Re: [PATCH 4/4] fs: kill I_WILL_FREE

[Christian Stroetmann <stroetmann@ontolinux.com>]

  and one again
On the 24.10.2010 23:46, Christian Stroetmann wrote:
>  little typos
>
> On the 24.10.2010 19:40, Christoph Hellwig wrote:
>> The I_WILL_FREE is currently set for inodes that we write out during
>> umount after dropping their last reference.  It is handled equally
>> to I_FREEING in most places.  The two execptions are:
>>
>>   - writeback_single_inode skips all list manipulations for I_FREEING,
>>     but not for I_WILL_FREE.  We don't care about which list an
>>     I_WILL_FREE inode is on, because we will remove it from the list
>>     a little bit later.
>>   - __mark_inode_dirty skips I_FREEING inodes but not I_WILL_FREE
>>     inodes.  This only matters for filesystem that re-dirty the inode
>>     during writeback and then use the I_DIRTY flags inside 
>> ->evict_inode.
>>     The formers is done by XFS, but it uses it's internal state to flush
>>     the inode.  I could not find any filesystem that looks at I_DIRTY
>>     inside ->evict_inode either.
>>
>> Besides cleaning up the code removing I_WILL_FREE will allow us to
>> avoid one i_lock roundtrip once inode_lock is split and keep iput_final
>> more logic.  This includes removing the __remove_inode_hash call in
>> iput_final, given that we never drop the protection from lookups now
>> that I_FREEING is set earlier.
>>
>> Signed-off-by: Christoph Hellwig<hch@lst.de>
>>
>> Index: linux-2.6/fs/btrfs/inode.c
>> ===================================================================
>> --- linux-2.6.orig/fs/btrfs/inode.c    2010-10-24 16:30:05.000000000 
>> +0200
>> +++ linux-2.6/fs/btrfs/inode.c    2010-10-24 16:32:43.647253791 +0200
>> @@ -3862,8 +3862,7 @@ again:
>>           else if (inode->i_ino>  entry->vfs_inode.i_ino)
>>               p =&parent->rb_right;
>>           else {
>> -            WARN_ON(!(entry->vfs_inode.i_state&
>> -                  (I_WILL_FREE | I_FREEING)));
>> +            WARN_ON(!(entry->vfs_inode.i_state&  I_FREEING));
>>               rb_erase(parent,&root->inode_tree);
>>               RB_CLEAR_NODE(parent);
>>               spin_unlock(&root->inode_lock);
>> Index: linux-2.6/fs/drop_caches.c
>> ===================================================================
>> --- linux-2.6.orig/fs/drop_caches.c    2010-10-24 16:30:05.000000000 
>> +0200
>> +++ linux-2.6/fs/drop_caches.c    2010-10-24 16:32:43.647253791 +0200
>> @@ -18,7 +18,7 @@ static void drop_pagecache_sb(struct sup
>>
>>       spin_lock(&inode_lock);
>>       list_for_each_entry(inode,&sb->s_inodes, i_sb_list) {
>> -        if (inode->i_state&  (I_FREEING|I_WILL_FREE|I_NEW))
>> +        if (inode->i_state&  (I_FREEING | I_NEW))
>>               continue;
>>           if (inode->i_mapping->nrpages == 0)
>>               continue;
>> Index: linux-2.6/fs/gfs2/inode.c
>> ===================================================================
>> --- linux-2.6.orig/fs/gfs2/inode.c    2010-10-24 16:30:05.000000000 
>> +0200
>> +++ linux-2.6/fs/gfs2/inode.c    2010-10-24 16:32:43.650253651 +0200
>> @@ -84,7 +84,7 @@ static int iget_skip_test(struct inode *
>>       struct gfs2_skip_data *data = opaque;
>>
>>       if (ip->i_no_addr == data->no_addr) {
>> -        if (inode->i_state&  (I_FREEING|I_WILL_FREE)){
>> +        if (inode->i_state&  I_FREEING){
>>               data->skipped = 1;
>>               return 0;
>>           }
>> Index: linux-2.6/fs/fs-writeback.c
>> ===================================================================
>> --- linux-2.6.orig/fs/fs-writeback.c    2010-10-24 16:32:39.000000000 
>> +0200
>> +++ linux-2.6/fs/fs-writeback.c    2010-10-24 16:32:43.654254629 +0200
>> @@ -301,8 +301,7 @@ static void inode_wait_for_writeback(str
>>
>>   /*
>>    * Write out an inode's dirty pages.  Called under inode_lock.  
>> Either the
>> - * caller has ref on the inode (either via __iget or via syscall 
>> against an fd)
>> - * or the inode has I_WILL_FREE set (via generic_forget_inode)
>> + * caller has ref on the inode or the inode is beeing freed.
being
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