*/
static int max_queued_requests = 1024;
-static void allow_barrier(struct r1conf *conf);
+static void allow_barrier(struct r1conf *conf, sector_t start_next_window,
+ sector_t bi_sector);
static void lower_barrier(struct r1conf *conf);
static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
}
#define RESYNC_BLOCK_SIZE (64*1024)
-//#define RESYNC_BLOCK_SIZE PAGE_SIZE
+#define RESYNC_DEPTH 32
#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
#define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
-#define RESYNC_WINDOW (2048*1024)
+#define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
+#define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
+#define NEXT_NORMALIO_DISTANCE (3 * RESYNC_WINDOW_SECTORS)
static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
{
struct bio *bio = r1_bio->master_bio;
int done;
struct r1conf *conf = r1_bio->mddev->private;
+ sector_t start_next_window = r1_bio->start_next_window;
+ sector_t bi_sector = bio->bi_sector;
if (bio->bi_phys_segments) {
unsigned long flags;
bio->bi_phys_segments--;
done = (bio->bi_phys_segments == 0);
spin_unlock_irqrestore(&conf->device_lock, flags);
+ /*
+ * make_request() might be waiting for
+ * bi_phys_segments to decrease
+ */
+ wake_up(&conf->wait_barrier);
} else
done = 1;
* Wake up any possible resync thread that waits for the device
* to go idle.
*/
- allow_barrier(conf);
+ allow_barrier(conf, start_next_window, bi_sector);
}
}
* there is no normal IO happeing. It must arrange to call
* lower_barrier when the particular background IO completes.
*/
-#define RESYNC_DEPTH 32
-
static void raise_barrier(struct r1conf *conf)
{
spin_lock_irq(&conf->resync_lock);
/* block any new IO from starting */
conf->barrier++;
- /* Now wait for all pending IO to complete */
+ /* For these conditions we must wait:
+ * A: while the array is in frozen state
+ * B: while barrier >= RESYNC_DEPTH, meaning resync reach
+ * the max count which allowed.
+ * C: next_resync + RESYNC_SECTORS > start_next_window, meaning
+ * next resync will reach to the window which normal bios are
+ * handling.
+ */
wait_event_lock_irq(conf->wait_barrier,
- !conf->nr_pending && conf->barrier < RESYNC_DEPTH,
+ !conf->array_frozen &&
+ conf->barrier < RESYNC_DEPTH &&
+ (conf->start_next_window >=
+ conf->next_resync + RESYNC_SECTORS),
conf->resync_lock);
spin_unlock_irq(&conf->resync_lock);
wake_up(&conf->wait_barrier);
}
-static void wait_barrier(struct r1conf *conf)
+static bool need_to_wait_for_sync(struct r1conf *conf, struct bio *bio)
{
+ bool wait = false;
+
+ if (conf->array_frozen || !bio)
+ wait = true;
+ else if (conf->barrier && bio_data_dir(bio) == WRITE) {
+ if (conf->next_resync < RESYNC_WINDOW_SECTORS)
+ wait = true;
+ else if ((conf->next_resync - RESYNC_WINDOW_SECTORS
+ >= bio_end_sector(bio)) ||
+ (conf->next_resync + NEXT_NORMALIO_DISTANCE
+ <= bio->bi_sector))
+ wait = false;
+ else
+ wait = true;
+ }
+
+ return wait;
+}
+
+static sector_t wait_barrier(struct r1conf *conf, struct bio *bio)
+{
+ sector_t sector = 0;
+
spin_lock_irq(&conf->resync_lock);
- if (conf->barrier) {
+ if (need_to_wait_for_sync(conf, bio)) {
conf->nr_waiting++;
/* Wait for the barrier to drop.
* However if there are already pending
* count down.
*/
wait_event_lock_irq(conf->wait_barrier,
- !conf->barrier ||
- (conf->nr_pending &&
+ !conf->array_frozen &&
+ (!conf->barrier ||
+ ((conf->start_next_window <
+ conf->next_resync + RESYNC_SECTORS) &&
current->bio_list &&
- !bio_list_empty(current->bio_list)),
+ !bio_list_empty(current->bio_list))),
conf->resync_lock);
conf->nr_waiting--;
}
+
+ if (bio && bio_data_dir(bio) == WRITE) {
+ if (conf->next_resync + NEXT_NORMALIO_DISTANCE
+ <= bio->bi_sector) {
+ if (conf->start_next_window == MaxSector)
+ conf->start_next_window =
+ conf->next_resync +
+ NEXT_NORMALIO_DISTANCE;
+
+ if ((conf->start_next_window + NEXT_NORMALIO_DISTANCE)
+ <= bio->bi_sector)
+ conf->next_window_requests++;
+ else
+ conf->current_window_requests++;
+ }
+ if (bio->bi_sector >= conf->start_next_window)
+ sector = conf->start_next_window;
+ }
+
conf->nr_pending++;
spin_unlock_irq(&conf->resync_lock);
+ return sector;
}
-static void allow_barrier(struct r1conf *conf)
+static void allow_barrier(struct r1conf *conf, sector_t start_next_window,
+ sector_t bi_sector)
{
unsigned long flags;
+
spin_lock_irqsave(&conf->resync_lock, flags);
conf->nr_pending--;
+ if (start_next_window) {
+ if (start_next_window == conf->start_next_window) {
+ if (conf->start_next_window + NEXT_NORMALIO_DISTANCE
+ <= bi_sector)
+ conf->next_window_requests--;
+ else
+ conf->current_window_requests--;
+ } else
+ conf->current_window_requests--;
+
+ if (!conf->current_window_requests) {
+ if (conf->next_window_requests) {
+ conf->current_window_requests =
+ conf->next_window_requests;
+ conf->next_window_requests = 0;
+ conf->start_next_window +=
+ NEXT_NORMALIO_DISTANCE;
+ } else
+ conf->start_next_window = MaxSector;
+ }
+ }
spin_unlock_irqrestore(&conf->resync_lock, flags);
wake_up(&conf->wait_barrier);
}
{
/* stop syncio and normal IO and wait for everything to
* go quite.
