Eliminate 1 4-byte hole in 'struct dm_io_memory' by moving 'offset'
above the 'ptr' to which it applies (size reduced from 24 to 16 bytes).
And by association, 1-4 byte hole is eliminated in 'struct
dm_io_request' (size reduced from 56 to 48 bytes).
Eliminate all (6 4-byte) holes (and 1 cache-line) in 'struct
dm_snapshot' (size reduced from 392 to 368 bytes).
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
drivers/md/dm-snap.c | 26 +++++++++++++-------------
include/linux/dm-io.h | 4 ++--
2 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index ee8eb28..ab9822e 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -83,10 +83,10 @@ struct dm_snapshot {
/* Whether or not owning mapped_device is suspended */
int suspended;
- mempool_t *pending_pool;
-
atomic_t pending_exceptions_count;
+ mempool_t *pending_pool;
+
struct dm_exception_table pending;
struct dm_exception_table complete;
@@ -96,6 +96,11 @@ struct dm_snapshot {
*/
spinlock_t pe_lock;
+ /* Chunks with outstanding reads */
+ spinlock_t tracked_chunk_lock;
+ mempool_t *tracked_chunk_pool;
+ struct hlist_head tracked_chunk_hash[DM_TRACKED_CHUNK_HASH_SIZE];
+
/* The on disk metadata handler */
struct dm_exception_store *store;
@@ -105,10 +110,12 @@ struct dm_snapshot {
struct bio_list queued_bios;
struct work_struct queued_bios_work;
- /* Chunks with outstanding reads */
- mempool_t *tracked_chunk_pool;
- spinlock_t tracked_chunk_lock;
- struct hlist_head tracked_chunk_hash[DM_TRACKED_CHUNK_HASH_SIZE];
+ /* Wait for events based on state_bits */
+ unsigned long state_bits;
+
+ /* Range of chunks currently being merged. */
+ chunk_t first_merging_chunk;
+ int num_merging_chunks;
/*
* The merge operation failed if this flag is set.
@@ -125,13 +132,6 @@ struct dm_snapshot {
*/
int merge_failed;
- /* Wait for events based on state_bits */
- unsigned long state_bits;
-
- /* Range of chunks currently being merged. */
- chunk_t first_merging_chunk;
- int num_merging_chunks;
-
/*
* Incoming bios that overlap with chunks being merged must wait
* for them to be committed.
diff --git a/include/linux/dm-io.h b/include/linux/dm-io.h
index b6bf17e..5c9186b 100644
--- a/include/linux/dm-io.h
+++ b/include/linux/dm-io.h
@@ -37,14 +37,14 @@ enum dm_io_mem_type {
struct dm_io_memory {
enum dm_io_mem_type type;
+ unsigned offset;
+
union {
struct page_list *pl;
struct bio_vec *bvec;
void *vma;
void *addr;
} ptr;
-
- unsigned offset;
};
struct dm_io_notify {
--
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