From patchwork Thu Oct 8 13:46:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Reichl X-Patchwork-Id: 11822999 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 2D78C139F for ; Thu, 8 Oct 2020 13:46:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA32C2184D for ; Thu, 8 Oct 2020 13:46:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="RowzO0QY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730407AbgJHNqa (ORCPT ); Thu, 8 Oct 2020 09:46:30 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:57826 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730396AbgJHNq3 (ORCPT ); Thu, 8 Oct 2020 09:46:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602164787; 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=SLQMImw6kiuZuVQrYxprdq/ahjqcY67ja6bifzPDmaE=; b=RowzO0QYqKkP7REiIwVrpoNrJFNAhPpxJPOXdhmbBLcjiKvukGzq9AYFek7SX28TBvl5l6 p+941jI6ZyNZekWRomqvRNHQNCViLO0SckTmcbsRfhFlZ9gFKUL6ZPg2XEvFtw3z3iBcvG fnoH4Dkclgh4J9sRaVqBsdAfUJhwL9g= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-502-MraF2-_nOq6lROjcd_4aLA-1; Thu, 08 Oct 2020 09:46:13 -0400 X-MC-Unique: MraF2-_nOq6lROjcd_4aLA-1 Received: by mail-wr1-f71.google.com with SMTP id v5so3929622wrr.0 for ; Thu, 08 Oct 2020 06:46:13 -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=SLQMImw6kiuZuVQrYxprdq/ahjqcY67ja6bifzPDmaE=; b=nmpI944usdWellvEG1gk0lUYvM6HxvuO4I5s4PTJ0MsdTfw1l4mczPOh+VhDFZ5JrX vQ8RivcpKololzYSJKOXFdPioYSoyxqloxFgQ9dJJoqpHbrp1zPCW/X2SraIwTQIqpuZ e9yEQ8vpsjyVpY2+7Qwp3hntbIogxZNQc/hKAwCZ6jLZcTfIQGP6OABc5VIjHGgWtbBt NyQea9CGVgmWW5Gvn981ESzXT2qHBLYFlFxi4ydhYCXIXlngOJ7mpCyUnoVnOyv/HnMg WMk0NCezVfEkLKXolm4wSHrbRvK4gVf+APnwc1+zj8MXJe3GCPAWhpWRBp+bH32pS76u j+Pg== X-Gm-Message-State: AOAM532kDZdIZZkV9aCSB5JcHUeRXyPVtcFYA5CUWwzUKSoUB4obmQsL pVG0Fj1pPfmK/xFxzQeuf8salfNRxGCnidupvtggOSTzxf5TcVNdDgTuEjkpA5Qb1xomrtBPNwg NxNSP96XIFoIIzNaFmVbn X-Received: by 2002:a1c:6856:: with SMTP id d83mr9185103wmc.71.1602164771499; Thu, 08 Oct 2020 06:46:11 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxCukgALFewv9u2puYdM13GbaxgXkhtT4ov+2JvaWn2ksSaC0VwYeqpN2O3Hd/YCkIOfpPDgA== X-Received: by 2002:a1c:6856:: with SMTP id d83mr9185074wmc.71.1602164771148; Thu, 08 Oct 2020 06:46:11 -0700 (PDT) Received: from localhost.localdomain.com ([84.19.91.81]) by smtp.gmail.com with ESMTPSA id s19sm7069465wmc.41.2020.10.08.06.46.10 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 Oct 2020 06:46:10 -0700 (PDT) From: Pavel Reichl To: linux-xfs@vger.kernel.org Subject: [PATCH v10 4/4] xfs: replace mrlock_t with rw_semaphores Date: Thu, 8 Oct 2020 15:46:05 +0200 Message-Id: <20201008134605.863269-5-preichl@redhat.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201008134605.863269-1-preichl@redhat.com> References: <20201008134605.863269-1-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 Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_btree.c | 24 ++++++++++++ fs/xfs/mrlock.h | 78 --------------------------------------- fs/xfs/xfs_inode.c | 50 +++++++++++++------------ 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, 57 insertions(+), 111 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..d1fdb180f7ae 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -2816,6 +2816,12 @@ xfs_btree_split_worker( unsigned long pflags; unsigned long new_pflags = PF_MEMALLOC_NOFS; + /* + * Update lockdep's lock ownership information to point to + * this thread as the thread that scheduled this worker is waiting + * for its completion. + */ + 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 @@ -2829,6 +2835,12 @@ xfs_btree_split_worker( args->result = __xfs_btree_split(args->cur, args->level, args->ptrp, args->key, args->curp, args->stat); + /* + * Update lockdep's lock ownership information to reflect that we will + * be transferring the ilock from this worker back to the scheduling + * thread. + */ + rwsem_release(&args->cur->bc_ino.ip->i_lock.dep_map, _THIS_IP_); complete(args->done); current_restore_flags_nested(&pflags, new_pflags); @@ -2863,8 +2875,20 @@ 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 a3baec1c5bcf..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); @@ -384,16 +385,17 @@ xfs_isilocked( struct xfs_inode *ip, uint lock_flags) { - if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) { - if (!(lock_flags & XFS_ILOCK_SHARED)) - return !!ip->i_lock.mr_writer; - return rwsem_is_locked(&ip->i_lock.mr_lock); + 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)) { - if (!(lock_flags & XFS_MMAPLOCK_SHARED)) - return !!ip->i_mmaplock.mr_writer; - return rwsem_is_locked(&ip->i_mmaplock.mr_lock); + 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)); } if (lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) { 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); } /*