diff options
-rw-r--r-- | drivers/md/raid5-cache.c | 411 | ||||
-rw-r--r-- | drivers/md/raid5.c | 21 | ||||
-rw-r--r-- | drivers/md/raid5.h | 39 |
3 files changed, 430 insertions, 41 deletions
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 19c5af91bd1b..7dec2a04ca26 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -29,12 +29,21 @@ #define BLOCK_SECTORS (8) /* - * reclaim runs every 1/4 disk size or 10G reclaimable space. This can prevent - * recovery scans a very long log + * log->max_free_space is min(1/4 disk size, 10G reclaimable space). + * + * In write through mode, the reclaim runs every log->max_free_space. + * This can prevent the recovery scans for too long */ #define RECLAIM_MAX_FREE_SPACE (10 * 1024 * 1024 * 2) /* sector */ #define RECLAIM_MAX_FREE_SPACE_SHIFT (2) +/* wake up reclaim thread periodically */ +#define R5C_RECLAIM_WAKEUP_INTERVAL (30 * HZ) +/* start flush with these full stripes */ +#define R5C_FULL_STRIPE_FLUSH_BATCH 256 +/* reclaim stripes in groups */ +#define R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2) + /* * We only need 2 bios per I/O unit to make progress, but ensure we * have a few more available to not get too tight. @@ -141,6 +150,12 @@ struct r5l_log { /* for r5c_cache */ enum r5c_journal_mode r5c_journal_mode; + + /* all stripes in r5cache, in the order of seq at sh->log_start */ + struct list_head stripe_in_journal_list; + + spinlock_t stripe_in_journal_lock; + atomic_t stripe_in_journal_count; }; /* @@ -256,11 +271,109 @@ void r5c_handle_cached_data_endio(struct r5conf *conf, } } +/* Check whether we should flush some stripes to free up stripe cache */ +void r5c_check_stripe_cache_usage(struct r5conf *conf) +{ + int total_cached; + + if (!r5c_is_writeback(conf->log)) + return; + + total_cached = atomic_read(&conf->r5c_cached_partial_stripes) + + atomic_read(&conf->r5c_cached_full_stripes); + + /* + * The following condition is true for either of the following: + * - stripe cache pressure high: + * total_cached > 3/4 min_nr_stripes || + * empty_inactive_list_nr > 0 + * - stripe cache pressure moderate: + * total_cached > 1/2 min_nr_stripes + */ + if (total_cached > conf->min_nr_stripes * 1 / 2 || + atomic_read(&conf->empty_inactive_list_nr) > 0) + r5l_wake_reclaim(conf->log, 0); +} + +/* + * flush cache when there are R5C_FULL_STRIPE_FLUSH_BATCH or more full + * stripes in the cache + */ +void r5c_check_cached_full_stripe(struct r5conf *conf) +{ + if (!r5c_is_writeback(conf->log)) + return; + + /* + * wake up reclaim for R5C_FULL_STRIPE_FLUSH_BATCH cached stripes + * or a full stripe (chunk size / 4k stripes). + */ + if (atomic_read(&conf->r5c_cached_full_stripes) >= + min(R5C_FULL_STRIPE_FLUSH_BATCH, + conf->chunk_sectors >> STRIPE_SHIFT)) + r5l_wake_reclaim(conf->log, 0); +} + +/* + * Total log space (in sectors) needed to flush all data in cache + * + * Currently, writing-out phase automatically includes all pending writes + * to the same sector. So the reclaim of each stripe takes up to + * (conf->raid_disks + 1) pages of log space. + * + * To totally avoid deadlock due to log space, the code reserves + * (conf->raid_disks + 1) pages for each stripe in cache, which is not + * necessary in most cases. + * + * To improve this, we will need writing-out phase to be able to NOT include + * pending writes, which will reduce the requirement to + * (conf->max_degraded + 1) pages per stripe in cache. + */ +static sector_t r5c_log_required_to_flush_cache(struct r5conf *conf) +{ + struct r5l_log *log = conf->log; + + if (!r5c_is_writeback(log)) + return 0; + + return BLOCK_SECTORS * (conf->raid_disks + 1) * + atomic_read(&log->stripe_in_journal_count); +} + +/* + * evaluate log space usage and update R5C_LOG_TIGHT and R5C_LOG_CRITICAL + * + * R5C_LOG_TIGHT is set when free space on the log device is less than 3x of + * reclaim_required_space. R5C_LOG_CRITICAL is set when free space on the