Commit Graph

1795 Commits

Author SHA1 Message Date
Mel Gorman
bbbecb35a4 mm/page_alloc: delete vm.percpu_pagelist_fraction
Patch series "Calculate pcp->high based on zone sizes and active CPUs", v2.

The per-cpu page allocator (PCP) is meant to reduce contention on the zone
lock but the sizing of batch and high is archaic and neither takes the
zone size into account or the number of CPUs local to a zone.  With larger
zones and more CPUs per node, the contention is getting worse.
Furthermore, the fact that vm.percpu_pagelist_fraction adjusts both batch
and high values means that the sysctl can reduce zone lock contention but
also increase allocation latencies.

This series disassociates pcp->high from pcp->batch and then scales
pcp->high based on the size of the local zone with limited impact to
reclaim and accounting for active CPUs but leaves pcp->batch static.  It
also adapts the number of pages that can be on the pcp list based on
recent freeing patterns.

The motivation is partially to adjust to larger memory sizes but is also
driven by the fact that large batches of page freeing via release_pages()
often shows zone contention as a major part of the problem.  Another is a
bug report based on an older kernel where a multi-terabyte process can
takes several minutes to exit.  A workaround was to use
vm.percpu_pagelist_fraction to increase the pcp->high value but testing
indicated that a production workload could not use the same values because
of an increase in allocation latencies.  Unfortunately, I cannot reproduce
this test case myself as the multi-terabyte machines are in active use but
it should alleviate the problem.

The series aims to address both and partially acts as a pre-requisite.
pcp only works with order-0 which is useless for SLUB (when using high
orders) and THP (unconditionally).  To store high-order pages on PCP, the
pcp->high values need to be increased first.

This patch (of 6):

The vm.percpu_pagelist_fraction is used to increase the batch and high
limits for the per-cpu page allocator (PCP).  The intent behind the sysctl
is to reduce zone lock acquisition when allocating/freeing pages but it
has a problem.  While it can decrease contention, it can also increase
latency on the allocation side due to unreasonably large batch sizes.
This leads to games where an administrator adjusts
percpu_pagelist_fraction on the fly to work around contention and
allocation latency problems.

This series aims to alleviate the problems with zone lock contention while
avoiding the allocation-side latency problems.  For the purposes of
review, it's easier to remove this sysctl now and reintroduce a similar
sysctl later in the series that deals only with pcp->high.

Link: https://lkml.kernel.org/r/20210525080119.5455-1-mgorman@techsingularity.net
Link: https://lkml.kernel.org/r/20210525080119.5455-2-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:54 -07:00
Gavin Shan
f58780a8e3 mm/page_reporting: export reporting order as module parameter
The macro PAGE_REPORTING_MIN_ORDER is defined as the page reporting
threshold.  It can't be adjusted at runtime.

This introduces a variable (@page_reporting_order) to replace the marcro
(PAGE_REPORTING_MIN_ORDER).  MAX_ORDER is assigned to it initially,
meaning the page reporting is disabled.  It will be specified by driver if
valid one is provided.  Otherwise, it will fall back to @pageblock_order.
It's also exported so that the page reporting order can be adjusted at
runtime.

Link: https://lkml.kernel.org/r/20210625014710.42954-3-gshan@redhat.com
Signed-off-by: Gavin Shan <gshan@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:47 -07:00
Wang Qing
256f7a6791 doc: watchdog: modify the doc related to "watchdog/%u"
"watchdog/%u" threads has be replaced by cpu_stop_work.  The current
description is extremely misleading.

Link: https://lkml.kernel.org/r/1619687073-24686-5-git-send-email-wangqing@vivo.com
Signed-off-by: Wang Qing <wangqing@vivo.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@canonical.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Qais Yousef <qais.yousef@arm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Santosh Sivaraj <santosh@fossix.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:46 -07:00
Wang Qing
e55fda8cdc doc: watchdog: modify the explanation related to watchdog thread
"watchdog/%u" threads has be replaced by cpu_stop_work.  The current
description is extremely misleading.

