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JP Kobryn
e1479b880c memcg: rename do_flush_stats and add force flag 
Patch series "memcg: tracepoint for flushing stats", v3.

This series adds new capability for understanding frequency and circumstances
behind flushing memcg stats.


This patch (of 2):

Change the name to something more consistent with others in the file and
use double unders to signify it is associated with the
mem_cgroup_flush_stats() API call.  Additionally include a new flag that
call sites use to indicate a forced flush; skipping checks and flushing
unconditionally.  There are no changes in functionality.

Link: https://lkml.kernel.org/r/20241029021106.25587-1-inwardvessel@gmail.com
Link: https://lkml.kernel.org/r/20241029021106.25587-2-inwardvessel@gmail.com
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:46 -08:00
Hugh Dickins
ab6e8e74e4 mm: delete the unused put_pages_list() 
The last user of put_pages_list() converted away from it in 6.10 commit
06c375053c ("iommu/vt-d: add wrapper functions for page allocations"):
delete put_pages_list().

Link: https://lkml.kernel.org/r/d9985d6a-293e-176b-e63d-82fdfd28c139@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:45 -08:00
Lorenzo Stoakes
876320d71f selftests/mm: add self tests for guard page feature 
Utilise the kselftest harmness to implement tests for the guard page
implementation.

We start by implement basic tests asserting that guard pages can be
installed, removed and that touching guard pages result in SIGSEGV.  We
also assert that, in removing guard pages from a range, non-guard pages
remain intact.

We then examine different operations on regions containing guard markers
behave to ensure correct behaviour:

* Operations over multiple VMAs operate as expected.
* Invoking MADV_GUARD_INSTALL / MADV_GUARD_REMOVE via process_madvise() in
  batches works correctly.
* Ensuring that munmap() correctly tears down guard markers.
* Using mprotect() to adjust protection bits does not in any way override
  or cause issues with guard markers.
* Ensuring that splitting and merging VMAs around guard markers causes no
  issue - i.e. that a marker which 'belongs' to one VMA can function just
  as well 'belonging' to another.
* Ensuring that madvise(..., MADV_DONTNEED) and madvise(..., MADV_FREE)
  do not remove guard markers.
* Ensuring that mlock()'ing a range containing guard markers does not
  cause issues.
* Ensuring that mremap() can move a guard range and retain guard markers.
* Ensuring that mremap() can expand a guard range and retain guard
  markers (perhaps moving the range).
* Ensuring that mremap() can shrink a guard range and retain guard markers.
* Ensuring that forking a process correctly retains guard markers.
* Ensuring that forking a VMA with VM_WIPEONFORK set behaves sanely.
* Ensuring that lazyfree simply clears guard markers.
* Ensuring that userfaultfd can co-exist with guard pages.
* Ensuring that madvise(..., MADV_POPULATE_READ) and
  madvise(..., MADV_POPULATE_WRITE) error out when encountering
  guard markers.
* Ensuring that madvise(..., MADV_COLD) and madvise(..., MADV_PAGEOUT) do
  not remove guard markers.

If any test is unable to be run due to lack of permissions, that test is
skipped.

Link: https://lkml.kernel.org/r/c3dcca76b736bac0aeaf1dc085927536a253ac94.1730123433.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabkba@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:45 -08:00
Lorenzo Stoakes
75d60eb30d tools: testing: update tools UAPI header for mman-common.h 
Import the new MADV_GUARD_INSTALL/REMOVE madvise flags.

Link: https://lkml.kernel.org/r/ada462fa73fa1defc114242e446ab625b8290b71.1730123433.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabkba@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:45 -08:00
Lorenzo Stoakes
662df3e5c3 mm: madvise: implement lightweight guard page mechanism 
Implement a new lightweight guard page feature, that is regions of
userland virtual memory that, when accessed, cause a fatal signal to
arise.

Currently users must establish PROT_NONE ranges to achieve this.

However this is very costly memory-wise - we need a VMA for each and every
one of these regions AND they become unmergeable with surrounding VMAs.

In addition repeated mmap() calls require repeated kernel context switches
and contention of the mmap lock to install these ranges, potentially also
having to unmap memory if installed over existing ranges.

The lightweight guard approach eliminates the VMA cost altogether - rather
than establishing a PROT_NONE VMA, it operates at the level of page table
entries - establishing PTE markers such that accesses to them cause a
fault followed by a SIGSGEV signal being raised.

This is achieved through the PTE marker mechanism, which we have already
extended to provide PTE_MARKER_GUARD, which we installed via the generic
page walking logic which we have extended for this purpose.

These guard ranges are established with MADV_GUARD_INSTALL.  If the range
in which they are installed contain any existing mappings, they will be
zapped, i.e.  free the range and unmap memory (thus mimicking the
behaviour of MADV_DONTNEED in this respect).

Any existing guard entries will be left untouched.  There is therefore no
nesting of guarded pages.

Guarded ranges are NOT cleared by MADV_DONTNEED nor MADV_FREE (in both
instances the memory range may be reused at which point a user would
expect guards to still be in place), but they are cleared via
MADV_GUARD_REMOVE, process teardown or unmapping of memory ranges.

The guard property can be removed from ranges via MADV_GUARD_REMOVE.  The
ranges over which this is applied, should they contain non-guard entries,
will be untouched, with only guard entries being cleared.

We permit this operation on anonymous memory only, and only VMAs which are
non-special, non-huge and not mlock()'d (if we permitted this we'd have to
drop locked pages which would be rather counterintuitive).

Racing page faults can cause repeated attempts to install guard pages that
are interrupted, result in a zap, and this process can end up being
repeated.  If this happens more than would be expected in normal
operation, we rescind locks and retry the whole thing, which avoids lock
contention in this scenario.

Link: https://lkml.kernel.org/r/6aafb5821bf209f277dfae0787abb2ef87a37542.1730123433.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:45 -08:00
Lorenzo Stoakes
7c53dfbdb0 mm: add PTE_MARKER_GUARD PTE marker 
Add a new PTE marker that results in any access causing the accessing
process to segfault.

This is preferable to PTE_MARKER_POISONED, which results in the same
handling as hardware poisoned memory, and is thus undesirable for cases
where we simply wish to 'soft' poison a range.

This is in preparation for implementing the ability to specify guard pages
at the page table level, i.e.  ranges that, when accessed, should cause
process termination.

Additionally, rename zap_drop_file_uffd_wp() to zap_drop_markers() - the
function checks the ZAP_FLAG_DROP_MARKER flag so naming it for this single
purpose was simply incorrect.

We then reuse the same logic to determine whether a zap should clear a
guard entry - this should only be performed on teardown and never on
MADV_DONTNEED or MADV_FREE.

We additionally add a WARN_ON_ONCE() in hugetlb logic should a guard
marker be encountered there, as we explicitly do not support this
operation and this should not occur.

Link: https://lkml.kernel.org/r/f47f3d5acca2dcf9bbf655b6d33f3dc713e4a4a0.1730123433.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Vlastimil Babka <vbabkba@suse.cz>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:44 -08:00
Lorenzo Stoakes
5f6170a469 mm: pagewalk: add the ability to install PTEs 
Patch series "implement lightweight guard pages", v4.

Userland library functions such as allocators and threading
implementations often require regions of memory to act as 'guard pages' -
mappings which, when accessed, result in a fatal signal being sent to the
accessing process.

The current means by which these are implemented is via a PROT_NONE mmap()
mapping, which provides the required semantics however incur an overhead
of a VMA for each such region.

With a great many processes and threads, this can rapidly add up and incur
a significant memory penalty.  It also has the added problem of preventing
merges that might otherwise be permitted.

This series takes a different approach - an idea suggested by Vlastimil
Babka (and before him David Hildenbrand and Jann Horn - perhaps more - the
provenance becomes a little tricky to ascertain after this - please
forgive any omissions!) - rather than locating the guard pages at the VMA
layer, instead placing them in page tables mapping the required ranges.

Early testing of the prototype version of this code suggests a 5 times
speed up in memory mapping invocations (in conjunction with use of
process_madvise()) and a 13% reduction in VMAs on an entirely idle android
system and unoptimised code.

We expect with optimisation and a loaded system with a larger number of
guard pages this could significantly increase, but in any case these
numbers are encouraging.

This way, rather than having separate VMAs specifying which parts of a
range are guard pages, instead we have a VMA spanning the entire range of
memory a user is permitted to access and including ranges which are to be
'guarded'.

After mapping this, a user can specify which parts of the range should
result in a fatal signal when accessed.

By restricting the ability to specify guard pages to memory mapped by
existing VMAs, we can rely on the mappings being torn down when the
mappings are ultimately unmapped and everything works simply as if the
memory were not faulted in, from the point of view of the containing VMAs.

