diff options
Diffstat (limited to 'c_src/libbcachefs/movinggc.c')
-rw-r--r-- | c_src/libbcachefs/movinggc.c | 436 |
1 files changed, 0 insertions, 436 deletions
diff --git a/c_src/libbcachefs/movinggc.c b/c_src/libbcachefs/movinggc.c deleted file mode 100644 index 69e06a84..00000000 --- a/c_src/libbcachefs/movinggc.c +++ /dev/null @@ -1,436 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Moving/copying garbage collector - * - * Copyright 2012 Google, Inc. - */ - -#include "bcachefs.h" -#include "alloc_background.h" -#include "alloc_foreground.h" -#include "btree_iter.h" -#include "btree_update.h" -#include "btree_write_buffer.h" -#include "buckets.h" -#include "clock.h" -#include "errcode.h" -#include "error.h" -#include "lru.h" -#include "move.h" -#include "movinggc.h" -#include "trace.h" - -#include <linux/freezer.h> -#include <linux/kthread.h> -#include <linux/math64.h> -#include <linux/sched/task.h> -#include <linux/wait.h> - -struct buckets_in_flight { - struct rhashtable table; - struct move_bucket_in_flight *first; - struct move_bucket_in_flight *last; - size_t nr; - size_t sectors; -}; - -static const struct rhashtable_params bch_move_bucket_params = { - .head_offset = offsetof(struct move_bucket_in_flight, hash), - .key_offset = offsetof(struct move_bucket_in_flight, bucket.k), - .key_len = sizeof(struct move_bucket_key), -}; - -static struct move_bucket_in_flight * -move_bucket_in_flight_add(struct buckets_in_flight *list, struct move_bucket b) -{ - struct move_bucket_in_flight *new = kzalloc(sizeof(*new), GFP_KERNEL); - int ret; - - if (!new) - return ERR_PTR(-ENOMEM); - - new->bucket = b; - - ret = rhashtable_lookup_insert_fast(&list->table, &new->hash, - bch_move_bucket_params); - if (ret) { - kfree(new); - return ERR_PTR(ret); - } - - if (!list->first) - list->first = new; - else - list->last->next = new; - - list->last = new; - list->nr++; - list->sectors += b.sectors; - return new; -} - -static int bch2_bucket_is_movable(struct btree_trans *trans, - struct move_bucket *b, u64 time) -{ - struct btree_iter iter; - struct bkey_s_c k; - struct bch_alloc_v4 _a; - const struct bch_alloc_v4 *a; - int ret; - - if (bch2_bucket_is_open(trans->c, - b->k.bucket.inode, - b->k.bucket.offset)) - return 0; - - k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_alloc, - b->k.bucket, BTREE_ITER_CACHED); - ret = bkey_err(k); - if (ret) - return ret; - - a = bch2_alloc_to_v4(k, &_a); - b->k.gen = a->gen; - b->sectors = bch2_bucket_sectors_dirty(*a); - - ret = data_type_movable(a->data_type) && - a->fragmentation_lru && - a->fragmentation_lru <= time; - - bch2_trans_iter_exit(trans, &iter); - return ret; -} - -static void move_buckets_wait(struct moving_context *ctxt, - struct buckets_in_flight *list, - bool flush) -{ - struct move_bucket_in_flight *i; - int ret; - - while ((i = list->first)) { - if (flush) - move_ctxt_wait_event(ctxt, !atomic_read(&i->count)); - - if (atomic_read(&i->count)) - break; - - list->first = i->next; - if (!list->first) - list->last = NULL; - - list->nr--; - list->sectors -= i->bucket.sectors; - - ret = rhashtable_remove_fast(&list->table, &i->hash, - bch_move_bucket_params); - BUG_ON(ret); - kfree(i); - } - - bch2_trans_unlock_long(ctxt->trans); -} - -static bool bucket_in_flight(struct buckets_in_flight *list, - struct move_bucket_key k) -{ - return rhashtable_lookup_fast(&list->table, &k, bch_move_bucket_params); -} - -typedef DARRAY(struct move_bucket) move_buckets; - -static int bch2_copygc_get_buckets(struct moving_context *ctxt, - struct buckets_in_flight *buckets_in_flight, - move_buckets *buckets) -{ - struct btree_trans *trans = ctxt->trans; - struct bch_fs *c = trans->c; - size_t nr_to_get = max_t(size_t, 16U, buckets_in_flight->nr / 4); - size_t saw = 0, in_flight = 0, not_movable = 0, sectors = 0; - int ret; - - move_buckets_wait(ctxt, buckets_in_flight, false); - - ret = bch2_btree_write_buffer_tryflush(trans); - if (bch2_err_matches(ret, EROFS)) - return ret; - - if (bch2_fs_fatal_err_on(ret, c, "%s: error %s from bch2_btree_write_buffer_tryflush()", - __func__, bch2_err_str(ret))) - return ret; - - ret = for_each_btree_key_upto(trans, iter, BTREE_ID_lru, - lru_pos(BCH_LRU_FRAGMENTATION_START, 0, 0), - lru_pos(BCH_LRU_FRAGMENTATION_START, U64_MAX, LRU_TIME_MAX), - 0, k, ({ - struct move_bucket b = { .k.bucket = u64_to_bucket(k.k->p.offset) }; - int ret2 = 0; - - saw++; - - ret2 = bch2_bucket_is_movable(trans, &b, lru_pos_time(k.k->p)); - if (ret2 < 0) - goto err; - - if (!ret2) - not_movable++; - else if (bucket_in_flight(buckets_in_flight, b.k)) - in_flight++; - else { - ret2 = darray_push(buckets, b); - if (ret2) - goto err; - sectors += b.sectors; - } - - ret2 = buckets->nr >= nr_to_get; -err: - ret2; - })); - - pr_debug("have: %zu (%zu) saw %zu in flight %zu not movable %zu got %zu (%zu)/%zu buckets ret %i", - buckets_in_flight->nr, buckets_in_flight->sectors, - saw, in_flight, not_movable, buckets->nr, sectors, nr_to_get, ret); - - return ret < 0 ? ret : 0; -} - -noinline -static int bch2_copygc(struct moving_context *ctxt, - struct buckets_in_flight *buckets_in_flight, - bool *did_work) -{ - struct btree_trans *trans = ctxt->trans; - struct bch_fs *c = trans->c; - struct data_update_opts data_opts = { - .btree_insert_flags = BCH_WATERMARK_copygc, - }; - move_buckets buckets = { 0 }; - struct move_bucket_in_flight *f; - u64 moved = atomic64_read(&ctxt->stats->sectors_moved); - int ret = 0; - - ret = bch2_copygc_get_buckets(ctxt, buckets_in_flight, &buckets); - if (ret) - goto err; - - darray_for_each(buckets, i) { - if (kthread_should_stop() || freezing(current)) - break; - - f = move_bucket_in_flight_add(buckets_in_flight, *i); - ret = PTR_ERR_OR_ZERO(f); - if (ret == -EEXIST) { /* rare race: copygc_get_buckets returned same bucket more than once */ - ret = 0; - continue; - } - if (ret == -ENOMEM) { /* flush IO, continue later */ - ret = 0; - break; - } - - ret = bch2_evacuate_bucket(ctxt, f, f->bucket.k.bucket, - f->bucket.k.gen, data_opts); - if (ret) - goto err; - - *did_work = true; - } -err: - darray_exit(&buckets); - - /* no entries in LRU btree found, or got to end: */ - if (bch2_err_matches(ret, ENOENT)) - ret = 0; - - if (ret < 0 && !bch2_err_matches(ret, EROFS)) - bch_err_msg(c, ret, "from bch2_move_data()"); - - moved = atomic64_read(&ctxt->stats->sectors_moved) - moved; - trace_and_count(c, copygc, c, moved, 0, 0, 0); - return ret; -} - -/* - * Copygc runs when the amount of fragmented data is above some arbitrary - * threshold: - * - * The threshold at the limit - when the device is full - is the amount of space - * we reserved in bch2_recalc_capacity; we can't have more than that amount of - * disk space stranded due to fragmentation and store everything we have - * promised to store. - * - * But we don't want to be running copygc unnecessarily when the device still - * has plenty of free space - rather, we want copygc to smoothly run every so - * often and continually reduce the amount of fragmented space as the device - * fills up. So, we increase the threshold by half the current free space. - */ -unsigned long bch2_copygc_wait_amount(struct bch_fs *c) -{ - s64 wait = S64_MAX, fragmented_allowed, fragmented; - - for_each_rw_member(c, ca) { - struct bch_dev_usage usage = bch2_dev_usage_read(ca); - - fragmented_allowed = ((__dev_buckets_available(ca, usage, BCH_WATERMARK_stripe) * - ca->mi.bucket_size) >> 1); - fragmented = 