From 83de75cc92be599850e5ef3928e07cd840833499 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Sat, 28 Jun 2008 08:31:58 +1000 Subject: [PATCH] md: replace STRIPE_OP_BIOFILL with STRIPE_BIOFILL_RUN From: Dan Williams Track the state of read operations (copying data from the stripe cache to bio buffers outside the lock) with a state flag. Reduce the scope of the STRIPE_OP_BIOFILL flag to only tracking whether a biofill operation has been requested via the ops_request field of struct stripe_head_state. This is another step towards the removal of ops.{pending,ack,complete,count}, i.e. STRIPE_OP_BIOFILL only requests an operation and does not track the state of the operation. Signed-off-by: Dan Williams Signed-off-by: Neil Brown --- drivers/md/raid5.c | 33 ++++++++++++--------------------- 1 file changed, 12 insertions(+), 21 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 544e1600f20..b9c0a32a4f9 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -523,38 +523,34 @@ static void ops_complete_biofill(void *stripe_head_ref) (unsigned long long)sh->sector); /* clear completed biofills */ + spin_lock_irq(&conf->device_lock); for (i = sh->disks; i--; ) { struct r5dev *dev = &sh->dev[i]; /* acknowledge completion of a biofill operation */ /* and check if we need to reply to a read request, * new R5_Wantfill requests are held off until - * !test_bit(STRIPE_OP_BIOFILL, &sh->ops.pending) + * !STRIPE_BIOFILL_RUN */ if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { struct bio *rbi, *rbi2; - /* The access to dev->read is outside of the - * spin_lock_irq(&conf->device_lock), but is protected - * by the STRIPE_OP_BIOFILL pending bit - */ BUG_ON(!dev->read); rbi = dev->read; dev->read = NULL; while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { rbi2 = r5_next_bio(rbi, dev->sector); - spin_lock_irq(&conf->device_lock); if (--rbi->bi_phys_segments == 0) { rbi->bi_next = return_bi; return_bi = rbi; } - spin_unlock_irq(&conf->device_lock); rbi = rbi2; } } } - set_bit(STRIPE_OP_BIOFILL, &sh->ops.complete); + spin_unlock_irq(&conf->device_lock); + clear_bit(STRIPE_BIOFILL_RUN, &sh->state); return_io(return_bi); @@ -880,7 +876,7 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long pending, int overlap_clear = 0, i, disks = sh->disks; struct dma_async_tx_descriptor *tx = NULL; - if (test_bit(STRIPE_OP_BIOFILL, &pending)) { + if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { ops_run_biofill(sh); overlap_clear++; } @@ -2630,15 +2626,8 @@ static void handle_stripe5(struct stripe_head *sh) s.syncing = test_bit(STRIPE_SYNCING, &sh->state); s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); + /* Now to look around and see what can be done */ - - /* clean-up completed biofill operations */ - if (test_bit(STRIPE_OP_BIOFILL, &sh->ops.complete)) { - clear_bit(STRIPE_OP_BIOFILL, &sh->ops.pending); - clear_bit(STRIPE_OP_BIOFILL, &sh->ops.ack); - clear_bit(STRIPE_OP_BIOFILL, &sh->ops.complete); - } - rcu_read_lock(); for (i=disks; i--; ) { mdk_rdev_t *rdev; @@ -2652,10 +2641,10 @@ static void handle_stripe5(struct stripe_head *sh) /* maybe we can request a biofill operation * * new wantfill requests are only permitted while - * STRIPE_OP_BIOFILL is clear + * ops_complete_biofill is guaranteed to be inactive */ if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && - !test_bit(STRIPE_OP_BIOFILL, &sh->ops.pending)) + !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) set_bit(R5_Wantfill, &dev->flags); /* now count some things */ @@ -2699,8 +2688,10 @@ static void handle_stripe5(struct stripe_head *sh) goto unlock; } - if (s.to_fill && !test_and_set_bit(STRIPE_OP_BIOFILL, &sh->ops.pending)) - sh->ops.count++; + 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\n",