Unverified Commit b5cd306b authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!2162 zram: do not waste zram_table_entry flags bits 

Merge Pull Request from: @ci-robot 
 
PR sync from: Jinjiang Tu <tujinjiang@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/B6S7R77B54GR6T3NUCRY7W5C735344PE/ 
 
https://gitee.com/openeuler/kernel/issues/I7TWVA 
 
Link:https://gitee.com/openeuler/kernel/pulls/2162

 

Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 9d26fa52 84f941ba

drivers/block/zram/zram_drv.c

+2 −0
Original line number Diff line number Diff line
@@ -2591,6 +2591,8 @@ static int __init zram_init(void) 
{

	int ret;



	BUILD_BUG_ON(__NR_ZRAM_PAGEFLAGS > BITS_PER_LONG);



	ret = cpuhp_setup_state_multi(CPUHP_ZCOMP_PREPARE, "block/zram:prepare",

				      zcomp_cpu_up_prepare, zcomp_cpu_dead);

	if (ret < 0)

drivers/block/zram/zram_drv.h

+7 −8
Original line number Diff line number Diff line
@@ -30,16 +30,15 @@ 




/*

 * The lower ZRAM_FLAG_SHIFT bits of table.flags is for

 * object size (excluding header), the higher bits is for

 * zram_pageflags.

 * ZRAM is mainly used for memory efficiency so we want to keep memory

 * footprint small and thus squeeze size and zram pageflags into a flags

 * member. The lower ZRAM_FLAG_SHIFT bits is for object size (excluding

 * header), which cannot be larger than PAGE_SIZE (requiring PAGE_SHIFT

 * bits), the higher bits are for zram_pageflags.

 *

 * zram is mainly used for memory efficiency so we want to keep memory

 * footprint small so we can squeeze size and flags into a field.

 * The lower ZRAM_FLAG_SHIFT bits is for object size (excluding header),

 * the higher bits is for zram_pageflags.

 * We use BUILD_BUG_ON() to make sure that zram pageflags don't overflow.

 */

#define ZRAM_FLAG_SHIFT 24

#define ZRAM_FLAG_SHIFT (PAGE_SHIFT + 1)



/* Only 2 bits are allowed for comp priority index */

#define ZRAM_COMP_PRIORITY_MASK	0x3