This mechanism in effect poisons memory ranges similar to hardware memory
poisoning, only it is an entirely software-controlled form of poisoning.

The mechanism is implemented via madvise() behaviour - MADV_GUARD_INSTALL
which installs page table-level guard page markers - and MADV_GUARD_REMOVE
- which clears them.

Guard markers can be installed across multiple VMAs and any existing
mappings will be cleared, that is zapped, before installing the guard page
markers in the page tables.

There is no concept of 'nested' guard markers, multiple attempts to
install guard markers in a range will, after the first attempt, have no
effect.

Importantly, removing guard markers over a range that contains both guard
markers and ordinary backed memory has no effect on anything but the guard
markers (including leaving huge pages un-split), so a user can safely
remove guard markers over a range of memory leaving the rest intact.

The actual mechanism by which the page table entries are specified makes
use of existing logic - PTE markers, which are used for the userfaultfd
UFFDIO_POISON mechanism.

Unfortunately PTE_MARKER_POISONED is not suited for the guard page
mechanism as it results in VM_FAULT_HWPOISON semantics in the fault
handler, so we add our own specific PTE_MARKER_GUARD and adapt existing
logic to handle it.

We also extend the generic page walk mechanism to allow for installation
of PTEs (carefully restricted to memory management logic only to prevent
unwanted abuse).

We ensure that zapping performed by MADV_DONTNEED and MADV_FREE do not
remove guard markers, nor does forking (except when VM_WIPEONFORK is
specified for a VMA which implies a total removal of memory
characteristics).

It's important to note that the guard page implementation is emphatically
NOT a security feature, so a user can remove the markers if they wish.  We
simply implement it in such a way as to provide the least surprising
behaviour.

An extensive set of self-tests are provided which ensure behaviour is as
expected and additionally self-documents expected behaviour of guard
ranges.


This patch (of 5):

The existing generic pagewalk logic permits the walking of page tables,
invoking callbacks at individual page table levels via user-provided
mm_walk_ops callbacks.

This is useful for traversing existing page table entries, but precludes
the ability to establish new ones.

Existing mechanism for performing a walk which also installs page table
entries if necessary are heavily duplicated throughout the kernel, each
with semantic differences from one another and largely unavailable for use
elsewhere.

Rather than add yet another implementation, we extend the generic pagewalk
logic to enable the installation of page table entries by adding a new
install_pte() callback in mm_walk_ops.  If this is specified, then upon
encountering a missing page table entry, we allocate and install a new one
and continue the traversal.

If a THP huge page is encountered at either the PMD or PUD level we split
it only if there are ops->pte_entry() (or ops->pmd_entry at PUD level),
otherwise if there is only an ops->install_pte(), we avoid the unnecessary
split.

We do not support hugetlb at this stage.

If this function returns an error, or an allocation fails during the
operation, we abort the operation altogether.  It is up to the caller to
deal appropriately with partially populated page table ranges.

If install_pte() is defined, the semantics of pte_entry() change - this
callback is then only invoked if the entry already exists.  This is a
useful property, as it allows a caller to handle existing PTEs while
installing new ones where necessary in the specified range.

If install_pte() is not defined, then there is no functional difference to
this patch, so all existing logic will work precisely as it did before.

As we only permit the installation of PTEs where a mapping does not
already exist there is no need for TLB management, however we do invoke
update_mmu_cache() for architectures which require manual maintenance of
mappings for other CPUs.

We explicitly do not allow the existing page walk API to expose this
feature as it is dangerous and intended for internal mm use only. 
Therefore we provide a new walk_page_range_mm() function exposed only to
mm/internal.h.

We take the opportunity to additionally clean up the page walker logic to
be a little easier to follow.

Link: https://lkml.kernel.org/r/cover.1730123433.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/51b432ebef013e3fdf9f92101533435de1bffadf.1730123433.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Jann Horn <jannh@google.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Vlastimil Babka <vbabkba@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:44 -08:00
Sabyrzhan Tasbolatov
4e4d9c72c9 kasan: delete CONFIG_KASAN_MODULE_TEST 
Since we've migrated all tests to the KUnit framework, we can delete
CONFIG_KASAN_MODULE_TEST and mentioning of it in the documentation as
well.

I've used the online translator to modify the non-English documentation.

[snovitoll@gmail.com: fix indentation in translation]
  Link: https://lkml.kernel.org/r/20241020042813.3223449-1-snovitoll@gmail.com
Link: https://lkml.kernel.org/r/20241016131802.3115788-4-snovitoll@gmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hu Haowen <2023002089@link.tyut.edu.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:44 -08:00
Sabyrzhan Tasbolatov
ca79a00bb9 kasan: migrate copy_user_test to kunit 
Migrate the copy_user_test to the KUnit framework to verify out-of-bound
detection via KASAN reports in copy_from_user(), copy_to_user() and their
static functions.

This is the last migrated test in kasan_test_module.c, therefore delete
the file.

[arnd@arndb.de: export copy_to_kernel_nofault]
  Link: https://lkml.kernel.org/r/20241018151112.3533820-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20241016131802.3115788-3-snovitoll@gmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hu Haowen <2023002089@link.tyut.edu.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Yanteng Si <siyanteng@loongson.cn>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:44 -08:00
Sabyrzhan Tasbolatov
ae193dd793 kasan: move checks to do_strncpy_from_user 
Patch series "kasan: migrate the last module test to kunit", v4.

copy_user_test() is the last KUnit-incompatible test with
CONFIG_KASAN_MODULE_TEST requirement, which we are going to migrate to
KUnit framework and delete the former test and Kconfig as well.

In this patch series:

	- [1/3] move kasan_check_write() and check_object_size() to
		do_strncpy_from_user() to cover with KASAN checks with
		multiple conditions	in strncpy_from_user().

	- [2/3] migrated copy_user_test() to KUnit, where we can also test
		strncpy_from_user() due to [1/4].

		KUnits have been tested on:
		- x86_64 with CONFIG_KASAN_GENERIC. Passed
		- arm64 with CONFIG_KASAN_SW_TAGS. 1 fail. See [1]
		- arm64 with CONFIG_KASAN_HW_TAGS. 1 fail. See [1]
		[1] https://lore.kernel.org/linux-mm/CACzwLxj21h7nCcS2-KA_q7ybe+5pxH0uCDwu64q_9pPsydneWQ@mail.gmail.com/

	- [3/3] delete CONFIG_KASAN_MODULE_TEST and documentation occurrences.


This patch (of 3):

Since in the commit 2865baf54077("x86: support user address masking
instead of non-speculative conditional") do_strncpy_from_user() is called
from multiple places, we should sanitize the kernel *dst memory and size
which were done in strncpy_from_user() previously.

Link: https://lkml.kernel.org/r/20241016131802.3115788-1-snovitoll@gmail.com
Link: https://lkml.kernel.org/r/20241016131802.3115788-2-snovitoll@gmail.com
Fixes: 2865baf540 ("x86: support user address masking instead of non-speculative conditional")
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hu Haowen <2023002089@link.tyut.edu.cn>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:43 -08:00
Barry Song
aaf2914aec mm: add per-order mTHP swpin counters 
This helps profile the sizes of folios being swapped in. Currently,
only mTHP swap-out is being counted.
The new interface can be found at:
/sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats
         swpin
For example,
cat /sys/kernel/mm/transparent_hugepage/hugepages-64kB/stats/swpin
12809
cat /sys/kernel/mm/transparent_hugepage/hugepages-32kB/stats/swpin
4763

[v-songbaohua@oppo.com: add a blank line in doc]
  Link: https://lkml.kernel.org/r/20241030233423.80759-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20241026082423.26298-1-21cnbao@gmail.com
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:43 -08:00
Kanchana P Sridhar
ed882add6d mm: zswap: zswap_store_page() will initialize entry after adding to xarray. 
This incorporates Yosry's suggestions in [1] for further simplifying
zswap_store_page().  If the page is successfully compressed and added to
the xarray, we get the pool/objcg refs, and initialize all the entry's
members.  Only after this, we add it to the zswap LRU.

In the time between the entry's addition to the xarray and it's member
initialization, we are protected against concurrent stores/loads/swapoff
through the folio lock, and are protected against writeback because the
entry is not on the LRU yet.

This way, we don't have to drop the pool/objcg refs, now that the entry
initialization is centralized to the successful page store code path.

zswap_compress() is modified to take a zswap_pool parameter in keeping
with this simplification (as against obtaining this from entry->pool).

