// SPDX-License-Identifier: GPL-2.0 #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 "compress.h" #include "disk_groups.h" #include "errcode.h" #include "error.h" #include "inode.h" #include "move.h" #include "rebalance.h" #include "subvolume.h" #include "super-io.h" #include "trace.h" #include #include #include #define REBALANCE_WORK_SCAN_OFFSET (U64_MAX - 1) static const char * const bch2_rebalance_state_strs[] = { #define x(t) #t, BCH_REBALANCE_STATES() NULL #undef x }; static int __bch2_set_rebalance_needs_scan(struct btree_trans *trans, u64 inum) { struct btree_iter iter; struct bkey_s_c k; struct bkey_i_cookie *cookie; u64 v; int ret; bch2_trans_iter_init(trans, &iter, BTREE_ID_rebalance_work, SPOS(inum, REBALANCE_WORK_SCAN_OFFSET, U32_MAX), BTREE_ITER_intent); k = bch2_btree_iter_peek_slot(&iter); ret = bkey_err(k); if (ret) goto err; v = k.k->type == KEY_TYPE_cookie ? le64_to_cpu(bkey_s_c_to_cookie(k).v->cookie) : 0; cookie = bch2_trans_kmalloc(trans, sizeof(*cookie)); ret = PTR_ERR_OR_ZERO(cookie); if (ret) goto err; bkey_cookie_init(&cookie->k_i); cookie->k.p = iter.pos; cookie->v.cookie = cpu_to_le64(v + 1); ret = bch2_trans_update(trans, &iter, &cookie->k_i, 0); err: bch2_trans_iter_exit(trans, &iter); return ret; } int bch2_set_rebalance_needs_scan(struct bch_fs *c, u64 inum) { int ret = bch2_trans_do(c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc|BCH_TRANS_COMMIT_lazy_rw, __bch2_set_rebalance_needs_scan(trans, inum)); rebalance_wakeup(c); return ret; } int bch2_set_fs_needs_rebalance(struct bch_fs *c) { return bch2_set_rebalance_needs_scan(c, 0); } static int bch2_clear_rebalance_needs_scan(struct btree_trans *trans, u64 inum, u64 cookie) { struct btree_iter iter; struct bkey_s_c k; u64 v; int ret; bch2_trans_iter_init(trans, &iter, BTREE_ID_rebalance_work, SPOS(inum, REBALANCE_WORK_SCAN_OFFSET, U32_MAX), BTREE_ITER_intent); k = bch2_btree_iter_peek_slot(&iter); ret = bkey_err(k); if (ret) goto err; v = k.k->type == KEY_TYPE_cookie ? le64_to_cpu(bkey_s_c_to_cookie(k).v->cookie) : 0; if (v == cookie) ret = bch2_btree_delete_at(trans, &iter, 0); err: bch2_trans_iter_exit(trans, &iter); return ret; } static struct bkey_s_c next_rebalance_entry(struct btree_trans *trans, struct btree_iter *work_iter) { return !kthread_should_stop() ? bch2_btree_iter_peek(work_iter) : bkey_s_c_null; } static int bch2_bkey_clear_needs_rebalance(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c k) { struct bkey_i *n = bch2_bkey_make_mut(trans, iter, &k, 0); int ret = PTR_ERR_OR_ZERO(n); if (ret) return ret; extent_entry_drop(bkey_i_to_s(n), (void *) bch2_bkey_rebalance_opts(bkey_i_to_s_c(n))); return bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc); } static struct bkey_s_c next_rebalance_extent(struct btree_trans *trans, struct bpos work_pos, struct btree_iter *extent_iter, struct data_update_opts *data_opts) { struct bch_fs *c = trans->c; struct bkey_s_c k; bch2_trans_iter_exit(trans, extent_iter); bch2_trans_iter_init(trans, extent_iter, work_pos.inode ? BTREE_ID_extents : BTREE_ID_reflink, work_pos, BTREE_ITER_all_snapshots); k = bch2_btree_iter_peek_slot(extent_iter); if (bkey_err(k)) return k; const struct bch_extent_rebalance *r = k.k ? bch2_bkey_rebalance_opts(k) : NULL; if (!r) { /* raced due to btree write buffer, nothing to do */ return bkey_s_c_null; } memset(data_opts, 0, sizeof(*data_opts)); data_opts->rewrite_ptrs = bch2_bkey_ptrs_need_rebalance(c, k, r->target, r->compression); data_opts->target = r->target; if (!data_opts->rewrite_ptrs) { /* * device we would want to write to offline? devices in target * changed? * * We'll now need a full scan before this extent is picked up * again: */ int ret = bch2_bkey_clear_needs_rebalance(trans, extent_iter, k); if (ret) return bkey_s_c_err(ret); return bkey_s_c_null; } if (trace_rebalance_extent_enabled()) { struct printbuf buf = PRINTBUF; prt_str(&buf, "target="); bch2_target_to_text(&buf, c, r->target); prt_str(&buf, " compression="); bch2_compression_opt_to_text(&buf, r->compression); prt_str(&buf, " "); bch2_bkey_val_to_text(&buf, c, k); trace_rebalance_extent(c, buf.buf); printbuf_exit(&buf); } return k; } noinline_for_stack static int do_rebalance_extent(struct moving_context *ctxt, struct bpos work_pos, struct btree_iter *extent_iter) { struct btree_trans *trans = ctxt->trans; struct bch_fs *c = trans->c; struct bch_fs_rebalance *r = &trans->c->rebalance; struct data_update_opts data_opts; struct bch_io_opts io_opts; struct bkey_s_c k; struct bkey_buf sk; int ret; ctxt->stats = &r->work_stats; r->state = BCH_REBALANCE_working; bch2_bkey_buf_init(&sk); ret = bkey_err(k = next_rebalance_extent(trans, work_pos, extent_iter, &data_opts)); if (ret || !k.k) goto out; ret = bch2_move_get_io_opts_one(trans, &io_opts, k); if (ret) goto out; atomic64_add(k.k->size, &ctxt->stats->sectors_seen); /* * The iterator gets unlocked by __bch2_read_extent - need to * save a copy of @k elsewhere: */ bch2_bkey_buf_reassemble(&sk, c, k); k = bkey_i_to_s_c(sk.k); ret = bch2_move_extent(ctxt, NULL, extent_iter, k, io_opts, data_opts); if (ret) { if (bch2_err_matches(ret, ENOMEM)) { /* memory allocation failure, wait for some IO to finish */ bch2_move_ctxt_wait_for_io(ctxt); ret = -BCH_ERR_transaction_restart_nested; } if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) goto out; /* skip it and continue, XXX signal failure */ ret = 0; } out: bch2_bkey_buf_exit(&sk, c); return ret; } static bool rebalance_pred(struct bch_fs *c, void *arg, struct bkey_s_c k, struct bch_io_opts *io_opts, struct data_update_opts *data_opts) { unsigned target, compression; if (k.k->p.inode) { target = io_opts->background_target; compression = background_compression(*io_opts); } else { const struct bch_extent_rebalance *r = bch2_bkey_rebalance_opts(k); target = r ? r->target : io_opts->background_target; compression = r ? r->compression : background_compression(*io_opts); } data_opts->rewrite_ptrs = bch2_bkey_ptrs_need_rebalance(c, k, target, compression); data_opts->target = target; return data_opts->rewrite_ptrs != 0; } static int do_rebalance_scan(struct moving_context *ctxt, u64 inum, u64 cookie) { struct btree_trans *trans = ctxt->trans; struct bch_fs_rebalance *r = &trans->c->rebalance; int ret; bch2_move_stats_init(&r->scan_stats, "rebalance_scan"); ctxt->stats = &r->scan_stats; if (!inum) { r->scan_start = BBPOS_MIN; r->scan_end = BBPOS_MAX; } else { r->scan_start = BBPOS(BTREE_ID_extents, POS(inum, 0)); r->scan_end = BBPOS(BTREE_ID_extents, POS(inum, U64_MAX)); } r->state = BCH_REBALANCE_scanning; ret = __bch2_move_data(ctxt, r->scan_start, r->scan_end, rebalance_pred, NULL) ?: commit_do(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc, bch2_clear_rebalance_needs_scan(trans, inum, cookie)); bch2_move_stats_exit(&r->scan_stats, trans->c); return ret; } static void rebalance_wait(struct bch_fs *c) { struct bch_fs_rebalance *r = &c->rebalance; struct io_clock *clock = &c->io_clock[WRITE]; u64 now = atomic64_read(&clock->now); u64 min_member_capacity = bch2_min_rw_member_capacity(c); if (min_member_capacity == U64_MAX) min_member_capacity = 128 * 2048; r->wait_iotime_end = now + (min_member_capacity >> 6); if (r->state != BCH_REBALANCE_waiting) { r->wait_iotime_start = now; r->wait_wallclock_start = ktime_get_real_ns(); r->state = BCH_REBALANCE_waiting; } bch2_kthread_io_clock_wait(clock, r->wait_iotime_end, MAX_SCHEDULE_TIMEOUT); } static int do_rebalance(struct moving_context *ctxt) { struct btree_trans *trans = ctxt->trans; struct bch_fs *c = trans->c; struct bch_fs_rebalance *r = &c->rebalance; struct btree_iter rebalance_work_iter, extent_iter = { NULL }; struct bkey_s_c k; int ret = 0; bch2_move_stats_init(&r->work_stats, "rebalance_work"); bch2_move_stats_init(&r->scan_stats, "rebalance_scan"); bch2_trans_iter_init(trans, &rebalance_work_iter, BTREE_ID_rebalance_work, POS_MIN, BTREE_ITER_all_snapshots); while (!bch2_move_ratelimit(ctxt)) { if (!r->enabled) { bch2_moving_ctxt_flush_all(ctxt); kthread_wait_freezable(r->enabled || kthread_should_stop()); } if (kthread_should_stop()) break; bch2_trans_begin(trans); ret = bkey_err(k = next_rebalance_entry(trans, &rebalance_work_iter)); if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) continue; if (ret || !k.k) break; ret = k.k->type == KEY_TYPE_cookie ? do_rebalance_scan(ctxt, k.k->p.inode, le64_to_cpu(bkey_s_c_to_cookie(k).v->cookie)) : do_rebalance_extent(ctxt, k.k->p, &extent_iter); if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) continue; if (ret) break; bch2_btree_iter_advance(&rebalance_work_iter); } bch2_trans_iter_exit(trans, &extent_iter); bch2_trans_iter_exit(trans, &rebalance_work_iter); bch2_move_stats_exit(&r->scan_stats, c); if (!ret && !kthread_should_stop() && !atomic64_read(&r->work_stats.sectors_seen) && !atomic64_read(&r->scan_stats.sectors_seen)) { bch2_moving_ctxt_flush_all(ctxt); bch2_trans_unlock_long(trans); rebalance_wait(c); } if (!bch2_err_matches(ret, EROFS)) bch_err_fn(c, ret); return ret; } static int bch2_rebalance_thread(void *arg) { struct bch_fs *c = arg; struct bch_fs_rebalance *r = &c->rebalance; struct moving_context ctxt; set_freezable(); bch2_moving_ctxt_init(&ctxt, c, NULL, &r->work_stats, writepoint_ptr(&c->rebalance_write_point), true); while (!kthread_should_stop() && !do_rebalance(&ctxt)) ; bch2_moving_ctxt_exit(&ctxt); return 0; } void bch2_rebalance_status_to_text(struct printbuf *out, struct bch_fs *c) { struct bch_fs_rebalance *r = &c->rebalance; prt_str(out, bch2_rebalance_state_strs[r->state]); prt_newline(out); printbuf_indent_add(out, 2); switch (r->state) { case BCH_REBALANCE_waiting: { u64 now = atomic64_read(&c->io_clock[WRITE].now); prt_str(out, "io wait duration: "); bch2_prt_human_readable_s64(out, (r->wait_iotime_end - r->wait_iotime_start) << 9); prt_newline(out); prt_str(out, "io wait remaining: "); bch2_prt_human_readable_s64(out, (r->wait_iotime_end - now) << 9); prt_newline(out); prt_str(out, "duration waited: "); bch2_pr_time_units(out, ktime_get_real_ns() - r->wait_wallclock_start); prt_newline(out); break; } case BCH_REBALANCE_working: bch2_move_stats_to_text(out, &r->work_stats); break; case BCH_REBALANCE_scanning: bch2_move_stats_to_text(out, &r->scan_stats); break; } prt_newline(out); printbuf_indent_sub(out, 2); } void bch2_rebalance_stop(struct bch_fs *c) { struct task_struct *p; c->rebalance.pd.rate.rate = UINT_MAX; bch2_ratelimit_reset(&c->rebalance.pd.rate); p = rcu_dereference_protected(c->rebalance.thread, 1); c->rebalance.thread = NULL; if (p) { /* for sychronizing with rebalance_wakeup() */ synchronize_rcu(); kthread_stop(p); put_task_struct(p); } } int bch2_rebalance_start(struct bch_fs *c) { struct task_struct *p; int ret; if (c->rebalance.thread) return 0; if (c->opts.nochanges) return 0; p = kthread_create(bch2_rebalance_thread, c, "bch-rebalance/%s", c->name); ret = PTR_ERR_OR_ZERO(p); bch_err_msg(c, ret, "creating rebalance thread"); if (ret) return ret; get_task_struct(p); rcu_assign_pointer(c->rebalance.thread, p); wake_up_process(p); return 0; } void bch2_fs_rebalance_init(struct bch_fs *c) { bch2_pd_controller_init(&c->rebalance.pd); }