__zram_bvec_write has some of duplicated logic for zram meta data handling of same_page|compressed_page. This patch aims to clean it up without behavior change.
Link: http://lkml.kernel.org/r/1496019048-27016-1-git-send-email-minc...@kernel.org Signed-off-by: Minchan Kim <minc...@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhat...@gmail.com> --- drivers/block/zram/zram_drv.c | 55 +++++++++++++++++-------------------------- 1 file changed, 22 insertions(+), 33 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index d3e3af2..5d3ea405 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -453,30 +453,6 @@ static bool zram_same_page_read(struct zram *zram, u32 index, return false; } -static bool zram_same_page_write(struct zram *zram, u32 index, - struct page *page) -{ - unsigned long element; - void *mem = kmap_atomic(page); - - if (page_same_filled(mem, &element)) { - kunmap_atomic(mem); - /* Free memory associated with this sector now. */ - zram_slot_lock(zram, index); - zram_free_page(zram, index); - zram_set_flag(zram, index, ZRAM_SAME); - zram_set_element(zram, index, element); - zram_slot_unlock(zram, index); - - atomic64_inc(&zram->stats.same_pages); - atomic64_inc(&zram->stats.pages_stored); - return true; - } - kunmap_atomic(mem); - - return false; -} - static void zram_meta_free(struct zram *zram, u64 disksize) { size_t num_pages = disksize >> PAGE_SHIFT; @@ -685,14 +661,23 @@ static int zram_compress(struct zram *zram, struct zcomp_strm **zstrm, static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index) { int ret; - unsigned long handle; - unsigned int comp_len; - void *src, *dst; + unsigned long handle = 0; + unsigned int comp_len = 0; + void *src, *dst, *mem; struct zcomp_strm *zstrm; struct page *page = bvec->bv_page; + unsigned long element = 0; + enum zram_pageflags flags = 0; - if (zram_same_page_write(zram, index, page)) - return 0; + mem = kmap_atomic(page); + if (page_same_filled(mem, &element)) { + kunmap_atomic(mem); + /* Free memory associated with this sector now */ + atomic64_inc(&zram->stats.same_pages); + flags = ZRAM_SAME; + goto out; + } + kunmap_atomic(mem); zstrm = zcomp_stream_get(zram->comp); ret = zram_compress(zram, &zstrm, page, &handle, &comp_len); @@ -712,19 +697,23 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index) zcomp_stream_put(zram->comp); zs_unmap_object(zram->mem_pool, handle); - +out: /* * Free memory associated with this sector * before overwriting unused sectors. */ zram_slot_lock(zram, index); zram_free_page(zram, index); - zram_set_handle(zram, index, handle); - zram_set_obj_size(zram, index, comp_len); + if (flags == ZRAM_SAME) { + zram_set_flag(zram, index, ZRAM_SAME); + zram_set_element(zram, index, element); + } else { + zram_set_handle(zram, index, handle); + zram_set_obj_size(zram, index, comp_len); + } zram_slot_unlock(zram, index); /* Update stats */ - atomic64_add(comp_len, &zram->stats.compr_data_size); atomic64_inc(&zram->stats.pages_stored); return 0; } -- 2.7.4
