Re: [PATCH] btrfs: use RB_ROOT to intialize rb_trees instead ofsetting rb_node to NULL

From: Eric Paris
Date: Tue Feb 23 2010 - 14:55:24 EST

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In reply to: Pallipadi, Venkatesh: "Re: [PATCH] btrfs: use RB_ROOT to intialize rb_trees instead ofsetting rb_node to NULL"
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On Tue, 2010-02-23 at 11:51 -0800, Pallipadi, Venkatesh wrote:
> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
>
> Quick grep also shows similar initializations in jffs2, ext4 and ext3.
> Let me know if you already have patch for them, otherwise I can send in
> the fix for those.

I do not, so I think it would be best if you sent in fixes for them.

-Eric

>
> Thanks,
> Venki
>
> On Tue, 2010-02-23 at 11:43 -0800, Eric Paris wrote:
> > btrfs inialize rb trees in quite a number of places by settin rb_node =
> > NULL; The problem with this is that 17d9ddc72fb8bba0d4f678 in the
> > linux-next tree adds a new field to that struct which needs to be NULL for
> > the new rbtree library code to work properly. This patch uses RB_ROOT as
> > the intializer so all of the relevant fields will be NULL'd. Without the
> > patch I get a panic like that shown below and after the patch my system
> > boots.
> >
> > [ 5.314627] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
> > [ 5.315518] last sysfs file: /sys/kernel/uevent_seqnum
> > [ 5.315518] CPU 0
> > [ 5.315518] Modules linked in: [last unloaded: scsi_wait_scan]
> > [ 5.315518]
> > [ 5.315518] Pid: 1314, comm: mount Not tainted 2.6.33-rc8-next-20100223+ #21 /KVM
> > [ 5.315518] RIP: 0010:[<ffffffff81296cc0>] [<ffffffff81296cc0>] rb_insert_color+0x20/0x120
> > [ 5.315518] RSP: 0018:ffff88003cc21a88 EFLAGS: 00010206
> > [ 5.315518] RAX: 5a5a5a5a5a5a5a5a RBX: ffffea0000d5e5b8 RCX: 0000000000000000
> > [ 5.315518] RDX: ffff88003d710080 RSI: ffff88003d710080 RDI: ffff88003d610058
> > [ 5.315518] RBP: ffff88003cc21ab8 R08: 0000000000000002 R09: 0000000000000000
> > [ 5.315518] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88003d710070
> > [ 5.315518] R13: 0000000000000010 R14: ffff88003d610058 R15: ffff88003d710080
> > [ 5.315518] FS: 00007ffe37b197e0(0000) GS:ffff880004000000(0000) knlGS:0000000000000000
> > [ 5.315518] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> > [ 5.315518] CR2: 00007ffe36d7d010 CR3: 000000003cd94000 CR4: 00000000000006f0
> > [ 5.315518] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > [ 5.315518] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > [ 5.315518] Process mount (pid: 1314, threadinfo ffff88003cc20000, task ffff88003d100000)
> > [ 5.315518] Stack:
> > [ 5.315518] ffff88003cc21ab8 ffffea0000d5e5b8 ffff88003d710070 0000000000000010
> > [ 5.315518] <0> ffff88003d7100e0 0000000000010000 ffff88003cc21b48 ffffffff812058b4
> > [ 5.315518] <0> ffff88003cc2e060 ffff88003cc20000 0000000000000010 000000503cc2dff0
> > [ 5.315518] Call Trace:
> > [ 5.315518] [<ffffffff812058b4>] alloc_extent_buffer+0x294/0x410
> > [ 5.315518] [<ffffffff811dfa28>] btrfs_find_create_tree_block+0x28/0x30
