); } @@ -335,9 +336,9 @@ xfs_ilock_demote( ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); if (lock_flags & XFS_ILOCK_EXCL) - mrdemote(&ip->i_lock); + downgrade_write(&ip->i_lock); if (lock_flags & XFS_MMAPLOCK_EXCL) - mrdemote(&ip->i_mmaplock); + downgrade_write(&ip->i_mmaplock); if (lock_flags & XFS_IOLOCK_EXCL) downgrade_write(&VFS_I(ip)->i_rwsem); @@ -385,11 +386,14 @@ xfs_isilocked( uint lock_flags) { if (lock_flags & (XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)) { + ASSERT(!(lock_flags & ~(XFS_ILOCK_EXCL | XFS_ILOCK_SHARED))); return __xfs_rwsem_islocked(&ip->i_lock, (lock_flags >> XFS_ILOCK_FLAG_SHIFT)); } if (lock_flags & (XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED)) { + ASSERT(!(lock_flags & + ~(XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED))); return __xfs_rwsem_islocked(&ip->i_mmaplock, (lock_flags >> XFS_MMAPLOCK_FLAG_SHIFT)); } diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h index 77d5655191ab..02c98ecfe4c5 100644 --- a/fs/xfs/xfs_inode.h +++ b/fs/xfs/xfs_inode.h @@ -39,8 +39,8 @@ typedef struct xfs_inode { /* Transaction and locking information. */ struct xfs_inode_log_item *i_itemp; /* logging information */ - mrlock_t i_lock; /* inode lock */ - mrlock_t i_mmaplock; /* inode mmap IO lock */ + struct rw_semaphore i_lock; /* inode lock */ + struct rw_semaphore i_mmaplock; /* inode mmap IO lock */ atomic_t i_pincount; /* inode pin count */ /* diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index 80a13c8561d8..66cca3e599c7 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -1336,9 +1336,9 @@ xfs_setup_inode( */ lockdep_set_class(&inode->i_rwsem, &inode->i_sb->s_type->i_mutex_dir_key); - lockdep_set_class(&ip->i_lock.mr_lock, &xfs_dir_ilock_class); + lockdep_set_class(&ip->i_lock, &xfs_dir_ilock_class); } else { - lockdep_set_class(&ip->i_lock.mr_lock, &xfs_nondir_ilock_class); + lockdep_set_class(&ip->i_lock, &xfs_nondir_ilock_class); } /* diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index ab737fed7b12..ba37217f86d2 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -22,7 +22,6 @@ typedef __u32 xfs_nlink_t; #include "xfs_types.h" #include "kmem.h" -#include "mrlock.h" #include #include @@ -61,6 +60,7 @@ typedef __u32 xfs_nlink_t; #include #include #include +#include #include #include diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 71ac6c1cdc36..00be9cfa29fa 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -708,10 +708,8 @@ xfs_fs_inode_init_once( atomic_set(&ip->i_pincount, 0); spin_lock_init(&ip->i_flags_lock); - mrlock_init(&ip->i_mmaplock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER, - "xfsino", ip->i_ino); - mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER, - "xfsino", ip->i_ino); + init_rwsem(&ip->i_mmaplock); + init_rwsem(&ip->i_lock); } /*