Commit 346658a5 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'docs-5.18' of git://git.lwn.net/linux 

Pull documentation updates from Jonathan Corbet:
 "It has been a moderately busy cycle for documentation; some of the
  highlights are:

   - Numerous PDF-generation improvements

   - Kees's new document with guidelines for researchers studying the
     development community.

   - The ongoing stream of Chinese translations

   - Thorsten's new document on regression handling

   - A major reworking of the internal documentation for the kernel-doc
     script.

  Plus the usual stream of typo fixes and such"

* tag 'docs-5.18' of git://git.lwn.net/linux: (80 commits)
  docs/kernel-parameters: update description of mem=
  docs/zh_CN: Add sched-nice-design Chinese translation
  docs: scheduler: Convert schedutil.txt to ReST
  Docs: ktap: add code-block type
  docs: serial: fix a reference file name in driver.rst
  docs: UML: Mention telnetd for port channel
  docs/zh_CN: add damon reclaim translation
  docs/zh_CN: add damon usage translation
  docs/zh_CN: add admin-guide damon start translation
  docs/zh_CN: add admin-guide damon index translation
  docs/zh_CN: Refactoring the admin-guide directory index
  zh_CN: Add translation for admin-guide/mm/index.rst
  zh_CN: Add translations for admin-guide/mm/ksm.rst
  Add Chinese translation for vm/ksm.rst
  docs/zh_CN: Add sched-stats Chinese translation
  docs/zh_CN: add devicetree of_unittest translation
  docs/zh_CN: add devicetree usage-model translation
  docs/zh_CN: add devicetree index translation
  Documentation: describe how to apply incremental stable patches
  docs/zh_CN: add peci subsystem translation
  ...
parents d2eb5500 75c05fab

Documentation/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -26,7 +26,7 @@ SPHINX_CONF = conf.py 
PAPER         =

BUILDDIR      = $(obj)/output

PDFLATEX      = xelatex

LATEXOPTS     = -interaction=batchmode

LATEXOPTS     = -interaction=batchmode -no-shell-escape



ifeq ($(KBUILD_VERBOSE),0)

SPHINXOPTS    += "-q"

Documentation/admin-guide/blockdev/zram.rst

+10 −10
Original line number Diff line number Diff line
@@ -315,8 +315,8 @@ To use the feature, admin should set up backing device via:: 


	echo /dev/sda5 > /sys/block/zramX/backing_dev



before disksize setting. It supports only partition at this moment.

If admin wants to use incompressible page writeback, they could do via::

before disksize setting. It supports only partitions at this moment.

If admin wants to use incompressible page writeback, they could do it via::



	echo huge > /sys/block/zramX/writeback
@@ -341,9 +341,9 @@ Admin can request writeback of those idle pages at right timing via:: 


	echo idle > /sys/block/zramX/writeback



With the command, zram writeback idle pages from memory to the storage.

With the command, zram will writeback idle pages from memory to the storage.



If admin want to write a specific page in zram device to backing device,

If an admin wants to write a specific page in zram device to the backing device,

they could write a page index into the interface.



	echo "page_index=1251" > /sys/block/zramX/writeback
@@ -354,7 +354,7 @@ to guarantee storage health for entire product life. 


To overcome the concern, zram supports "writeback_limit" feature.

The "writeback_limit_enable"'s default value is 0 so that it doesn't limit

any writeback. IOW, if admin wants to apply writeback budget, he should

any writeback. IOW, if admin wants to apply writeback budget, they should

enable writeback_limit_enable via::



	$ echo 1 > /sys/block/zramX/writeback_limit_enable
@@ -365,7 +365,7 @@ until admin sets the budget via /sys/block/zramX/writeback_limit. 
(If admin doesn't enable writeback_limit_enable, writeback_limit's value

assigned via /sys/block/zramX/writeback_limit is meaningless.)



