diff options
author | Minchan Kim <minchan@kernel.org> | 2018-12-28 00:36:40 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-28 12:11:49 -0800 |
commit | 7e5292831b346bacb05558ca385cae366187314c (patch) | |
tree | 8326a73a602de333c95f221b26b9b4b3dd430433 /drivers | |
parent | 5547932dc67a48713eece4fa4703bfdf0cfcb818 (diff) |
zram: refactor flags and writeback stuff
Rename some variables and restructure some code for better readability in
writeback and zs_free_page.
Link: http://lkml.kernel.org/r/20181127055429.251614-4-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/block/zram/zram_drv.c | 105 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.h | 8 |
2 files changed, 44 insertions, 69 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index d1459cc1159f..4457d0395bfb 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -55,17 +55,17 @@ static void zram_free_page(struct zram *zram, size_t index); static int zram_slot_trylock(struct zram *zram, u32 index) { - return bit_spin_trylock(ZRAM_LOCK, &zram->table[index].value); + return bit_spin_trylock(ZRAM_LOCK, &zram->table[index].flags); } static void zram_slot_lock(struct zram *zram, u32 index) { - bit_spin_lock(ZRAM_LOCK, &zram->table[index].value); + bit_spin_lock(ZRAM_LOCK, &zram->table[index].flags); } static void zram_slot_unlock(struct zram *zram, u32 index) { - bit_spin_unlock(ZRAM_LOCK, &zram->table[index].value); + bit_spin_unlock(ZRAM_LOCK, &zram->table[index].flags); } static inline bool init_done(struct zram *zram) @@ -76,7 +76,7 @@ static inline bool init_done(struct zram *zram) static inline bool zram_allocated(struct zram *zram, u32 index) { - return (zram->table[index].value >> (ZRAM_FLAG_SHIFT + 1)) || + return (zram->table[index].flags >> (ZRAM_FLAG_SHIFT + 1)) || zram->table[index].handle; } @@ -99,19 +99,19 @@ static void zram_set_handle(struct zram *zram, u32 index, unsigned long handle) static bool zram_test_flag(struct zram *zram, u32 index, enum zram_pageflags flag) { - return zram->table[index].value & BIT(flag); + return zram->table[index].flags & BIT(flag); } static void zram_set_flag(struct zram *zram, u32 index, enum zram_pageflags flag) { - zram->table[index].value |= BIT(flag); + zram->table[index].flags |= BIT(flag); } static void zram_clear_flag(struct zram *zram, u32 index, enum zram_pageflags flag) { - zram->table[index].value &= ~BIT(flag); + zram->table[index].flags &= ~BIT(flag); } static inline void zram_set_element(struct zram *zram, u32 index, @@ -127,15 +127,15 @@ static unsigned long zram_get_element(struct zram *zram, u32 index) static size_t zram_get_obj_size(struct zram *zram, u32 index) { - return zram->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1); + return zram->table[index].flags & (BIT(ZRAM_FLAG_SHIFT) - 1); } static void zram_set_obj_size(struct zram *zram, u32 index, size_t size) { - unsigned long flags = zram->table[index].value >> ZRAM_FLAG_SHIFT; + unsigned long flags = zram->table[index].flags >> ZRAM_FLAG_SHIFT; - zram->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size; + zram->table[index].flags = (flags << ZRAM_FLAG_SHIFT) | size; } #if PAGE_SIZE != 4096 @@ -282,16 +282,11 @@ static ssize_t mem_used_max_store(struct device *dev, } #ifdef CONFIG_ZRAM_WRITEBACK -static bool zram_wb_enabled(struct zram *zram) -{ - return