diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/fld/fld_cache.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/fld/fld_cache.c | 517 |
1 files changed, 0 insertions, 517 deletions
diff --git a/drivers/staging/lustre/lustre/fld/fld_cache.c b/drivers/staging/lustre/lustre/fld/fld_cache.c deleted file mode 100644 index 2d61ca4e51cf..000000000000 --- a/drivers/staging/lustre/lustre/fld/fld_cache.c +++ /dev/null @@ -1,517 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * GPL HEADER START - * - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 only, - * 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 version 2 for more details (a copy is included - * in the LICENSE file that accompanied this code). - * - * You should have received a copy of the GNU General Public License - * version 2 along with this program; If not, see - * http://www.gnu.org/licenses/gpl-2.0.html - * - * GPL HEADER END - */ -/* - * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. - * Use is subject to license terms. - * - * Copyright (c) 2012, 2013, Intel Corporation. - */ -/* - * This file is part of Lustre, http://www.lustre.org/ - * Lustre is a trademark of Sun Microsystems, Inc. - * - * lustre/fld/fld_cache.c - * - * FLD (Fids Location Database) - * - * Author: Pravin Shelar <pravin.shelar@sun.com> - * Author: Yury Umanets <umka@clusterfs.com> - */ - -#define DEBUG_SUBSYSTEM S_FLD - -#include <linux/libcfs/libcfs.h> -#include <linux/module.h> -#include <asm/div64.h> - -#include <obd.h> -#include <obd_class.h> -#include <uapi/linux/lustre/lustre_ver.h> -#include <obd_support.h> -#include <lprocfs_status.h> - -#include <lustre_req_layout.h> -#include <lustre_fld.h> -#include "fld_internal.h" - -/** - * create fld cache. - */ -struct fld_cache *fld_cache_init(const char *name, - int cache_size, int cache_threshold) -{ - struct fld_cache *cache; - - LASSERT(name); - LASSERT(cache_threshold < cache_size); - - cache = kzalloc(sizeof(*cache), GFP_NOFS); - if (!cache) - return ERR_PTR(-ENOMEM); - - INIT_LIST_HEAD(&cache->fci_entries_head); - INIT_LIST_HEAD(&cache->fci_lru); - - cache->fci_cache_count = 0; - rwlock_init(&cache->fci_lock); - - strlcpy(cache->fci_name, name, - sizeof(cache->fci_name)); - - cache->fci_cache_size = cache_size; - cache->fci_threshold = cache_threshold; - - /* Init fld cache info. */ - memset(&cache->fci_stat, 0, sizeof(cache->fci_stat)); - - CDEBUG(D_INFO, "%s: FLD cache - Size: %d, Threshold: %d\n", - cache->fci_name, cache_size, cache_threshold); - - return cache; -} - -/** - * destroy fld cache. - */ -void fld_cache_fini(struct fld_cache *cache) -{ - __u64 pct; - - LASSERT(cache); - fld_cache_flush(cache); - - if (cache->fci_stat.fst_count > 0) { - pct = cache->fci_stat.fst_cache * 100; - do_div(pct, cache->fci_stat.fst_count); - } else { - pct = 0; - } - - CDEBUG(D_INFO, "FLD cache statistics (%s):\n", cache->fci_name); - CDEBUG(D_INFO, " Total reqs: %llu\n", cache->fci_stat.fst_count); - CDEBUG(D_INFO, " Cache reqs: %llu\n", cache->fci_stat.fst_cache); - CDEBUG(D_INFO, " Cache hits: %llu%%\n", pct); - - kfree(cache); -} - -/** - * delete given node from list. - */ -static void fld_cache_entry_delete(struct fld_cache *cache, - struct fld_cache_entry *node) -{ - list_del(&node->fce_list); - list_del(&node->fce_lru); - cache->fci_cache_count--; - kfree(node); -} - -/** - * fix list by checking new entry with NEXT entry in order. - */ -static void fld_fix_new_list(struct fld_cache *cache) -{ - struct fld_cache_entry *f_curr; - struct fld_cache_entry *f_next; - struct lu_seq_range *c_range; - struct lu_seq_range *n_range; - struct list_head *head = &cache->fci_entries_head; - -restart_fixup: - - list_for_each_entry_safe(f_curr, f_next, head, fce_list) { - c_range = &f_curr->fce_range; - n_range = &f_next->fce_range; - - LASSERT(lu_seq_range_is_sane(c_range)); - if (&f_next->fce_list == head) - break; - - if (c_range->lsr_flags != n_range->lsr_flags) - continue; - - LASSERTF(c_range->lsr_start <= n_range->lsr_start, - "cur lsr_start " DRANGE " next lsr_start " DRANGE "\n", - PRANGE(c_range), PRANGE(n_range)); - - /* check merge possibility with next range */ - if (c_range->lsr_end == n_range->lsr_start) { - if (c_range->lsr_index != n_range->lsr_index) - continue; - n_range->lsr_start = c_range->lsr_start; - fld_cache_entry_delete(cache, f_curr); - continue; - } - - /* check