Link: https://lkml.kernel.org/r/1619687073-24686-4-git-send-email-wangqing@vivo.com
Signed-off-by: Wang Qing <wangqing@vivo.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@canonical.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Qais Yousef <qais.yousef@arm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Santosh Sivaraj <santosh@fossix.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:46 -07:00
Rafael J. Wysocki
ed562d280c Merge branches 'pm-cpufreq' and 'pm-cpuidle'
* pm-cpufreq:
  cpufreq: Make cpufreq_online() call driver->offline() on errors
  cpufreq: loongson2: Remove unused linux/sched.h headers
  cpufreq: sh: Remove unused linux/sched.h headers
  cpufreq: stats: Clean up local variable in cpufreq_stats_create_table()
  cpufreq: intel_pstate: hybrid: Fix build with CONFIG_ACPI unset
  cpufreq: sc520_freq: add 'fallthrough' to one case
  cpufreq: intel_pstate: Add Cometlake support in no-HWP mode
  cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode
  cpufreq: intel_pstate: hybrid: CPU-specific scaling factor
  cpufreq: intel_pstate: hybrid: Avoid exposing two global attributes

* pm-cpuidle:
  cpuidle: teo: remove unneeded semicolon in teo_select()
  cpuidle: teo: Use kerneldoc documentation in admin-guide
  cpuidle: teo: Rework most recent idle duration values treatment
  cpuidle: teo: Change the main idle state selection logic
  cpuidle: teo: Cosmetic modification of teo_select()
  cpuidle: teo: Cosmetic modifications of teo_update()
  intel_idle: Adjust the SKX C6 parameters if PC6 is disabled
2021-06-29 15:53:07 +02:00
Linus Torvalds
07bdc0746a Merge tag 'pstore-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore updates from Kees Cook:
 "Use normal block device I/O path for pstore/blk. (Christoph Hellwig,
  Kees Cook, Pu Lehui)"

* tag 'pstore-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore/blk: Include zone in pstore_device_info
  pstore/blk: Fix kerndoc and redundancy on blkdev param
  pstore/blk: Use the normal block device I/O path
  pstore/blk: Move verify_size() macro out of function
  pstore/blk: Improve failure reporting
2021-06-28 19:57:00 -07:00
Linus Torvalds
233a806b00 Merge tag 'docs-5.14' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "This was a reasonably active cycle for documentation; this includes:

   - Some kernel-doc cleanups. That script is still regex onslaught from
     hell, but it has gotten a little better.

   - Improvements to the checkpatch docs, which are also used by the
     tool itself.

   - A major update to the pathname lookup documentation.

   - Elimination of :doc: markup, since our automarkup magic can create
     references from filenames without all the extra noise.

   - The flurry of Chinese translation activity continues.

  Plus, of course, the usual collection of updates, typo fixes, and
  warning fixes"

* tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits)
  docs: path-lookup: use bare function() rather than literals
  docs: path-lookup: update symlink description
  docs: path-lookup: update get_link() ->follow_link description
  docs: path-lookup: update WALK_GET, WALK_PUT desc
  docs: path-lookup: no get_link()
  docs: path-lookup: update i_op->put_link and cookie description
  docs: path-lookup: i_op->follow_link replaced with i_op->get_link
  docs: path-lookup: Add macro name to symlink limit description
  docs: path-lookup: remove filename_mountpoint
  docs: path-lookup: update do_last() part
  docs: path-lookup: update path_mountpoint() part
  docs: path-lookup: update path_to_nameidata() part
  docs: path-lookup: update follow_managed() part
  docs: Makefile: Use CONFIG_SHELL not SHELL
  docs: Take a little noise out of the build process
  docs: x86: avoid using ReST :doc:`foo` markup
  docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup
  docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup
  docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup
  docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup
  ...
2021-06-28 16:53:05 -07:00
Linus Torvalds
31e798fd6f Merge tag 'media/v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:

 - V4L2 core control API was split into separate files

 - New RC maps: tango and tc-90405

 - Hantro driver got support for G2/HEVC decoder

 - av7710 is moving to staging, together with some legacy APIs

 - several cleanups related to compat_ioctl32 code

 - Move the MPEG-2 stateless control type out of staging

 - Address several issues with RPM get logic on media drivers

 - Lots of cleanups, bug fixes and improvements.