log + * device is less than 2x of reclaim_required_space. + */ +static inline void r5c_update_log_state(struct r5l_log *log) +{ + struct r5conf *conf = log->rdev->mddev->private; + sector_t free_space; + sector_t reclaim_space; + + if (!r5c_is_writeback(log)) + return; + + free_space = r5l_ring_distance(log, log->log_start, + log->last_checkpoint); + reclaim_space = r5c_log_required_to_flush_cache(conf); + if (free_space < 2 * reclaim_space) + set_bit(R5C_LOG_CRITICAL, &conf->cache_state); + else + clear_bit(R5C_LOG_CRITICAL, &conf->cache_state); + if (free_space < 3 * reclaim_space) + set_bit(R5C_LOG_TIGHT, &conf->cache_state); + else + clear_bit(R5C_LOG_TIGHT, &conf->cache_state); +} + /* * Put the stripe into writing-out phase by clearing STRIPE_R5C_CACHING. * This function should only be called in write-back mode. */ -static void r5c_make_stripe_write_out(struct stripe_head *sh) +void r5c_make_stripe_write_out(struct stripe_head *sh) { struct r5conf *conf = sh->raid_conf; struct r5l_log *log = conf->log; @@ -440,6 +553,7 @@ static void r5_reserve_log_entry(struct r5l_log *log, struct r5l_io_unit *io) { log->log_start = r5l_ring_add(log, log->log_start, BLOCK_SECTORS); + r5c_update_log_state(log); /* * If we filled up the log device start from the beginning again, * which will require a new bio. @@ -600,21 +714,43 @@ static int r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh, atomic_inc(&io->pending_stripe); sh->log_io = io; + if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) + return 0; + + if (sh->log_start == MaxSector) { + BUG_ON(!list_empty(&sh->r5c)); + sh->log_start = io->log_start; + spin_lock_irq(&log->stripe_in_journal_lock); + list_add_tail(&sh->r5c, + &log->stripe_in_journal_list); + spin_unlock_irq(&log->stripe_in_journal_lock); + atomic_inc(&log->stripe_in_journal_count); + } return 0; } -static void r5l_wake_reclaim(struct r5l_log *log, sector_t space); +/* add stripe to no_space_stripes, and then wake up reclaim */ +static inline void r5l_add_no_space_stripe(struct r5l_log *log, + struct stripe_head *sh) +{ + spin_lock(&log->no_space_stripes_lock); + list_add_tail(&sh->log_list, &log->no_space_stripes); + spin_unlock(&log->no_space_stripes_lock); +} + /* * running in raid5d, where reclaim could wait for raid5d too (when it flushes * data from log to raid disks), so we shouldn't wait for reclaim here */ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh) { + struct r5conf *conf = sh->raid_conf; int write_disks = 0; int data_pages, parity_pages; int reserve; int i; int ret = 0; + bool wake_reclaim = false; if (!log) return -EAGAIN; @@ -658,22 +794,49 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh) mutex_lock(&log->io_mutex); /* meta + data */ reserve = (1 + write_disks) << (PAGE_SHIFT - 9); - if (!r5l_has_free_space(log, reserve)) { - spin_lock(&log->no_space_stripes_lock); - list_add_tail(&sh->log_list, &log->no_space_stripes); - spin_unlock(&log->no_space_stripes_lock); - r5l_wake_reclaim(log, reserve); - } else { - ret = r5l_log_stripe(log, sh, data_pages, parity_pages); - if (ret) { - spin_lock_irq(&log->io_list_lock); - list_add_tail(&sh->log_list, &log->no_mem_stripes); - spin_unlock_irq(&log->io_list_lock); + if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) { + if (!r5l_has_free_space(log, reserve)) { + r5l_add_no_space_stripe(log, sh); + wake_reclaim = true; + } else { + ret = r5l_log_stripe(log, sh, data_pages, parity_pages); + if (ret) { + spin_lock_irq(&log->io_list_lock); + list_add_tail(&sh->log_list, + &log->no_mem_stripes); + spin_unlock_irq(&log->io_list_lock); + } + } + } else { /* R5C_JOURNAL_MODE_WRITE_BACK */ + /* + * log space critical, do not process stripes that are + * not in cache yet (sh->log_start == MaxSector). + */ + if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) && + sh->log_start == MaxSector) { + r5l_add_no_space_stripe(log, sh); + wake_reclaim = true; + reserve = 0; + } else if (!r5l_has_free_space(log, reserve)) { + if (sh->log_start == log->last_checkpoint) + BUG(); + else + r5l_add_no_space_stripe(log, sh); + } else { + ret = r5l_log_stripe(log, sh, data_pages, parity_pages); + if (ret) { + spin_lock_irq(&log->io_list_lock); + list_add_tail(&sh->log_list, + &log->no_mem_stripes); + spin_unlock_irq(&log->io_list_lock); + } } } mutex_unlock(&log->io_mutex); + if (wake_reclaim) + r5l_wake_reclaim(log, reserve); return 0; } @@ -720,10 +883,40 @@ static void r5l_run_no_space_stripes(struct r5l_log *log) spin_unlock(&log->no_space_stripes_lock); } +/* + * calculate new last_checkpoint + * for write through mode, returns log->next_checkpoint + * for write back, returns log_start of first sh in stripe_in_journal_list + */ +static sector_t r5c_calculate_new_cp(struct r5conf *conf) +{ + struct stripe_head *sh; + struct r5l_log *log = conf->log; + sector_t new_cp; + unsigned long flags; + + if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) + return log->next_checkpoint; + + spin_lock_irqsave(&log->stripe_in_journal_lock, flags); + if (list_empty(&conf->log->stripe_in_journal_list)) { + /* all stripes flushed */ + spin_unlock(&log->stripe_in_journal_lock); + return log->next_checkpoint; + } + sh = list_first_entry(&conf->log->stripe_in_journal_list, + struct stripe_head, r5c); + new_cp = sh->log_start; + spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags); + return new_cp; +} + static sector_t r5l_reclaimable_space(struct r5l_log *log) { + struct r5conf *conf = log->rdev->mddev->private; + return r5l_ring_distance(log, log->last_checkpoint, - log->next_checkpoint); + r5c_calculate_new_cp(conf)); } static void r5l_run_no_mem_stripe(struct r5l_log *log) @@ -769,6 +962,7 @@ static bool r5l_complete_finished_ios(struct r5l_log *log) static void __r5l_stripe_write_finished(struct r5l_io_unit *io) { struct r5l_log *log = io->log; + struct r5conf *conf = log->rdev->mddev->private; unsigned long flags; spin_lock_irqsave(&log->io_list_lock, flags); @@ -779,7 +973,8 @@ static void __r5l_stripe_write_finished(struct r5l_io_unit *io) return; } - if (r5l_reclaimable_space(log) > log->max_free_space) + if (r5l_reclaimable_space(log) > log->max_free_space || + test_bit(R5C_LOG_TIGHT, &conf->cache_state)) r5l_wake_reclaim(log, 0); spin_unlock_irqrestore(&log->io_list_lock, flags); @@ -900,14 +1095,146 @@ static void r5l_write_super_and_discard_space(struct r5l_log *log, } } +/* + * r5c_flush_stripe moves stripe from cached list to handle_list. When called, + * the stripe must be on r5c_cached_full_stripes or r5c_cached_partial_stripes. + * + * must hold conf->device_lock + */ +static void r5c_flush_stripe(struct r5conf *conf, struct stripe_head *sh) +{ + BUG_ON(list_empty(&sh->lru)); + BUG_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state)); + BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); + + /* + * The stripe is not ON_RELEASE_LIST, so it is safe to call + * raid5_release_stripe() while holding conf->device_lock + */ + BUG_ON(test_bit(STRIPE_ON_RELEASE_LIST, &sh->state)); + assert_spin_locked(&conf->device_lock); + + list_del_init(&sh->lru); + atomic_inc(&sh->count); + + set_bit(STRIPE_HANDLE, &sh->state); + atomic_inc(&conf->active_stripes); + r5c_make_stripe_write_out(sh); + + if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) + atomic_inc(&conf->preread_active_stripes); + raid5_release_stripe(sh); +} + +/* + * if num == 0, flush all full stripes + * if num > 0, flush all full stripes. If less than num full stripes are + * flushed, flush some partial stripes until totally num stripes are + * flushed or there is no more cached stripes. + */ +void r5c_flush_cache(struct r5conf *conf, int num) +{ + int count; + struct stripe_head *sh, *next; + + assert_spin_locked(&conf->device_lock); + if (!conf->log) + return; + + count = 