zram->backing_dev; -} - static void reset_bdev(struct zram *zram) { struct block_device *bdev; - if (!zram_wb_enabled(zram)) + if (!zram->backing_dev) return; bdev = zram->bdev; @@ -318,7 +313,7 @@ static ssize_t backing_dev_show(struct device *dev, ssize_t ret; down_read(&zram->init_lock); - if (!zram_wb_enabled(zram)) { + if (!zram->backing_dev) { memcpy(buf, "none\n", 5); up_read(&zram->init_lock); return 5; @@ -447,7 +442,7 @@ out: return err; } -static unsigned long get_entry_bdev(struct zram *zram) +static unsigned long alloc_block_bdev(struct zram *zram) { unsigned long blk_idx = 1; retry: @@ -462,11 +457,11 @@ retry: return blk_idx; } -static void put_entry_bdev(struct zram *zram, unsigned long entry) +static void free_block_bdev(struct zram *zram, unsigned long blk_idx) { int was_set; - was_set = test_and_clear_bit(entry, zram->bitmap); + was_set = test_and_clear_bit(blk_idx, zram->bitmap); WARN_ON_ONCE(!was_set); } @@ -579,7 +574,7 @@ static int write_to_bdev(struct zram *zram, struct bio_vec *bvec, if (!bio) return -ENOMEM; - entry = get_entry_bdev(zram); + entry = alloc_block_bdev(zram); if (!entry) { bio_put(bio); return -ENOSPC; @@ -590,7 +585,7 @@ static int write_to_bdev(struct zram *zram, struct bio_vec *bvec, if (!bio_add_page(bio, bvec->bv_page, bvec->bv_len, bvec->bv_offset)) { bio_put(bio); - put_entry_bdev(zram, entry); + free_block_bdev(zram, entry); return -EIO; } @@ -608,18 +603,7 @@ static int write_to_bdev(struct zram *zram, struct bio_vec *bvec, return 0; } -static void zram_wb_clear(struct zram *zram, u32 index) -{ - unsigned long entry; - - zram_clear_flag(zram, index, ZRAM_WB); - entry = zram_get_element(zram, index); - zram_set_element(zram, index, 0); - put_entry_bdev(zram, entry); -} - #else -static bool zram_wb_enabled(struct zram *zram) { return false; } static inline void reset_bdev(struct zram *zram) {}; static int write_to_bdev(struct zram *zram, struct bio_vec *bvec, u32 index, struct bio *parent, @@ -634,7 +618,8 @@ static int read_from_bdev(struct zram *zram, struct bio_vec *bvec, { return -EIO; } -static void zram_wb_clear(struct zram *zram, u32 index) {} + +static void free_block_bdev(struct zram *zram, unsigned long blk_idx) {}; #endif #ifdef CONFIG_ZRAM_MEMORY_TRACKING @@ -656,11 +641,6 @@ static void zram_accessed(struct zram *zram, u32 index) zram->table[index].ac_time = ktime_get_boottime(); } -static void zram_reset_access(struct zram *zram, u32 index) -{ - zram->table[index].ac_time = 0; -} - static ssize_t read_block_state(struct file *file, char __user *buf, size_t count, loff_t *ppos) { @@ -741,7 +721,6 @@ static void zram_debugfs_unregister(struct zram *zram) static void zram_debugfs_create(void) {}; static void zram_debugfs_destroy(void) {}; static void zram_accessed(struct zram *zram, u32 index) {}; -static void zram_reset_access(struct zram *zram, u32 index) {}; static void zram_debugfs_register(struct zram *zram) {}; static void zram_debugfs_unregister(struct zram *zram) {}; #endif @@ -942,17 +921,18 @@ static void zram_free_page(struct zram *zram, size_t index) { unsigned long handle; - zram_reset_access(zram, index); - +#ifdef CONFIG_ZRAM_MEMORY_TRACKING + zram->table[index].ac_time = 0; +#endif if (zram_test_flag(zram, index, ZRAM_HUGE)) { zram_clear_flag(zram, index, ZRAM_HUGE); atomic64_dec(&zram->stats.huge_pages); } - if (zram_wb_enabled(zram) && zram_test_flag(zram, index, ZRAM_WB)) { - zram_wb_clear(zram, index); - atomic64_dec(&zram->stats.pages_stored); - return; + if (zram_test_flag(zram, index, ZRAM_WB)) { + zram_clear_flag(zram, index, ZRAM_WB); + free_block_bdev(zram, zram_get_element(zram, index)); + goto out; } /* @@ -961,10 +941,8 @@ static void zram_free_page(struct zram *zram, size_t index) */ if (zram_test_flag(zram, index, ZRAM_SAME)) { zram_clear_flag(zram, index, ZRAM_SAME); - zram_set_element(zram, index, 0); atomic64_dec(&zram->stats.same_pages); - atomic64_dec(&zram->stats.pages_stored); - return; + goto out; } handle = zram_get_handle(zram, index); @@ -975,10 +953,11 @@ static void zram_free_page(struct zram *zram, size_t index) atomic64_sub(zram_get_obj_size(zram, index), &zram->stats.compr_data_size); +out: atomic64_dec(&zram->stats.pages_stored); - zram_set_handle(zram, index, 0); zram_set_obj_size(zram, index, 0); + WARN_ON_ONCE(zram->table[index].flags & ~(1UL << ZRAM_LOCK)); } static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, @@ -989,24 +968,20 @@ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, unsigned int size; void *src, *dst; - if (zram_wb_enabled(zram)) { - zram_slot_lock(zram, index); - if (zram_test_flag(zram, index, ZRAM_WB)) { - struct bio_vec bvec; - - zram_slot_unlock(zram, index); + zram_slot_lock(zram, index); + if (zram_test_flag(zram, index, ZRAM_WB)) { + struct bio_vec bvec; - bvec.bv_page = page; - bvec.bv_len = PAGE_SIZE; - bvec.bv_offset = 0; - return read_from_bdev(zram, &bvec, - zram_get_element(zram, index), - bio, partial_io); - } zram_slot_unlock(zram, index); + + bvec.bv_page = page; + bvec.bv_len = PAGE_SIZE; + bvec.bv_offset = 0; + return read_from_bdev(zram, &bvec, + zram_get_element(zram, index), + bio, partial_io); } - zram_slot_lock(zram, index); handle = zram_get_handle(zram, index); if (!handle || zram_test_flag(zram, index, ZRAM_SAME)) { unsigned long value; @@ -1118,7 +1093,7 @@ compress_again: if (unlikely(comp_len >= huge_class_size)) { comp_len = PAGE_SIZE; - if (zram_wb_enabled(zram) && allow_wb) { + if (zram->backing_dev && allow_wb) { zcomp_stream_put(zram->comp); ret = write_to_bdev(zram, bvec, index, bio, &element); if (!ret) { diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index d1095dfdffa8..4f83f1f14b0a 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -30,7 +30,7 @@ /* - * The lower ZRAM_FLAG_SHIFT bits of table.value is for + * The lower ZRAM_FLAG_SHIFT bits of table.flags is for * object size (excluding header), the higher bits is for * zram_pageflags. * @@ -41,7 +41,7 @@ */ #define ZRAM_FLAG_SHIFT 24 -/* Flags for zram pages (table[page_no].value) */ +/* Flags for zram pages (table[page_no].flags) */ enum zram_pageflags { /* zram slot is locked */ ZRAM_LOCK = ZRAM_FLAG_SHIFT, @@ -60,7 +60,7 @@ struct zram_table_entry { unsigned long handle; unsigned long element; }; - unsigned long value; + unsigned long flags; #ifdef CONFIG_ZRAM_MEMORY_TRACKING ktime_t ac_time; #endif @@ -105,8 +105,8 @@ struct zram { * zram is claimed so open request will be failed */ bool claim; /* Protected by bdev->bd_mutex */ -#ifdef CONFIG_ZRAM_WRITEBACK struct file *backing_dev; +#ifdef CONFIG_ZRAM_WRITEBACK struct block_device *bdev; unsigned int old_block_size; unsigned long *bitmap; |