* tag 'media/v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (394 commits)
  media: s5p-mfc: Fix display delay control creation
  media: mtk-vpu: on suspend, read/write regs only if vpu is running
  media: video-mux: Skip dangling endpoints
  media: Fix Media Controller API config checks
  media: i2c: rdacm20: Re-work ov10635 reset
  media: i2c: rdacm20: Check return values
  media: i2c: rdacm20: Report camera module name
  media: i2c: rdacm20: Enable noise immunity
  media: i2c: rdacm20: Embed 'serializer' field
  media: i2c: rdacm21: Power up OV10640 before OV490
  media: i2c: rdacm21: Fix OV10640 powerup
  media: i2c: rdacm21: Add delay after OV490 reset
  media: i2c: max9271: Introduce wake_up() function
  media: i2c: max9271: Check max9271_write() return
  media: i2c: max9286: Rework comments in .bound()
  media: i2c: max9286: Define high channel amplitude
  media: i2c: max9286: Cache channel amplitude
  media: i2c: max9286: Rename reverse_channel_mv
  media: i2c: max9286: Adjust parameters indent
  media: hantro: add support for Rockchip RK3036
  ...
2021-06-28 15:49:58 -07:00
Mikulas Patocka
5c0de3d72f dm writecache: make writeback pause configurable
Commit 95b88f4d71 ("dm writecache: pause
writeback if cache full and origin being written directly") introduced a
code that pauses cache flushing if we are issuing writes directly to the
origin.

Improve that initial commit by making the timeout code configurable
(via the option "pause_writeback"). Also change the default from 1s to
3s because it performed better.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-28 16:30:13 -04:00
Linus Torvalds
1b1cf8fe99 Merge tag 'x86-splitlock-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 splitlock updates from Ingo Molnar:

 - Add the "ratelimit:N" parameter to the split_lock_detect= boot
   option, to rate-limit the generation of bus-lock exceptions.

   This is both easier on system resources and kinder to offending
   applications than the current policy of outright killing them.

 - Document the split-lock detection feature and its parameters.

* tag 'x86-splitlock-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/x86: Add ratelimit in buslock.rst
  Documentation/admin-guide: Add bus lock ratelimit
  x86/bus_lock: Set rate limit for bus lock
  Documentation/x86: Add buslock.rst
2021-06-28 13:30:02 -07:00
Linus Torvalds
8e4d7a78f0 Merge tag 'x86-cleanups-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups & removal of obsolete code"

* tag 'x86-cleanups-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Correct kernel-doc's arg name in sgx_encl_release()
  doc: Remove references to IBM Calgary
  x86/setup: Document that Windows reserves the first MiB
  x86/crash: Remove crash_reserve_low_1M()
  x86/setup: Remove CONFIG_X86_RESERVE_LOW and reservelow= options
  x86/alternative: Align insn bytes vertically
  x86: Fix leftover comment typos
  x86/asm: Simplify __smp_mb() definition
  x86/alternatives: Make the x86nops[] symbol static
2021-06-28 13:10:25 -07:00
Mikulas Patocka
611c3e168b dm writecache: add optional "metadata_only" parameter
Add a "metadata_only" parameter that when present: only metadata is
promoted to the cache. This option improves performance for heavier
REQ_META workloads (e.g. device-mapper-test-suite's "git clone and
checkout" benchmark improves from 341s to 312s).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25 15:25:21 -04:00
Mike Snitzer
cd039afa0a dm writecache: add "cleaner" and "max_age" to Documentation
Backfill missing Documentation.

