diff options
Diffstat (limited to 'fs/btrfs/discard.c')
| -rw-r--r-- | fs/btrfs/discard.c | 55 |
1 files changed, 51 insertions, 4 deletions
diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c index 62298a438fa5..29645676427b 100644 --- a/fs/btrfs/discard.c +++ b/fs/btrfs/discard.c @@ -15,6 +15,12 @@ #define BTRFS_DISCARD_DELAY (120ULL * NSEC_PER_SEC) #define BTRFS_DISCARD_UNUSED_DELAY (10ULL * NSEC_PER_SEC) +/* Target completion latency of discarding all discardable extents */ +#define BTRFS_DISCARD_TARGET_MSEC (6 * 60 * 60UL * MSEC_PER_SEC) +#define BTRFS_DISCARD_MIN_DELAY_MSEC (1UL) +#define BTRFS_DISCARD_MAX_DELAY_MSEC (1000UL) +#define BTRFS_DISCARD_MAX_IOPS (10U) + static struct list_head *get_discard_list(struct btrfs_discard_ctl *discard_ctl, struct btrfs_block_group *block_group) { @@ -235,11 +241,17 @@ void btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl, block_group = find_next_block_group(discard_ctl, now); if (block_group) { - u64 delay = 0; + unsigned long delay = discard_ctl->delay; + + /* + * This timeout is to hopefully prevent immediate discarding + * in a recently allocated block group. + */ + if (now < block_group->discard_eligible_time) { + u64 bg_timeout = block_group->discard_eligible_time - now; - if (now < block_group->discard_eligible_time) - delay = nsecs_to_jiffies( - block_group->discard_eligible_time - now); + delay = max(delay, nsecs_to_jiffies(bg_timeout)); + } mod_delayed_work(discard_ctl->discard_workers, &discard_ctl->work, delay); @@ -343,6 +355,39 @@ bool btrfs_run_discard_work(struct btrfs_discard_ctl *discard_ctl) } /** + * btrfs_discard_calc_delay - recalculate the base delay + * @discard_ctl: discard control + * + * Recalculate the base delay which is based off the total number of + * discardable_extents. Clamp this between the lower_limit (iops_limit or 1ms) + * and the upper_limit (BTRFS_DISCARD_MAX_DELAY_MSEC). + */ +void btrfs_discard_calc_delay(struct btrfs_discard_ctl *discard_ctl) +{ + s32 discardable_extents; + u32 iops_limit; + unsigned long delay; + unsigned long lower_limit = BTRFS_DISCARD_MIN_DELAY_MSEC; + + discardable_extents = atomic_read(&discard_ctl->discardable_extents); + if (!discardable_extents) + return; + + spin_lock(&discard_ctl->lock); + + iops_limit = READ_ONCE(discard_ctl->iops_limit); + if (iops_limit) + lower_limit = max_t(unsigned long, lower_limit, + MSEC_PER_SEC / iops_limit); + + delay = BTRFS_DISCARD_TARGET_MSEC / discardable_extents; + delay = clamp(delay, lower_limit, BTRFS_DISCARD_MAX_DELAY_MSEC); + discard_ctl->delay = msecs_to_jiffies(delay); + + spin_unlock(&discard_ctl->lock); +} + +/** * btrfs_discard_update_discardable - propagate discard counters * @block_group: block_group of interest * @ctl: free_space_ctl of @block_group @@ -464,6 +509,8 @@ void btrfs_discard_init(struct btrfs_fs_info *fs_info) atomic_set(&discard_ctl->discardable_extents, 0); atomic64_set(&discard_ctl->discardable_bytes, 0); + discard_ctl->delay = BTRFS_DISCARD_MAX_DELAY_MSEC; + discard_ctl->iops_limit = BTRFS_DISCARD_MAX_IOPS; } void btrfs_discard_cleanup(struct btrfs_fs_info *fs_info) |