[PATCH 0/9] fixes for memory allocator recursions into the filesystem

[PATCH 0/9] fixes for memory allocator recursions into the filesystem

[Christoph Hellwig]

lockdep has recently start tracking if a lock is used in reclaim context
and if so warns if we do allocations without the NOFS flag inside it.

This patch series fixes the easy targers involving the i_lock by switching
various allocations to the NOFS variant, or in case of the growfs code
moving the allocation out of the lock.

We still have some more issues that involve the iolock, but I think we
can simply get rid of the iolock in the reclaim path, but I'll send that
our for a separate discussion.

Sage, this should fix the two reports you've sent a while ago.

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 1/9] xfs: avoid memory allocation under m_peraglock in growfs code

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-growfs --]
[-- Type: text/plain, Size: 1590 bytes --]

Allocate the memory for the larger m_perag array before taking the
per-AG lock as the per-AG lock can be taken under the i_lock which
can be taken from reclaim context.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_fsops.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_fsops.c	2009-07-10 13:05:24.798364926 +0200
+++ linux-2.6/fs/xfs/xfs_fsops.c	2009-07-10 13:16:00.827394975 +0200
@@ -167,17 +167,25 @@ xfs_growfs_data_private(
 	new = nb - mp->m_sb.sb_dblocks;
 	oagcount = mp->m_sb.sb_agcount;
 	if (nagcount > oagcount) {
+		void *new_perag, *old_perag;
+
 		xfs_filestream_flush(mp);
+
+		new_perag = kmem_zalloc(sizeof(xfs_perag_t) * nagcount,
+					KM_MAYFAIL);
+		if (!new_perag)
+			return XFS_ERROR(ENOMEM);
+
 		down_write(&mp->m_peraglock);
-		mp->m_perag = kmem_realloc(mp->m_perag,
-			sizeof(xfs_perag_t) * nagcount,
-			sizeof(xfs_perag_t) * oagcount,
-			KM_SLEEP);
-		memset(&mp->m_perag[oagcount], 0,
-			(nagcount - oagcount) * sizeof(xfs_perag_t));
+		memcpy(new_perag, mp->m_perag, sizeof(xfs_perag_t) * oagcount);
+		old_perag = mp->m_perag;
+		mp->m_perag = new_perag;
+
 		mp->m_flags |= XFS_MOUNT_32BITINODES;
 		nagimax = xfs_initialize_perag(mp, nagcount);
 		up_write(&mp->m_peraglock);
+
+		kmem_free(old_perag);
 	}
 	tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
 	tp->t_flags |= XFS_TRANS_RESERVE;

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 2/9] xfs: switch to NOFS allocation under i_lock in xfs_getbmap

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-getbmap --]
[-- Type: text/plain, Size: 862 bytes --]

xfs_getbmap allocates memory with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_bmap.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_bmap.c	2009-07-10 13:05:24.808364312 +0200
+++ linux-2.6/fs/xfs/xfs_bmap.c	2009-07-10 13:16:00.830363579 +0200
@@ -6009,7 +6009,7 @@ xfs_getbmap(
 	 */
 	error = ENOMEM;
 	subnex = 16;
-	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL);
+	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
 	if (!map)
 		goto out_unlock_ilock;
 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 3/9] xfs: switch to NOFS allocation under i_lock in xfs_da_state_alloc

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-da_state_alloc --]
[-- Type: text/plain, Size: 877 bytes --]

xfs_da_state_alloc is always called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into the
filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_da_btree.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_da_btree.c	2009-07-10 13:05:24.812364541 +0200
+++ linux-2.6/fs/xfs/xfs_da_btree.c	2009-07-10 13:16:00.834365485 +0200
@@ -2201,7 +2201,7 @@ kmem_zone_t *xfs_dabuf_zone;		/* dabuf z
 xfs_da_state_t *
 xfs_da_state_alloc(void)
 {
-	return kmem_zone_zalloc(xfs_da_state_zone, KM_SLEEP);
+	return kmem_zone_zalloc(xfs_da_state_zone, KM_NOFS);
 }
 
