diff options
| author | Minchan Kim <minchan@kernel.org> | 2019-01-08 15:22:53 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-08 17:15:10 -0800 |
| commit | 1d69a3f8ae77e3dbfdc1356225cce5ea9c366aec (patch) | |
| tree | 6e070457b08c54a2ed09d66c81ecc8227e7d4e9b /Documentation/ABI | |
| parent | 3bd6e94bec122a951d462c239b47954cf5f36e33 (diff) | |
zram: idle writeback fixes and cleanup
This patch includes some fixes and cleanup for idle-page writeback.
1. writeback_limit interface
Now writeback_limit interface is rather conusing. For example, once
writeback limit budget is exausted, admin can see 0 from
/sys/block/zramX/writeback_limit which is same semantic with disable
writeback_limit at this moment. IOW, admin cannot tell that zero came
from disable writeback limit or exausted writeback limit.
To make the interface clear, let's sepatate enable of writeback limit to
another knob - /sys/block/zram0/writeback_limit_enable
* before:
while true :
# to re-enable writeback limit once previous one is used up
echo 0 > /sys/block/zram0/writeback_limit
echo $((200<<20)) > /sys/block/zram0/writeback_limit
..
.. # used up the writeback limit budget
* new
# To enable writeback limit, from the beginning, admin should
# enable it.
echo $((200<<20)) > /sys/block/zram0/writeback_limit
echo 1 > /sys/block/zram/0/writeback_limit_enable
while true :
echo $((200<<20)) > /sys/block/zram0/writeback_limit
..
.. # used up the writeback limit budget
It's much strightforward.
2. fix condition check idle/huge writeback mode check
The mode in writeback_store is not bit opeartion any more so no need to
use bit operations. Furthermore, current condition check is broken in
that it does writeback every pages regardless of huge/idle.
3. clean up idle_store
No need to use goto.
[minchan@kernel.org: missed spin_lock_init]
Link: http://lkml.kernel.org/r/20190103001601.GA255139@google.com
Link: http://lkml.kernel.org/r/20181224033529.19450-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Suggested-by: John Dias <joaodias@google.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: John Dias <joaodias@google.com>
Cc: Srinivas Paladugu <srnvs@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block-zram | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram index 9d2339a485c8..14b2bf2e5105 100644 --- a/Documentation/ABI/testing/sysfs-block-zram +++ b/Documentation/ABI/testing/sysfs-block-zram @@ -122,11 +122,18 @@ Description: statistics (bd_count, bd_reads, bd_writes) in a format similar to block layer statistics file format. +What: /sys/block/zram<id>/writeback_limit_enable +Date: November 2018 +Contact: Minchan Kim <minchan@kernel.org> +Description: + The writeback_limit_enable file is read-write and specifies + eanbe of writeback_limit feature. "1" means eable the feature. + No limit "0" is the initial state. + What: /sys/block/zram<id>/writeback_limit Date: November 2018 Contact: Minchan Kim <minchan@kernel.org> Description: The writeback_limit file is read-write and specifies the maximum amount of writeback ZRAM can do. The limit could be changed - in run time and "0" means disable the limit. - No limit is the initial state. + in run time. |