[1]: https://lore.kernel.org/all/CAJD7tkZh6ufHQef5HjXf_F5b5LC1EATexgseD=4WvrO+a6Ni6w@mail.gmail.com/

Link: https://lkml.kernel.org/r/20241002173329.213722-1-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:43 -08:00
Kanchana P Sridhar
0c560dd860 mm: swap: count successful large folio zswap stores in hugepage zswpout stats 
Added a new MTHP_STAT_ZSWPOUT entry to the sysfs transparent_hugepage
stats so that successful large folio zswap stores can be accounted under
the per-order sysfs "zswpout" stats:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout

Other non-zswap swap device swap-out events will be counted under
the existing sysfs "swpout" stats:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/swpout

Also, added documentation for the newly added sysfs per-order hugepage
"zswpout" stats. The documentation clarifies that only non-zswap swapouts
will be accounted in the existing "swpout" stats.

Link: https://lkml.kernel.org/r/20241001053222.6944-8-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:43 -08:00
Kanchana P Sridhar
b7c0ccdfba mm: zswap: support large folios in zswap_store() 
This series enables zswap_store() to accept and store large folios.  The
most significant contribution in this series is from the earlier RFC
submitted by Ryan Roberts [1].  Ryan's original RFC has been migrated to
mm-unstable as of 9-30-2024 in patch 6 of this series, and adapted based
on code review comments received for the current patch-series.

[1]: [RFC PATCH v1] mm: zswap: Store large folios without splitting
     https://lore.kernel.org/linux-mm/20231019110543.3284654-1-ryan.roberts@arm.com/T/#u

The first few patches do the prep work for supporting large folios in
zswap_store.  Patch 6 provides the main functionality to swap-out large
folios in zswap.  Patch 7 adds sysfs per-order hugepages "zswpout"
counters that get incremented upon successful zswap_store of large folios,
and also updates the documentation for this:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout

This series is a pre-requisite for zswap compress batching of large folio
swap-out and decompress batching of swap-ins based on swapin_readahead(),
using Intel IAA hardware acceleration, which we would like to submit in
subsequent patch-series, with performance improvement data.

Thanks to Ying Huang for pre-posting review feedback and suggestions!

Thanks also to Nhat, Yosry, Johannes, Barry, Chengming, Usama, Ying and
Matthew for their helpful feedback, code/data reviews and suggestions!

I would like to thank Ryan Roberts for his original RFC [1].


System setup for testing:
=========================

Testing of this series was done with mm-unstable as of 9-27-2024, commit
de2fbaa6d9c3576ec7133ed02a370ec9376bf000 (without this patch-series) and
mm-unstable 9-30-2024 commit c121617e3606be6575cdacfdb63cc8d67b46a568
(with this patch-series).  Data was gathered on an Intel Sapphire Rapids
server, dual-socket 56 cores per socket, 4 IAA devices per socket, 503 GiB
RAM and 525G SSD disk partition swap.  Core frequency was fixed at
2500MHz.

The vm-scalability "usemem" test was run in a cgroup whose memory.high was
fixed at 150G.  The is no swap limit set for the cgroup.  30 usemem
processes were run, each allocating and writing 10G of memory, and
sleeping for 10 sec before exiting:

usemem --init-time -w -O -s 10 -n 30 10g

Other kernel configuration parameters:

    zswap compressors : zstd, deflate-iaa
    zswap allocator   : zsmalloc
    vm.page-cluster   : 2

In the experiments where "deflate-iaa" is used as the zswap compressor,
IAA "compression verification" is enabled by default (cat
/sys/bus/dsa/drivers/crypto/verify_compress).  Hence each IAA compression
will be decompressed internally by the "iaa_crypto" driver, the crc-s
returned by the hardware will be compared and errors reported in case of
mismatches.  Thus "deflate-iaa" helps ensure better data integrity as
compared to the software compressors, and the experimental data listed
below is with verify_compress set to "1".

Metrics reporting methodology:
==============================
Total and average throughput are derived from the individual 30 processes'
throughputs reported by usemem.  elapsed/sys times are measured with perf.

All percentage changes are "new" vs.  "old"; hence a positive value
denotes an increase in the metric, whether it is throughput or latency,
and a negative value denotes a reduction in the metric.  Positive
throughput change percentages and negative latency change percentages
denote improvements.

The vm stats and sysfs hugepages stats included with the performance data
provide details on the swapout activity to zswap/swap device.


Testing labels used in data summaries:
======================================
The data refers to these test configurations and the before/after
comparisons that they do:

 before-case1:
 -------------
 mm-unstable 9-27-2024, CONFIG_THP_SWAP=N (compares zswap 4K vs. zswap 64K)

 In this scenario, CONFIG_THP_SWAP=N results in 64K/2M folios to be split
 into 4K folios that get processed by zswap.

 before-case2:
 -------------
 mm-unstable 9-27-2024, CONFIG_THP_SWAP=Y (compares SSD swap large folios vs. zswap large folios)

 In this scenario, CONFIG_THP_SWAP=Y results in zswap rejecting large
 folios, which will then be stored by the SSD swap device.

 after:
 ------
 v10 of this patch-series, CONFIG_THP_SWAP=Y

 The "after" is CONFIG_THP_SWAP=Y and v10 of this patch-series, that results
 in 64K/2M folios to not be split, and to be processed by zswap_store.


Regression Testing:
===================
I ran vm-scalability usemem without large folios, i.e., only 4K folios with
mm-unstable and this patch-series. The main goal was to make sure that
there is no functional or performance regression wrt the earlier zswap
behavior for 4K folios, now that 4K folios will be processed by the new
zswap_store() code.

The data indicates there is no significant regression.

 -------------------------------------------------------------------------------
 4K folios:
 ==========

 zswap compressor                zstd          zstd        zstd       zstd v10
                         before-case1  before-case2       after      vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    4,793,363     4,880,978   4,853,074       1%     -1%
 Average throughput (KB/s)    159,778       162,699     161,769       1%     -1%
 elapsed time (sec)            130.14        123.17      126.29      -3%      3%
 sys time (sec)              3,135.53      2,985.64    3,083.18      -2%      3%
 memcg_high                   446,826       444,626     452,930        
 memcg_swap_fail                    0             0           0              
 zswpout                   48,932,107    48,931,971  48,931,820             
 zswpin                           383           386         397            
 pswpout                            0             0           0              
 pswpin                             0             0           0              
 thp_swpout                         0             0           0              
 thp_swpout_fallback                0             0           0              
 64kB-mthp_swpout_fallback          0             0           0              
 pgmajfault                     3,063         3,077       3,479          
 swap_ra                           93            94          96             
 swap_ra_hit                       47            47          50             
 ZSWPOUT-64kB                     n/a           n/a           0              
 SWPOUT-64kB                        0             0           0
 -------------------------------------------------------------------------------


Performance Testing:
====================

We list the data for 64K folios with before/after data per-compressor,
followed by the same for 2M pmd-mappable folios.


 -------------------------------------------------------------------------------
 64K folios: zstd:
 =================

 zswap compressor                zstd          zstd         zstd      zstd v10
                         before-case1  before-case2        after     vs.    vs.
                                                                    case1  case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,222,213     1,076,611    6,159,776      18%   472% 
 Average throughput (KB/s)    174,073        35,887      205,325      18%   472%
 elapsed time (sec)            120.50        347.16       108.33     -10%   -69%
 sys time (sec)              2,930.33        248.16     2,549.65     -13%   927%
 memcg_high                   416,773       552,200      465,874                   
 memcg_swap_fail            3,192,906         1,293        1,012                   
 zswpout                   48,931,583        20,903   48,931,218                  
 zswpin                           384           363          410                   
 pswpout                            0    40,778,448            0                   
 pswpin                             0            16            0                   
 thp_swpout                         0             0            0                   
 thp_swpout_fallback                0             0            0                   
 64kB-mthp_swpout_fallback  3,192,906         1,293        1,012                   
 pgmajfault                     3,452         3,072        3,061                   
 swap_ra                           90            87          107                   
 swap_ra_hit                       42            43           57                   
 ZSWPOUT-64kB                     n/a           n/a    3,057,173                   
 SWPOUT-64kB                        0     2,548,653            0                   
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 64K folios: deflate-iaa:
 ========================

 zswap compressor         deflate-iaa   deflate-iaa  deflate-iaa deflate-iaa v10
                         before-case1  before-case2        after     vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,652,608     1,089,180    7,189,778     27%    560% 
 Average throughput (KB/s)    188,420        36,306      239,659     27%    560%
 elapsed time (sec)            102.90        343.35        87.05    -15%    -75%
 sys time (sec)              2,246.86        213.53     1,864.16    -17%    773%
 memcg_high                   576,104       502,907      642,083                    
 memcg_swap_fail            4,016,117         1,407        1,478                    
 zswpout                   61,163,423        22,444   57,798,716                    
 zswpin                           401           368          454                    
 pswpout                            0    40,862,080            0                    
 pswpin                             0            20            0                    
 thp_swpout                         0             0            0                    
 thp_swpout_fallback                0             0            0                    
 64kB-mthp_swpout_fallback  4,016,117         1,407        1,478                    
 pgmajfault                     3,063         3,153        3,122                    
 swap_ra                           96            93          156                    
 swap_ra_hit                       46            45           83                    
 ZSWPOUT-64kB                     n/a           n/a    3,611,032                    
 SWPOUT-64kB                        0     2,553,880            0                  
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 2M folios: zstd:
 ================

