dm mpath: reduce size of struct multipath
Move multipath structure's 'lock' and 'queue_size' members to eliminate
two 4-byte holes. Also use a bit within a single unsigned int for each
existing flag (saves 8-bytes). This allows future flags to be added
without each consuming an unsigned int.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 754f38f..c351607 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -61,11 +61,11 @@
struct list_head list;
struct dm_target *ti;
- spinlock_t lock;
-
const char *hw_handler_name;
char *hw_handler_params;
+ spinlock_t lock;
+
unsigned nr_priority_groups;
struct list_head priority_groups;
@@ -81,16 +81,17 @@
struct priority_group *next_pg; /* Switch to this PG if set */
unsigned repeat_count; /* I/Os left before calling PS again */
- unsigned queue_io; /* Must we queue all I/O? */
- unsigned queue_if_no_path; /* Queue I/O if last path fails? */
- unsigned saved_queue_if_no_path;/* Saved state during suspension */
+ unsigned queue_io:1; /* Must we queue all I/O? */
+ unsigned queue_if_no_path:1; /* Queue I/O if last path fails? */
+ unsigned saved_queue_if_no_path:1; /* Saved state during suspension */
+
unsigned pg_init_retries; /* Number of times to retry pg_init */
unsigned pg_init_count; /* Number of times pg_init called */
unsigned pg_init_delay_msecs; /* Number of msecs before pg_init retry */
+ unsigned queue_size;
struct work_struct process_queued_ios;
struct list_head queued_ios;
- unsigned queue_size;
struct work_struct trigger_event;