diff options
Diffstat (limited to 'fs/btrfs/discard.c')
-rw-r--r-- | fs/btrfs/discard.c | 111 |
1 files changed, 62 insertions, 49 deletions
diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c index 51f0ef386046..ff2e524d9937 100644 --- a/fs/btrfs/discard.c +++ b/fs/btrfs/discard.c @@ -62,7 +62,7 @@ #define BTRFS_DISCARD_MAX_DELAY_MSEC (1000UL) #define BTRFS_DISCARD_MAX_IOPS (10U) -/* Montonically decreasing minimum length filters after index 0 */ +/* Monotonically decreasing minimum length filters after index 0 */ static int discard_minlen[BTRFS_NR_DISCARD_LISTS] = { 0, BTRFS_ASYNC_DISCARD_MAX_FILTER, @@ -147,10 +147,11 @@ static bool remove_from_discard_list(struct btrfs_discard_ctl *discard_ctl, return running; } -/** - * find_next_block_group - find block_group that's up next for discarding - * @discard_ctl: discard control - * @now: current time +/* + * Find block_group that's up next for discarding. + * + * @discard_ctl: discard control + * @now: current time * * Iterate over the discard lists to find the next block_group up for * discarding checking the discard_eligible_time of block_group. @@ -185,17 +186,17 @@ static struct btrfs_block_group *find_next_block_group( return ret_block_group; } -/** - * Wrap find_next_block_group() +/* + * Look up next block group and set it for use. * * @discard_ctl: discard control * @discard_state: the discard_state of the block_group after state management * @discard_index: the discard_index of the block_group after state management * @now: time when discard was invoked, in ns * - * This wraps find_next_block_group() and sets the block_group to be in use. - * discard_state's control flow is managed here. Variables related to - * discard_state are reset here as needed (eg discard_cursor). @discard_state + * Wrap find_next_block_group() and set the block_group to be in use. + * @discard_state's control flow is managed here. Variables related to + * @discard_state are reset here as needed (eg. @discard_cursor). @discard_state * and @discard_index are remembered as it may change while we're discarding, * but we want the discard to execute in the context determined here. */ @@ -234,10 +235,11 @@ again: return block_group; } -/** - * btrfs_discard_check_filter - updates a block groups filters - * @block_group: block group of interest - * @bytes: recently freed region size after coalescing +/* + * Update a block group's filters. + * + * @block_group: block group of interest + * @bytes: recently freed region size after coalescing * * Async discard maintains multiple lists with progressively smaller filters * to prioritize discarding based on size. Should a free space that matches @@ -272,8 +274,9 @@ void btrfs_discard_check_filter(struct btrfs_block_group *block_group, } } -/** - * btrfs_update_discard_index - moves a block group along the discard lists +/* + * Move a block group along the discard lists. + * * @discard_ctl: discard control * @block_group: block_group of interest * @@ -292,13 +295,14 @@ static void btrfs_update_discard_index(struct btrfs_discard_ctl *discard_ctl, add_to_discard_list(discard_ctl, block_group); } -/** - * btrfs_discard_cancel_work - remove a block_group from the discard lists +/* + * Remove a block_group from the discard lists. + * * @discard_ctl: discard control * @block_group: block_group of interest * - * This removes @block_group from the discard lists. If necessary, it waits on - * the current work and then reschedules the delayed work. + * Remove @block_group from the discard lists. If necessary, wait on the + * current work and then reschedule the delayed work. */ void btrfs_discard_cancel_work(struct btrfs_discard_ctl *discard_ctl, struct btrfs_block_group *block_group) @@ -309,12 +313,13 @@ void btrfs_discard_cancel_work(struct btrfs_discard_ctl *discard_ctl, } } -/** - * btrfs_discard_queue_work - handles queuing the block_groups +/* + * Handles queuing the block_groups. + * * @discard_ctl: discard control * @block_group: block_group of interest * - * This maintains the LRU order of the discard lists. + * Maintain the LRU order of the discard lists. */ void btrfs_discard_queue_work(struct btrfs_discard_ctl *discard_ctl, struct btrfs_block_group *block_group) @@ -384,7 +389,8 @@ static void __btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl, } /* - * btrfs_discard_schedule_work - responsible for scheduling the discard work + * Responsible for scheduling the discard work. + * * @discard_ctl: discard control * @override: override the current