Now, zram has no feature to limit memory usage even though so that theoretically zram can deplete system memory. In addition, it makes hard to control memory usage of the platform so zram users have asked it several times. This patchset adds the feature. Patch 1 makes zs_get_total_size_bytes faster because it would be used frequently in later patches for the new feature. Patch 2 changes zs_get_total_size_bytes's return unit from bytes to page so that zsmalloc doesn't need unnecessary operation(ie, << PAGE_SHIFT). Patch 3 adds new feature. I added the feature into zram layer, not zsmalloc because limiation is zram's requirement, not zsmalloc so any other user using zsmalloc(ie, zpool) shouldn't affected by unnecessary branch of zsmalloc. In future, if every users of zsmalloc want the feature, then, we could move the feature from client side to zsmalloc easily but vice versa would be painful. Patch 4 adds news facility to report maximum memory usage of zram so that user can get how many of peak memory zram used easily without extremely short inverval polling via /sys/block/zram0/mem_used_total. * From v1 * rebased on next-20140815 * fix up race problem - David, Dan * reset mem_used_max as current total_bytes, rather than 0 - David * resetting works with only "0" write for extensiblilty - David Minchan Kim (4): [1] zsmalloc: move pages_allocated to zs_pool [2] zsmalloc: change return value unit of zs_get_total_size_bytes [3] zram: zram memory size limitation [4] zram: report maximum used memory Documentation/ABI/testing/sysfs-block-zram | 19 ++++++ Documentation/blockdev/zram.txt | 21 ++++-- drivers/block/zram/zram_drv.c | 101 ++++++++++++++++++++++++++++- drivers/block/zram/zram_drv.h | 6 ++ include/linux/zsmalloc.h | 2 +- mm/zsmalloc.c | 38 ++++++----- 6 files changed, 162 insertions(+), 25 deletions(-) -- 2.0.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>