0; - - for (unsigned i = 0; i < BCH_DATA_NR; i++) - if (data_type_movable(i)) - fragmented += usage.d[i].fragmented; - - wait = min(wait, max(0LL, fragmented_allowed - fragmented)); - } - - return wait; -} - -void bch2_copygc_wait_to_text(struct printbuf *out, struct bch_fs *c) -{ - prt_printf(out, "Currently waiting for: "); - prt_human_readable_u64(out, max(0LL, c->copygc_wait - - atomic64_read(&c->io_clock[WRITE].now)) << 9); - prt_newline(out); - - prt_printf(out, "Currently waiting since: "); - prt_human_readable_u64(out, max(0LL, - atomic64_read(&c->io_clock[WRITE].now) - - c->copygc_wait_at) << 9); - prt_newline(out); - - prt_printf(out, "Currently calculated wait: "); - prt_human_readable_u64(out, bch2_copygc_wait_amount(c)); - prt_newline(out); -} - -static int bch2_copygc_thread(void *arg) -{ - struct bch_fs *c = arg; - struct moving_context ctxt; - struct bch_move_stats move_stats; - struct io_clock *clock = &c->io_clock[WRITE]; - struct buckets_in_flight *buckets; - u64 last, wait; - int ret = 0; - - buckets = kzalloc(sizeof(struct buckets_in_flight), GFP_KERNEL); - if (!buckets) - return -ENOMEM; - ret = rhashtable_init(&buckets->table, &bch_move_bucket_params); - bch_err_msg(c, ret, "allocating copygc buckets in flight"); - if (ret) { - kfree(buckets); - return ret; - } - - set_freezable(); - - bch2_move_stats_init(&move_stats, "copygc"); - bch2_moving_ctxt_init(&ctxt, c, NULL, &move_stats, - writepoint_ptr(&c->copygc_write_point), - false); - - while (!ret && !kthread_should_stop()) { - bool did_work = false; - - bch2_trans_unlock_long(ctxt.trans); - cond_resched(); - - if (!c->copy_gc_enabled) { - move_buckets_wait(&ctxt, buckets, true); - kthread_wait_freezable(c->copy_gc_enabled || - kthread_should_stop()); - } - - if (unlikely(freezing(current))) { - move_buckets_wait(&ctxt, buckets, true); - __refrigerator(false); - continue; - } - - last = atomic64_read(&clock->now); - wait = bch2_copygc_wait_amount(c); - - if (wait > clock->max_slop) { - c->copygc_wait_at = last; - c->copygc_wait = last + wait; - move_buckets_wait(&ctxt, buckets, true); - trace_and_count(c, copygc_wait, c, wait, last + wait); - bch2_kthread_io_clock_wait(clock, last + wait, - MAX_SCHEDULE_TIMEOUT); - continue; - } - - c->copygc_wait = 0; - - c->copygc_running = true; - ret = bch2_copygc(&ctxt, buckets, &did_work); - c->copygc_running = false; - - wake_up(&c->copygc_running_wq); - - if (!wait && !did_work) { - u64 min_member_capacity = bch2_min_rw_member_capacity(c); - - if (min_member_capacity == U64_MAX) - min_member_capacity = 128 * 2048; - - bch2_trans_unlock_long(ctxt.trans); - bch2_kthread_io_clock_wait(clock, last + (min_member_capacity >> 6), - MAX_SCHEDULE_TIMEOUT); - } - } - - move_buckets_wait(&ctxt, buckets, true); - - rhashtable_destroy(&buckets->table); - kfree(buckets); - bch2_moving_ctxt_exit(&ctxt); - bch2_move_stats_exit(&move_stats, c); - - return 0; -} - -void bch2_copygc_stop(struct bch_fs *c) -{ - if (c->copygc_thread) { - kthread_stop(c->copygc_thread); - put_task_struct(c->copygc_thread); - } - c->copygc_thread = NULL; -} - -int bch2_copygc_start(struct bch_fs *c) -{ - struct task_struct *t; - int ret; - - if (c->copygc_thread) - return 0; - - if (c->opts.nochanges) - return 0; - - if (bch2_fs_init_fault("copygc_start")) - return -ENOMEM; - - t = kthread_create(bch2_copygc_thread, c, "bch-copygc/%s", c->name); - ret = PTR_ERR_OR_ZERO(t); - bch_err_msg(c, ret, "creating copygc thread"); - if (ret) - return ret; - - get_task_struct(t); - - c->copygc_thread = t; - wake_up_process(c->copygc_thread); - - return 0; -} - -void bch2_fs_copygc_init(struct bch_fs *c) -{ - init_waitqueue_head(&c->copygc_running_wq); - c->copygc_running = false; -} |