diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt index 44317f7bf837..dce85efb177e 100644 --- a/Documentation/blockdev/zram.txt +++ b/Documentation/blockdev/zram.txt @@ -221,8 +221,6 @@ line of text and contains the following stats separated by whitespace: same_pages the number of same element filled pages written to this disk. No memory is allocated for such pages. pages_compacted the number of pages freed during compaction - dup_data_size deduplicated data size - meta_data_size the amount of metadata allocated for deduplication feature huge_pages the number of incompressible pages File /sys/block/zram/bd_stat diff --git a/drivers/block/zram/Makefile b/drivers/block/zram/Makefile index 29cb0082bb0c..9e2b79e9a990 100644 --- a/drivers/block/zram/Makefile +++ b/drivers/block/zram/Makefile @@ -1,3 +1,3 @@ -zram-y := zcomp.o zram_drv.o zram_dedup.o +zram-y := zcomp.o zram_drv.o obj-$(CONFIG_ZRAM) += zram.o diff --git a/drivers/block/zram/zram_dedup.c b/drivers/block/zram/zram_dedup.c deleted file mode 100644 index a8427f75b6ea..000000000000 --- a/drivers/block/zram/zram_dedup.c +++ /dev/null @@ -1,204 +0,0 @@ -/* - * Copyright (C) 2017 Joonsoo Kim. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#include -#include -#include - -#include "zram_drv.h" - -/* One slot will contain 128 pages theoretically */ -#define ZRAM_HASH_SHIFT 7 -#define ZRAM_HASH_SIZE_MIN (1 << 10) -#define ZRAM_HASH_SIZE_MAX (1 << 31) - -u64 zram_dedup_dup_size(struct zram *zram) -{ - return (u64)atomic64_read(&zram->stats.dup_data_size); -} - -u64 zram_dedup_meta_size(struct zram *zram) -{ - return (u64)atomic64_read(&zram->stats.meta_data_size); -} - -static u32 zram_dedup_checksum(unsigned char *mem) -{ - return jhash(mem, PAGE_SIZE, 0); -} - -void zram_dedup_insert(struct zram *zram, struct zram_entry *new, - u32 checksum) -{ - struct zram_hash *hash; - struct rb_root *rb_root; - struct rb_node **rb_node, *parent = NULL; - struct zram_entry *entry; - - new->checksum = checksum; - hash = &zram->hash[checksum % zram->hash_size]; - rb_root = &hash->rb_root; - - spin_lock(&hash->lock); - rb_node = &rb_root->rb_node; - while (*rb_node) { - parent = *rb_node; - entry = rb_entry(parent, struct zram_entry, rb_node); - if (checksum < entry->checksum) - rb_node = &parent->rb_left; - else if (checksum > entry->checksum) - rb_node = &parent->rb_right; - else - rb_node = &parent->rb_left; - } - - rb_link_node(&new->rb_node, parent, rb_node); - rb_insert_color(&new->rb_node, rb_root); - spin_unlock(&hash->lock); -} - -static bool zram_dedup_match(struct zram *zram, struct zram_entry *entry, - unsigned char *mem) -{ - bool match = false; - unsigned char *cmem; - struct zcomp_strm *zstrm; - - cmem = zs_map_object(zram->mem_pool, entry->handle, ZS_MM_RO); - if (entry->len == PAGE_SIZE) { - match = !memcmp(mem, cmem, PAGE_SIZE); - } else { - zstrm = zcomp_stream_get(zram->comp); - if (!zcomp_decompress(zstrm, cmem, entry->len, zstrm->buffer)) - match = !memcmp(mem, zstrm->buffer, PAGE_SIZE); - zcomp_stream_put(zram->comp); - } - zs_unmap_object(zram->mem_pool, entry->handle); - - return match; -} - -static unsigned long zram_dedup_put(struct zram *zram, - struct zram_entry *entry) -{ - struct zram_hash *hash; - u32 checksum; - - checksum = entry->checksum; - hash = &zram->hash[checksum % zram->hash_size]; - - spin_lock(&hash->lock); - - entry->refcount--; - if (!entry->refcount) - rb_erase(&entry->rb_node, &hash->rb_root); - else - atomic64_sub(entry->len, &zram->stats.dup_data_size); - - spin_unlock(&hash->lock); - - return entry->refcount; -} - -static struct zram_entry *zram_dedup_get(struct zram *zram, - unsigned char *mem, u32 checksum) -{ - struct zram_hash *hash; - struct zram_entry *entry; - struct