[dm-devel] [dm-6.4 PATCH v3 09/20] dm bufio: move dm_bufio_client members to avoid spanning cachelines

Mike Snitzer
2023-03-27T20:13:47Z

Movement also consolidates holes in dm_bufio_client struct. But the
overall size of the struct isn't changed.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
---
drivers/md/dm-bufio.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 9ac50024006d..e5459741335d 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -936,13 +936,16 @@ static void cache_remove_range(struct dm_buffer_cache *bc,
* context.
*/
struct dm_bufio_client {
- struct mutex lock;
- spinlock_t spinlock;
- bool no_sleep;
-
struct block_device *bdev;
unsigned int block_size;
s8 sectors_per_block_bits;
+
+ bool no_sleep;
+ struct mutex lock;
+ spinlock_t spinlock;
+
+ int async_write_error;
+
void (*alloc_callback)(struct dm_buffer *buf);
void (*write_callback)(struct dm_buffer *buf);
struct kmem_cache *slab_buffer;
@@ -954,23 +957,22 @@ struct dm_bufio_client {

unsigned int minimum_buffers;

- struct dm_buffer_cache cache;
- wait_queue_head_t free_buffer_wait;
-
sector_t start;

- int async_write_error;
-
- struct list_head client_list;
-
struct shrinker shrinker;
struct work_struct shrink_work;
atomic_long_t need_shrink;

+ wait_queue_head_t free_buffer_wait;
+
+ struct list_head client_list;
+
/*
* Used by global_cleanup to sort the clients list.
*/
unsigned long oldest_buffer;
+
+ struct dm_buffer_cache cache;
};

static DEFINE_STATIC_KEY_FALSE(no_sleep_enabled);