0; + list_for_each_entry_safe(sh, next, &conf->r5c_full_stripe_list, lru) { + r5c_flush_stripe(conf, sh); + count++; + } + + if (count >= num) + return; + list_for_each_entry_safe(sh, next, + &conf->r5c_partial_stripe_list, lru) { + r5c_flush_stripe(conf, sh); + if (++count >= num) + break; + } +} + +static void r5c_do_reclaim(struct r5conf *conf) +{ + struct r5l_log *log = conf->log; + struct stripe_head *sh; + int count = 0; + unsigned long flags; + int total_cached; + int stripes_to_flush; + + if (!r5c_is_writeback(log)) + return; + + total_cached = atomic_read(&conf->r5c_cached_partial_stripes) + + atomic_read(&conf->r5c_cached_full_stripes); + + if (total_cached > conf->min_nr_stripes * 3 / 4 || + atomic_read(&conf->empty_inactive_list_nr) > 0) + /* + * if stripe cache pressure high, flush all full stripes and + * some partial stripes + */ + stripes_to_flush = R5C_RECLAIM_STRIPE_GROUP; + else if (total_cached > conf->min_nr_stripes * 1 / 2 || + atomic_read(&conf->r5c_cached_full_stripes) > + R5C_FULL_STRIPE_FLUSH_BATCH) + /* + * if stripe cache pressure moderate, or if there is many full + * stripes,flush all full stripes + */ + stripes_to_flush = 0; + else + /* no need to flush */ + stripes_to_flush = -1; + + if (stripes_to_flush >= 0) { + spin_lock_irqsave(&conf->device_lock, flags); + r5c_flush_cache(conf, stripes_to_flush); + spin_unlock_irqrestore(&conf->device_lock, flags); + } + + /* if log space is tight, flush stripes on stripe_in_journal_list */ + if (test_bit(R5C_LOG_TIGHT, &conf->cache_state)) { + spin_lock_irqsave(&log->stripe_in_journal_lock, flags); + spin_lock(&conf->device_lock); + list_for_each_entry(sh, &log->stripe_in_journal_list, r5c) { + /* + * stripes on stripe_in_journal_list could be in any + * state of the stripe_cache state machine. In this + * case, we only want to flush stripe on + * r5c_cached_full/partial_stripes. The following + * condition makes sure the stripe is on one of the + * two lists. + */ + if (!list_empty(&sh->lru) && + !test_bit(STRIPE_HANDLE, &sh->state) && + atomic_read(&sh->count) == 0) { + r5c_flush_stripe(conf, sh); + } + if (count++ >= R5C_RECLAIM_STRIPE_GROUP) + break; + } + spin_unlock(&conf->device_lock); + spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags); + } + md_wakeup_thread(conf->mddev->thread); +} + static void r5l_do_reclaim(struct r5l_log *log) { + struct r5conf *conf = log->rdev->mddev->private; sector_t reclaim_target = xchg(&log->reclaim_target, 0); sector_t reclaimable; sector_t next_checkpoint; - u64 next_cp_seq; + bool write_super; spin_lock_irq(&log->io_list_lock); + write_super = r5l_reclaimable_space(log) > log->max_free_space || + reclaim_target != 0 || !list_empty(&log->no_space_stripes); /* * move proper io_unit to reclaim list. We should not change the order. * reclaimable/unreclaimable io_unit can be mixed in the list, we @@ -928,12 +1255,12 @@ static void r5l_do_reclaim(struct r5l_log *log) log->io_list_lock); } - next_checkpoint = log->next_checkpoint; - next_cp_seq = log->next_cp_seq; + next_checkpoint = r5c_calculate_new_cp(conf); spin_unlock_irq(&log->io_list_lock); BUG_ON(reclaimable < 0); - if (reclaimable == 0) + + if (reclaimable == 0 || !write_super) return; /* @@ -945,7 +1272,7 @@ static void r5l_do_reclaim(struct r5l_log *log) mutex_lock(&log->io_mutex); log->last_checkpoint = next_checkpoint; - log->last_cp_seq = next_cp_seq; + r5c_update_log_state(log); mutex_unlock(&log->io_mutex); r5l_run_no_space_stripes(log); @@ -959,14 +1286,17 @@ static void r5l_reclaim_thread(struct md_thread *thread) if (!log) return; + r5c_do_reclaim(conf); r5l_do_reclaim(log); } -static void r5l_wake_reclaim(struct r5l_log *log, sector_t space) +void r5l_wake_reclaim(struct r5l_log *log, sector_t space) { unsigned long target; unsigned long new = (unsigned long)space; /* overflow in theory */ + if (!log) + return; do { target = log->reclaim_target; if (new < target) @@ -990,11 +1320,12 @@ void r5l_quiesce(struct