 zswap compressor                zstd          zstd         zstd      zstd v10
                         before-case1  before-case2        after     vs.    vs.
                                                                   case1  case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,895,500     1,109,694    6,484,224     10%    484%
 Average throughput (KB/s)    196,516        36,989      216,140     10%    484%
 elapsed time (sec)            108.77        334.28       106.33     -2%    -68%
 sys time (sec)              2,657.14         94.88     2,376.13    -11%   2404%
 memcg_high                    64,200        66,316       56,898                  
 memcg_swap_fail              101,182            70           27                  
 zswpout                   48,931,499        36,507   48,890,640                  
 zswpin                           380           379          377                  
 pswpout                            0    40,166,400            0                  
 pswpin                             0             0            0                  
 thp_swpout                         0        78,450            0                  
 thp_swpout_fallback          101,182            70           27                  
 2MB-mthp_swpout_fallback           0             0           27                  
 pgmajfault                     3,067         3,417        3,311                  
 swap_ra                           91            90          854                  
 swap_ra_hit                       45            45          810                  
 ZSWPOUT-2MB                      n/a           n/a       95,459                  
 SWPOUT-2MB                         0        78,450            0                 
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 2M folios: deflate-iaa:
 =======================

 zswap compressor         deflate-iaa   deflate-iaa  deflate-iaa deflate-iaa v10
                         before-case1  before-case2        after     vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)   6,286,587      1,126,785    7,073,464     13%    528%
 Average throughput (KB/s)   209,552         37,559      235,782     13%    528%
 elapsed time (sec)            96.19         333.03        85.79    -11%    -74%
 sys time (sec)             2,141.44          99.96     1,826.67    -15%   1727%
 memcg_high                   99,253         64,666       79,718                    
 memcg_swap_fail             129,074             53          165                    
 zswpout                  61,312,794         28,321   56,045,120                    
 zswpin                          383            406          403                    
 pswpout                           0     40,048,128            0                    
 pswpin                            0              0            0                    
 thp_swpout                        0         78,219            0                    
 thp_swpout_fallback         129,074             53          165                    
 2MB-mthp_swpout_fallback          0              0          165                    
 pgmajfault                    3,430          3,077       31,468                    
 swap_ra                          91            103       84,373                    
 swap_ra_hit                      47             46       84,317                    
 ZSWPOUT-2MB                     n/a            n/a      109,229                    
 SWPOUT-2MB                        0         78,219            0                
 -------------------------------------------------------------------------------


And finally, this is a comparison of deflate-iaa vs. zstd with v10 of this
patch-series:

 ---------------------------------------------
                  zswap_store large folios v10
                  Impr w/ deflate-iaa vs. zstd

                       64K folios    2M folios
 ---------------------------------------------
 Throughput (KB/s)            17%           9%
 elapsed time (sec)          -20%         -19%
 sys time (sec)              -27%         -23%
 ---------------------------------------------


Conclusions based on the performance results:
=============================================

 v10 wrt before-case1:
 ---------------------
 We see significant improvements in throughput, elapsed and sys time for
 zstd and deflate-iaa, when comparing before-case1 (THP_SWAP=N) vs. after
 (THP_SWAP=Y) with zswap_store large folios.

 v10 wrt before-case2:
 ---------------------
 We see even more significant improvements in throughput and elapsed time
 for zstd and deflate-iaa, when comparing before-case2 (large-folio-SSD)
 vs. after (large-folio-zswap). The sys time increases with
 large-folio-zswap as expected, due to the CPU compression time
 vs. asynchronous disk write times, as pointed out by Ying and Yosry.
 
 In before-case2, when zswap does not store large folios, only allocations
 and cgroup charging due to 4K folio zswap stores count towards the cgroup
 memory limit. However, in the after scenario, with the introduction of
 zswap_store() of large folios, there is an added component of the zswap
 compressed pool usage from large folio stores from potentially all 30
 processes, that gets counted towards the memory limit. As a result, we see
 higher swapout activity in the "after" data.


Summary:
========
The v10 data presented above shows that zswap_store of large folios
demonstrates good throughput/performance improvements compared to
conventional SSD swap of large folios with a sufficiently large 525G SSD
swap device. Hence, it seems reasonable for zswap_store to support large
folios, so that further performance improvements can be implemented.

In the experimental setup used in this patchset, we have enabled IAA
compress verification to ensure additional hardware data integrity CRC
checks not currently done by the software compressors. We see good
throughput/latency improvements with deflate-iaa vs. zstd with zswap_store
of large folios.

Some of the ideas for further reducing latency that have shown promise in
our experiments, are:

1) IAA compress/decompress batching.
2) Distributing compress jobs across all IAA devices on the socket.

The tests run for this patchset are using only 1 IAA device per core, that
avails of 2 compress engines on the device. In our experiments with IAA
batching, we distribute compress jobs from all cores to the 8 compress
engines available per socket. We further compress the pages in each folio
in parallel in the accelerator. As a result, we improve compress latency
and reclaim throughput.

In decompress batching, we use swapin_readahead to generate a prefetch
batch of 4K folios that we decompress in parallel in IAA.

 ------------------------------------------------------------------------------
                          IAA compress/decompress batching
              Further improvements wrt v10 zswap_store Sequential
                          subpage store using "deflate-iaa":
                       
                      "deflate-iaa" Batching  "deflate-iaa-canned" [2] Batching
                          Additional Impr               Additional Impr   
                     64K folios    2M folios     64K folios    2M folios
 ------------------------------------------------------------------------------
 Throughput (KB/s)          19%          43%           26%           55%
 elapsed time (sec)         -5%         -14%          -10%          -21%
 sys time (sec)              4%          -7%           -4%          -18%
 ------------------------------------------------------------------------------


With zswap IAA compress/decompress batching, we are able to demonstrate
significant performance improvements and memory savings in server
scalability experiments in highly contended system scenarios under
significant memory pressure; as compared to software compressors.  We hope
to submit this work in subsequent patch series.  The current patch-series
is a prequisite for these future submissions.


This patch (of 7):

zswap_store() will store large folios by compressing them page by page.

This patch provides a sequential implementation of storing a large folio
in zswap_store() by iterating through each page in the folio to compress
and store it in the zswap zpool.

zswap_store() calls the newly added zswap_store_page() function for each
page in the folio.  zswap_store_page() handles compressing and storing
each page.

We check the global and per-cgroup limits once at the beginning of
zswap_store(), and only check that the limit is not reached yet.  This is
racy and inaccurate, but it should be sufficient for now.  We also obtain
initial references to the relevant objcg and pool to guarantee that
subsequent references can be acquired by zswap_store_page().  A new
function zswap_pool_get() is added to facilitate this.

If these one-time checks pass, we compress the pages of the folio, while
maintaining a running count of compressed bytes for all the folio's pages.
If all pages are successfully compressed and stored, we do the cgroup
zswap charging with the total compressed bytes, and batch update the
zswap_stored_pages atomic/zswpout event stats with folio_nr_pages() once,
before returning from zswap_store().

If an error is encountered during the store of any page in the folio, all
pages in that folio currently stored in zswap will be invalidated.  Thus,
a folio is either entirely stored in zswap, or entirely not stored in
zswap.

The most important value provided by this patch is it enables swapping out
large folios to zswap without splitting them.  Furthermore, it batches
some operations while doing so (cgroup charging, stats updates).

This patch also forms the basis for building compress batching of pages in
a large folio in zswap_store() by compressing up to say, 8 pages of the
folio in parallel in hardware using the Intel In-Memory Analytics
Accelerator (Intel IAA).

This change reuses and adapts the functionality in Ryan Roberts' RFC
patch [1]:

  "[RFC,v1] mm: zswap: Store large folios without splitting"

  [1] https://lore.kernel.org/linux-mm/20231019110543.3284654-1-ryan.roberts@arm.com/T/#u

Link: https://lkml.kernel.org/r/20241001053222.6944-1-kanchana.p.sridhar@intel.com
Link: https://lkml.kernel.org/r/20241001053222.6944-7-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Originally-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:43 -08:00
Kanchana P Sridhar
6e1fa555ec mm: zswap: modify zswap_stored_pages to be atomic_long_t 
For zswap_store() to support large folios, we need to be able to do a
batch update of zswap_stored_pages upon successful store of all pages in
the folio.  For this, we need to add folio_nr_pages(), which returns a
long, to zswap_stored_pages.