If admin want to limit writeback as per-day 400M, he could do it

If admin wants to limit writeback as per-day 400M, they could do it

like below::



	$ MB_SHIFT=20
@@ -375,16 +375,16 @@ like below:: 
	$ echo 1 > /sys/block/zram0/writeback_limit_enable



If admins want to allow further write again once the budget is exhausted,

he could do it like below::

they could do it like below::



	$ echo $((400<<MB_SHIFT>>4K_SHIFT)) > \

		/sys/block/zram0/writeback_limit



If admin wants to see remaining writeback budget since last set::

If an admin wants to see the remaining writeback budget since last set::



	$ cat /sys/block/zramX/writeback_limit



If admin want to disable writeback limit, he could do::

If an admin wants to disable writeback limit, they could do::



	$ echo 0 > /sys/block/zramX/writeback_limit_enable
@@ -393,7 +393,7 @@ system reboot, echo 1 > /sys/block/zramX/reset) so keeping how many of 
writeback happened until you reset the zram to allocate extra writeback

budget in next setting is user's job.



If admin wants to measure writeback count in a certain period, he could

If admin wants to measure writeback count in a certain period, they could

know it via /sys/block/zram0/bd_stat's 3rd column.



memory tracking

Documentation/admin-guide/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -35,6 +35,7 @@ problems and bugs in particular. 
   :maxdepth: 1



   reporting-issues

   reporting-regressions

   security-bugs

   bug-hunting

   bug-bisect

Documentation/admin-guide/iostats.rst

+3 −3
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ Field 3 -- # of sectors read (unsigned long) 


Field  4 -- # of milliseconds spent reading (unsigned int)

    This is the total number of milliseconds spent by all reads (as

    measured from __make_request() to end_that_request_last()).

    measured from blk_mq_alloc_request() to __blk_mq_end_request()).



Field  5 -- # of writes completed (unsigned long)

    This is the total number of writes completed successfully.
@@ -89,7 +89,7 @@ Field 7 -- # of sectors written (unsigned long) 


Field  8 -- # of milliseconds spent writing (unsigned int)

    This is the total number of milliseconds spent by all writes (as

    measured from __make_request() to end_that_request_last()).

    measured from blk_mq_alloc_request() to __blk_mq_end_request()).



Field  9 -- # of I/Os currently in progress (unsigned int)

    The only field that should go to zero. Incremented as requests are
@@ -120,7 +120,7 @@ Field 14 -- # of sectors discarded (unsigned long) 


Field 15 -- # of milliseconds spent discarding (unsigned int)

    This is the total number of milliseconds spent by all discards (as

    measured from __make_request() to end_that_request_last()).

    measured from blk_mq_alloc_request() to __blk_mq_end_request()).



Field 16 -- # of flush requests completed

    This is the total number of flush requests completed successfully.

Documentation/admin-guide/kernel-parameters.txt

+18 −0
Original line number Diff line number Diff line
@@ -2827,6 +2827,9 @@ 


			For details see: Documentation/admin-guide/hw-vuln/mds.rst



	mem=nn[KMG]	[HEXAGON] Set the memory size.

			Must be specified, otherwise memory size will be 0.



	mem=nn[KMG]	[KNL,BOOT] Force usage of a specific amount of memory

			Amount of memory to be used in cases as follows:
@@ -2834,6 +2837,13 @@ 
			2 when the kernel is not able to see the whole system memory;

			3 memory that lies after 'mem=' boundary is excluded from

			 the hypervisor, then assigned to KVM guests.

			4 to limit the memory available for kdump kernel.



			[ARC,MICROBLAZE] - the limit applies only to low memory,

			high memory is not affected.



			[ARM64] - only limits memory covered by the linear

			mapping. The NOMAP regions are not affected.



			[X86] Work as limiting max address. Use together

			with memmap= to avoid physical address space collisions.
@@ -2844,6 +2854,14 @@ 
			in above case 3, memory may need be hot added after boot

			if system memory of hypervisor is not sufficient.



	mem=nn[KMG]@ss[KMG]

			[ARM,MIPS] - override the memory layout reported by

			firmware.

			Define a memory region of size nn[KMG] starting at

			ss[KMG].

			Multiple different regions can be specified with

			multiple mem= parameters on the command line.



	mem=nopentium	[BUGS=X86-32] Disable usage of 4MB pages for kernel

			memory.