r5l_log *log, int state) return; log->reclaim_thread = md_register_thread(r5l_reclaim_thread, log->rdev->mddev, "reclaim"); + log->reclaim_thread->timeout = R5C_RECLAIM_WAKEUP_INTERVAL; } else if (state == 1) { /* make sure r5l_write_super_and_discard_space exits */ mddev = log->rdev->mddev; wake_up(&mddev->sb_wait); - r5l_wake_reclaim(log, -1L); + r5l_wake_reclaim(log, MaxSector); md_unregister_thread(&log->reclaim_thread); r5l_do_reclaim(log); } @@ -1415,12 +1746,22 @@ void r5c_finish_stripe_write_out(struct r5conf *conf, if (do_wakeup) wake_up(&conf->wait_for_overlap); + + if (conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) + return; + + spin_lock_irq(&conf->log->stripe_in_journal_lock); + list_del_init(&sh->r5c); + spin_unlock_irq(&conf->log->stripe_in_journal_lock); + sh->log_start = MaxSector; + atomic_dec(&conf->log->stripe_in_journal_count); } int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh, struct stripe_head_state *s) { + struct r5conf *conf = sh->raid_conf; int pages = 0; int reserve; int i; @@ -1451,12 +1792,15 @@ r5c_cache_data(struct r5l_log *log, struct stripe_head *sh, mutex_lock(&log->io_mutex); /* meta + data */ reserve = (1 + pages) << (PAGE_SHIFT - 9); - if (!r5l_has_free_space(log, reserve)) { - spin_lock(&log->no_space_stripes_lock); - list_add_tail(&sh->log_list, &log->no_space_stripes); - spin_unlock(&log->no_space_stripes_lock); - r5l_wake_reclaim(log, reserve); + if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) && + sh->log_start == MaxSector) + r5l_add_no_space_stripe(log, sh); + else if (!r5l_has_free_space(log, reserve)) { + if (sh->log_start == log->last_checkpoint) + BUG(); + else + r5l_add_no_space_stripe(log, sh); } else { ret = r5l_log_stripe(log, sh, pages, 0); if (ret) { @@ -1470,7 +1814,6 @@ r5c_cache_data(struct r5l_log *log, struct stripe_head *sh, return 0; } - static int r5l_load_log(struct r5l_log *log) { struct md_rdev *rdev = log->rdev; @@ -1530,6 +1873,9 @@ create: log->max_free_space = RECLAIM_MAX_FREE_SPACE; log->last_checkpoint = cp; log->next_checkpoint = cp; + mutex_lock(&log->io_mutex); + r5c_update_log_state(log); + mutex_unlock(&log->io_mutex); __free_page(page); @@ -1601,6 +1947,8 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev) log->rdev->mddev, "reclaim"); if (!log->reclaim_thread) goto reclaim_thread; + log->reclaim_thread->timeout = R5C_RECLAIM_WAKEUP_INTERVAL; + init_waitqueue_head(&log->iounit_wait); INIT_LIST_HEAD(&log->no_mem_stripes); @@ -1609,6 +1957,9 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev) spin_lock_init(&log->no_space_stripes_lock); log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH; + INIT_LIST_HEAD(&log->stripe_in_journal_list); + spin_lock_init(&log->stripe_in_journal_lock); + atomic_set(&log->stripe_in_journal_count, 0); if (r5l_load_log(log)) goto error; diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index f535ce2c267a..90638ba67812 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -228,6 +228,16 @@ static void do_release_stripe(struct r5conf *conf, struct stripe_head *sh, for (i = sh->disks; i--; ) if (test_bit(R5_InJournal, &sh->dev[i].flags)) injournal++; + /* + * When quiesce in r5c write back, set STRIPE_HANDLE for stripes with + * data in journal, so they are not released to cached lists + */ + if (conf->quiesce && r5c_is_writeback(conf->log) && + !test_bit(STRIPE_HANDLE, &sh->state) && injournal != 0) { + if (test_bit(STRIPE_R5C_CACHING, &sh->state)) + r5c_make_stripe_write_out(sh); + set_bit(STRIPE_HANDLE, &sh->state); + } if (test_bit(STRIPE_HANDLE, &sh->state)) { if (test_bit(STRIPE_DELAYED, &sh->state) && @@ -268,6 +278,7 @@ static void do_release_stripe(struct r5conf *conf, struct stripe_head *sh, if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) atomic_dec(&conf->r5c_cached_partial_stripes); list_add_tail(&sh->lru, &conf->r5c_full_stripe_list); + r5c_check_cached_full_stripe(conf); } else { /* partial stripe */ if (!test_and_set_bit(STRIPE_R5C_PARTIAL_STRIPE, @@ -639,9 +650,12 @@ raid5_get_active_stripe(struct r5conf *conf, sector_t sector, } if (noblock && sh == NULL) break; + + r5c_check_stripe_cache_usage(conf); if (!sh) { set_bit(R5_INACTIVE_BLOCKED, &conf->cache_state); + r5l_wake_reclaim(conf->log, 0); wait_event_lock_irq( conf->wait_for_stripe, !list_empty(conf->inactive_list + hash) && @@ -1992,7 +2006,9 @@ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp, spin_lock_init(&sh->batch_lock); INIT_LIST_HEAD(&sh->batch_list); INIT_LIST_HEAD(&sh->lru); + INIT_LIST_HEAD(&sh->r5c); atomic_set(&sh->count, 1); + sh->log_start = MaxSector; for (i = 0; i < disks; i++) { struct r5dev *dev = &sh->dev[i]; @@ -4759,6 +4775,10 @@ static int raid5_congested(struct mddev *mddev, int bits) if (test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state)) return 1; + + /* Also checks whether there is pressure on r5cache log space */ + if (test_bit(R5C_LOG_TIGHT, &conf->cache_state)) + return 1; if (conf->quiesce) return 1; if (atomic_read(&conf->empty_inactive_list_nr)) @@ -7661,6 +7681,7 @@ static void raid5_quiesce(struct mddev *mddev, int state) /* '2' tells resync/reshape to pause so that all * active stripes can drain */ + r5c_flush_cache(conf, INT_MAX); conf->quiesce = 2; wait_event_cmd(conf->wait_for_quiescent, atomic_read(&conf->active_stripes) == 0 && diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 73c183398e38..35b4c0f0a850 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -226,6 +226,8 @@ struct stripe_head { struct r5l_io_unit *log_io; struct list_head log_list; + sector_t log_start; /* first meta block on the journal */ + struct list_head r5c; /* for r5c_cache->stripe_in_journal */ /** * struct stripe_operations * @target - STRIPE_OP_COMPUTE_BLK target @@ -537,6 +539,27 @@ struct r5worker_group { int stripes_cnt; }; +enum r5_cache_state { + R5_INACTIVE_BLOCKED, /* release of inactive stripes blocked, + * waiting for 25% to be free + */ + R5_ALLOC_MORE, /* It might help to allocate another + * stripe. + */ + R5_DID_ALLOC, /* A stripe was allocated, don't allocate + * more until at least one has been + * released. This avoids flooding + * the cache. + */ + R5C_LOG_TIGHT, /* log device space tight, need to + * prioritize stripes at last_checkpoint + */ + R5C_LOG_CRITICAL, /* log device is running out of space, + * only process stripes that are already + * occupying the log + */ +}; + struct r5conf { struct hlist_head *stripe_hashtbl; /* only protect corresponding hash list and inactive_list */ @@ -636,17 +659,6 @@ struct r5conf { wait_queue_head_t wait_for_stripe; wait_queue_head_t wait_for_overlap; unsigned long cache_state; -#define R5_INACTIVE_BLOCKED 1 /* release of inactive stripes blocked, - * waiting for 25% to be free - */ -#define R5_ALLOC_MORE 2 /* It might help to allocate another - * stripe. - */ -#define R5_DID_ALLOC 4 /* A stripe was allocated, don't allocate - * more until at least one has been - * released. This avoids flooding - * the cache. - */ struct shrinker shrinker; int pool_size; /* number of disks in stripeheads in pool */ spinlock_t device_lock; @@ -752,8 +764,13 @@ extern void r5c_finish_stripe_write_out(struct r5conf *conf, struct stripe_head *sh, struct stripe_head_state *s); extern void r5c_release_extra_page(struct stripe_head *sh); +extern void r5l_wake_reclaim(struct r5l_log *log, sector_t space); extern void r5c_handle_cached_data_endio(struct r5conf *conf, struct stripe_head *sh, int disks, struct bio_list *return_bi); extern int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh, struct stripe_head_state *s); +extern void r5c_make_stripe_write_out(struct stripe_head *sh); +extern void r5c_flush_cache(struct r5conf *conf, int num); +extern void r5c_check_stripe_cache_usage(struct r5conf *conf); +extern void r5c_check_cached_full_stripe(struct r5conf *conf); #endif |