Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755481Ab1CVLZW (ORCPT ); Tue, 22 Mar 2011 07:25:22 -0400 Received: from ipmail07.adl2.internode.on.net ([150.101.137.131]:16735 "EHLO ipmail07.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753932Ab1CVLXf (ORCPT ); Tue, 22 Mar 2011 07:23:35 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApkEAK8jiE15LK5JgWdsb2JhbAClQxUBARYmJcQUhWQE From: Dave Chinner To: viro@ZenIV.linux.org.uk Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 2/8] fs: factor inode disposal Date: Tue, 22 Mar 2011 22:23:37 +1100 Message-Id: <1300793023-3775-3-git-send-email-david@fromorbit.com> X-Mailer: git-send-email 1.7.2.3 In-Reply-To: <1300793023-3775-1-git-send-email-david@fromorbit.com> References: <1300793023-3775-1-git-send-email-david@fromorbit.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6084 Lines: 208 From: Dave Chinner We have a couple of places that dispose of inodes. factor the disposal into evict() to isolate this code and make it simpler to peel away the inode_lock from the code. While doing this, change the logic flow in iput_final() to separate the different cases that need to be handled to make the transitions the inode goes through more obvious. Signed-off-by: Dave Chinner --- fs/inode.c | 104 +++++++++++++++++++++++------------------------------------ 1 files changed, 41 insertions(+), 63 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index bd5a237..442b55b 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -422,17 +422,6 @@ void __insert_inode_hash(struct inode *inode, unsigned long hashval) EXPORT_SYMBOL(__insert_inode_hash); /** - * __remove_inode_hash - remove an inode from the hash - * @inode: inode to unhash - * - * Remove an inode from the superblock. - */ -static void __remove_inode_hash(struct inode *inode) -{ - hlist_del_init(&inode->i_hash); -} - -/** * remove_inode_hash - remove an inode from the hash * @inode: inode to unhash * @@ -461,10 +450,31 @@ void end_writeback(struct inode *inode) } EXPORT_SYMBOL(end_writeback); +/* + * Free the inode passed in, removing it from the lists it is still connected + * to. We remove any pages still attached to the inode and wait for any IO that + * is still in progress before finally destroying the inode. + * + * An inode must already be marked I_FREEING so that we avoid the inode being + * moved back onto lists if we race with other code that manipulates the lists + * (e.g. writeback_single_inode). The caller is responsible for setting this. + * + * An inode must already be removed from the LRU list before being evicted from + * the cache. This should occur atomically with setting the I_FREEING state + * flag, so no inodes here should ever be on the LRU when being evicted. + */ static void evict(struct inode *inode) { const struct super_operations *op = inode->i_sb->s_op; + BUG_ON(!(inode->i_state & I_FREEING)); + BUG_ON(!list_empty(&inode->i_lru)); + + spin_lock(&inode_lock); + list_del_init(&inode->i_wb_list); + __inode_sb_list_del(inode); + spin_unlock(&inode_lock); + if (op->evict_inode) { op->evict_inode(inode); } else { @@ -476,6 +486,15 @@ static void evict(struct inode *inode) bd_forget(inode); if (S_ISCHR(inode->i_mode) && inode->i_cdev) cd_forget(inode); + + remove_inode_hash(inode); + + spin_lock(&inode->i_lock); + wake_up_bit(&inode->i_state, __I_NEW); + BUG_ON(inode->i_state != (I_FREEING | I_CLEAR)); + spin_unlock(&inode->i_lock); + + destroy_inode(inode); } /* @@ -494,16 +513,6 @@ static void dispose_list(struct list_head *head) list_del_init(&inode->i_lru); evict(inode); - - spin_lock(&inode_lock); - __remove_inode_hash(inode); - __inode_sb_list_del(inode); - spin_unlock(&inode_lock); - - spin_lock(&inode->i_lock); - wake_up_bit(&inode->i_state, __I_NEW); - spin_unlock(&inode->i_lock); - destroy_inode(inode); } } @@ -536,13 +545,7 @@ void evict_inodes(struct super_block *sb) if (!(inode->i_state & (I_DIRTY | I_SYNC))) inodes_stat.nr_unused--; spin_unlock(&inode->i_lock); - - /* - * Move the inode off the IO lists and LRU once I_FREEING is - * set so that it won't get moved back on there if it is dirty. - */ list_move(&inode->i_lru, &dispose); - list_del_init(&inode->i_wb_list); } spin_unlock(&inode_lock); @@ -595,13 +598,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) if (!(inode->i_state & (I_DIRTY | I_SYNC))) inodes_stat.nr_unused--; spin_unlock(&inode->i_lock); - - /* - * Move the inode off the IO lists and LRU once I_FREEING is - * set so that it won't get moved back on there if it is dirty. - */ list_move(&inode->i_lru, &dispose); - list_del_init(&inode->i_wb_list); } spin_unlock(&inode_lock); @@ -698,12 +695,7 @@ static void prune_icache(int nr_to_scan) inode->i_state |= I_FREEING; spin_unlock(&inode->i_lock); - /* - * Move the inode off the IO lists and LRU once I_FREEING is - * set so that it won't get moved back on there if it is dirty. - */ list_move(&inode->i_lru, &freeable); - list_del_init(&inode->i_wb_list); inodes_stat.nr_unused--; } if (current_is_kswapd()) @@ -1433,16 +1425,16 @@ static void iput_final(struct inode *inode) else drop = generic_drop_inode(inode); + if (!drop && (sb->s_flags & MS_ACTIVE)) { + inode->i_state |= I_REFERENCED; + if (!(inode->i_state & (I_DIRTY|I_SYNC))) + inode_lru_list_add(inode); + spin_unlock(&inode->i_lock); + spin_unlock(&inode_lock); + return; + } + if (!drop) { - if (sb->s_flags & MS_ACTIVE) { - inode->i_state |= I_REFERENCED; - if (!(inode->i_state & (I_DIRTY|I_SYNC))) { - inode_lru_list_add(inode); - } - spin_unlock(&inode->i_lock); - spin_unlock(&inode_lock); - return; - } inode->i_state |= I_WILL_FREE; spin_unlock(&inode->i_lock); spin_unlock(&inode_lock); @@ -1451,28 +1443,14 @@ static void iput_final(struct inode *inode) spin_lock(&inode->i_lock); WARN_ON(inode->i_state & I_NEW); inode->i_state &= ~I_WILL_FREE; - __remove_inode_hash(inode); } inode->i_state |= I_FREEING; - spin_unlock(&inode->i_lock); - - /* - * Move the inode off the IO lists and LRU once I_FREEING is - * set so that it won't get moved back on there if it is dirty. - */ inode_lru_list_del(inode); - list_del_init(&inode->i_wb_list); - - __inode_sb_list_del(inode); + spin_unlock(&inode->i_lock); spin_unlock(&inode_lock); + evict(inode); - remove_inode_hash(inode); - spin_lock(&inode->i_lock); - wake_up_bit(&inode->i_state, __I_NEW); - BUG_ON(inode->i_state != (I_FREEING | I_CLEAR)); - spin_unlock(&inode->i_lock); - destroy_inode(inode); } /** -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/