From d60de03a6694302b691bdf858ede9cbdfb7112d6 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Thu, 17 Nov 2011 10:12:31 +0100 Subject: drbd: Load balancing method: striping Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_req.c | 13 +++++++++++-- include/linux/drbd.h | 6 ++++++ 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 98251e2a7fb7..5b28de0c5960 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -745,10 +745,11 @@ static bool drbd_may_do_local_read(struct drbd_conf *mdev, sector_t sector, int return drbd_bm_count_bits(mdev, sbnr, ebnr) == 0; } -static bool remote_due_to_read_balancing(struct drbd_conf *mdev) +static bool remote_due_to_read_balancing(struct drbd_conf *mdev, sector_t sector) { enum drbd_read_balancing rbm; struct backing_dev_info *bdi; + int stripe_shift; if (mdev->state.pdsk < D_UP_TO_DATE) return false; @@ -764,6 +765,14 @@ static bool remote_due_to_read_balancing(struct drbd_conf *mdev) case RB_LEAST_PENDING: return atomic_read(&mdev->local_cnt) > atomic_read(&mdev->ap_pending_cnt) + atomic_read(&mdev->rs_pending_cnt); + case RB_32K_STRIPING: /* stripe_shift = 15 */ + case RB_64K_STRIPING: + case RB_128K_STRIPING: + case RB_256K_STRIPING: + case RB_512K_STRIPING: + case RB_1M_STRIPING: /* stripe_shift = 20 */ + stripe_shift = (rbm - RB_32K_STRIPING + 15); + return (sector >> (stripe_shift - 9)) & 1; case RB_ROUND_ROBIN: return test_and_change_bit(READ_BALANCE_RR, &mdev->flags); case RB_PREFER_REMOTE: @@ -841,7 +850,7 @@ int __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long s bio_put(req->private_bio); req->private_bio = NULL; put_ldev(mdev); - } else if (remote_due_to_read_balancing(mdev)) { + } else if (remote_due_to_read_balancing(mdev, sector)) { /* Keep the private bio in case we need it for a local retry */ local = 0; diff --git a/include/linux/drbd.h b/include/linux/drbd.h index 157ba3d74dc7..1e86156c10f7 100644 --- a/include/linux/drbd.h +++ b/include/linux/drbd.h @@ -108,6 +108,12 @@ enum drbd_read_balancing { RB_ROUND_ROBIN, RB_LEAST_PENDING, RB_CONGESTED_REMOTE, + RB_32K_STRIPING, + RB_64K_STRIPING, + RB_128K_STRIPING, + RB_256K_STRIPING, + RB_512K_STRIPING, + RB_1M_STRIPING, }; /* KEEP the order, do not delete or insert. Only append. */ -- cgit v1.2.3