Link: https://lkml.kernel.org/r/20241001053222.6944-6-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:42 -08:00
Kanchana P Sridhar
0201c054c2 mm: zswap: rename zswap_pool_get() to zswap_pool_tryget() 
Modify the name of the existing zswap_pool_get() to zswap_pool_tryget() to
be representative of the call it makes to percpu_ref_tryget().  A
subsequent patch will introduce a new zswap_pool_get() that calls
percpu_ref_get().

The intent behind this change is for higher level zswap API such as
zswap_store() to call zswap_pool_tryget() to check upfront if the pool's
refcount is "0" (which means it could be getting destroyed) and to handle
this as an error condition.  zswap_store() would proceed only if
zswap_pool_tryget() returns success, and any additional pool refcounts
that need to be obtained for compressing sub-pages in a large folio could
simply call zswap_pool_get().

Link: https://lkml.kernel.org/r/20241001053222.6944-4-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:42 -08:00
Kanchana P Sridhar
3d0f560a36 mm: zswap: modify zswap_compress() to accept a page instead of a folio 
For zswap_store() to be able to store a large folio by compressing it one
page at a time, zswap_compress() needs to accept a page as input.  This
will allow us to iterate through each page in the folio in zswap_store(),
compress it and store it in the zpool.

Link: https://lkml.kernel.org/r/20241001053222.6944-3-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:42 -08:00
Kanchana P Sridhar
69bad21551 mm: define obj_cgroup_get() if CONFIG_MEMCG is not defined 
Patch series "mm: zswap swap-out of large folios", v10.

This patch series enables zswap_store() to accept and store large folios. 
The most significant contribution in this series is from the earlier RFC
submitted by Ryan Roberts [1].  Ryan's original RFC has been migrated to
mm-unstable as of 9-30-2024 in patch 6 of this series, and adapted based
on code review comments received for the current patch-series.

[1]: [RFC PATCH v1] mm: zswap: Store large folios without splitting
     https://lore.kernel.org/linux-mm/20231019110543.3284654-1-ryan.roberts@arm.com/T/#u

The first few patches do the prep work for supporting large folios in
zswap_store.  Patch 6 provides the main functionality to swap-out large
folios in zswap.  Patch 7 adds sysfs per-order hugepages "zswpout"
counters that get incremented upon successful zswap_store of large folios,
and also updates the documentation for this:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout

This patch series is a prerequisite for zswap compress batching of large
folio swap-out and decompress batching of swap-ins based on
swapin_readahead(), using Intel IAA hardware acceleration, which we would
like to submit in subsequent patch-series, with performance improvement
data.

Thanks to Ying Huang for pre-posting review feedback and suggestions!

Thanks also to Nhat, Yosry, Johannes, Barry, Chengming, Usama, Ying and
Matthew for their helpful feedback, code/data reviews and suggestions!

Co-development signoff request:
===============================
I would like to thank Ryan Roberts for his original RFC [1] and request
his co-developer signoff on patch 6 in this series. Thanks Ryan!


System setup for testing:
=========================
Testing of this patch series was done with mm-unstable as of 9-27-2024,
commit de2fbaa6d9c3576ec7133ed02a370ec9376bf000 (without this patch-series)
and mm-unstable 9-30-2024 commit c121617e3606be6575cdacfdb63cc8d67b46a568
(with this patch-series). Data was gathered on an Intel Sapphire Rapids
server, dual-socket 56 cores per socket, 4 IAA devices per socket, 503 GiB
RAM and 525G SSD disk partition swap. Core frequency was fixed at 2500MHz.

The vm-scalability "usemem" test was run in a cgroup whose memory.high
was fixed at 150G. The is no swap limit set for the cgroup. 30 usemem
processes were run, each allocating and writing 10G of memory, and sleeping
for 10 sec before exiting:

usemem --init-time -w -O -s 10 -n 30 10g

Other kernel configuration parameters:

    zswap compressors : zstd, deflate-iaa
    zswap allocator   : zsmalloc
    vm.page-cluster   : 2

In the experiments where "deflate-iaa" is used as the zswap compressor,
IAA "compression verification" is enabled by default
(cat /sys/bus/dsa/drivers/crypto/verify_compress). Hence each IAA
compression will be decompressed internally by the "iaa_crypto" driver, the
crc-s returned by the hardware will be compared and errors reported in case
of mismatches. Thus "deflate-iaa" helps ensure better data integrity as
compared to the software compressors, and the experimental data listed
below is with verify_compress set to "1".


Metrics reporting methodology:
==============================
Total and average throughput are derived from the individual 30 processes'
throughputs reported by usemem. elapsed/sys times are measured with perf.

All percentage changes are "new" vs. "old"; hence a positive value
denotes an increase in the metric, whether it is throughput or latency,
and a negative value denotes a reduction in the metric. Positive throughput
change percentages and negative latency change percentages denote improvements.

The vm stats and sysfs hugepages stats included with the performance data
provide details on the swapout activity to zswap/swap device.


Testing labels used in data summaries:
======================================
The data refers to these test configurations and the before/after
comparisons that they do:

 before-case1:
 -------------
 mm-unstable 9-27-2024, CONFIG_THP_SWAP=N (compares zswap 4K vs. zswap 64K)

 In this scenario, CONFIG_THP_SWAP=N results in 64K/2M folios to be split
 into 4K folios that get processed by zswap.

 before-case2:
 -------------
 mm-unstable 9-27-2024, CONFIG_THP_SWAP=Y (compares SSD swap large folios vs. zswap large folios)

 In this scenario, CONFIG_THP_SWAP=Y results in zswap rejecting large
 folios, which will then be stored by the SSD swap device.

 after:
 ------
 v10 of this patch-series, CONFIG_THP_SWAP=Y

 The "after" is CONFIG_THP_SWAP=Y and v10 of this patch-series, that results
 in 64K/2M folios to not be split, and to be processed by zswap_store.


Regression Testing:
===================
I ran vm-scalability usemem without large folios, i.e., only 4K folios with
mm-unstable and this patch-series. The main goal was to make sure that
there is no functional or performance regression wrt the earlier zswap
behavior for 4K folios, now that 4K folios will be processed by the new
zswap_store() code.

The data indicates there is no significant regression.

 -------------------------------------------------------------------------------
 4K folios:
 ==========

 zswap compressor                zstd          zstd        zstd       zstd v10
                         before-case1  before-case2       after      vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    4,793,363     4,880,978   4,853,074       1%     -1%
 Average throughput (KB/s)    159,778       162,699     161,769       1%     -1%
 elapsed time (sec)            130.14        123.17      126.29      -3%      3%
 sys time (sec)              3,135.53      2,985.64    3,083.18      -2%      3%
 memcg_high                   446,826       444,626     452,930        
 memcg_swap_fail                    0             0           0              
 zswpout                   48,932,107    48,931,971  48,931,820             
 zswpin                           383           386         397            
 pswpout                            0             0           0              
 pswpin                             0             0           0              
 thp_swpout                         0             0           0              
 thp_swpout_fallback                0             0           0              
 64kB-mthp_swpout_fallback          0             0           0              
 pgmajfault                     3,063         3,077       3,479          
 swap_ra                           93            94          96             
 swap_ra_hit                       47            47          50             
 ZSWPOUT-64kB                     n/a           n/a           0              
 SWPOUT-64kB                        0             0           0
 -------------------------------------------------------------------------------


Performance Testing:
====================

We list the data for 64K folios with before/after data per-compressor,
followed by the same for 2M pmd-mappable folios.