 /*

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 4/9] xfs: switch to NOFS allocation under i_lock in xfs_da_buf_make

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-xfs_da_buf_make --]
[-- Type: text/plain, Size: 974 bytes --]

i_lock is taken in the reclaim context so all allocations under it
must avoid recursions into the filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_da_btree.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_da_btree.c	2009-07-10 13:05:24.812364541 +0200
+++ linux-2.6/fs/xfs/xfs_da_btree.c	2009-07-10 13:16:00.834365485 +0200
@@ -2261,9 +2261,9 @@ xfs_da_buf_make(int nbuf, xfs_buf_t **bp
 	int		off;
 
 	if (nbuf == 1)
-		dabuf = kmem_zone_alloc(xfs_dabuf_zone, KM_SLEEP);
+		dabuf = kmem_zone_alloc(xfs_dabuf_zone, KM_NOFS);
 	else
-		dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_SLEEP);
+		dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_NOFS);
 	dabuf->dirty = 0;
 #ifdef XFS_DABUF_DEBUG
 	dabuf->ra = ra;

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 5/9] xfs: switch to NOFS allocation under i_lock in xfs_dir_cilookup_result

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-dir2 --]
[-- Type: text/plain, Size: 891 bytes --]

xfs_dir_cilookup_result is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into the
filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_dir2.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_dir2.c	2009-07-10 13:05:24.817364338 +0200
+++ linux-2.6/fs/xfs/xfs_dir2.c	2009-07-10 13:16:00.834365485 +0200
@@ -256,7 +256,7 @@ xfs_dir_cilookup_result(
 					!(args->op_flags & XFS_DA_OP_CILOOKUP))
 		return EEXIST;
 
-	args->value = kmem_alloc(len, KM_MAYFAIL);
+	args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
 	if (!args->value)
 		return ENOMEM;
 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 6/9] xfs: switch to NOFS allocation under i_lock in xfs_buf_associate_memory

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-buf --]
[-- Type: text/plain, Size: 1312 bytes --]

xfs_buf_associate_memory is used for setting up the spare buffer for the
log wrap case in xlog_sync which can happen under i_lock when called from
xfs_fsync. The i_lock mutex is taken in reclaim context so all allocations
under it must avoid recursions into the filesystem.  There are a couple
more uses of xfs_buf_associate_memory in the log recovery code that are
also affected by this, but I'd rather keep the code simple than passing on
a gfp_mask argument.  Longer term we should just stop requiring the memoery
allocation in xlog_sync by some smaller rework of the buffer layer.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/linux-2.6/xfs_buf.c
===================================================================
--- linux-2.6.orig/fs/xfs/linux-2.6/xfs_buf.c	2009-07-18 18:26:07.359681952 +0200
+++ linux-2.6/fs/xfs/linux-2.6/xfs_buf.c	2009-07-18 18:26:53.531658254 +0200
@@ -770,7 +770,7 @@ xfs_buf_associate_memory(
 	bp->b_pages = NULL;
 	bp->b_addr = mem;
 
-	rval = _xfs_buf_get_pages(bp, page_count, 0);
+	rval = _xfs_buf_get_pages(bp, page_count, XBF_DONT_BLOCK);
 	if (rval)
 		return rval;
 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 7/9] xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_set

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-buf-2 --]
[-- Type: text/plain, Size: 1042 bytes --]

xfs_attr_rmtval_set is always called with i_lock held, and i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_attr.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_attr.c	2009-07-18 18:49:20.129533080 +0200
+++ linux-2.6/fs/xfs/xfs_attr.c	2009-07-18 18:50:01.713535041 +0200
@@ -2141,8 +2141,8 @@ xfs_attr_rmtval_set(xfs_da_args_t *args)
 		dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
 		blkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
 
-		bp = xfs_buf_get_flags(mp->m_ddev_targp, dblkno,
-							blkcnt, XFS_BUF_LOCK);
+		bp = xfs_buf_get_flags(mp->m_ddev_targp, dblkno, blkcnt,
+				       XFS_BUF_LOCK | XBF_DONT_BLOCK);
 		ASSERT(bp);
 		ASSERT(!XFS_BUF_GETERROR(bp));
 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 8/9] xfs: switch to NOFS allocation under i_lock in xfs_readlink_bmap

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-buf-3 --]
[-- Type: text/plain, Size: 1057 bytes --]

xfs_readlink_bmap is called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.  