timer * @@ -402,15 +408,16 @@ void btrfs_discard_schedule_work(struct btrfs_discard_ctl *discard_ctl, spin_unlock(&discard_ctl->lock); } -/** - * btrfs_finish_discard_pass - determine next step of a block_group +/* + * Determine next step of a block_group. + * * @discard_ctl: discard control * @block_group: block_group of interest * - * This determines the next step for a block group after it's finished going - * through a pass on a discard list. If it is unused and fully trimmed, we can - * mark it unused and send it to the unused_bgs path. Otherwise, pass it onto - * the appropriate filter list or let it fall off. + * Determine the next step for a block group after it's finished going through + * a pass on a discard list. If it is unused and fully trimmed, we can mark it + * unused and send it to the unused_bgs path. Otherwise, pass it onto the + * appropriate filter list or let it fall off. */ static void btrfs_finish_discard_pass(struct btrfs_discard_ctl *discard_ctl, struct btrfs_block_group *block_group) @@ -427,12 +434,13 @@ static void btrfs_finish_discard_pass(struct btrfs_discard_ctl *discard_ctl, } } -/** - * btrfs_discard_workfn - discard work function +/* + * Discard work queue callback + * * @work: work * - * This finds the next block_group to start discarding and then discards a - * single region. It does this in a two-pass fashion: first extents and second + * Find the next block_group to start discarding and then discard a single + * region. It does this in a two-pass fashion: first extents and second * bitmaps. Completely discarded block groups are sent to the unused_bgs path. */ static void btrfs_discard_workfn(struct work_struct *work) @@ -508,11 +516,12 @@ static void btrfs_discard_workfn(struct work_struct *work) spin_unlock(&discard_ctl->lock); } -/** - * btrfs_run_discard_work - determines if async discard should be running +/* + * Determine if async discard should be running. + * * @discard_ctl: discard control * - * Checks if the file system is writeable and BTRFS_FS_DISCARD_RUNNING is set. + * Check if the file system is writeable and BTRFS_FS_DISCARD_RUNNING is set. */ bool btrfs_run_discard_work(struct btrfs_discard_ctl *discard_ctl) { @@ -524,8 +533,9 @@ bool btrfs_run_discard_work(struct btrfs_discard_ctl *discard_ctl) test_bit(BTRFS_FS_DISCARD_RUNNING, &fs_info->flags)); } -/** - * btrfs_discard_calc_delay - recalculate the base delay +/* + * Recalculate the base delay. + * * @discard_ctl: discard control * * Recalculate the base delay which is based off the total number of @@ -546,7 +556,7 @@ void btrfs_discard_calc_delay(struct btrfs_discard_ctl *discard_ctl) spin_lock(&discard_ctl->lock); /* - * The following is to fix a potential -1 discrepenancy that we're not + * The following is to fix a potential -1 discrepancy that we're not * sure how to reproduce. But given that this is the only place that * utilizes these numbers and this is only called by from * btrfs_finish_extent_commit() which is synchronized, we can correct @@ -579,13 +589,14 @@ void btrfs_discard_calc_delay(struct btrfs_discard_ctl *discard_ctl) spin_unlock(&discard_ctl->lock); } -/** - * btrfs_discard_update_discardable - propagate discard counters +/* + * Propagate discard counters. + * * @block_group: block_group of interest * - * This propagates deltas of counters up to the discard_ctl. It maintains a - * current counter and a previous counter passing the delta up to the global - * stat. Then the current counter value becomes the previous counter value. + * Propagate deltas of counters up to the discard_ctl. It maintains a current + * counter and a previous counter passing the delta up to the global stat. + * Then the current counter value becomes the previous counter value. */ void btrfs_discard_update_discardable(struct btrfs_block_group *block_group) { @@ -620,8 +631,9 @@ void btrfs_discard_update_discardable(struct btrfs_block_group *block_group) } } -/** - * btrfs_discard_punt_unused_bgs_list - punt unused_bgs list to discard lists +/* + * Punt unused_bgs list to discard lists. + * * @fs_info: fs_info of interest * * The unused_bgs list needs to be punted to the discard lists because the @@ -645,8 +657,9 @@ void btrfs_discard_punt_unused_bgs_list(struct btrfs_fs_info *fs_info) spin_unlock(&fs_info->unused_bgs_lock); } -/** - * btrfs_discard_purge_list - purge discard lists +/* + * Purge discard lists. + * * @discard_ctl: discard control * * If we are disabling async discard, we may have intercepted block groups that |