 -------------------------------------------------------------------------------
 64K folios: zstd:
 =================

 zswap compressor                zstd          zstd         zstd      zstd v10
                         before-case1  before-case2        after     vs.    vs.
                                                                    case1  case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,222,213     1,076,611    6,159,776      18%   472% 
 Average throughput (KB/s)    174,073        35,887      205,325      18%   472%
 elapsed time (sec)            120.50        347.16       108.33     -10%   -69%
 sys time (sec)              2,930.33        248.16     2,549.65     -13%   927%
 memcg_high                   416,773       552,200      465,874                   
 memcg_swap_fail            3,192,906         1,293        1,012                   
 zswpout                   48,931,583        20,903   48,931,218                  
 zswpin                           384           363          410                   
 pswpout                            0    40,778,448            0                   
 pswpin                             0            16            0                   
 thp_swpout                         0             0            0                   
 thp_swpout_fallback                0             0            0                   
 64kB-mthp_swpout_fallback  3,192,906         1,293        1,012                   
 pgmajfault                     3,452         3,072        3,061                   
 swap_ra                           90            87          107                   
 swap_ra_hit                       42            43           57                   
 ZSWPOUT-64kB                     n/a           n/a    3,057,173                   
 SWPOUT-64kB                        0     2,548,653            0                   
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 64K folios: deflate-iaa:
 ========================

 zswap compressor         deflate-iaa   deflate-iaa  deflate-iaa deflate-iaa v10
                         before-case1  before-case2        after     vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,652,608     1,089,180    7,189,778     27%    560% 
 Average throughput (KB/s)    188,420        36,306      239,659     27%    560%
 elapsed time (sec)            102.90        343.35        87.05    -15%    -75%
 sys time (sec)              2,246.86        213.53     1,864.16    -17%    773%
 memcg_high                   576,104       502,907      642,083                    
 memcg_swap_fail            4,016,117         1,407        1,478                    
 zswpout                   61,163,423        22,444   57,798,716                    
 zswpin                           401           368          454                    
 pswpout                            0    40,862,080            0                    
 pswpin                             0            20            0                    
 thp_swpout                         0             0            0                    
 thp_swpout_fallback                0             0            0                    
 64kB-mthp_swpout_fallback  4,016,117         1,407        1,478                    
 pgmajfault                     3,063         3,153        3,122                    
 swap_ra                           96            93          156                    
 swap_ra_hit                       46            45           83                    
 ZSWPOUT-64kB                     n/a           n/a    3,611,032                    
 SWPOUT-64kB                        0     2,553,880            0                  
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 2M folios: zstd:
 ================

 zswap compressor                zstd          zstd         zstd      zstd v10
                         before-case1  before-case2        after     vs.    vs.
                                                                   case1  case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)    5,895,500     1,109,694    6,484,224     10%    484%
 Average throughput (KB/s)    196,516        36,989      216,140     10%    484%
 elapsed time (sec)            108.77        334.28       106.33     -2%    -68%
 sys time (sec)              2,657.14         94.88     2,376.13    -11%   2404%
 memcg_high                    64,200        66,316       56,898                  
 memcg_swap_fail              101,182            70           27                  
 zswpout                   48,931,499        36,507   48,890,640                  
 zswpin                           380           379          377                  
 pswpout                            0    40,166,400            0                  
 pswpin                             0             0            0                  
 thp_swpout                         0        78,450            0                  
 thp_swpout_fallback          101,182            70           27                  
 2MB-mthp_swpout_fallback           0             0           27                  
 pgmajfault                     3,067         3,417        3,311                  
 swap_ra                           91            90          854                  
 swap_ra_hit                       45            45          810                  
 ZSWPOUT-2MB                      n/a           n/a       95,459                  
 SWPOUT-2MB                         0        78,450            0                 
 -------------------------------------------------------------------------------


 -------------------------------------------------------------------------------
 2M folios: deflate-iaa:
 =======================

 zswap compressor         deflate-iaa   deflate-iaa  deflate-iaa deflate-iaa v10
                         before-case1  before-case2        after     vs.     vs.
                                                                   case1   case2
 -------------------------------------------------------------------------------
 Total throughput (KB/s)   6,286,587      1,126,785    7,073,464     13%    528%
 Average throughput (KB/s)   209,552         37,559      235,782     13%    528%
 elapsed time (sec)            96.19         333.03        85.79    -11%    -74%
 sys time (sec)             2,141.44          99.96     1,826.67    -15%   1727%
 memcg_high                   99,253         64,666       79,718                    
 memcg_swap_fail             129,074             53          165                    
 zswpout                  61,312,794         28,321   56,045,120                    
 zswpin                          383            406          403                    
 pswpout                           0     40,048,128            0                    
 pswpin                            0              0            0                    
 thp_swpout                        0         78,219            0                    
 thp_swpout_fallback         129,074             53          165                    
 2MB-mthp_swpout_fallback          0              0          165                    
 pgmajfault                    3,430          3,077       31,468                    
 swap_ra                          91            103       84,373                    
 swap_ra_hit                      47             46       84,317                    
 ZSWPOUT-2MB                     n/a            n/a      109,229                    
 SWPOUT-2MB                        0         78,219            0                
 -------------------------------------------------------------------------------


And finally, this is a comparison of deflate-iaa vs. zstd with v10 of this
patch-series:

 ---------------------------------------------
                  zswap_store large folios v10
                  Impr w/ deflate-iaa vs. zstd

                       64K folios    2M folios
 ---------------------------------------------
 Throughput (KB/s)            17%           9%
 elapsed time (sec)          -20%         -19%
 sys time (sec)              -27%         -23%
 ---------------------------------------------


Conclusions based on the performance results:
=============================================

 v10 wrt before-case1:
 ---------------------
 We see significant improvements in throughput, elapsed and sys time for
 zstd and deflate-iaa, when comparing before-case1 (THP_SWAP=N) vs. after
 (THP_SWAP=Y) with zswap_store large folios.

 v10 wrt before-case2:
 ---------------------
 We see even more significant improvements in throughput and elapsed time
 for zstd and deflate-iaa, when comparing before-case2 (large-folio-SSD)
 vs. after (large-folio-zswap). The sys time increases with
 large-folio-zswap as expected, due to the CPU compression time
 vs. asynchronous disk write times, as pointed out by Ying and Yosry.
 
 In before-case2, when zswap does not store large folios, only allocations
 and cgroup charging due to 4K folio zswap stores count towards the cgroup
 memory limit. However, in the after scenario, with the introduction of
 zswap_store() of large folios, there is an added component of the zswap
 compressed pool usage from large folio stores from potentially all 30
 processes, that gets counted towards the memory limit. As a result, we see
 higher swapout activity in the "after" data.


Summary:
========
The v10 data presented above shows that zswap_store of large folios
demonstrates good throughput/performance improvements compared to
conventional SSD swap of large folios with a sufficiently large 525G SSD
swap device. Hence, it seems reasonable for zswap_store to support large
folios, so that further performance improvements can be implemented.

In the experimental setup used in this patchset, we have enabled IAA
compress verification to ensure additional hardware data integrity CRC
checks not currently done by the software compressors. We see good
throughput/latency improvements with deflate-iaa vs. zstd with zswap_store
of large folios.

Some of the ideas for further reducing latency that have shown promise in
our experiments, are:

1) IAA compress/decompress batching.
2) Distributing compress jobs across all IAA devices on the socket.

The tests run for this patchset are using only 1 IAA device per core, that
avails of 2 compress engines on the device. In our experiments with IAA
batching, we distribute compress jobs from all cores to the 8 compress
engines available per socket. We further compress the pages in each folio
in parallel in the accelerator. As a result, we improve compress latency
and reclaim throughput.

In decompress batching, we use swapin_readahead to generate a prefetch
batch of 4K folios that we decompress in parallel in IAA.

 ------------------------------------------------------------------------------
                          IAA compress/decompress batching
              Further improvements wrt v10 zswap_store Sequential
                          subpage store using "deflate-iaa":
                       
                      "deflate-iaa" Batching  "deflate-iaa-canned" [2] Batching
                          Additional Impr               Additional Impr   
                     64K folios    2M folios     64K folios    2M folios
 ------------------------------------------------------------------------------
 Throughput (KB/s)          19%          43%           26%           55%
 elapsed time (sec)         -5%         -14%          -10%          -21%
 sys time (sec)              4%          -7%           -4%          -18%
 ------------------------------------------------------------------------------


With zswap IAA compress/decompress batching, we are able to demonstrate
significant performance improvements and memory savings in server
scalability experiments in highly contended system scenarios under
significant memory pressure; as compared to software compressors. We hope
to submit this work in subsequent patch series. The current patch-series is
a prequisite for these future submissions.

[1] https://lore.kernel.org/linux-mm/20231019110543.3284654-1-ryan.roberts@arm.com/T/#u
[2] https://patchwork.kernel.org/project/linux-crypto/cover/cover.1710969449.git.andre.glover@linux.intel.com/


This patch (of 6):

This resolves an issue with obj_cgroup_get() not being defined if
CONFIG_MEMCG is not defined.

Before this patch, we would see build errors if obj_cgroup_get() is called
from code that is agnostic of CONFIG_MEMCG.

The zswap_store() changes for large folios in subsequent commits will
require the use of obj_cgroup_get() in zswap code that falls into this
category.