- * We increment barrier and nr_waiting, and then
- * wait until nr_pending match nr_queued+extra
+ * We wait until nr_pending match nr_queued+extra
* This is called in the context of one normal IO request
* that has failed. Thus any sync request that might be pending
* will be blocked by nr_pending, and we need to wait for
* we continue.
*/
spin_lock_irq(&conf->resync_lock);
- conf->barrier++;
- conf->nr_waiting++;
+ conf->array_frozen = 1;
wait_event_lock_irq_cmd(conf->wait_barrier,
conf->nr_pending == conf->nr_queued+extra,
conf->resync_lock,
{
/* reverse the effect of the freeze */
spin_lock_irq(&conf->resync_lock);
- conf->barrier--;
- conf->nr_waiting--;
+ conf->array_frozen = 0;
wake_up(&conf->wait_barrier);
spin_unlock_irq(&conf->resync_lock);
}
int first_clone;
int sectors_handled;
int max_sectors;
+ sector_t start_next_window;
/*
* Register the new request and wait if the reconstruction
finish_wait(&conf->wait_barrier, &w);
}
- wait_barrier(conf);
+ start_next_window = wait_barrier(conf, bio);
bitmap = mddev->bitmap;
disks = conf->raid_disks * 2;
retry_write:
+ r1_bio->start_next_window = start_next_window;
blocked_rdev = NULL;
rcu_read_lock();
max_sectors = r1_bio->sectors;
if (unlikely(blocked_rdev)) {
/* Wait for this device to become unblocked */
int j;
+ sector_t old = start_next_window;
for (j = 0; j < i; j++)
if (r1_bio->bios[j])
rdev_dec_pending(conf->mirrors[j].rdev, mddev);
r1_bio->state = 0;
- allow_barrier(conf);
+ allow_barrier(conf, start_next_window, bio->bi_sector);
md_wait_for_blocked_rdev(blocked_rdev, mddev);
- wait_barrier(conf);
+ start_next_window = wait_barrier(conf, bio);
+ /*
+ * We must make sure the multi r1bios of bio have
+ * the same value of bi_phys_segments
+ */
+ if (bio->bi_phys_segments && old &&
+ old != start_next_window)
+ /* Wait for the former r1bio(s) to complete */
+ wait_event(conf->wait_barrier,
+ bio->bi_phys_segments == 1);
goto retry_write;
}
static void close_sync(struct r1conf *conf)
{
- wait_barrier(conf);
- allow_barrier(conf);
+ wait_barrier(conf, NULL);
+ allow_barrier(conf, 0, 0);
mempool_destroy(conf->r1buf_pool);
conf->r1buf_pool = NULL;
+
+ conf->next_resync = 0;
+ conf->start_next_window = MaxSector;
}
static int raid1_spare_active(struct mddev *mddev)
conf->pending_count = 0;
conf->recovery_disabled = mddev->recovery_disabled - 1;
+ conf->start_next_window = MaxSector;
+ conf->current_window_requests = conf->next_window_requests = 0;
+
err = -EIO;
for (i = 0; i < conf->raid_disks * 2; i++) {
atomic_read(&bitmap->behind_writes) == 0);
}
- raise_barrier(conf);
- lower_barrier(conf);
+ freeze_array(conf, 0);
+ unfreeze_array(conf);
md_unregister_thread(&mddev->thread);
if (conf->r1bio_pool)
wake_up(&conf->wait_barrier);
break;
case 1:
- raise_barrier(conf);
+ freeze_array(conf, 0);
break;
case 0:
- lower_barrier(conf);
+ unfreeze_array(conf);
break;
}
}
mddev->new_chunk_sectors = 0;
conf = setup_conf(mddev);
if (!IS_ERR(conf))
- conf->barrier = 1;
+ /* Array must appear to be quiesced */
+ conf->array_frozen = 1;
return conf;
}
return ERR_PTR(-EINVAL);
projects / ~andy / linux / blobdiff