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/fs/xfs/xfs_vnodeops.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_vnodeops.c	2009-07-18 20:29:59.041657600 +0200
+++ linux-2.6/fs/xfs/xfs_vnodeops.c	2009-07-18 20:31:22.964535322 +0200
@@ -547,7 +547,9 @@ xfs_readlink_bmap(
 		d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
 		byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
 
-		bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt), 0);
+		bp = xfs_buf_read_flags(mp->m_ddev_targp, d, BTOBB(byte_cnt),
+					XBF_LOCK | XBF_MAPPED |
+					XBF_DONT_BLOCK);
 		error = XFS_BUF_GETERROR(bp);
 		if (error) {
 			xfs_ioerror_alert("xfs_readlink",

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 9/9] xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_get

[Christoph Hellwig]

[-- Attachment #1: xfs-lockdep-buf-4 --]
[-- Type: text/plain, Size: 975 bytes --]

xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.  

Reported by the new reclaim context tracing in lockdep.


Index: linux-2.6/fs/xfs/xfs_attr.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_attr.c	2009-07-18 22:34:08.947532301 +0200
+++ linux-2.6/fs/xfs/xfs_attr.c	2009-07-18 22:35:44.786660003 +0200
@@ -2010,7 +2010,9 @@ xfs_attr_rmtval_get(xfs_da_args_t *args)
 			dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
 			blkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
 			error = xfs_read_buf(mp, mp->m_ddev_targp, dblkno,
-					     blkcnt, XFS_BUF_LOCK, &bp);
+					     blkcnt,
+					     XFS_BUF_LOCK | XBF_DONT_BLOCK,
+					     &bp);
 			if (error)
 				return(error);
 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

Re: [PATCH 1/9] xfs: avoid memory allocation under m_peraglock in growfs code

[Felix Blyakher]

On Jul 18, 2009, at 5:14 PM, Christoph Hellwig wrote:

> Allocate the memory for the larger m_perag array before taking the
> per-AG lock as the per-AG lock can be taken under the i_lock which
> can be taken from reclaim context.
>
> Reported by the new reclaim context tracing in lockdep.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

For the whole series:

Reviewed-by: Felix Blyakher <felixb@sgi.com>

>
>
> Index: linux-2.6/fs/xfs/xfs_fsops.c
> ===================================================================
> --- linux-2.6.orig/fs/xfs/xfs_fsops.c	2009-07-10 13:05:24.798364926  
> +0200
> +++ linux-2.6/fs/xfs/xfs_fsops.c	2009-07-10 13:16:00.827394975 +0200
> @@ -167,17 +167,25 @@ xfs_growfs_data_private(
> 	new = nb - mp->m_sb.sb_dblocks;
> 	oagcount = mp->m_sb.sb_agcount;
> 	if (nagcount > oagcount) {
> +		void *new_perag, *old_perag;
> +
> 		xfs_filestream_flush(mp);
> +
> +		new_perag = kmem_zalloc(sizeof(xfs_perag_t) * nagcount,
> +					KM_MAYFAIL);
> +		if (!new_perag)
> +			return XFS_ERROR(ENOMEM);
> +
> 		down_write(&mp->m_peraglock);
> -		mp->m_perag = kmem_realloc(mp->m_perag,
> -			sizeof(xfs_perag_t) * nagcount,
> -			sizeof(xfs_perag_t) * oagcount,
> -			KM_SLEEP);
> -		memset(&mp->m_perag[oagcount], 0,
> -			(nagcount - oagcount) * sizeof(xfs_perag_t));
> +		memcpy(new_perag, mp->m_perag, sizeof(xfs_perag_t) * oagcount);
> +		old_perag = mp->m_perag;
> +		mp->m_perag = new_perag;
> +
> 		mp->m_flags |= XFS_MOUNT_32BITINODES;
> 		nagimax = xfs_initialize_perag(mp, nagcount);
> 		up_write(&mp->m_peraglock);
> +
> +		kmem_free(old_perag);
> 	}
> 	tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
> 	tp->t_flags |= XFS_TRANS_RESERVE;
>
> _______________________________________________
> xfs mailing list
> xfs@oss.sgi.com
> http://oss.sgi.com/mailman/listinfo/xfs