> > [ 5.315518] [<ffffffff81209cd1>] btrfs_read_sys_array+0x31/0x150
> > [ 5.315518] [<ffffffff811e429a>] open_ctree+0x109a/0x1710
> > [ 5.315518] [<ffffffff81133bc5>] ? sget+0x365/0x480
> > [ 5.315518] [<ffffffff812980af>] ? strlcpy+0x4f/0x70
> > [ 5.315518] [<ffffffff811c4f8c>] btrfs_get_sb+0x41c/0x510
> > [ 5.315518] [<ffffffff8114a846>] ? alloc_vfsmnt+0xc6/0x1a0
> > [ 5.315518] [<ffffffff81133249>] vfs_kern_mount+0x89/0x1a0
> > [ 5.315518] [<ffffffff811333ce>] do_kern_mount+0x4e/0x110
> > [ 5.315518] [<ffffffff8114cb47>] do_mount+0x547/0x800
> > [ 5.315518] [<ffffffff810fe660>] ? strndup_user+0x80/0xb0
> > [ 5.315518] [<ffffffff8114ce8a>] sys_mount+0x8a/0xd0
> > [ 5.315518] [<ffffffff8100ae02>] system_call_fastpath+0x16/0x1b
> >
> > Signed-off-by: Eric Paris <eparis@xxxxxxxxxx>
> > ---
> >
> > fs/btrfs/disk-io.c | 4 ++--
> > fs/btrfs/extent_io.c | 4 ++--
> > fs/btrfs/extent_map.c | 2 +-
> > fs/btrfs/free-space-cache.c | 4 ++--
> > fs/btrfs/ordered-data.h | 2 +-
> > fs/btrfs/ref-cache.h | 2 +-
> > fs/btrfs/relocation.c | 4 ++--
> > fs/btrfs/transaction.c | 2 +-
> > 8 files changed, 12 insertions(+), 12 deletions(-)
> >
> > diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> > index 2b59201..0427183 100644
> > --- a/fs/btrfs/disk-io.c
> > +++ b/fs/btrfs/disk-io.c
> > @@ -901,7 +901,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
> > root->highest_objectid = 0;
> > root->name = NULL;
> > root->in_sysfs = 0;
> > - root->inode_tree.rb_node = NULL;
> > + root->inode_tree = RB_ROOT;
> >
> > INIT_LIST_HEAD(&root->dirty_list);
> > INIT_LIST_HEAD(&root->orphan_list);
> > @@ -1673,7 +1673,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
> > insert_inode_hash(fs_info->btree_inode);
> >
> > spin_lock_init(&fs_info->block_group_cache_lock);
> > - fs_info->block_group_cache_tree.rb_node = NULL;
> > + fs_info->block_group_cache_tree = RB_ROOT;
> >
> > extent_io_tree_init(&fs_info->freed_extents[0],
> > fs_info->btree_inode->i_mapping, GFP_NOFS);
> > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
> > index b177ed3..7073cbb 100644
> > --- a/fs/btrfs/extent_io.c
> > +++ b/fs/btrfs/extent_io.c
> > @@ -104,8 +104,8 @@ void extent_io_exit(void)
> > void extent_io_tree_init(struct extent_io_tree *tree,
> > struct address_space *mapping, gfp_t mask)
> > {
> > - tree->state.rb_node = NULL;
> > - tree->buffer.rb_node = NULL;
> > + tree->state = RB_ROOT;
> > + tree->buffer = RB_ROOT;
> > tree->ops = NULL;
> > tree->dirty_bytes = 0;
> > spin_lock_init(&tree->lock);
> > diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
> > index 428fcac..28d87ba 100644
> > --- a/fs/btrfs/extent_map.c
> > +++ b/fs/btrfs/extent_map.c
> > @@ -35,7 +35,7 @@ void extent_map_exit(void)
> > */
> > void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask)
> > {
> > - tree->map.rb_node = NULL;
> > + tree->map = RB_ROOT;
> > rwlock_init(&tree->lock);
> > }
> >
> > diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
> > index cb2849f..dd831ed 100644
> > --- a/fs/btrfs/free-space-cache.c
> > +++ b/fs/btrfs/free-space-cache.c
> > @@ -870,7 +870,7 @@ __btrfs_return_cluster_to_free_space(