rb_node *rb_node; - - hash = &zram->hash[checksum % zram->hash_size]; - - spin_lock(&hash->lock); - rb_node = hash->rb_root.rb_node; - while (rb_node) { - entry = rb_entry(rb_node, struct zram_entry, rb_node); - if (checksum == entry->checksum) { - entry->refcount++; - atomic64_add(entry->len, &zram->stats.dup_data_size); - spin_unlock(&hash->lock); - - if (zram_dedup_match(zram, entry, mem)) - return entry; - - zram_entry_free(zram, entry); - - return NULL; - } - - if (checksum < entry->checksum) - rb_node = rb_node->rb_left; - else - rb_node = rb_node->rb_right; - } - spin_unlock(&hash->lock); - - return NULL; -} - -struct zram_entry *zram_dedup_find(struct zram *zram, struct page *page, - u32 *checksum) -{ - void *mem; - struct zram_entry *entry; - - mem = kmap_atomic(page); - *checksum = zram_dedup_checksum(mem); - - entry = zram_dedup_get(zram, mem, *checksum); - kunmap_atomic(mem); - - return entry; -} - -void zram_dedup_init_entry(struct zram *zram, struct zram_entry *entry, - unsigned long handle, unsigned int len) -{ - entry->handle = handle; - entry->refcount = 1; - entry->len = len; -} - -bool zram_dedup_put_entry(struct zram *zram, struct zram_entry *entry) -{ - if (zram_dedup_put(zram, entry)) - return false; - - return true; -} - -int zram_dedup_init(struct zram *zram, size_t num_pages) -{ - int i; - struct zram_hash *hash; - - zram->hash_size = num_pages >> ZRAM_HASH_SHIFT; - zram->hash_size = min_t(size_t, ZRAM_HASH_SIZE_MAX, zram->hash_size); - zram->hash_size = max_t(size_t, ZRAM_HASH_SIZE_MIN, zram->hash_size); - zram->hash = vzalloc(zram->hash_size * sizeof(struct zram_hash)); - if (!zram->hash) { - pr_err("Error allocating zram entry hash\n"); - return -ENOMEM; - } - - for (i = 0; i < zram->hash_size; i++) { - hash = &zram->hash[i]; - spin_lock_init(&hash->lock); - hash->rb_root = RB_ROOT; - } - - return 0; -} - -void zram_dedup_fini(struct zram *zram) -{ - vfree(zram->hash); - zram->hash = NULL; - zram->hash_size = 0; -} diff --git a/drivers/block/zram/zram_dedup.h b/drivers/block/zram/zram_dedup.h deleted file mode 100644 index ebe6bff6c0da..000000000000 --- a/drivers/block/zram/zram_dedup.h +++ /dev/null @@ -1,22 +0,0 @@ -#ifndef _ZRAM_DEDUP_H_ -#define _ZRAM_DEDUP_H_ - -struct zram; -struct zram_entry; - -u64 zram_dedup_dup_size(struct zram *zram); -u64 zram_dedup_meta_size(struct zram *zram); - -void zram_dedup_insert(struct zram *zram, struct zram_entry *new, - u32 checksum); -struct zram_entry *zram_dedup_find(struct zram *zram, struct page *page, - u32 *checksum); - -void zram_dedup_init_entry(struct zram *zram, struct zram_entry *entry, - unsigned long handle, unsigned int len); -bool zram_dedup_put_entry(struct zram *zram, struct zram_entry *entry); - -int zram_dedup_init(struct zram *zram, size_t num_pages); -void zram_dedup_fini(struct zram *zram); - -#endif /* _ZRAM_DEDUP_H_ */ diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index d756184db86e..a14a8a4696b8 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1074,7 +1074,7 @@ static ssize_t mm_stat_show(struct device *dev, max_used = atomic_long_read(&zram->stats.max_used_pages); ret = scnprintf(buf, PAGE_SIZE, - "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu %8llu\n", + "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu\n", orig_size << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.compr_data_size), mem_used << PAGE_SHIFT, @@ -1082,8 +1082,6 @@ static ssize_t mm_stat_show(struct device *dev, max_used << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.same_pages), pool_stats.pages_compacted, - zram_dedup_dup_size(zram), - zram_dedup_meta_size(zram), (u64)atomic64_read(&zram->stats.huge_pages)); up_read(&zram->init_lock); @@ -1139,34 +1137,26 @@ static