Fixes: 93de44eb3f ("dm writecache: implement the "cleaner" policy")
Fixes: 3923d4854e ("dm writecache: implement gradual cleanup")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25 15:25:19 -04:00
Joerg Roedel
2b9d8e3e9a Merge branches 'iommu/fixes', 'arm/rockchip', 'arm/smmu', 'x86/vt-d', 'x86/amd', 'virtio' and 'core' into next 2021-06-25 15:23:25 +02:00
Paul E. McKenney
1253b9b87e clocksource: Provide kernel module to test clocksource watchdog
When the clocksource watchdog marks a clock as unstable, this might
be due to that clock being unstable or it might be due to delays that
happen to occur between the reads of the two clocks.  It would be good
to have a way of testing the clocksource watchdog's ability to
distinguish between these two causes of clock skew and instability.

Therefore, provide a new clocksource-wdtest module selected by a new
TEST_CLOCKSOURCE_WATCHDOG Kconfig option.  This module has a single module
parameter named "holdoff" that provides the number of seconds of delay
before testing should start, which defaults to zero when built as a module
and to 10 seconds when built directly into the kernel.  Very large systems
that boot slowly may need to increase the value of this module parameter.

This module uses hand-crafted clocksource structures to do its testing,
thus avoiding messing up timing for the rest of the kernel and for user
applications.  This module first verifies that the ->uncertainty_margin
field of the clocksource structures are set sanely.  It then tests the
delay-detection capability of the clocksource watchdog, increasing the
number of consecutive delays injected, first provoking console messages
complaining about the delays and finally forcing a clock-skew event.
Unexpected test results cause at least one WARN_ON_ONCE() console splat.
If there are no splats, the test has passed.  Finally, it fuzzes the
value returned from a clocksource to test the clocksource watchdog's
ability to detect time skew.

This module checks the state of its clocksource after each test, and
uses WARN_ON_ONCE() to emit a console splat if there are any failures.
This should enable all types of test frameworks to detect any such
failures.

This facility is intended for diagnostic use only, and should be avoided
on production systems.

Reported-by: Chris Mason <clm@fb.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Feng Tang <feng.tang@intel.com>
Link: https://lore.kernel.org/r/20210527190124.440372-5-paulmck@kernel.org
2021-06-22 16:53:17 +02:00
Paul E. McKenney
fa218f1cce clocksource: Limit number of CPUs checked for clock synchronization
Currently, if skew is detected on a clock marked CLOCK_SOURCE_VERIFY_PERCPU,
that clock is checked on all CPUs.  This is thorough, but might not be
what you want on a system with a few tens of CPUs, let alone a few hundred
of them.

Therefore, by default check only up to eight randomly chosen CPUs.  Also
provide a new clocksource.verify_n_cpus kernel boot parameter.  A value of
-1 says to check all of the CPUs, and a non-negative value says to randomly
select that number of CPUs, without concern about selecting the same CPU
multiple times.  However, make use of a cpumask so that a given CPU will be
checked at most once.

Suggested-by: Thomas Gleixner <tglx@linutronix.de> # For verify_n_cpus=1.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Feng Tang <feng.tang@intel.com>
Link: https://lore.kernel.org/r/20210527190124.440372-3-paulmck@kernel.org
2021-06-22 16:53:16 +02:00
Paul E. McKenney
db3a34e174 clocksource: Retry clock read if long delays detected
When the clocksource watchdog marks a clock as unstable, this might be due
to that clock being unstable or it might be due to delays that happen to
occur between the reads of the two clocks.  Yes, interrupts are disabled
across those two reads, but there are no shortage of things that can delay
interrupts-disabled regions of code ranging from SMI handlers to vCPU
preemption.  It would be good to have some indication as to why the clock
was marked unstable.

Therefore, re-read the watchdog clock on either side of the read from the
clock under test.  If the watchdog clock shows an excessive time delta
between its pair of reads, the reads are retried.

The maximum number of retries is specified by a new kernel boot parameter
clocksource.max_cswd_read_retries, which defaults to three, that is, up to
four reads, one initial and up to three retries.  If more than one retry
was required, a message is printed on the console (the occasional single
retry is expected behavior, especially in guest OSes).  If the maximum
number of retries is exceeded, the clock under test will be marked
unstable.  However, the probability of this happening due to various sorts
of delays is quite small.  In addition, the reason (clock-read delays) for
the unstable marking will be apparent.

Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Feng Tang <feng.tang@intel.com>
Link: https://lore.kernel.org/r/20210527190124.440372-1-paulmck@kernel.org
2021-06-22 16:53:16 +02:00
Bart Van Assche
556910e392 block: Introduce the ioprio rq-qos policy
Introduce an rq-qos policy that assigns an I/O priority to requests based
on blk-cgroup configuration settings. This policy has the following
advantages over the ioprio_set() system call:
- This policy is cgroup based so it has all the advantages of cgroups.
- While ioprio_set() does not affect page cache writeback I/O, this rq-qos
  controller affects page cache writeback I/O for filesystems that support
  assiociating a cgroup with writeback I/O. See also
  Documentation/admin-guide/cgroup-v2.rst.

Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20210618004456.7280-5-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-21 15:03:40 -06:00
Rafael J. Wysocki
6cbab787c8 Merge back cpufreq material for v5.14. 2021-06-21 18:32:42 +02:00
Mauro Carvalho Chehab
2793e19d63 docs: admin-guide: sysctl: avoid using ReST :doc:foo markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/12abd2290c7ebc05c89178d2556bea740bd70fac.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:36 -06:00
Mauro Carvalho Chehab
e499f4c297 docs: admin-guide: hw-vuln: avoid using ReST :doc:foo markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/4e378517761f3df07165d5ecdac5a0a81577e68f.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:36 -06:00
Mauro Carvalho Chehab
17420f3138 docs: admin-guide: pm: avoid using ReST :doc:foo markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/04616d9fc0b4a0d33486fa0018631a2db2eba860.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:36 -06:00
Mauro Carvalho Chehab
349660e944 docs: admin-guide: reporting-issues.rst: replace some characters
The conversion tools used during DocBook/LaTeX/html/Markdown->ReST
conversion and some cut-and-pasted text contain some characters that
aren't easily reachable on standard keyboards and/or could cause
troubles when parsed by the documentation build system.

Replace the occurences of the following characters:

	- U+00a0 (' '): NO-BREAK SPACE
	  as it can cause lines being truncated on PDF output

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/551a2af0e654226067e5c376d3e2d959cc738f39.1623826294.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:22:33 -06:00
Andy Shevchenko
d3121e64ad ACPI: sysfs: Allow bitmap list to be supplied to acpi_mask_gpe
Currently we need to use as many acpi_mask_gpe options as we want to have
GPEs to be masked. Even with two it already becomes inconveniently large
the kernel command line.

Instead, allow acpi_mask_gpe to represent bitmap list.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-17 17:10:11 +02:00
Robin Murphy
531353e650 iommu: Update "iommu.strict" documentation
Consolidating the flush queue logic also meant that the "iommu.strict"
option started taking effect on x86 as well. Make sure we document that.

Fixes: a250c23f15 ("iommu: remove DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/2c8c06e1b449d6b060c5bf9ad3b403cd142f405d.1623682646.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-06-17 17:03:46 +02:00
Steven Rostedt (VMware)
f38601368f tracing: Add tp_printk_stop_on_boot option
Add a kernel command line option that disables printing of events to
console at late_initcall_sync(). This is useful when needing to see
specific events written to console on boot up, but not wanting it when
user space starts, as user space may make the console so noisy that the
system becomes inoperable.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-17 11:01:15 -04:00
Kir Kolyshkin
828615950b docs/cgroup-v1/blkio: update for 5.x kernels
Commit bf382fb0bcef4 ("block: remove legacy IO schedulers", Oct 12 2018)
removes the CFQ scheduler, together with blkio.weight and
blkio.weight_device described in cgroup v1 documentation. Users are
supposed to use the BFQ scheduler, which cgroup file for setting weight
is blkio.bfq.weight, but there is no way to set per-device weight.