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

Re: [PATCH 0/9] fixes for memory allocator recursions into the filesystem

[Sage Weil]

Hi Christoph,

I just noticed another warning (the same as the second one I sent 
before) with your patchset applied to 2.6.30.  This is the unresolved 
iolock issue you mentioned?  Just FYI.

sage


[ 4328.303413] =================================
[ 4328.305294] [ INFO: inconsistent lock state ]
[ 4328.305294] 2.6.30 #24
[ 4328.305294] ---------------------------------
[ 4328.305294] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
[ 4328.305294] kswapd0/290 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 4328.305294]  (&(&ip->i_iolock)->mr_lock){++++?+}, at: [<ffffffff803afe7e>] xfs_ilock+0x27/0x79
[ 4328.305294] {RECLAIM_FS-ON-W} state was registered at:
[ 4328.305294]   [<ffffffff8025c43b>] mark_held_locks+0x4d/0x6b
[ 4328.305294]   [<ffffffff8025c501>] lockdep_trace_alloc+0xa8/0xc3
[ 4328.305294]   [<ffffffff80287fba>] __alloc_pages_internal+0x6d/0x457
[ 4328.305294]   [<ffffffff802a8348>] alloc_pages_current+0xbe/0xc6
[ 4328.305294]   [<ffffffff80281f85>] grab_cache_page_write_begin+0x5e/0xa2
[ 4328.305294]   [<ffffffff802d300d>] block_write_begin+0x3d/0xcf
[ 4328.305294]   [<ffffffff803cbf84>] xfs_vm_write_begin+0x25/0x27
[ 4328.305294]   [<ffffffff80282926>] generic_file_buffered_write+0x139/0x2ff
[ 4328.305294]   [<ffffffff803d207e>] xfs_write+0x4de/0x717
[ 4328.305294]   [<ffffffff803cea45>] xfs_file_aio_write+0x61/0x63
[ 4328.305294]   [<ffffffff802b0d7a>] do_sync_write+0xe7/0x12d
[ 4328.305294]   [<ffffffff802b172f>] vfs_write+0xae/0x137
[ 4328.305294]   [<ffffffff802b187c>] sys_write+0x47/0x6e
[ 4328.305294]   [<ffffffff8020bb2b>] system_call_fastpath+0x16/0x1b
[ 4328.305294]   [<ffffffffffffffff>] 0xffffffffffffffff
[ 4328.305294] irq event stamp: 8357751
[ 4328.305294] hardirqs last  enabled at (8357751): [<ffffffff8062d0ec>] _spin_unlock_irqrestore+0x3f/0x68
[ 4328.450537] hardirqs last disabled at (8357750): [<ffffffff8062d440>] _spin_lock_irqsave+0x19/0x7f
[ 4328.450537] softirqs last  enabled at (8357742): [<ffffffff80240910>] __do_softirq+0x1d9/0x1e5
[ 4328.450537] softirqs last disabled at (8357721): [<ffffffff8020ccbc>] call_softirq+0x1c/0x28
[ 4328.450537] 
[ 4328.450537] other info that might help us debug this:
[ 4328.450537] 2 locks held by kswapd0/290:
[ 4328.450537]  #0:  (shrinker_rwsem){++++..}, at: [<ffffffff8028db78>] shrink_slab+0x38/0x188
[ 4328.450537]  #1:  (iprune_mutex){+.+.-.}, at: [<ffffffff802c3f97>] shrink_icache_memory+0x4b/0x23b
[ 4328.514337] 
[ 4328.514337] stack backtrace:
[ 4328.518349] Pid: 290, comm: kswapd0 Not tainted 2.6.30 #24
[ 4328.522330] Call Trace:
[ 4328.522330]  [<ffffffff8025bea5>] print_usage_bug+0x1b2/0x1c3
[ 4328.522330]  [<ffffffff8025ca86>] ? check_usage_forwards+0x0/0x9c
