xavi/android_kernel_m2note/Documentation/ABI/testing, branch ng-7.1.2

Finally eradicate CONFIG_HOTPLUG

2017-12-22T15:23:46+00:00

Ever since commit 45f035ab9b8f ("CONFIG_HOTPLUG should be always on"), it has been basically impossible to build a kernel with CONFIG_HOTPLUG turned off. Remove all the remaining references to it. Cc: Russell King Cc: Doug Thompson Cc: Bjorn Helgaas Cc: Steven Whitehouse Cc: Arnd Bergmann Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Andrew Morton Signed-off-by: Stephen Rothwell Acked-by: Mauro Carvalho Chehab Acked-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

f2fs: introduce gc_urgent mode for background GC

2017-10-04T13:32:45+00:00

This patch adds a sysfs entry to control urgent mode for background GC. If this is set, background GC thread conducts GC with gc_urgent_sleep_time all the time. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

zram: introduce per-device debug_stat sysfs node

2017-09-25T19:16:39+00:00

debug_stat sysfs is read-only and represents various debugging data that zram developers may need. This file is not meant to be used by anyone else: its content is not documented and will change any time w/o any notice. Therefore, the output of debug_stat file contains a version string. To avoid any confusion, we will increase the version number every time we modify the output. At the moment this file exports only one value -- the number of re-compressions, IOW, the number of times compression fast path has failed. This stat is temporary any will be useful in case if any per-cpu compression streams regressions will be reported. Link: http://lkml.kernel.org/r/20160513230834.GB26763@bbox Link: http://lkml.kernel.org/r/20160511134553.12655-1-sergey.senozhatsky@gmail.com Signed-off-by: Sergey Senozhatsky Signed-off-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zram: add dynamic device add/remove functionality

2017-09-25T18:40:42+00:00

We currently don't support on-demand device creation. The one and only way to have N zram devices is to specify num_devices module parameter (default value: 1). IOW if, for some reason, at some point, user wants to have N + 1 devies he/she must umount all the existing devices, unload the module, load the module passing num_devices equals to N + 1. And do this again, if needed. This patch introduces zram control sysfs class, which has two sysfs attrs: - hot_add -- add a new zram device - hot_remove -- remove a specific (device_id) zram device hot_add sysfs attr is read-only and has only automatic device id assignment mode (as requested by Minchan Kim). read operation performed on this attr creates a new zram device and returns back its device_id or error status. Usage example: # add a new specific zram device cat /sys/class/zram-control/hot_add 2 # remove a specific zram device echo 4 > /sys/class/zram-control/hot_remove Returning zram_add() error code back to user (-ENOMEM in this case) cat /sys/class/zram-control/hot_add cat: /sys/class/zram-control/hot_add: Cannot allocate memory NOTE, there might be users who already depend on the fact that at least zram0 device gets always created by zram_init(). Preserve this behavior. [minchan@kernel.org: use zram->claim to avoid lockdep splat] Signed-off-by: Sergey Senozhatsky Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block: zram: Backport from Linux 4.1

2017-09-25T18:26:59+00:00

Change-Id: I23f6f75979077992298d848efd79a6efc0d776bd

FROMLIST: f2fs: introduce discard_granularity sysfs entry

2017-09-08T11:50:22+00:00

(url: https://patchwork.kernel.org/patch/9876921/) Commit d618ebaf0aa8 ("f2fs: enable small discard by default") enables f2fs to issue 4K size discard in real-time discard mode. However, issuing smaller discard may cost more lifetime but releasing less free space in flash device. Since f2fs has ability of separating hot/cold data and garbage collection, we can expect that small-sized invalid region would expand soon with OPU, deletion or garbage collection on valid datas, so it's better to delay or skip issuing smaller size discards, it could help to reduce overmuch consumption of IO bandwidth and lifetime of flash storage. This patch makes f2fs selectng 64K size as its default minimal granularity, and issue discard with the size which is not smaller than minimal granularity. Also it exposes discard granularity as sysfs entry for configuration in different scenario. Jaegeuk Kim: We must issue all the accumulated discard commands when fstrim is called. So, I've added pend_list_tag[] to indicate whether we should issue the commands or not. If tag sets P_ACTIVE or P_TRIM, we have to issue them. P_TRIM is set once at a time, given fstrim trigger. In addition, issue_discard_thread is calling too much due to the number of discard commands remaining in the pending list. I added a timer to control it likewise gc_thread. Change-Id: Ia90dd686c25cb27f144137ea3c9bcc1c943a9aea Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: introduce reserved_blocks in sysfs

2017-07-21T10:38:06+00:00

In this patch, we add a new sysfs interface, with it, we can control number of reserved blocks in system which could not be used by user, it enable f2fs to let user to configure for adjusting over-provision ratio dynamically instead of changing it by mkfs. So we can expect it will help to reserve more free space for relieving GC in both filesystem and flash device. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Conflicts: Documentation/ABI/testing/sysfs-fs-f2fs

f2fs: introduce lifetime write IO statistics

2017-04-13T10:32:56+00:00

This patch introduces lifetime IO write statistics exposed to the sysfs interface. The write IO amount is obtained from block layer, accumulated in the file system and stored in the hot node summary of checkpoint. Signed-off-by: Shuoran Liu Signed-off-by: Pengyang Hou [Jaegeuk Kim: add sysfs documentation] Signed-off-by: Jaegeuk Kim

f2fs: export dirty_nats_ratio in sysfs

2017-04-13T10:32:50+00:00

This patch exports a new sysfs entry 'dirty_nat_ratio' to control threshold of dirty nat entries, if current ratio exceeds configured threshold, checkpoint will be triggered in f2fs_balance_fs_bg for flushing dirty nats. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Conflicts: Documentation/ABI/testing/sysfs-fs-f2fs

f2fs: detect idle time depending on user behavior

2017-04-13T10:32:49+00:00

This patch adds last time that user requested filesystem operations. This information is used to detect whether system is idle or not later. Signed-off-by: Jaegeuk Kim Conflicts: Documentation/ABI/testing/sysfs-fs-f2fs