Later, commit 795fe54c2a per-device weights for BFQ, meaning that
blkio.bfq.weight and blkio.bfq.weight_device can be used in a way
similar to the old CFQ cgroup interface.

Yet, the cgroup v1 docs were never updated. Fix this:
 - use the new file names;
 - fix the range for weight (used to be 10..1000, now 1..1000);
 - link to BFQ scheduler docs.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-16 11:32:03 -06:00
Kir Kolyshkin
37fe403898 docs/cgroup-v1/blkio: stop abusing itemized list
Fix many formatting issues by stop (ab)using itemized lists for
everything (mostly replaced by definition lists).

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-16 11:32:02 -06:00
Kees Cook
c811659bb9 pstore/blk: Fix kerndoc and redundancy on blkdev param
Remove redundant details of blkdev and fix up resulting kerndoc.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
2021-06-16 09:27:32 -07:00
Kees Cook
7bb9557b48 pstore/blk: Use the normal block device I/O path
Stop poking into block layer internals and just open the block device
file an use kernel_read and kernel_write on it. Note that this means
the transformation from name_to_dev_t can't be used anymore when
pstore_blk is loaded as a module: a full filesystem device path name
must be used instead. Additionally removes ":internal:" kerndoc link,
since no such documentation remains.

Co-developed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
2021-06-16 09:26:56 -07:00
Mauro Carvalho Chehab
6ef43d273e media: admin-guide: avoid using ReST :doc:foo markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-16 07:26:46 +02:00
Mauro Carvalho Chehab
703ac06a88 media: docs: */media/index.rst: don't use ReST doc:foo
The :doc:`foo` tag is auto-generated via automarkup.py.
    So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-16 07:26:46 +02:00
Tian Tao
05a463ec1b docs: cputopology: move the sysfs ABI description to right place
Documentation/admin-guide/cputopology.rst is the wrong place to describe
sysfs ABI. So move the cputopology ABI things to
Documentation/ABI/stable/sysfs-devices-system-cpu and add a reference to
ABI doc in Documentation/admin-guide/cputopology.rst.

Link: https://lkml.kernel.org/r/20210319041618.14316-1-song.bao.hua@hisilicon.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Link: https://lore.kernel.org/r/20210611052249.25776-1-song.bao.hua@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-14 16:04:31 -06:00
Baoquan He
b1f4c36366 Documentation: kdump: update kdump guide
Some parts of the guide are aged, hence need be updated.

1) The backup area of the 1st 640K on X86_64 has been removed
   by below commits, update the description accordingly.

   commit 7c321eb2b8 ("x86/kdump: Remove the backup region handling")
   commit 6f599d8423 ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified")

2) Sort out the descripiton of "crashkernel syntax" part.

3) And some other minor cleanups.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Link: https://lore.kernel.org/r/20210609083218.GB591017@MiWiFi-R3L-srv
[jc: added blank line to fix added build warning]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-14 08:12:01 -06:00
Kir Kolyshkin
a9edc03f13 docs: fix a cross-ref
Commit acda97acb2 changes dax.txt to dax.rst.
Fix the references accordingly.

Cc: Igor Matheus Andrade Torrente <igormtorrente@gmail.com>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Link: https://lore.kernel.org/r/20210611030044.1982911-4-kolyshkin@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-13 17:02:46 -06:00
Rafael J. Wysocki
154ae8bb3c cpuidle: teo: Use kerneldoc documentation in admin-guide
There are two descriptions of the TEO (Timer Events Oriented) cpuidle
governor in the kernel source tree, one in the C file containing its
code and one in cpuidle.rst which is part of admin-guide.

Instead of trying to keep them both in sync and in order to reduce
text duplication, include the governor description from the C file
directly into cpuidle.rst.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11 18:36:45 +02:00
Masami Hiramatsu
0ff2bb7d42 docs: bootconfig: Update for mixing value and subkeys
Update document for the mixing value and subkeys on a key.

Link: https://lkml.kernel.org/r/162262196510.264090.15044943496205914148.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-10 13:41:26 -04:00
Joel Fernandes (Google)
0159bb020c Documentation: Add usecases, design and interface for core scheduling
Now that core scheduling is merged, update the documentation.

