[patch v2 6/6] raid5: handle expansion/resync case with stripe batching
From: shli@kernel.org
Date: 2014-09-10 12:40:15
expansion/resync can grab a stripe when the stripe is in batch list. Since all stripes in batch list must be in the same state, we can't allow some stripes run into expansion/resync. So we delay expansion/resync for stripe in batch list. Signed-off-by: Shaohua Li <redacted> --- drivers/md/raid5.c | 22 +++++++++++++++------- drivers/md/raid5.h | 5 +++++ 2 files changed, 20 insertions(+), 7 deletions(-) Index: linux/drivers/md/raid5.c ===================================================================
--- linux.orig/drivers/md/raid5.c 2014-09-10 19:21:16.759271053 +0800
+++ linux/drivers/md/raid5.c 2014-09-10 19:21:16.755271103 +0800@@ -3371,8 +3371,10 @@ unhash: struct stripe_head, batch_list); list_del_init(&sh->batch_list); - sh->state = head_sh->state & (~((1 << STRIPE_ACTIVE) | - (1 << STRIPE_PREREAD_ACTIVE))); + set_mask_bits(&sh->state, ~STRIPE_EXPAND_SYNC_FLAG, + head_sh->state & (~((1 << STRIPE_ACTIVE) | + (1 << STRIPE_PREREAD_ACTIVE) | + STRIPE_EXPAND_SYNC_FLAG))); sh->check_state = head_sh->check_state; sh->reconstruct_state = head_sh->reconstruct_state; for (i = 0; i < sh->disks; i++) {
@@ -3384,6 +3386,8 @@ unhash: spin_lock_irq(&sh->stripe_lock); sh->batch_head = NULL; spin_unlock_irq(&sh->stripe_lock); + if (sh->state & STRIPE_EXPAND_SYNC_FLAG) + set_bit(STRIPE_HANDLE, &sh->state); release_stripe(sh); }
@@ -3391,6 +3395,8 @@ unhash: head_sh->batch_head = NULL; spin_unlock_irq(&head_sh->stripe_lock); wake_up_nr(&conf->wait_for_overlap, wakeup_nr); + if (head_sh->state & STRIPE_EXPAND_SYNC_FLAG) + set_bit(STRIPE_HANDLE, &head_sh->state); } static void handle_stripe_dirtying(struct r5conf *conf,
@@ -3853,8 +3859,8 @@ static void analyse_stripe(struct stripe memset(s, 0, sizeof(*s)); - s->expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); - s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); + s->expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state) && !sh->batch_head; + s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state) && !sh->batch_head; s->failed_num[0] = -1; s->failed_num[1] = -1;
@@ -4076,8 +4082,10 @@ static void check_break_stripe_batch_lis struct stripe_head, batch_list); list_del_init(&sh->batch_list); - sh->state = head_sh->state & (~((1 << STRIPE_ACTIVE) | - (1 << STRIPE_PREREAD_ACTIVE) | (1 << STRIPE_DEGRADED))); + set_mask_bits(&sh->state, ~STRIPE_EXPAND_SYNC_FLAG, + head_sh->state & (~((1 << STRIPE_ACTIVE) | + (1 << STRIPE_PREREAD_ACTIVE) | (1 << STRIPE_DEGRADED) | + STRIPE_EXPAND_SYNC_FLAG))); sh->check_state = head_sh->check_state; sh->reconstruct_state = head_sh->reconstruct_state; for (i = 0; i < sh->disks; i++)
@@ -4119,7 +4127,7 @@ static void handle_stripe(struct stripe_ check_break_stripe_batch_list(sh); - if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state)) { + if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state) && !sh->batch_head) { spin_lock(&sh->stripe_lock); /* Cannot process 'sync' concurrently with 'discard' */ if (!test_bit(STRIPE_DISCARD, &sh->state) &&
Index: linux/drivers/md/raid5.h ===================================================================
--- linux.orig/drivers/md/raid5.h 2014-09-10 19:21:16.759271053 +0800
+++ linux/drivers/md/raid5.h 2014-09-10 19:21:16.755271103 +0800@@ -339,6 +339,11 @@ enum { STRIPE_BATCH_ERR, }; +#define STRIPE_EXPAND_SYNC_FLAG \ + ((1 << STRIPE_EXPAND_SOURCE) |\ + (1 << STRIPE_EXPAND_READY) |\ + (1 << STRIPE_EXPANDING) |\ + (1 << STRIPE_SYNC_REQUESTED)) /* * Operation request flags */