Merge tag 'loongarch-kvm-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.12

1. Revert qspinlock to test-and-set simple lock o

Merge tag 'loongarch-kvm-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.12

1. Revert qspinlock to test-and-set simple lock on VM.
2. Add Loongson Binary Translation extension support.
3. Add PMU support for guest.
4. Enable paravirt feature control from VMM.
5. Implement function kvm_para_has_feature().

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Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/phy/phy_device.c
2560db6ede1a ("net: phy: Fix missing of_n

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/phy/phy_device.c
2560db6ede1a ("net: phy: Fix missing of_node_put() for leds")
1dce520abd46 ("net: phy: Use for_each_available_child_of_node_scoped()")
https://lore.kernel.org/20240904115823.74333648@canb.auug.org.au

Adjacent changes:

drivers/net/ethernet/xilinx/xilinx_axienet.h
drivers/net/ethernet/xilinx/xilinx_axienet_main.c
858430db28a5 ("net: xilinx: axienet: Fix race in axienet_stop")
76abb5d675c4 ("net: xilinx: axienet: Add statistics support")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Merge tag 'mm-hotfixes-stable-2024-09-03-20-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
"17 hotfixes, 15 of which are cc:stable.

Mostly MM, n

Merge tag 'mm-hotfixes-stable-2024-09-03-20-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
"17 hotfixes, 15 of which are cc:stable.

Mostly MM, no identifiable theme. And a few nilfs2 fixups"

* tag 'mm-hotfixes-stable-2024-09-03-20-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
alloc_tag: fix allocation tag reporting when CONFIG_MODULES=n
mm: vmalloc: optimize vmap_lazy_nr arithmetic when purging each vmap_area
mailmap: update entry for Jan Kuliga
codetag: debug: mark codetags for poisoned page as empty
mm/memcontrol: respect zswap.writeback setting from parent cg too
scripts: fix gfp-translate after ___GFP_*_BITS conversion to an enum
Revert "mm: skip CMA pages when they are not available"
maple_tree: remove rcu_read_lock() from mt_validate()
kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y
mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook
nilfs2: fix state management in error path of log writing function
nilfs2: fix missing cleanup on rollforward recovery error
nilfs2: protect references to superblock parameters exposed in sysfs
userfaultfd: don't BUG_ON() if khugepaged yanks our page table
userfaultfd: fix checks for huge PMDs
mm: vmalloc: ensure vmap_block is initialised before adding to queue
selftests: mm: fix build errors on armhf

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mm/memcontrol: respect zswap.writeback setting from parent cg too

Currently, the behavior of zswap.writeback wrt. the cgroup hierarchy
seems a bit odd. Unlike zswap.max, it doesn't honor the value

mm/memcontrol: respect zswap.writeback setting from parent cg too

Currently, the behavior of zswap.writeback wrt. the cgroup hierarchy
seems a bit odd. Unlike zswap.max, it doesn't honor the value from parent
cgroups. This surfaced when people tried to globally disable zswap
writeback, i.e. reserve physical swap space only for hibernation [1] -
disabling zswap.writeback only for the root cgroup results in subcgroups
with zswap.writeback=1 still performing writeback.

The inconsistency became more noticeable after I introduced the
MemoryZSwapWriteback= systemd unit setting [2] for controlling the knob.
The patch assumed that the kernel would enforce the value of parent
cgroups. It could probably be workarounded from systemd's side, by going
up the slice unit tree and inheriting the value. Yet I think it's more
sensible to make it behave consistently with zswap.max and friends.

[1] https://wiki.archlinux.org/title/Power_management/Suspend_and_hibernate#Disable_zswap_writeback_to_use_the_swap_space_only_for_hibernation
[2] https://github.com/systemd/systemd/pull/31734

Link: https://lkml.kernel.org/r/20240823162506.12117-1-me@yhndnzj.com
Fixes: 501a06fe8e4c ("zswap: memcontrol: implement zswap writeback disabling")
Signed-off-by: Mike Yuan <me@yhndnzj.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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Merge drm/drm-fixes into drm-misc-fixes

Let's start the new drm-misc-fixes cycle by bringing in 6.11-rc1.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

- In the series "mm: Avoid possible overflows in dirty throttlin

Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

- In the series "mm: Avoid possible overflows in dirty throttling" Jan
Kara addresses a couple of issues in the writeback throttling code.
These fixes are also targetted at -stable kernels.

- Ryusuke Konishi's series "nilfs2: fix potential issues related to
reserved inodes" does that. This should actually be in the
mm-nonmm-stable tree, along with the many other nilfs2 patches. My
bad.

- More folio conversions from Kefeng Wang in the series "mm: convert to
folio_alloc_mpol()"

- Kemeng Shi has sent some cleanups to the writeback code in the series
"Add helper functions to remove repeated code and improve readability
of cgroup writeback"

- Kairui Song has made the swap code a little smaller and a little
faster in the series "mm/swap: clean up and optimize swap cache
index".

- In the series "mm/memory: cleanly support zeropage in
vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
Hildenbrand has reworked the rather sketchy handling of the use of
the zeropage in MAP_SHARED mappings. I don't see any runtime effects
here - more a cleanup/understandability/maintainablity thing.

- Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
of higher addresses, for aarch64. The (poorly named) series is
"Restructure va_high_addr_switch".

- The core TLB handling code gets some cleanups and possible slight
optimizations in Bang Li's series "Add update_mmu_tlb_range() to
simplify code".

- Jane Chu has improved the handling of our
fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
the series "Enhance soft hwpoison handling and injection".

- Jeff Johnson has sent a billion patches everywhere to add
MODULE_DESCRIPTION() to everything. Some landed in this pull.

- In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
has simplified migration's use of hardware-offload memory copying.

- Yosry Ahmed performs more folio API conversions in his series "mm:
zswap: trivial folio conversions".

- In the series "large folios swap-in: handle refault cases first",
Chuanhua Han inches us forward in the handling of large pages in the
swap code. This is a cleanup and optimization, working toward the end
objective of full support of large folio swapin/out.

- In the series "mm,swap: cleanup VMA based swap readahead window
calculation", Huang Ying has contributed some cleanups and a possible
fixlet to his VMA based swap readahead code.

- In the series "add mTHP support for anonymous shmem" Baolin Wang has
taught anonymous shmem mappings to use multisize THP. By default this
is a no-op - users must opt in vis sysfs controls. Dramatic
improvements in pagefault latency are realized.

- David Hildenbrand has some cleanups to our remaining use of
page_mapcount() in the series "fs/proc: move page_mapcount() to
fs/proc/internal.h".

- David also has some highmem accounting cleanups in the series
"mm/highmem: don't track highmem pages manually".

- Build-time fixes and cleanups from John Hubbard in the series
"cleanups, fixes, and progress towards avoiding "make headers"".

- Cleanups and consolidation of the core pagemap handling from Barry
Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
and utilize them".

- Lance Yang's series "Reclaim lazyfree THP without splitting" has
reduced the latency of the reclaim of pmd-mapped THPs under fairly
common circumstances. A 10x speedup is seen in a microbenchmark.

It does this by punting to aother CPU but I guess that's a win unless
all CPUs are pegged.

- hugetlb_cgroup cleanups from Xiu Jianfeng in the series
"mm/hugetlb_cgroup: rework on cftypes".

- Miaohe Lin's series "Some cleanups for memory-failure" does just that
thing.

- Someone other than SeongJae has developed a DAMON feature in Honggyu
Kim's series "DAMON based tiered memory management for CXL memory".
This adds DAMON features which may be used to help determine the
efficiency of our placement of CXL/PCIe attached DRAM.

- DAMON user API centralization and simplificatio work in SeongJae
Park's series "mm/damon: introduce DAMON parameters online commit
function".

- In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
David Hildenbrand does some maintenance work on zsmalloc - partially
modernizing its use of pageframe fields.

- Kefeng Wang provides more folio conversions in the series "mm: remove
page_maybe_dma_pinned() and page_mkclean()".

- More cleanup from David Hildenbrand, this time in the series
"mm/memory_hotplug: use PageOffline() instead of PageReserved() for
!ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
pages" and permits the removal of some virtio-mem hacks.

- Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
__folio_add_anon_rmap()" is a cleanup to the anon folio handling in
preparation for mTHP (multisize THP) swapin.

- Kefeng Wang's series "mm: improve clear and copy user folio"
implements more folio conversions, this time in the area of large
folio userspace copying.

- The series "Docs/mm/damon/maintaier-profile: document a mailing tool
and community meetup series" tells people how to get better involved
with other DAMON developers. From SeongJae Park.

- A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
that.

- David Hildenbrand sends along more cleanups, this time against the
migration code. The series is "mm/migrate: move NUMA hinting fault
folio isolation + checks under PTL".

- Jan Kara has found quite a lot of strangenesses and minor errors in
the readahead code. He addresses this in the series "mm: Fix various
readahead quirks".

- SeongJae Park's series "selftests/damon: test DAMOS tried regions and
{min,max}_nr_regions" adds features and addresses errors in DAMON's
self testing code.

- Gavin Shan has found a userspace-triggerable WARN in the pagecache
code. The series "mm/filemap: Limit page cache size to that supported
by xarray" addresses this. The series is marked cc:stable.

- Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
and cleanup" cleans up and slightly optimizes KSM.

- Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
code motion. The series (which also makes the memcg-v1 code
Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
under config option" and "mm: memcg: put cgroup v1-specific memcg
data under CONFIG_MEMCG_V1"

- Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
adds an additional feature to this cgroup-v2 control file.

- The series "Userspace controls soft-offline pages" from Jiaqi Yan
permits userspace to stop the kernel's automatic treatment of
excessive correctable memory errors. In order to permit userspace to
monitor and handle this situation.

- Kefeng Wang's series "mm: migrate: support poison recover from
migrate folio" teaches the kernel to appropriately handle migration
from poisoned source folios rather than simply panicing.

- SeongJae Park's series "Docs/damon: minor fixups and improvements"
does those things.

- In the series "mm/zsmalloc: change back to per-size_class lock"
Chengming Zhou improves zsmalloc's scalability and memory
utilization.

- Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
pinning memfd folios" makes the GUP code use FOLL_PIN rather than
bare refcount increments. So these paes can first be moved aside if
they reside in the movable zone or a CMA block.

- Andrii Nakryiko has added a binary ioctl()-based API to
/proc/pid/maps for much faster reading of vma information. The series
is "query VMAs from /proc/<pid>/maps".

- In the series "mm: introduce per-order mTHP split counters" Lance
Yang improves the kernel's presentation of developer information
related to multisize THP splitting.

- Michael Ellerman has developed the series "Reimplement huge pages
without hugepd on powerpc (8xx, e500, book3s/64)". This permits
userspace to use all available huge page sizes.

- In the series "revert unconditional slab and page allocator fault
injection calls" Vlastimil Babka removes a performance-affecting and
not very useful feature from slab fault injection.

* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
mm/mglru: fix ineffective protection calculation
mm/zswap: fix a white space issue
mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
mm/hugetlb: fix possible recursive locking detected warning
mm/gup: clear the LRU flag of a page before adding to LRU batch
mm/numa_balancing: teach mpol_to_str about the balancing mode
mm: memcg1: convert charge move flags to unsigned long long
alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
lib: reuse page_ext_data() to obtain codetag_ref
lib: add missing newline character in the warning message
mm/mglru: fix overshooting shrinker memory
mm/mglru: fix div-by-zero in vmpressure_calc_level()
mm/kmemleak: replace strncpy() with strscpy()
mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
mm: ignore data-race in __swap_writepage
hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
mm: shmem: rename mTHP shmem counters
mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
mm/migrate: putback split folios when numa hint migration fails
...

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mm: add swappiness= arg to memory.reclaim

Allow proactive reclaimers to submit an additional swappiness=<val>
argument to memory.reclaim. This overrides the global or per-memcg
swappiness setting f

mm: add swappiness= arg to memory.reclaim

Allow proactive reclaimers to submit an additional swappiness=<val>
argument to memory.reclaim. This overrides the global or per-memcg
swappiness setting for that reclaim attempt.

For example:

echo "2M swappiness=0" > /sys/fs/cgroup/memory.reclaim

will perform reclaim on the rootcg with a swappiness setting of 0 (no
swap) regardless of the vm.swappiness sysctl setting.

Userspace proactive reclaimers use the memory.reclaim interface to trigger
reclaim. The memory.reclaim interface does not allow for any way to
effect the balance of file vs anon during proactive reclaim. The only
approach is to adjust the vm.swappiness setting. However, there are a few
reasons we look to control the balance of file vs anon during proactive
reclaim, separately from reactive reclaim:

* Swapout should be limited to manage SSD write endurance. In near-OOM
situations we are fine with lots of swap-out to avoid OOMs. As these
are typically rare events, they have relatively little impact on write
endurance. However, proactive reclaim runs continuously and so its
impact on SSD write endurance is more significant. Therefore it is
desireable to control swap-out for proactive reclaim separately from
reactive reclaim

* Some userspace OOM killers like systemd-oomd[1] support OOM killing on
swap exhaustion. This makes sense if the swap exhaustion is triggered
due to reactive reclaim but less so if it is triggered due to proactive
reclaim (e.g. one could see OOMs when free memory is ample but anon is
just particularly cold). Therefore, it's desireable to have proactive
reclaim reduce or stop swap-out before the threshold at which OOM
killing occurs.

In the case of Meta's Senpai proactive reclaimer, we adjust vm.swappiness
before writes to memory.reclaim[2]. This has been in production for
nearly two years and has addressed our needs to control proactive vs
reactive reclaim behavior but is still not ideal for a number of reasons:

* vm.swappiness is a global setting, adjusting it can race/interfere
with other system administration that wishes to control vm.swappiness.
In our case, we need to disable Senpai before adjusting vm.swappiness.

* vm.swappiness is stateful - so a crash or restart of Senpai can leave
a misconfigured setting. This requires some additional management to
record the "desired" setting and ensure Senpai always adjusts to it.

With this patch, we avoid these downsides of adjusting vm.swappiness
globally.

[1]https://www.freedesktop.org/software/systemd/man/latest/systemd-oomd.service.html
[2]https://github.com/facebookincubator/oomd/blob/main/src/oomd/plugins/Senpai.cpp#L585-L598

Link: https://lkml.kernel.org/r/20240103164841.2800183-3-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Suggested-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yue Zhao <findns94@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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Merge branch 'next' into for-linus

Prepare input updates for 6.11 merge window.

Merge tag 'v6.9' into next

Sync up with the mainline to bring in the new cleanup API.

Merge drm-misc-next-2024-07-04 into drm-misc-next-fixes

Let's start the drm-misc-next-fixes cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge drm/drm-next into drm-intel-next

Sync to v6.10-rc3.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge drm/drm-next into drm-xe-next

Needed to get tracing cleanup and add mmio tracing series.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge remote-tracking branch 'drm-misc/drm-misc-next' into HEAD

Merge drm-misc-next tree into the msm-next tree in order to be able to
use HDMI connector framework for the MSM HDMI driver.

Merge drm/drm-next into drm-misc-next

Let's start the new release cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge drm/drm-next into drm-intel-gt-next

Some display refactoring patches are needed in order to allow conflict-
less merging.

Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>

Merge branch 'tip/x86/cpu'

The Lunarlake patches rely on the new VFM stuff.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>

Merge tag 'cgroup-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

- Added Michal Koutný as a maintainer

- Counters in pids.events were be

Merge tag 'cgroup-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

- Added Michal Koutný as a maintainer

- Counters in pids.events were behaving inconsistently. pids.events
made properly hierarchical and pids.events.local added

- misc.peak and misc.events.local added

- cpuset remote partition creation and cpuset.cpus.exclusive handling
improved

- Code cleanups, non-critical fixes, doc updates

- for-6.10-fixes is merged in to receive two non-critical fixes that
didn't trigger pull

* tag 'cgroup-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (23 commits)
cgroup: Add Michal Koutný as a maintainer
cgroup/misc: Introduce misc.events.local
cgroup/rstat: add force idle show helper
cgroup: Protect css->cgroup write under css_set_lock
cgroup/misc: Introduce misc.peak
cgroup_misc: add kernel-doc comments for enum misc_res_type
cgroup/cpuset: Prevent UAF in proc_cpuset_show()
selftest/cgroup: Update test_cpuset_prs.sh to match changes
cgroup/cpuset: Make cpuset.cpus.exclusive independent of cpuset.cpus
cgroup/cpuset: Delay setting of CS_CPU_EXCLUSIVE until valid partition
selftest/cgroup: Fix test_cpuset_prs.sh problems reported by test robot
cgroup/cpuset: Fix remote root partition creation problem
cgroup: avoid the unnecessary list_add(dying_tasks) in cgroup_exit()
cgroup/cpuset: Optimize isolated partition only generate_sched_domains() calls
cgroup/cpuset: Reduce the lock protecting CS_SCHED_LOAD_BALANCE
kernel/cgroup: cleanup cgroup_base_files when fail to add cgroup_psi_files
selftests: cgroup: Add basic tests for pids controller
selftests: cgroup: Lexicographic order in Makefile
cgroup/pids: Add pids.events.local
cgroup/pids: Make event counters hierarchical
...

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cgroup/misc: Introduce misc.events.local

Currently the event counting provided by misc.events is hierarchical,
it's not practical if user is only concerned with events of a
specified cgroup. Therefo

cgroup/misc: Introduce misc.events.local

Currently the event counting provided by misc.events is hierarchical,
it's not practical if user is only concerned with events of a
specified cgroup. Therefore, introduce misc.events.local collect events
specific to the given cgroup.

This is analogous to memory.events.local and pids.events.local.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/misc: Introduce misc.peak

Introduce misc.peak to record the historical maximum usage of the
resource, as in some scenarios the value of misc.max could be
adjusted based on the peak usage of t

cgroup/misc: Introduce misc.peak

Introduce misc.peak to record the historical maximum usage of the
resource, as in some scenarios the value of misc.max could be
adjusted based on the peak usage of the resource.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/cpuset: Make cpuset.cpus.exclusive independent of cpuset.cpus

The "cpuset.cpus.exclusive.effective" value is currently limited to a
subset of its "cpuset.cpus". This makes the exclusive CPUs

cgroup/cpuset: Make cpuset.cpus.exclusive independent of cpuset.cpus

The "cpuset.cpus.exclusive.effective" value is currently limited to a
subset of its "cpuset.cpus". This makes the exclusive CPUs distribution
hierarchy subsumed within the larger "cpuset.cpus" hierarchy. We have to
decide on what CPUs are used locally and what CPUs can be passed down as
exclusive CPUs down the hierarchy and combine them into "cpuset.cpus".

The advantage of the current scheme is to have only one hierarchy to
worry about. However, it make it harder to use as all the "cpuset.cpus"
values have to be properly set along the way down to the designated remote
partition root. It also makes it more cumbersome to find out what CPUs
can be used locally.

Make creation of remote partition simpler by breaking the
dependency of "cpuset.cpus.exclusive" on "cpuset.cpus" and make
them independent entities. Now we have two separate hierarchies -
one for setting "cpuset.cpus.effective" and the other one for setting
"cpuset.cpus.exclusive.effective". We may not need to set "cpuset.cpus"
when we activate a partition root anymore.

Also update Documentation/admin-guide/cgroup-v2.rst and cpuset.c comment
to document this change.

Suggested-by: Petr Malat <oss@malat.biz>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/cpuset: Delay setting of CS_CPU_EXCLUSIVE until valid partition

The CS_CPU_EXCLUSIVE flag is currently set whenever cpuset.cpus.exclusive
is set to make sure that the exclusivity test will be

cgroup/cpuset: Delay setting of CS_CPU_EXCLUSIVE until valid partition

The CS_CPU_EXCLUSIVE flag is currently set whenever cpuset.cpus.exclusive
is set to make sure that the exclusivity test will be run to ensure its
exclusiveness. At the same time, this flag can be changed whenever the
partition root state is changed. For example, the CS_CPU_EXCLUSIVE flag
will be reset whenever a partition root becomes invalid. This makes
using CS_CPU_EXCLUSIVE to ensure exclusiveness a bit fragile.

The current scheme also makes setting up a cpuset.cpus.exclusive
hierarchy to enable remote partition harder as cpuset.cpus.exclusive
cannot overlap with any cpuset.cpus of sibling cpusets if their
cpuset.cpus.exclusive aren't set.

Solve these issues by deferring the setting of CS_CPU_EXCLUSIVE flag
until the cpuset become a valid partition root while adding new checks
in validate_change() to ensure that cpuset.cpus.exclusive of sibling
cpusets cannot overlap.

An additional check is also added to validate_change() to make sure that
cpuset.cpus of one cpuset cannot be a subset of cpuset.cpus.exclusive
of a sibling cpuset to avoid the problem that none of those CPUs will
be available when these exclusive CPUs are extracted out to a newly
enabled partition root. The Documentation/admin-guide/cgroup-v2.rst
file is updated to document the new constraints.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/pids: Add pids.events.local

Hierarchical counting of events is not practical for watching when a
particular pids.max is being hit. Therefore introduce .local flavor of
events file (akin to me

cgroup/pids: Add pids.events.local

Hierarchical counting of events is not practical for watching when a
particular pids.max is being hit. Therefore introduce .local flavor of
events file (akin to memory controller) that collects only events
relevant to given cgroup.

The file is only added to the default hierarchy.

Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/pids: Make event counters hierarchical

The pids.events file should honor the hierarchy, so make the events
propagate from their origin up to the root on the unified hierarchy. The
legacy beha

cgroup/pids: Make event counters hierarchical

The pids.events file should honor the hierarchy, so make the events
propagate from their origin up to the root on the unified hierarchy. The
legacy behavior remains non-hierarchical.

Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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cgroup/pids: Separate semantics of pids.events related to pids.max

Currently, when pids.max limit is breached in the hierarchy, the event
is counted and reported in the cgroup where the forking task

cgroup/pids: Separate semantics of pids.events related to pids.max

Currently, when pids.max limit is breached in the hierarchy, the event
is counted and reported in the cgroup where the forking task resides.

This decouples the limit and the notification caused by the limit making
it hard to detect when the actual limit was effected.

Redefine the pids.events:max as: the number of times the limit of the
cgroup was hit.

(Implementation differentiates also "forkfail" event but this is
currently not exposed as it would better fit into pids.stat. It also
differs from pids.events:max only when pids.max is configured on
non-leaf cgroups.)

Since it changes semantics of the original "max" event, introduce this
change only in the v2 API of the controller and add a cgroup2 mount
option to revert to the legacy behavior.

Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

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Merge topic branches 'clkdev' and 'fixes' into for-linus