Link: https://lkml.kernel.org/r/20241001053222.6944-1-kanchana.p.sridhar@intel.com
Link: https://lkml.kernel.org/r/20241001053222.6944-2-kanchana.p.sridhar@intel.com
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:26:42 -08:00
Thomas Zimmermann
14062c267f Merge drm/drm-fixes into drm-misc-fixes 
Backmerging to get fixes from v6.12-rc7.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
 2024-11-11 09:23:27 +01:00
Andrew Morton
2ec0859039 Merge branch 'mm-hotfixes-stable' into mm-stable 
Pick up e7ac4daeed ("mm: count zeromap read and set for swapout and
swapin") in order to move

mm: define obj_cgroup_get() if CONFIG_MEMCG is not defined
mm: zswap: modify zswap_compress() to accept a page instead of a folio
mm: zswap: rename zswap_pool_get() to zswap_pool_tryget()
mm: zswap: modify zswap_stored_pages to be atomic_long_t
mm: zswap: support large folios in zswap_store()
mm: swap: count successful large folio zswap stores in hugepage zswpout stats
mm: zswap: zswap_store_page() will initialize entry after adding to xarray.
mm: add per-order mTHP swpin counters

from mm-unstable into mm-stable.
 2024-11-11 00:04:10 -08:00
Barry Song
e7ac4daeed mm: count zeromap read and set for swapout and swapin 
When the proportion of folios from the zeromap is small, missing their
accounting may not significantly impact profiling.  However, it's easy to
construct a scenario where this becomes an issue—for example, allocating
1 GB of memory, writing zeros from userspace, followed by MADV_PAGEOUT,
and then swapping it back in.  In this case, the swap-out and swap-in
counts seem to vanish into a black hole, potentially causing semantic
ambiguity.

On the other hand, Usama reported that zero-filled pages can exceed 10% in
workloads utilizing zswap, while Hailong noted that some app in Android
have more than 6% zero-filled pages.  Before commit 0ca0c24e32 ("mm:
store zero pages to be swapped out in a bitmap"), both zswap and zRAM
implemented similar optimizations, leading to these optimized-out pages
being counted in either zswap or zRAM counters (with pswpin/pswpout also
increasing for zRAM).  With zeromap functioning prior to both zswap and
zRAM, userspace will no longer detect these swap-out and swap-in actions.

We have three ways to address this:

1. Introduce a dedicated counter specifically for the zeromap.

2. Use pswpin/pswpout accounting, treating the zero map as a standard
   backend.  This approach aligns with zRAM's current handling of
   same-page fills at the device level.  However, it would mean losing the
   optimized-out page counters previously available in zRAM and would not
   align with systems using zswap.  Additionally, as noted by Nhat Pham,
   pswpin/pswpout counters apply only to I/O done directly to the backend
   device.

3. Count zeromap pages under zswap, aligning with system behavior when
   zswap is enabled.  However, this would not be consistent with zRAM, nor
   would it align with systems lacking both zswap and zRAM.

Given the complications with options 2 and 3, this patch selects
option 1.

We can find these counters from /proc/vmstat (counters for the whole
system) and memcg's memory.stat (counters for the interested memcg).

For example:

$ grep -E 'swpin_zero|swpout_zero' /proc/vmstat
swpin_zero 1648
swpout_zero 33536

$ grep -E 'swpin_zero|swpout_zero' /sys/fs/cgroup/system.slice/memory.stat
swpin_zero 3905
swpout_zero 3985

This patch does not address any specific zeromap bug, but the missing
swpout and swpin counts for zero-filled pages can be highly confusing and
may mislead user-space agents that rely on changes in these counters as
indicators.  Therefore, we add a Fixes tag to encourage the inclusion of
this counter in any kernel versions with zeromap.

Many thanks to Kanchana for the contribution of changing
count_objcg_event() to count_objcg_events() to support large folios[1],
which has now been incorporated into this patch.

[1] https://lkml.kernel.org/r/20241001053222.6944-5-kanchana.p.sridhar@intel.com

Link: https://lkml.kernel.org/r/20241107011246.59137-1-21cnbao@gmail.com
Fixes: 0ca0c24e32 ("mm: store zero pages to be swapped out in a bitmap")
Co-developed-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Hailong Liu <hailong.liu@oppo.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2024-11-11 00:00:37 -08:00
Shuosheng Huang
078d2f2256 cpufreq: sun50i: add a100 cpufreq support 
Let's add cpufreq nvmem based for allwinner a100 soc. It's similar to h6,
let us use efuse_xlate to extract the differentiated part.

Signed-off-by: Shuosheng Huang <huangshuosheng@allwinnertech.com>
[masterr3c0rd@epochal.quest: add A100 to opp_match_list]
Signed-off-by: Cody Eksal <masterr3c0rd@epochal.quest>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Parthiban Nallathambi <parthiban@linumiz.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 11:24:42 +05:30
Kent Overstreet
2642084f26 bcachefs: Allow for unknown key types in backpointers fsck 
We can't assume that btrees only contain keys of a given type - even if
they only have a single key type listed in the allowed key types for
that btree; this is a forwards compatibility issue.

Reported-by: syzbot+a27c3aaa3640dd3e1dfb@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
 2024-11-11 00:37:19 -05:00
Kent Overstreet
0b6ec0c5ac bcachefs: Fix assertion pop in topology repair 
Fixes: baefd3f849 ("bcachefs: btree_cache.freeable list fixes")
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
 2024-11-11 00:37:18 -05:00
Jinjie Ruan
172bf5ed04 cpufreq: mediatek-hw: Fix wrong return value in mtk_cpufreq_get_cpu_power() 
mtk_cpufreq_get_cpu_power() return 0 if the policy is NULL. Then in
em_create_perf_table(), the later zero check for power is not invalid
as power is uninitialized. As Lukasz suggested, it must return -EINVAL when
the 'policy' is not found. So return -EINVAL to fix it.

Cc: stable@vger.kernel.org
Fixes: 4855e26bcf ("cpufreq: mediatek-hw: Add support for CPUFREQ HW")
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Suggested-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 09:45:17 +05:30
Jinjie Ruan
b51eb0874d cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_power() 
cppc_get_cpu_power() return 0 if the policy is NULL. Then in
em_create_perf_table(), the later zero check for power is not valid
as power is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of active_power() first, so if the callback
failed it should tell the core. So return -EINVAL to fix it.

Fixes: a78e720756 ("cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 09:45:16 +05:30
Jinjie Ruan
be392aa80f cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_cost() 
cppc_get_cpu_cost() return 0 if the policy is NULL. Then in
em_compute_costs(), the later zero check for cost is not valid
as cost is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of get_cost() first, so if the callback
failed it should tell the core. Return -EINVAL to fix it.

Fixes: 1a1374bb8c ("cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/c4765377-7830-44c2-84fa-706b6e304e10@stanley.mountain/
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 09:45:16 +05:30
Andy Shevchenko
db01e46689 cpufreq: loongson3: Check for error code from devm_mutex_init() call 
Even if it's not critical, the avoidance of checking the error code
from devm_mutex_init() call today diminishes the point of using devm
variant of it. Tomorrow it may even leak something. Add the missed
check.

Fixes: ccf5145414 ("cpufreq: Add Loongson-3 CPUFreq driver support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 09:40:03 +05:30
Sibi Sankar
8c776a54d9 cpufreq: scmi: Fix cleanup path when boost enablement fails 
Include free_cpufreq_table in the cleanup path when boost enablement fails.

cc: stable@vger.kernel.org
Fixes: a8e949d41c ("cpufreq: scmi: Enable boost support")
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
 2024-11-11 09:18:25 +05:30
Uwe Kleine-König
dbbd975cc6 fpga: Switch back to struct platform_driver::remove() 
After commit 0edb555a65 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
platform drivers.

Convert all platform drivers below drivers/fpga to use .remove(), with
the eventual goal to drop struct platform_driver::remove_new(). As
.remove() and .remove_new() have the same prototypes, conversion is done
by just changing the structure member name in the driver initializer.

A few white space changes are included to make indention consistent.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20241108160002.252517-2-u.kleine-koenig@baylibre.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
 2024-11-11 10:43:21 +08:00
Dave Airlie
56b70bf9ec Merge tag 'drm-misc-next-2024-11-08' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-next 
drm-misc-next for v6.13:

UAPI Changes:
- Add 1X7X5 media-bus formats.

Cross-subsystem Changes:
- Maintainer updates for VKMS and IT6263.
- Add media-bus-fmt for MEDIA_BUS_FMT_RGB101010_1X7X5_*.
- Add IT6263 DT bindings and driver.

Core Changes:
- Add ABGR210101010 support to panic handler.
- Use ATOMIC64_INIT in drm_file.c
- Improve scheduler teardown documentation.