if current range overlaps with next range. */ - if (n_range->lsr_start < c_range->lsr_end) { - if (c_range->lsr_index == n_range->lsr_index) { - n_range->lsr_start = c_range->lsr_start; - n_range->lsr_end = max(c_range->lsr_end, - n_range->lsr_end); - fld_cache_entry_delete(cache, f_curr); - } else { - if (n_range->lsr_end <= c_range->lsr_end) { - *n_range = *c_range; - fld_cache_entry_delete(cache, f_curr); - } else { - n_range->lsr_start = c_range->lsr_end; - } - } - - /* we could have overlap over next - * range too. better restart. - */ - goto restart_fixup; - } - - /* kill duplicates */ - if (c_range->lsr_start == n_range->lsr_start && - c_range->lsr_end == n_range->lsr_end) - fld_cache_entry_delete(cache, f_curr); - } -} - -/** - * add node to fld cache - */ -static inline void fld_cache_entry_add(struct fld_cache *cache, - struct fld_cache_entry *f_new, - struct list_head *pos) -{ - list_add(&f_new->fce_list, pos); - list_add(&f_new->fce_lru, &cache->fci_lru); - - cache->fci_cache_count++; - fld_fix_new_list(cache); -} - -/** - * Check if cache needs to be shrunk. If so - do it. - * Remove one entry in list and so on until cache is shrunk enough. - */ -static int fld_cache_shrink(struct fld_cache *cache) -{ - int num = 0; - - if (cache->fci_cache_count < cache->fci_cache_size) - return 0; - - while (cache->fci_cache_count + cache->fci_threshold > - cache->fci_cache_size && - !list_empty(&cache->fci_lru)) { - struct fld_cache_entry *flde = - list_last_entry(&cache->fci_lru, - struct fld_cache_entry, fce_lru); - - fld_cache_entry_delete(cache, flde); - num++; - } - - CDEBUG(D_INFO, "%s: FLD cache - Shrunk by %d entries\n", - cache->fci_name, num); - - return 0; -} - -/** - * kill all fld cache entries. - */ -void fld_cache_flush(struct fld_cache *cache) -{ - write_lock(&cache->fci_lock); - cache->fci_cache_size = 0; - fld_cache_shrink(cache); - write_unlock(&cache->fci_lock); -} - -/** - * punch hole in existing range. divide this range and add new - * entry accordingly. - */ - -static void fld_cache_punch_hole(struct fld_cache *cache, - struct fld_cache_entry *f_curr, - struct fld_cache_entry *f_new) -{ - const struct lu_seq_range *range = &f_new->fce_range; - const u64 new_start = range->lsr_start; - const u64 new_end = range->lsr_end; - struct fld_cache_entry *fldt; - - fldt = kzalloc(sizeof(*fldt), GFP_ATOMIC); - if (!fldt) { - kfree(f_new); - /* overlap is not allowed, so don't mess up list. */ - return; - } - /* break f_curr RANGE into three RANGES: - * f_curr, f_new , fldt - */ - - /* f_new = *range */ - - /* fldt */ - fldt->fce_range.lsr_start = new_end; - fldt->fce_range.lsr_end = f_curr->fce_range.lsr_end; - fldt->fce_range.lsr_index = f_curr->fce_range.lsr_index; - - /* f_curr */ - f_curr->fce_range.lsr_end = new_start; - - /* add these two entries to list */ - fld_cache_entry_add(cache, f_new, &f_curr->fce_list); - fld_cache_entry_add(cache, fldt, &f_new->fce_list); - - /* no need to fixup */ -} - -/** - * handle range overlap in fld cache. - */ -static void fld_cache_overlap_handle(struct fld_cache *cache, - struct fld_cache_entry *f_curr, - struct fld_cache_entry *f_new) -{ - const struct lu_seq_range *range = &f_new->fce_range; - const u64 new_start = range->lsr_start; - const u64 new_end = range->lsr_end; - const u32 mdt = range->lsr_index; - - /* this is overlap case, these case are checking overlapping with - * prev range only. fixup will handle overlapping with next range. - */ - - if (f_curr->fce_range.lsr_index == mdt) { - f_curr->fce_range.lsr_start = min(f_curr->fce_range.lsr_start, - new_start); - - f_curr->fce_range.lsr_end = max(f_curr->fce_range.lsr_end, - new_end); - - kfree(f_new); - fld_fix_new_list(cache); - - } else if (new_start <= f_curr->fce_range.lsr_start && - f_curr->fce_range.lsr_end <= new_end) { - /* case 1: new range completely overshadowed existing range. - * e.g. whole range migrated. update fld cache entry - */ - - f_curr->fce_range = *range; - kfree(f_new); - fld_fix_new_list(cache); - - } else if (f_curr->fce_range.lsr_start < new_start && - new_end < f_curr->fce_range.lsr_end) { - /* case 2: new range fit within existing range. */ - - fld_cache_punch_hole(cache, f_curr, f_new); - - } else if (new_end <= f_curr->fce_range.lsr_end) { - /* case 3: overlap: - * [new_start [c_start new_end) c_end) - */ - - LASSERT(new_start <= f_curr->fce_range.lsr_start); - - f_curr->fce_range.lsr_start = new_end; - fld_cache_entry_add(cache, f_new, f_curr->fce_list.prev); - - } else if (f_curr->fce_range.lsr_start <= new_start) { - /* case 4: overlap: - * [c_start [new_start c_end) new_end) - */ - - LASSERT(f_curr->fce_range.lsr_end <= new_end); - - f_curr->fce_range.lsr_end = new_start; - fld_cache_entry_add(cache, f_new, &f_curr->fce_list); - } else { - CERROR("NEW range =" DRANGE " curr = " DRANGE "\n", - PRANGE(range), PRANGE(&f_curr->fce_range)); - } -} - -struct fld_cache_entry -*fld_cache_entry_create(const struct lu_seq_range *range) -{ - struct fld_cache_entry *f_new; - - LASSERT(lu_seq_range_is_sane(range)); - - f_new = kzalloc(sizeof(*f_new), GFP_NOFS); - if (!f_new) - return ERR_PTR(-ENOMEM); - - f_new->fce_range = *range; - return f_new; -} - -/** - * Insert FLD entry in FLD cache. - * - * This function handles all cases of merging and breaking up of - * ranges. - */ -static int fld_cache_insert_nolock(struct fld_cache *cache, - struct fld_cache_entry *f_new) -{ - struct fld_cache_entry *f_curr; - struct fld_cache_entry *n; - struct list_head *head; - struct list_head *prev = NULL; - const u64 new_start = f_new->fce_range.lsr_start; - const u64 new_end = f_new->fce_range.lsr_end; - __u32 new_flags = f_new->fce_range.lsr_flags; - - /* - * Duplicate entries are eliminated in insert op. - * So we don't need to search new entry before starting - * insertion loop. - */ - - if (!cache->fci_no_shrink) - fld_cache_shrink(cache); - - head = &cache->fci_entries_head; - - list_for_each_entry_safe(f_curr, n, head, fce_list) { - /* add list if next is end of list */ - if (new_end < f_curr->fce_range.lsr_start || - (new_end == f_curr->fce_range.lsr_start && - new_flags != f_curr->fce_range.lsr_flags)) - break; - - prev = &f_curr->fce_list; - /* check if this range is to left of new range. */ - if (new_start < f_curr->fce_range.lsr_end && - new_flags == f_curr->fce_range.lsr_flags) { - fld_cache_overlap_handle(cache, f_curr, f_new); - goto out; - } - } - - if (!prev) - prev = head; - - CDEBUG(D_INFO, "insert range " DRANGE "\n", PRANGE(&f_new->fce_range)); - /* Add new entry to cache and lru list. */ - fld_cache_entry_add(cache, f_new, prev); -out: - return 0; -} - -int fld_cache_insert(struct fld_cache *cache, - const struct lu_seq_range *range) -{ - struct fld_cache_entry *flde; - int rc; - - flde = fld_cache_entry_create(range); - if (IS_ERR(flde)) - return PTR_ERR(flde); - - write_lock(&cache->fci_lock); - rc = fld_cache_insert_nolock(cache, flde); - write_unlock(&cache->fci_lock); - if (rc) - kfree(flde); - - return rc; -} - -/** - * Delete FLD entry in FLD cache. - * - */ - -struct fld_cache_entry -*fld_cache_entry_lookup_nolock(struct fld_cache *cache, - struct lu_seq_range *range) -{ - struct fld_cache_entry *flde; - struct fld_cache_entry *got = NULL; - struct list_head *head; - - head = &cache->fci_entries_head; - list_for_each_entry(flde, head, fce_list) { - if (range->lsr_start == flde->fce_range.lsr_start || - (range->lsr_end == flde->fce_range.lsr_end && - range->lsr_flags == flde->fce_range.lsr_flags)) { - got = flde; - break; - } - } - - return got; -} - -/** - * lookup \a seq sequence for range in fld cache. - */ -struct fld_cache_entry -*fld_cache_entry_lookup(struct fld_cache *cache, struct lu_seq_range *range) -{ - struct fld_cache_entry *got = NULL; - - read_lock(&cache->fci_lock); - got = fld_cache_entry_lookup_nolock(cache, range); - read_unlock(&cache->fci_lock); - return got; -} - -/** - * lookup \a seq sequence for range in fld cache. - */ -int fld_cache_lookup(struct fld_cache *cache, - const u64 seq, struct lu_seq_range *range) -{ - struct fld_cache_entry *flde; - struct fld_cache_entry *prev = NULL; - struct list_head *head; - - read_lock(&cache->fci_lock); - head = &cache->fci_entries_head; - - cache->fci_stat.fst_count++; - list_for_each_entry(flde, head, fce_list) { - if (flde->fce_range.lsr_start > seq) { - if (prev) - *range = prev->fce_range; - break; - } - - prev = flde; - if (lu_seq_range_within(&flde->fce_range, seq)) { - *range = flde->fce_range; - - cache->fci_stat.fst_cache++; - read_unlock(&cache->fci_lock); - return 0; - } - } - read_unlock(&cache->fci_lock); - return -ENOENT; -} |