Co-developed-by: Chris Hyser <chris.hyser@oracle.com>
Signed-off-by: Chris Hyser <chris.hyser@oracle.com>
Co-developed-by: Josh Don <joshdon@google.com>
Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210603013136.370918-1-joel@joelfernandes.org
2021-06-10 09:57:09 +02:00
Suren Baghdasaryan
3958e2d0c3 cgroup: make per-cgroup pressure stall tracking configurable
PSI accounts stalls for each cgroup separately and aggregates it at each
level of the hierarchy. This causes additional overhead with psi_avgs_work
being called for each cgroup in the hierarchy. psi_avgs_work has been
highly optimized, however on systems with large number of cgroups the
overhead becomes noticeable.
Systems which use PSI only at the system level could avoid this overhead
if PSI can be configured to skip per-cgroup stall accounting.
Add "cgroup_disable=pressure" kernel command-line option to allow
requesting system-wide only pressure stall accounting. When set, it
keeps system-wide accounting under /proc/pressure/ but skips accounting
for individual cgroups and does not expose PSI nodes in cgroup hierarchy.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-06-08 14:59:02 -04:00
Mike Rapoport
1a6a9044b9 x86/setup: Remove CONFIG_X86_RESERVE_LOW and reservelow= options
The CONFIG_X86_RESERVE_LOW build time and reservelow= command line option
allowed to control the amount of memory under 1M that would be reserved at
boot to avoid using memory that can be potentially clobbered by BIOS.

Since the entire range under 1M is always reserved there is no need for
these options anymore and they can be removed.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210601075354.5149-3-rppt@kernel.org
2021-06-07 11:12:25 +02:00
Joerg Roedel
b1e650db2c iommu/amd: Add amd_iommu=force_enable option
Add this option to enable the IOMMU on platforms like AMD Stoney,
where the kernel usually disables it because it may cause problems in
some scenarios.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20210603130203.29016-1-joro@8bytes.org
2021-06-04 16:31:13 +02:00
Ingo Molnar
a9e906b71f Merge branch 'sched/urgent' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-06-03 19:00:49 +02:00
Mauro Carvalho Chehab
98b9c7890b docs: admin-guide: media: ipu3.rst: replace some characters
The conversion tools used during DocBook/LaTeX/html/Markdown->ReST
conversion and some cut-and-pasted text contain some characters that
aren't easily reachable on standard keyboards and/or could cause
troubles when parsed by the documentation build system.

Replace the occurences of the following characters:

	- U+201c ('“'): LEFT DOUBLE QUOTATION MARK
	- U+201d ('”'): RIGHT DOUBLE QUOTATION MARK

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-02 15:06:12 +02:00
Sakari Ailus
dc794d3d24 media: staging: ipu3-imgu: Move the UAPI header from include under include/uapi
The header defines the user space interface but may be mistaken as
kernel-only header due to its location. Add "uapi" directory under
driver's include directory and move the header there.

Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-02 11:47:16 +02:00
Rajmohan Mani
3fb10ea4ce thunderbolt: Add support for retimer NVM upgrade when there is no link
With help from platform firmware (ACPI) it is possible to power on
retimers even when there is no USB4 link (e.g nothing is connected to
the USB4 ports). This allows us to bring the USB4 sideband up so that we
can access retimers and upgrade their NVM firmware.

If the platform has support for this, we expose two additional
attributes under USB4 ports: offline and rescan. These can be used to
bring the port offline, rescan for the retimers and put the port online
again. The retimer NVM upgrade itself works the same way than with cable
connected.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-01 10:53:31 +03:00
Greg Kroah-Hartman
910cc95373 Merge 5.13-rc4 into tty-next
We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-31 09:44:28 +02:00
Barry Song
544ef682c6 docs: kernel-parameters: mark numa=off is supported by a bundle of architectures
risc-v and arm64 support numa=off by common arch_numa_init()
in drivers/base/arch_numa.c. x86, ppc, mips, sparc support it
by arch-level early_param.
numa=off is widely used in linux distributions. it is better
to document it.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Link: https://lore.kernel.org/r/20210524051715.13604-1-song.bao.hua@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-27 10:11:39 -06:00
Linus Torvalds
d7c5303fbc Merge tag 'net-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.13-rc4, including fixes from bpf, netfilter,
  can and wireless trees. Notably including fixes for the recently
  announced "FragAttacks" WiFi vulnerabilities. Rather large batch,
  touching some core parts of the stack, too, but nothing hair-raising.

