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authorMikulas Patocka <mpatocka@redhat.com>2009-12-10 23:51:57 +0000
committerAlasdair G Kergon <agk@redhat.com>2009-12-10 23:51:57 +0000
commit952b355760c196ec014dd0b6878f85a11496e3da (patch)
tree0a6907fa6dce2bac8afdc2efea774f19bdbb9a17 /drivers/md/dm-io.c
parent542da317668c35036e8471822a564b609d05af66 (diff)
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dm io: use slab for struct io
Allocate "struct io" from a slab. This patch changes dm-io, so that "struct io" is allocated from a slab cache. It used to be allocated with kmalloc. Allocating from a slab will be needed for the next patch, because it requires a special alignment of "struct io" and kmalloc cannot meet this alignment. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'drivers/md/dm-io.c')
-rw-r--r--drivers/md/dm-io.c21
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 3a2e6a2f8bdd..b0d264e684fd 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -5,6 +5,8 @@
* This file is released under the GPL.
*/
+#include "dm.h"
+
#include <linux/device-mapper.h>
#include <linux/bio.h>
@@ -30,6 +32,8 @@ struct io {
void *context;
};
+static struct kmem_cache *_dm_io_cache;
+
/*
* io contexts are only dynamically allocated for asynchronous
* io. Since async io is likely to be the majority of io we'll
@@ -53,7 +57,7 @@ struct dm_io_client *dm_io_client_create(unsigned num_pages)
if (!client)
return ERR_PTR(-ENOMEM);
- client->pool = mempool_create_kmalloc_pool(ios, sizeof(struct io));
+ client->pool = mempool_create_slab_pool(ios, _dm_io_cache);
if (!client->pool)
goto bad;
@@ -472,3 +476,18 @@ int dm_io(struct dm_io_request *io_req, unsigned num_regions,
&dp, io_req->notify.fn, io_req->notify.context);
}
EXPORT_SYMBOL(dm_io);
+
+int __init dm_io_init(void)
+{
+ _dm_io_cache = KMEM_CACHE(io, 0);
+ if (!_dm_io_cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void dm_io_exit(void)
+{
+ kmem_cache_destroy(_dm_io_cache);
+ _dm_io_cache = NULL;
+}