From 6c0069c0ae9659e3a91b68eaed06a5c6c37f45c8 Mon Sep 17 00:00:00 2001 From: Yuri Tikhonov Date: Sat, 29 Aug 2009 19:13:13 -0700 Subject: [PATCH] md/raid6: asynchronous handle_stripe6 1/ Use STRIPE_OP_BIOFILL to offload completion of read requests to raid_run_ops 2/ Implement a handler for sh->reconstruct_state similar to the raid5 case (adds handling of Q parity) 3/ Prevent handle_parity_checks6 from running concurrently with 'compute' operations 4/ Hook up raid_run_ops Signed-off-by: Yuri Tikhonov Signed-off-by: Ilya Yanok Signed-off-by: Dan Williams --- drivers/md/raid5.c | 120 +++++++++++++++++++++++++++++++-------------- 1 file changed, 82 insertions(+), 38 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 3c31f7f8aa6..a833de189ca 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3424,9 +3424,10 @@ static bool handle_stripe6(struct stripe_head *sh) mdk_rdev_t *blocked_rdev = NULL; pr_debug("handling stripe %llu, state=%#lx cnt=%d, " - "pd_idx=%d, qd_idx=%d\n", + "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n", (unsigned long long)sh->sector, sh->state, - atomic_read(&sh->count), pd_idx, qd_idx); + atomic_read(&sh->count), pd_idx, qd_idx, + sh->check_state, sh->reconstruct_state); memset(&s, 0, sizeof(s)); spin_lock(&sh->lock); @@ -3446,35 +3447,24 @@ static bool handle_stripe6(struct stripe_head *sh) pr_debug("check %d: state 0x%lx read %p write %p written %p\n", i, dev->flags, dev->toread, dev->towrite, dev->written); - /* maybe we can reply to a read */ - if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { - struct bio *rbi, *rbi2; - pr_debug("Return read for disc %d\n", i); - spin_lock_irq(&conf->device_lock); - rbi = dev->toread; - dev->toread = NULL; - if (test_and_clear_bit(R5_Overlap, &dev->flags)) - wake_up(&conf->wait_for_overlap); - spin_unlock_irq(&conf->device_lock); - while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { - copy_data(0, rbi, dev->page, dev->sector); - rbi2 = r5_next_bio(rbi, dev->sector); - spin_lock_irq(&conf->device_lock); - if (!raid5_dec_bi_phys_segments(rbi)) { - rbi->bi_next = return_bi; - return_bi = rbi; - } - spin_unlock_irq(&conf->device_lock); - rbi = rbi2; - } - } + /* maybe we can reply to a read + * + * new wantfill requests are only permitted while + * ops_complete_biofill is guaranteed to be inactive + */ + if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && + !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) + set_bit(R5_Wantfill, &dev->flags); /* now count some things */ if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; + if (test_bit(R5_Wantcompute, &dev->flags)) + BUG_ON(++s.compute > 2); - - if (dev->toread) + if (test_bit(R5_Wantfill, &dev->flags)) { + s.to_fill++; + } else if (dev->toread) s.to_read++; if (dev->towrite) { s.to_write++; @@ -3515,6 +3505,11 @@ static bool handle_stripe6(struct stripe_head *sh) blocked_rdev = NULL; } + if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { + set_bit(STRIPE_OP_BIOFILL, &s.ops_request); + set_bit(STRIPE_BIOFILL_RUN, &sh->state); + } + pr_debug("locked=%d uptodate=%d to_read=%d" " to_write=%d failed=%d failed_num=%d,%d\n", s.locked, s.uptodate, s.to_read, s.to_write, s.failed, @@ -3555,9 +3550,43 @@ static bool handle_stripe6(struct stripe_head *sh) * or to load a block that is being partially written. */ if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || - (s.syncing && (s.uptodate < disks)) || s.expanding) + (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding) handle_stripe_fill6(sh, &s, &r6s, disks); + /* Now we check to see if any write operations have recently + * completed + */ + if (sh->reconstruct_state == reconstruct_state_drain_result) { + int qd_idx = sh->qd_idx; + + sh->reconstruct_state = reconstruct_state_idle; + /* All the 'written' buffers and the parity blocks are ready to + * be written back to disk + */ + BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); + BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[qd_idx].flags)); + for (i = disks; i--; ) { + dev = &sh->dev[i]; + if (test_bit(R5_LOCKED, &dev->flags) && + (i == sh->pd_idx || i == qd_idx || + dev->written)) { + pr_debug("Writing block %d\n", i); + BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); + set_bit(R5_Wantwrite, &dev->flags); + if (!test_bit(R5_Insync, &dev->flags) || + ((i == sh->pd_idx || i == qd_idx) && + s.failed == 0)) + set_bit(STRIPE_INSYNC, &sh->state); + } + } + if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { + atomic_dec(&conf->preread_active_stripes); + if (atomic_read(&conf->preread_active_stripes) < + IO_THRESHOLD) + md_wakeup_thread(conf->mddev->thread); + } + } + /* Now to consider new write requests and what else, if anything * should be read. We do not handle new writes when: * 1/ A 'write' operation (copy+gen_syndrome) is already in flight. @@ -3569,9 +3598,13 @@ static bool handle_stripe6(struct stripe_head *sh) /* maybe we need to check and possibly fix the parity for this stripe * Any reads will already have been scheduled, so we just see if enough - * data is available + * data is available. The parity check is held off while parity + * dependent operations are in flight. */ - if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) + if (sh->check_state || + (s.syncing && s.locked == 0 && + !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && + !test_bit(STRIPE_INSYNC, &sh->state))) handle_parity_checks6(conf, sh, &s, &r6s, disks); if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { @@ -3593,15 +3626,29 @@ static bool handle_stripe6(struct stripe_head *sh) set_bit(R5_Wantwrite, &dev->flags); set_bit(R5_ReWrite, &dev->flags); set_bit(R5_LOCKED, &dev->flags); + s.locked++; } else { /* let's read it back */ set_bit(R5_Wantread, &dev->flags); set_bit(R5_LOCKED, &dev->flags); + s.locked++; } } } - if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { + /* Finish reconstruct operations initiated by the expansion process */ + if (sh->reconstruct_state == reconstruct_state_result) { + sh->reconstruct_state = reconstruct_state_idle; + clear_bit(STRIPE_EXPANDING, &sh->state); + for (i = conf->raid_disks; i--; ) { + set_bit(R5_Wantwrite, &sh->dev[i].flags); + set_bit(R5_LOCKED, &sh->dev[i].flags); + s.locked++; + } + } + + if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && + !sh->reconstruct_state) { struct stripe_head *sh2 = get_active_stripe(conf, sh->sector, 1, 1); if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) { @@ -3622,14 +3669,8 @@ static bool handle_stripe6(struct stripe_head *sh) /* Need to write out all blocks after computing P&Q */ sh->disks = conf->raid_disks; stripe_set_idx(sh->sector, conf, 0, sh); - compute_parity6(sh, RECONSTRUCT_WRITE); - for (i = conf->raid_disks ; i-- ; ) { - set_bit(R5_LOCKED, &sh->dev[i].flags); - s.locked++; - set_bit(R5_Wantwrite, &sh->dev[i].flags); - } - clear_bit(STRIPE_EXPANDING, &sh->state); - } else if (s.expanded) { + schedule_reconstruction(sh, &s, 1, 1); + } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { clear_bit(STRIPE_EXPAND_READY, &sh->state); atomic_dec(&conf->reshape_stripes); wake_up(&conf->wait_for_overlap); @@ -3647,6 +3688,9 @@ static bool handle_stripe6(struct stripe_head *sh) if (unlikely(blocked_rdev)) md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); + if (s.ops_request) + raid_run_ops(sh, s.ops_request); + ops_run_io(sh, &s); return_io(return_bi); -- 2.41.0