From patchwork Tue Jan 25 21:33:16 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 507081 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p0PLhj7s001834 for ; Tue, 25 Jan 2011 21:43:45 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753862Ab1AYVnm (ORCPT ); Tue, 25 Jan 2011 16:43:42 -0500 Received: from mx1.redhat.com ([209.132.183.28]:4812 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752880Ab1AYVnl (ORCPT ); Tue, 25 Jan 2011 16:43:41 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id p0PLhfW4005588 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 25 Jan 2011 16:43:41 -0500 Received: from localhost.localdomain (test1244.test.redhat.com [10.10.10.244]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p0PLhfXx012702 for ; Tue, 25 Jan 2011 16:43:41 -0500 From: Josef Bacik To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: change reserved_extents to an atomic_t Date: Tue, 25 Jan 2011 16:33:16 -0500 Message-Id: <1295991196-975-1-git-send-email-josef@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Tue, 25 Jan 2011 21:46:23 +0000 (UTC) diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index ccc991c..57c3bb2 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -136,9 +136,8 @@ struct btrfs_inode { * items we think we'll end up using, and reserved_extents is the number * of extent items we've reserved metadata for. */ - spinlock_t accounting_lock; atomic_t outstanding_extents; - int reserved_extents; + atomic_t reserved_extents; /* * ordered_data_close is set by truncate when a file that used diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 355665b..77b31f5 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3991,6 +3991,7 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv; u64 to_reserve; int nr_extents; + int reserved_extents; int ret; if (btrfs_transaction_in_commit(root->fs_info)) @@ -3998,26 +3999,24 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) num_bytes = ALIGN(num_bytes, root->sectorsize); - spin_lock(&BTRFS_I(inode)->accounting_lock); nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1; - if (nr_extents > BTRFS_I(inode)->reserved_extents) { - nr_extents -= BTRFS_I(inode)->reserved_extents; + reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents); + + if (nr_extents > reserved_extents) { + nr_extents -= reserved_extents; to_reserve = calc_trans_metadata_size(root, nr_extents); } else { nr_extents = 0; to_reserve = 0; } - spin_unlock(&BTRFS_I(inode)->accounting_lock); to_reserve += calc_csum_metadata_size(inode, num_bytes); ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1); if (ret) return ret; - spin_lock(&BTRFS_I(inode)->accounting_lock); - BTRFS_I(inode)->reserved_extents += nr_extents; + atomic_add(nr_extents, &BTRFS_I(inode)->reserved_extents); atomic_inc(&BTRFS_I(inode)->outstanding_extents); - spin_unlock(&BTRFS_I(inode)->accounting_lock); block_rsv_add_bytes(block_rsv, to_reserve, 1); @@ -4032,19 +4031,29 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes) struct btrfs_root *root = BTRFS_I(inode)->root; u64 to_free; int nr_extents; + int reserved_extents; num_bytes = ALIGN(num_bytes, root->sectorsize); atomic_dec(&BTRFS_I(inode)->outstanding_extents); - spin_lock(&BTRFS_I(inode)->accounting_lock); - nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents); - if (nr_extents < BTRFS_I(inode)->reserved_extents) { - nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents; - BTRFS_I(inode)->reserved_extents -= nr_extents; - } else { - nr_extents = 0; - } - spin_unlock(&BTRFS_I(inode)->accounting_lock); + reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents); + do { + int old, new; + + nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents); + if (nr_extents >= reserved_extents) { + nr_extents = 0; + break; + } + old = reserved_extents; + nr_extents = reserved_extents - nr_extents; + new = reserved_extents - nr_extents; + old = atomic_cmpxchg(&BTRFS_I(inode)->reserved_extents, + reserved_extents, new); + if (likely(old == reserved_extents)) + break; + reserved_extents = old; + } while (1); to_free = calc_csum_metadata_size(inode, num_bytes); if (nr_extents > 0) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index e353da5..a744a4e 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -6495,9 +6495,8 @@ struct inode *btrfs_alloc_inode(struct super_block *sb) ei->index_cnt = (u64)-1; ei->last_unlink_trans = 0; - spin_lock_init(&ei->accounting_lock); atomic_set(&ei->outstanding_extents, 0); - ei->reserved_extents = 0; + atomic_set(&ei->reserved_extents, 0); ei->ordered_data_close = 0; ei->orphan_meta_reserved = 0; @@ -6533,7 +6532,7 @@ void btrfs_destroy_inode(struct inode *inode) WARN_ON(!list_empty(&inode->i_dentry)); WARN_ON(inode->i_data.nrpages); WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents)); - WARN_ON(BTRFS_I(inode)->reserved_extents); + WARN_ON(atomic_read(&BTRFS_I(inode)->reserved_extents)); /* * This can happen where we create an inode, but somebody else also