[ 4328.522330]  [<ffffffff8025c1b0>] mark_lock+0x2fa/0x538
[ 4328.522330]  [<ffffffff8025db79>] __lock_acquire+0x80d/0x16a9
[ 4328.522330]  [<ffffffff8025eb0b>] lock_acquire+0xf6/0x11a
[ 4328.522330]  [<ffffffff803afe7e>] ? xfs_ilock+0x27/0x79
[ 4328.522330]  [<ffffffff80252b5d>] down_write_nested+0x46/0x7a
[ 4328.522330]  [<ffffffff803afe7e>] ? xfs_ilock+0x27/0x79
[ 4328.522330]  [<ffffffff803afe7e>] xfs_ilock+0x27/0x79
[ 4328.522330]  [<ffffffff803aff8c>] xfs_ireclaim+0x8d/0x153
[ 4328.522330]  [<ffffffff803d47c8>] xfs_reclaim_inode+0x131/0x13f
[ 4328.522330]  [<ffffffff803c6ae4>] xfs_reclaim+0x98/0xa9
[ 4328.522330]  [<ffffffff803d2e86>] xfs_fs_destroy_inode+0x37/0x57
[ 4328.522330]  [<ffffffff802c3e3f>] destroy_inode+0x3a/0x4f
[ 4328.522330]  [<ffffffff802c3f18>] dispose_list+0xc4/0xf8
[ 4328.522330]  [<ffffffff802c4151>] shrink_icache_memory+0x205/0x23b
[ 4328.522330]  [<ffffffff8028dc1f>] shrink_slab+0xdf/0x188
[ 4328.522330]  [<ffffffff8028e475>] kswapd+0x4fc/0x6b2
[ 4328.522330]  [<ffffffff80232d48>] ? finish_task_switch+0x3b/0xdc
[ 4328.522330]  [<ffffffff8028bbb4>] ? isolate_pages_global+0x0/0x208
[ 4328.522330]  [<ffffffff8024fdbc>] ? autoremove_wake_function+0x0/0x38
[ 4328.522330]  [<ffffffff8025c70c>] ? trace_hardirqs_on+0xd/0xf
[ 4328.522330]  [<ffffffff8028df79>] ? kswapd+0x0/0x6b2
[ 4328.522330]  [<ffffffff8028df79>] ? kswapd+0x0/0x6b2
[ 4328.522330]  [<ffffffff8024f97d>] kthread+0x56/0x83
[ 4328.522330]  [<ffffffff8020cbba>] child_rip+0xa/0x20
[ 4328.522330]  [<ffffffff8020c580>] ? restore_args+0x0/0x30
[ 4328.522330]  [<ffffffff8062a00f>] ? __schedule+0xf9/0x948
[ 4328.522330]  [<ffffffff8024f927>] ? kthread+0x0/0x83
[ 4328.522330]  [<ffffffff8020cbb0>] ? child_rip+0x0/0x20


On Sat, 18 Jul 2009, Christoph Hellwig wrote:

> lockdep has recently start tracking if a lock is used in reclaim context
> and if so warns if we do allocations without the NOFS flag inside it.
> 
> This patch series fixes the easy targers involving the i_lock by switching
> various allocations to the NOFS variant, or in case of the growfs code
> moving the allocation out of the lock.
> 
> We still have some more issues that involve the iolock, but I think we
> can simply get rid of the iolock in the reclaim path, but I'll send that
> our for a separate discussion.
> 
> Sage, this should fix the two reports you've sent a while ago.
> 
> 

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

Re: [PATCH 0/9] fixes for memory allocator recursions into the filesystem

[Christoph Hellwig]

On Thu, Jul 30, 2009 at 11:56:58AM -0700, Sage Weil wrote:
> Hi Christoph,
> 
> I just noticed another warning (the same as the second one I sent 
> before) with your patchset applied to 2.6.30.  This is the unresolved 
> iolock issue you mentioned?  Just FYI.

Yes, that's the iolock one.  Patch will follow soon.

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs