From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- drivers/lightnvm/pblk-rl.c | 254 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 254 insertions(+) create mode 100644 drivers/lightnvm/pblk-rl.c (limited to 'drivers/lightnvm/pblk-rl.c') diff --git a/drivers/lightnvm/pblk-rl.c b/drivers/lightnvm/pblk-rl.c new file mode 100644 index 000000000..a5f8bc2de --- /dev/null +++ b/drivers/lightnvm/pblk-rl.c @@ -0,0 +1,254 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2016 CNEX Labs + * Initial release: Javier Gonzalez + * Matias Bjorling + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * pblk-rl.c - pblk's rate limiter for user I/O + * + */ + +#include "pblk.h" + +static void pblk_rl_kick_u_timer(struct pblk_rl *rl) +{ + mod_timer(&rl->u_timer, jiffies + msecs_to_jiffies(5000)); +} + +int pblk_rl_is_limit(struct pblk_rl *rl) +{ + int rb_space; + + rb_space = atomic_read(&rl->rb_space); + + return (rb_space == 0); +} + +int pblk_rl_user_may_insert(struct pblk_rl *rl, int nr_entries) +{ + int rb_user_cnt = atomic_read(&rl->rb_user_cnt); + int rb_space = atomic_read(&rl->rb_space); + + if (unlikely(rb_space >= 0) && (rb_space - nr_entries < 0)) + return NVM_IO_ERR; + + if (rb_user_cnt >= rl->rb_user_max) + return NVM_IO_REQUEUE; + + return NVM_IO_OK; +} + +void pblk_rl_inserted(struct pblk_rl *rl, int nr_entries) +{ + int rb_space = atomic_read(&rl->rb_space); + + if (unlikely(rb_space >= 0)) + atomic_sub(nr_entries, &rl->rb_space); +} + +int pblk_rl_gc_may_insert(struct pblk_rl *rl, int nr_entries) +{ + int rb_gc_cnt = atomic_read(&rl->rb_gc_cnt); + int rb_user_active; + + /* If there is no user I/O let GC take over space on the write buffer */ + rb_user_active = READ_ONCE(rl->rb_user_active); + return (!(rb_gc_cnt >= rl->rb_gc_max && rb_user_active)); +} + +void pblk_rl_user_in(struct pblk_rl *rl, int nr_entries) +{ + atomic_add(nr_entries, &rl->rb_user_cnt); + + /* Release user I/O state. Protect from GC */ + smp_store_release(&rl->rb_user_active, 1); + pblk_rl_kick_u_timer(rl); +} + +void pblk_rl_werr_line_in(struct pblk_rl *rl) +{ + atomic_inc(&rl->werr_lines); +} + +void pblk_rl_werr_line_out(struct pblk_rl *rl) +{ + atomic_dec(&rl->werr_lines); +} + +void pblk_rl_gc_in(struct pblk_rl *rl, int nr_entries) +{ + atomic_add(nr_entries, &rl->rb_gc_cnt); +} + +void pblk_rl_out(struct pblk_rl *rl, int nr_user, int nr_gc) +{ + atomic_sub(nr_user, &rl->rb_user_cnt); + atomic_sub(nr_gc, &rl->rb_gc_cnt); +} + +unsigned long pblk_rl_nr_free_blks(struct pblk_rl *rl) +{ + return atomic_read(&rl->free_blocks); +} + +unsigned long pblk_rl_nr_user_free_blks(struct pblk_rl *rl) +{ + return atomic_read(&rl->free_user_blocks); +} + +static void __pblk_rl_update_rates(struct pblk_rl *rl, + unsigned long free_blocks) +{ + struct pblk *pblk = container_of(rl, struct pblk, rl); + int max = rl->rb_budget; + int werr_gc_needed = atomic_read(&rl->werr_lines); + + if (free_blocks >= rl->high) { + if (werr_gc_needed) { + /* Allocate a small budget for recovering + * lines with write errors + */ + rl->rb_gc_max = 1 << rl->rb_windows_pw; + rl->rb_user_max = max - rl->rb_gc_max; + rl->rb_state = PBLK_RL_WERR; + } else { + rl->rb_user_max = max; + rl->rb_gc_max = 0; + rl->rb_state = PBLK_RL_OFF; + } + } else if (free_blocks < rl->high) { + int shift = rl->high_pw - rl->rb_windows_pw; + int user_windows = free_blocks >> shift; + int user_max = user_windows << ilog2(NVM_MAX_VLBA); + + rl->rb_user_max = user_max; + rl->rb_gc_max = max - user_max; + + if (free_blocks <= rl->rsv_blocks) { + rl->rb_user_max = 0; + rl->rb_gc_max = max; + } + + /* In the worst case, we will need to GC lines in the low list + * (high valid sector count). If there are lines to GC on high + * or mid lists, these will be prioritized + */ + rl->rb_state = PBLK_RL_LOW; + } + + if (rl->rb_state != PBLK_RL_OFF) + pblk_gc_should_start(pblk); + else + pblk_gc_should_stop(pblk); +} + +void pblk_rl_update_rates(struct pblk_rl *rl) +{ + __pblk_rl_update_rates(rl, pblk_rl_nr_user_free_blks(rl)); +} + +void pblk_rl_free_lines_inc(struct pblk_rl *rl, struct pblk_line *line) +{ + int blk_in_line = atomic_read(&line->blk_in_line); + int free_blocks; + + atomic_add(blk_in_line, &rl->free_blocks); + free_blocks = atomic_add_return(blk_in_line, &rl->free_user_blocks); + + __pblk_rl_update_rates(rl, free_blocks); +} + +void pblk_rl_free_lines_dec(struct pblk_rl *rl, struct pblk_line *line, + bool used) +{ + int blk_in_line = atomic_read(&line->blk_in_line); + int free_blocks; + + atomic_sub(blk_in_line, &rl->free_blocks); + + if (used) + free_blocks = atomic_sub_return(blk_in_line, + &rl->free_user_blocks); + else + free_blocks = atomic_read(&rl->free_user_blocks); + + __pblk_rl_update_rates(rl, free_blocks); +} + +int pblk_rl_high_thrs(struct pblk_rl *rl) +{ + return rl->high; +} + +int pblk_rl_max_io(struct pblk_rl *rl) +{ + return rl->rb_max_io; +} + +static void pblk_rl_u_timer(struct timer_list *t) +{ + struct pblk_rl *rl = from_timer(rl, t, u_timer); + + /* Release user I/O state. Protect from GC */ + smp_store_release(&rl->rb_user_active, 0); +} + +void pblk_rl_free(struct pblk_rl *rl) +{ + del_timer(&rl->u_timer); +} + +void pblk_rl_init(struct pblk_rl *rl, int budget, int threshold) +{ + struct pblk *pblk = container_of(rl, struct pblk, rl); + struct nvm_tgt_dev *dev = pblk->dev; + struct nvm_geo *geo = &dev->geo; + struct pblk_line_mgmt *l_mg = &pblk->l_mg; + struct pblk_line_meta *lm = &pblk->lm; + int sec_meta, blk_meta; + unsigned int rb_windows; + + /* Consider sectors used for metadata */ + sec_meta = (lm->smeta_sec + lm->emeta_sec[0]) * l_mg->nr_free_lines; + blk_meta = DIV_ROUND_UP(sec_meta, geo->clba); + + rl->high = pblk->op_blks - blk_meta - lm->blk_per_line; + rl->high_pw = get_count_order(rl->high); + + rl->rsv_blocks = pblk_get_min_chks(pblk); + + /* This will always be a power-of-2 */ + rb_windows = budget / NVM_MAX_VLBA; + rl->rb_windows_pw = get_count_order(rb_windows); + + /* To start with, all buffer is available to user I/O writers */ + rl->rb_budget = budget; + rl->rb_user_max = budget; + rl->rb_gc_max = 0; + rl->rb_state = PBLK_RL_HIGH; + + /* Maximize I/O size and ansure that back threshold is respected */ + if (threshold) + rl->rb_max_io = budget - pblk->min_write_pgs_data - threshold; + else + rl->rb_max_io = budget - pblk->min_write_pgs_data - 1; + + atomic_set(&rl->rb_user_cnt, 0); + atomic_set(&rl->rb_gc_cnt, 0); + atomic_set(&rl->rb_space, -1); + atomic_set(&rl->werr_lines, 0); + + timer_setup(&rl->u_timer, pblk_rl_u_timer, 0); + + rl->rb_user_active = 0; + rl->rb_gc_active = 0; +} -- cgit v1.2.3