struct zram_entry *zram_entry_alloc(struct zram *zram, unsigned int len, gfp_t flags) { struct zram_entry *entry; - unsigned long handle; entry = kzalloc(sizeof(*entry), flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE|__GFP_CMA)); if (!entry) return NULL; - handle = zs_malloc(zram->mem_pool, len, flags); - if (!handle) { + entry->handle = zs_malloc(zram->mem_pool, len, flags); + if (!entry->handle) { kfree(entry); return NULL; } - zram_dedup_init_entry(zram, entry, handle, len); - atomic64_add(sizeof(*entry), &zram->stats.meta_data_size); - return entry; } -void zram_entry_free(struct zram *zram, struct zram_entry *entry) +static inline void zram_entry_free(struct zram *zram, + struct zram_entry *entry) { - if (!zram_dedup_put_entry(zram, entry)) - return; - zs_free(zram->mem_pool, entry->handle); kfree(entry); - - atomic64_sub(sizeof(*entry), &zram->stats.meta_data_size); } static void zram_meta_free(struct zram *zram, u64 disksize) @@ -1179,7 +1169,6 @@ static void zram_meta_free(struct zram *zram, u64 disksize) zram_free_page(zram, index); zs_destroy_pool(zram->mem_pool); - zram_dedup_fini(zram); vfree(zram->table); } @@ -1201,12 +1190,6 @@ static bool zram_meta_alloc(struct zram *zram, u64 disksize) if (!huge_class_size) huge_class_size = zs_huge_class_size(zram->mem_pool); - if (zram_dedup_init(zram, num_pages)) { - vfree(zram->table); - zs_destroy_pool(zram->mem_pool); - return false; - } - return true; } @@ -1366,7 +1349,6 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, void *src, *dst, *mem; struct zcomp_strm *zstrm; struct page *page = bvec->bv_page; - u32 checksum; unsigned long element = 0; enum zram_pageflags flags = 0; @@ -1380,12 +1362,6 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, } kunmap_atomic(mem); - entry = zram_dedup_find(zram, page, &checksum); - if (entry) { - comp_len = entry->len; - goto out; - } - compress_again: zstrm = zcomp_stream_get(zram->comp); src = kmap_atomic(page); @@ -1454,7 +1430,6 @@ compress_again: zcomp_stream_put(zram->comp); zs_unmap_object(zram->mem_pool, entry->handle); atomic64_add(comp_len, &zram->stats.compr_data_size); - zram_dedup_insert(zram, entry, checksum); out: /* * Free memory associated with this sector diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index b56c33c372dc..902b0ce256d0 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -18,10 +18,8 @@ #include #include #include -#include #include "zcomp.h" -#include "zram_dedup.h" #define SECTOR_SHIFT 9 #define SECTORS_PER_PAGE_SHIFT (PAGE_SHIFT - SECTOR_SHIFT) @@ -60,10 +58,6 @@ enum zram_pageflags { /*-- Data structures */ struct zram_entry { - struct rb_node rb_node; - u32 len; - u32 checksum; - unsigned long refcount; unsigned long handle; }; @@ -92,11 +86,6 @@ struct zram_stats { atomic64_t pages_stored; /* no. of pages currently stored */ atomic_long_t max_used_pages; /* no. of maximum pages stored */ atomic64_t writestall; /* no. of write slow paths */ - atomic64_t dup_data_size; /* - * compressed size of pages - * duplicated - */ - atomic64_t meta_data_size; /* size of zram_entries */ atomic64_t miss_free; /* no. of missed free */ #ifdef CONFIG_ZRAM_WRITEBACK atomic64_t bd_count; /* no. of pages in backing device */ @@ -105,18 +94,11 @@ struct zram_stats { #endif }; -struct zram_hash { - spinlock_t lock; - struct rb_root rb_root; -}; - struct zram { struct zram_table_entry *table; struct zs_pool *mem_pool; struct zcomp *comp; struct gendisk *disk; - struct zram_hash *hash; - size_t hash_size; /* Prevent concurrent execution of device init */ struct rw_semaphore init_lock; /* @@ -149,6 +131,4 @@ struct zram { struct dentry *debugfs_dir; #endif }; - -void zram_entry_free(struct zram *zram, struct zram_entry *entry); #endif