> > tree_insert_offset(&block_group->free_space_offset,
> > entry->offset, &entry->offset_index, 0);
> > }
> > - cluster->root.rb_node = NULL;
> > + cluster->root = RB_ROOT;
> >
> > out:
> > spin_unlock(&cluster->lock);
> > @@ -1355,7 +1355,7 @@ void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster)
> > {
> > spin_lock_init(&cluster->lock);
> > spin_lock_init(&cluster->refill_lock);
> > - cluster->root.rb_node = NULL;
> > + cluster->root = RB_ROOT;
> > cluster->max_size = 0;
> > cluster->points_to_bitmap = false;
> > INIT_LIST_HEAD(&cluster->block_group_list);
> > diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
> > index 1fe1282..9116c6d 100644
> > --- a/fs/btrfs/ordered-data.h
> > +++ b/fs/btrfs/ordered-data.h
> > @@ -129,7 +129,7 @@ static inline void
> > btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
> > {
> > mutex_init(&t->mutex);
> > - t->tree.rb_node = NULL;
> > + t->tree = RB_ROOT;
> > t->last = NULL;
> > }
> >
> > diff --git a/fs/btrfs/ref-cache.h b/fs/btrfs/ref-cache.h
> > index bc283ad..e2a55cb 100644
> > --- a/fs/btrfs/ref-cache.h
> > +++ b/fs/btrfs/ref-cache.h
> > @@ -52,7 +52,7 @@ static inline size_t btrfs_leaf_ref_size(int nr_extents)
> >
> > static inline void btrfs_leaf_ref_tree_init(struct btrfs_leaf_ref_tree *tree)
> > {
> > - tree->root.rb_node = NULL;
> > + tree->root = RB_ROOT;
> > INIT_LIST_HEAD(&tree->list);
> > spin_lock_init(&tree->lock);
> > }
> > diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
> > index ab7ab53..0109e56 100644
> > --- a/fs/btrfs/relocation.c
> > +++ b/fs/btrfs/relocation.c
> > @@ -170,14 +170,14 @@ struct async_merge {
> >
> > static void mapping_tree_init(struct mapping_tree *tree)
> > {
> > - tree->rb_root.rb_node = NULL;
> > + tree->rb_root = RB_ROOT;
> > spin_lock_init(&tree->lock);
> > }
> >
> > static void backref_cache_init(struct backref_cache *cache)
> > {
> > int i;
> > - cache->rb_root.rb_node = NULL;
> > + cache->rb_root = RB_ROOT;
> > for (i = 0; i < BTRFS_MAX_LEVEL; i++)
> > INIT_LIST_HEAD(&cache->pending[i]);
> > spin_lock_init(&cache->lock);
> > diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
> > index b2acc79..2a36e23 100644
> > --- a/fs/btrfs/transaction.c
> > +++ b/fs/btrfs/transaction.c
> > @@ -69,7 +69,7 @@ static noinline int join_transaction(struct btrfs_root *root)
> > cur_trans->commit_done = 0;
> > cur_trans->start_time = get_seconds();
> >
> > - cur_trans->delayed_refs.root.rb_node = NULL;
> > + cur_trans->delayed_refs.root = RB_ROOT;
> > cur_trans->delayed_refs.num_entries = 0;
> > cur_trans->delayed_refs.num_heads_ready = 0;
> > cur_trans->delayed_refs.num_heads = 0;
> >
>
>

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Next message: Rafael J. Wysocki: "Re: [PATCH 1/8] PCI PM: Add function for checking PME status of devices"
Previous message: Al Viro: "Re: linux-next requirements (Was: Re: [tip:x86/ptrace] ptrace: Addsupport for generic PTRACE_GETREGSET/PTRACE_SETREGSET)"
In reply to: Pallipadi, Venkatesh: "Re: [PATCH] btrfs: use RB_ROOT to intialize rb_trees instead ofsetting rb_node to NULL"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]