diff options
Diffstat (limited to 'drivers/md/raid1.h')
| -rw-r--r-- | drivers/md/raid1.h | 58 |
1 files changed, 34 insertions, 24 deletions
diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h index c52ef424a24b..dd22a37d0d83 100644 --- a/drivers/md/raid1.h +++ b/drivers/md/raid1.h @@ -1,6 +1,30 @@ #ifndef _RAID1_H #define _RAID1_H +/* + * each barrier unit size is 64MB fow now + * note: it must be larger than RESYNC_DEPTH + */ +#define BARRIER_UNIT_SECTOR_BITS 17 +#define BARRIER_UNIT_SECTOR_SIZE (1<<17) +/* + * In struct r1conf, the following members are related to I/O barrier + * buckets, + * atomic_t *nr_pending; + * atomic_t *nr_waiting; + * atomic_t *nr_queued; + * atomic_t *barrier; + * Each of them points to array of atomic_t variables, each array is + * designed to have BARRIER_BUCKETS_NR elements and occupy a single + * memory page. The data width of atomic_t variables is 4 bytes, equal + * to 1<<(ilog2(sizeof(atomic_t))), BARRIER_BUCKETS_NR_BITS is defined + * as (PAGE_SHIFT - ilog2(sizeof(int))) to make sure an array of + * atomic_t variables with BARRIER_BUCKETS_NR elements just exactly + * occupies a single memory page. + */ +#define BARRIER_BUCKETS_NR_BITS (PAGE_SHIFT - ilog2(sizeof(atomic_t))) +#define BARRIER_BUCKETS_NR (1<<BARRIER_BUCKETS_NR_BITS) + struct raid1_info { struct md_rdev *rdev; sector_t head_position; @@ -35,25 +59,6 @@ struct r1conf { */ int raid_disks; - /* During resync, read_balancing is only allowed on the part - * of the array that has been resynced. 'next_resync' tells us - * where that is. - */ - sector_t next_resync; - - /* When raid1 starts resync, we divide array into four partitions - * |---------|--------------|---------------------|-------------| - * next_resync start_next_window end_window - * start_next_window = next_resync + NEXT_NORMALIO_DISTANCE - * end_window = start_next_window + NEXT_NORMALIO_DISTANCE - * current_window_requests means the count of normalIO between - * start_next_window and end_window. - * next_window_requests means the count of normalIO after end_window. - * */ - sector_t start_next_window; - int current_window_requests; - int next_window_requests; - spinlock_t device_lock; /* list of 'struct r1bio' that need to be processed by raid1d, @@ -79,10 +84,10 @@ struct r1conf { */ wait_queue_head_t wait_barrier; spinlock_t resync_lock; - int nr_pending; - int nr_waiting; - int nr_queued; - int barrier; + atomic_t *nr_pending; + atomic_t *nr_waiting; + atomic_t *nr_queued; + atomic_t *barrier; int array_frozen; /* Set to 1 if a full sync is needed, (fresh device added). @@ -135,7 +140,6 @@ struct r1bio { * in this BehindIO request */ sector_t sector; - sector_t start_next_window; int sectors; unsigned long state; struct mddev *mddev; @@ -185,4 +189,10 @@ enum r1bio_state { R1BIO_WriteError, R1BIO_FailFast, }; + +static inline int sector_to_idx(sector_t sector) +{ + return hash_long(sector >> BARRIER_UNIT_SECTOR_BITS, + BARRIER_BUCKETS_NR_BITS); +} #endif |