diff mbox

[RESEND] btrfs: Fix slab accounting flags

Message ID 1468185141-20253-1-git-send-email-n.borisov.lkml@gmail.com (mailing list archive)
State Accepted
Headers show

Commit Message

Nikolay Borisov July 10, 2016, 9:12 p.m. UTC 
BTRFS is using a variety of slab caches to satisfy internal needs.
Those slab caches are always allocated with the SLAB_RECLAIM_ACCOUNT,
meaning allocations from the caches are going to be accounted as
SReclaimable. At the same time btrfs is not registering any shrinkers
whatsoever, thus preventing memory from the slabs to be shrunk. This
means those caches are not in fact reclaimable.

To fix this remove the SLAB_RECLAIM_ACCOUNT on all caches apart from the
inode cache, since this one is being freed by the generic VFS super_block
shrinker. Also set the transaction related caches as SLAB_TEMPORARY,
to better document the lifetime of the objects (it just translates
to SLAB_RECLAIM_ACCOUNT).

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/backref.c       | 2 +-
 fs/btrfs/delayed-inode.c | 2 +-
 fs/btrfs/delayed-ref.c   | 8 ++++----
 fs/btrfs/disk-io.c       | 2 +-
 fs/btrfs/extent_io.c     | 4 ++--
 fs/btrfs/extent_map.c    | 2 +-
 fs/btrfs/file.c          | 2 +-
 fs/btrfs/inode.c         | 8 ++++----
 fs/btrfs/ordered-data.c  | 2 +-
 9 files changed, 16 insertions(+), 16 deletions(-)

Comments

David Sterba July 11, 2016, 10:52 a.m. UTC | #1 
On Mon, Jul 11, 2016 at 12:12:21AM +0300, Nikolay Borisov wrote:
> BTRFS is using a variety of slab caches to satisfy internal needs.
> Those slab caches are always allocated with the SLAB_RECLAIM_ACCOUNT,
> meaning allocations from the caches are going to be accounted as
> SReclaimable. At the same time btrfs is not registering any shrinkers
> whatsoever, thus preventing memory from the slabs to be shrunk. This
> means those caches are not in fact reclaimable.
> 
> To fix this remove the SLAB_RECLAIM_ACCOUNT on all caches apart from the
> inode cache, since this one is being freed by the generic VFS super_block
> shrinker. Also set the transaction related caches as SLAB_TEMPORARY,
> to better document the lifetime of the objects (it just translates
> to SLAB_RECLAIM_ACCOUNT).
> 
> Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
> Reviewed-by: David Sterba <dsterba@suse.com>

FYI, patch is queued for 4.8.
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diff mbox

Patch

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 8bb3509099e8..1ac8a3c7f68e 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -139,7 +139,7 @@  int __init btrfs_prelim_ref_init(void)
 	btrfs_prelim_ref_cache = kmem_cache_create("btrfs_prelim_ref",
 					sizeof(struct __prelim_ref),
 					0,
-					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+					SLAB_MEM_SPREAD,
 					NULL);
 	if (!btrfs_prelim_ref_cache)
 		return -ENOMEM;
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 61561c2a3f96..4e5cd7dde3c5 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -34,7 +34,7 @@  int __init btrfs_delayed_inode_init(void)
 	delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
 					sizeof(struct btrfs_delayed_node),
 					0,
-					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+					SLAB_MEM_SPREAD,
 					NULL);
 	if (!delayed_node_cache)
 		return -ENOMEM;
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 430b3689b112..08e452599249 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -940,28 +940,28 @@  int btrfs_delayed_ref_init(void)
 	btrfs_delayed_ref_head_cachep = kmem_cache_create(
 				"btrfs_delayed_ref_head",
 				sizeof(struct btrfs_delayed_ref_head), 0,
-				SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+				SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_delayed_ref_head_cachep)
 		goto fail;
 
 	btrfs_delayed_tree_ref_cachep = kmem_cache_create(
 				"btrfs_delayed_tree_ref",
 				sizeof(struct btrfs_delayed_tree_ref), 0,
-				SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+				SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_delayed_tree_ref_cachep)
 		goto fail;
 
 	btrfs_delayed_data_ref_cachep = kmem_cache_create(
 				"btrfs_delayed_data_ref",
 				sizeof(struct btrfs_delayed_data_ref), 0,
-				SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+				SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_delayed_data_ref_cachep)
 		goto fail;
 
 	btrfs_delayed_extent_op_cachep = kmem_cache_create(
 				"btrfs_delayed_extent_op",
 				sizeof(struct btrfs_delayed_extent_op), 0,
-				SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+				SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_delayed_extent_op_cachep)
 		goto fail;
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 54cca7a1572b..cb1a05da5682 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -101,7 +101,7 @@  int __init btrfs_end_io_wq_init(void)
 	btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
 					sizeof(struct btrfs_end_io_wq),
 					0,
-					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+					SLAB_MEM_SPREAD,
 					NULL);
 	if (!btrfs_end_io_wq_cache)
 		return -ENOMEM;
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index aaee3ef55ed8..f3337998264d 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -163,13 +163,13 @@  int __init extent_io_init(void)
 {
 	extent_state_cache = kmem_cache_create("btrfs_extent_state",
 			sizeof(struct extent_state), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_MEM_SPREAD, NULL);
 	if (!extent_state_cache)
 		return -ENOMEM;
 
 	extent_buffer_cache = kmem_cache_create("btrfs_extent_buffer",
 			sizeof(struct extent_buffer), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_MEM_SPREAD, NULL);
 	if (!extent_buffer_cache)
 		goto free_state_cache;
 
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index e0715fcfb11e..26f9ac719d20 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -13,7 +13,7 @@  int __init extent_map_init(void)
 {
 	extent_map_cache = kmem_cache_create("btrfs_extent_map",
 			sizeof(struct extent_map), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_MEM_SPREAD, NULL);
 	if (!extent_map_cache)
 		return -ENOMEM;
 	return 0;
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index e0c9bd3fb02d..55e4d36f0c6a 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2977,7 +2977,7 @@  int btrfs_auto_defrag_init(void)
 {
 	btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
 					sizeof(struct inode_defrag), 0,
-					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+					SLAB_MEM_SPREAD,
 					NULL);
 	if (!btrfs_inode_defrag_cachep)
 		return -ENOMEM;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d2be95cfb6d1..66051c02b6de 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9383,25 +9383,25 @@  int btrfs_init_cachep(void)
 
 	btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
 			sizeof(struct btrfs_trans_handle), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_trans_handle_cachep)
 		goto fail;
 
 	btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
 			sizeof(struct btrfs_transaction), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_transaction_cachep)
 		goto fail;
 
 	btrfs_path_cachep = kmem_cache_create("btrfs_path",
 			sizeof(struct btrfs_path), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_path_cachep)
 		goto fail;
 
 	btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
 			sizeof(struct btrfs_free_space), 0,
-			SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
+			SLAB_MEM_SPREAD, NULL);
 	if (!btrfs_free_space_cachep)
 		goto fail;
 
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index e96634a725c3..c9fa1661277c 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -1121,7 +1121,7 @@  int __init ordered_data_init(void)
 {
 	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
 				     sizeof(struct btrfs_ordered_extent), 0,
-				     SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+				     SLAB_MEM_SPREAD,
 				     NULL);
 	if (!btrfs_ordered_extent_cache)
 		return -ENOMEM;