  Current release - regressions:

   - tipc: make node link identity publish thread safe

   - dsa: felix: re-enable TAS guard band mode

   - stmmac: correct clocks enabled in stmmac_vlan_rx_kill_vid()

   - stmmac: fix system hang if change mac address after interface
     ifdown

  Current release - new code bugs:

   - mptcp: avoid OOB access in setsockopt()

   - bpf: Fix nested bpf_bprintf_prepare with more per-cpu buffers

   - ethtool: stats: fix a copy-paste error - init correct array size

  Previous releases - regressions:

   - sched: fix packet stuck problem for lockless qdisc

   - net: really orphan skbs tied to closing sk

   - mlx4: fix EEPROM dump support

   - bpf: fix alu32 const subreg bound tracking on bitwise operations

   - bpf: fix mask direction swap upon off reg sign change

   - bpf, offload: reorder offload callback 'prepare' in verifier

   - stmmac: Fix MAC WoL not working if PHY does not support WoL

   - packetmmap: fix only tx timestamp on request

   - tipc: skb_linearize the head skb when reassembling msgs

  Previous releases - always broken:

   - mac80211: address recent "FragAttacks" vulnerabilities

   - mac80211: do not accept/forward invalid EAPOL frames

   - mptcp: avoid potential error message floods

   - bpf, ringbuf: deny reserve of buffers larger than ringbuf to
     prevent out of buffer writes

   - bpf: forbid trampoline attach for functions with variable arguments

   - bpf: add deny list of functions to prevent inf recursion of tracing
     programs

   - tls splice: check SPLICE_F_NONBLOCK instead of MSG_DONTWAIT

   - can: isotp: prevent race between isotp_bind() and
     isotp_setsockopt()

   - netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check,
     fallback to non-AVX2 version

  Misc:

   - bpf: add kconfig knob for disabling unpriv bpf by default"

* tag 'net-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (172 commits)
  net: phy: Document phydev::dev_flags bits allocation
  mptcp: validate 'id' when stopping the ADD_ADDR retransmit timer
  mptcp: avoid error message on infinite mapping
  mptcp: drop unconditional pr_warn on bad opt
  mptcp: avoid OOB access in setsockopt()
  nfp: update maintainer and mailing list addresses
  net: mvpp2: add buffer header handling in RX
  bnx2x: Fix missing error code in bnx2x_iov_init_one()
  net: zero-initialize tc skb extension on allocation
  net: hns: Fix kernel-doc
  sctp: fix the proc_handler for sysctl encap_port
  sctp: add the missing setting for asoc encap_port
  bpf, selftests: Adjust few selftest result_unpriv outcomes
  bpf: No need to simulate speculative domain for immediates
  bpf: Fix mask direction swap upon off reg sign change
  bpf: Wrap aux data inside bpf_sanitize_info container
  bpf: Fix BPF_LSM kconfig symbol dependency
  selftests/bpf: Add test for l3 use of bpf_redirect_peer
  bpftool: Add sock_release help info for cgroup attach/prog load command
  net: dsa: microchip: enable phy errata workaround on 9567
  ...
2021-05-26 17:44:49 -10:00
Tejun Heo
c2a1197154 Merge branch 'for-5.13-fixes' into for-5.14 2021-05-24 13:43:56 -04:00
zhangyi (F)
51fd43e280 block_dump: remove comments in docs
Now block_dump feature is gone, remove all comments in docs.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210313030146.2882027-4-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24 06:47:21 -06:00