Driver Changes:
- Make mediatek compile on ARM again.
- Add missing drm/drm_bridge.h header include, already in drm-next.
- Small fixes and cleanups to vkms, bridge/it6505, panfrost, panthor.
- Add panic support to nouveau for nv50+.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/344afe41-d27b-408a-8542-bfecfd3555f6@linux.intel.com
 2024-11-11 12:10:49 +10:00
Esben Haabendal
5a36826a59 rtc: isl12022: Replace uint8_t types with u8 
Keep coding style consistent, by using kernel integer types instead of
standard types.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Link: https://lore.kernel.org/r/20240913-rtc-isl12022-alarm-irq-v2-3-37309d939723@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
 2024-11-11 00:06:46 +01:00
Esben Haabendal
c62d658e52 rtc: isl12022: Add alarm support 
The ISL12022 RTC has a combined INT/fOUT pin, which can be used for alarm
interrupt when frequency output is not enabled.

The device-tree bindings should ensure that interrupt and clock output is
not enabled at the same time.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Link: https://lore.kernel.org/r/20240913-rtc-isl12022-alarm-irq-v2-2-37309d939723@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
 2024-11-11 00:06:46 +01:00
Esben Haabendal
d4a6161f24 rtc: isl12022: Prepare for extending rtc device drvdata 
Add a struct to hold the regmap pointer, so more information can be added.

This is morally a revert of commit f525b210e9 ("rtc: isl12022: Get rid of
unneeded private struct isl12022").

Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Esben Haabendal <esben@geanix.com>
Link: https://lore.kernel.org/r/20240913-rtc-isl12022-alarm-irq-v2-1-37309d939723@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
 2024-11-11 00:06:46 +01:00
Gary Guo
d072acda48 rust: use custom FFI integer types 
Currently FFI integer types are defined in libcore. This commit creates
the `ffi` crate and asks bindgen to use that crate for FFI integer types
instead of `core::ffi`.

This commit is preparatory and no type changes are made in this commit
yet.

Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net
[ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of
  `rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate
  docs slightly and formatted. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
 2024-11-10 23:58:00 +01:00
Gary Guo
2fd6f55c04 rust: map __kernel_size_t and friends also to usize/isize 
Currently bindgen has special logic to recognise `size_t` and `ssize_t`
and map them to Rust `usize` and `isize`. Similarly, `ptrdiff_t` is
mapped to `isize`.

However this falls short for `__kernel_size_t`, `__kernel_ssize_t` and
`__kernel_ptrdiff_t`. To ensure that they are mapped to usize/isize
rather than 32/64 integers depending on platform, blocklist them in
bindgen parameters and manually provide their definition.

Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/r/20240913213041.395655-3-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
 2024-11-10 23:58:00 +01:00
Antonio Quartulli
63a24cf8cc m68k: coldfire/device.c: only build FEC when HW macros are defined 
When CONFIG_FEC is set (due to COMPILE_TEST) along with
CONFIG_M54xx, coldfire/device.c has compile errors due to
missing MCFEC_* and MCF_IRQ_FEC_* symbols.

Make the whole FEC blocks dependent on having the HW macros
defined, rather than on CONFIG_FEC itself.

This fix is very similar to commit e6e1e7b19f ("m68k: coldfire/device.c: only build for MCF_EDMA when h/w macros are defined")

Fixes: b7ce7f0d0e ("m68knommu: merge common ColdFire FEC platform setup code")
To: Greg Ungerer <gerg@linux-m68k.org>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Antonio Quartulli <antonio@mandelbit.com>
Signed-off-by: Greg Ungerer <gerg@kernel.org>
 2024-11-11 08:57:01 +10:00
Jean-Michel Hautbois
f212140962 m68k: mcfgpio: Fix incorrect register offset for CONFIG_M5441x 
Fix a typo in the CONFIG_M5441x preprocessor condition, where the GPIO
register offset was incorrectly set to 8 instead of 0. This prevented
proper GPIO configuration for m5441x targets.

Fixes: bea8bcb12d ("m68knommu: Add support for the Coldfire m5441x.")
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
Signed-off-by: Greg Ungerer <gerg@kernel.org>
 2024-11-11 08:57:01 +10:00
Gary Guo
75c1fd41a6 rust: fix size_t in bindgen prototypes of C builtins 
Without `-fno-builtin`, for functions like memcpy/memmove (and many
others), bindgen seems to be using the clang-provided prototype. This
prototype is ABI-wise compatible, but the issue is that it does not have
the same information as the source code w.r.t. typedefs.

For example, bindgen generates the following:

    extern "C" {
        pub fn strlen(s: *const core::ffi::c_char) -> core::ffi::c_ulong;
    }

note that the return type is `c_ulong` (i.e. unsigned long), despite the
size_t-is-usize behavior (this is default, and we have not opted out
from it using --no-size_t-is-usize).

Similarly, memchr's size argument should be of type `__kernel_size_t`,
but bindgen generates `c_ulong` directly.

We want to ensure any `size_t` is translated to Rust `usize` so that we
can avoid having them be different type on 32-bit and 64-bit
architectures, and hence would require a lot of excessive type casts
when calling FFI functions.

I found that this bindgen behavior (which probably is caused by
libclang) can be disabled by `-fno-builtin`. Using the flag for compiled
code can result in less optimisation because compiler cannot assume
about their properties anymore, but this should not affect bindgen.

[ Trevor asked: "I wonder how reliable this behavior is. Maybe bindgen
  could do a better job controlling this, is there an open issue?".

  Gary replied: ..."apparently this is indeed the suggested approach in
  https://github.com/rust-lang/rust-bindgen/issues/1770". - Miguel ]

Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-2-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
 2024-11-10 23:54:43 +01:00
Jerome Brunet
544177f20b hwmon: (pmbus) add documentation for existing flags 
PMBUS_NO_WRITE_PROTECT and PMBUS_USE_COEFFICIENTS_CMD flags have been added
to pmbus, but the corresponding documentation was not updated.

Update the documentation before adding new flags

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Message-ID: <20241105-tps25990-v4-1-0e312ac70b62@baylibre.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Wenliang Yan
52172ad87a hwmon: (ina226) Add support for SY24655 
SY24655: Support for current and voltage detection as well as
power calculation.

Signed-off-by: Wenliang Yan <wenliang202407@163.com>
Message-ID: <20241106150547.2538-1-wenliang202407@163.com>
[groeck: Changed order of compatible entries;
 dropped spurious extra return statement in is_visible();
 fixed code problems]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Wenliang Yan
0196d07f0e dt-bindings: Add SY24655 to ina2xx devicetree bindings 
SY24655 is similar to INA226. Its supply voltage and pin definitions
are therefore the same. Compared to INA226, SY24655 has two additional
registers for configuring and calculating average power.

Signed-off-by: Wenliang Yan <wenliang202407@163.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Message-ID: <20241106150547.2538-2-wenliang202407@163.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Mariel Tinaco
9c1716bc51 hwmon: (pmbus/ltc2978) add support for ltc7841 
Add support for LTC7841. The LTC7841 is a high performance
PolyPhase® single output synchronous boost converter controller.
Multiphase operation reduces input and output capacitor
requirements and allows the use of smaller inductors than the
single-phase equivalent.

The relevant registers in the LTC7841 are similar to the
LTC7880, only reduced by some amount. So it's just a matter of adding
the chip id. The device also doesn't support polling, on top of the
reduced register set, so a separate case for setting the chip info is
added.

Signed-off-by: Mariel Tinaco <Mariel.Tinaco@analog.com>
Message-ID: <20241029013734.293024-4-Mariel.Tinaco@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Mariel Tinaco
baf88c49a2 hwmon: (pmbus/ltc7841) add support for LTC7841 - docs 
Add LTC7841 to compatible devices of LTC2978

Signed-off-by: Mariel Tinaco <Mariel.Tinaco@analog.com>
Message-ID: <20241029013734.293024-3-Mariel.Tinaco@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Mariel Tinaco
8b882f6ff0 dt-bindings: hwmon: ltc2978: add support for ltc7841 
Add LTC7841 to supported devices of LTC2978. It has similar set of
registers to LTC7880, differing only in number of output channels and
some unimplemented PMBUS status and functionalities.

Signed-off-by: Mariel Tinaco <Mariel.Tinaco@analog.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Message-ID: <20241029013734.293024-2-Mariel.Tinaco@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Ban Feng
46b94c485e hwmon: Add driver for I2C chip Nuvoton NCT7363Y 
The NCT7363Y is a fan controller which provides up to 16
independent FAN input monitors. It can report each FAN input count
values. The NCT7363Y also provides up to 16 independent PWM
outputs. Each PWM can output specific PWM signal by manual mode to
control the FAN duty outside.

Signed-off-by: Ban Feng <kcfeng0@nuvoton.com>
Message-ID: <20241022052905.4062682-3-kcfeng0@nuvoton.com>
[groeck: Dropped unnecessary variable initialization, and , after { }]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Ban Feng
15cae9c0b9 dt-bindings: hwmon: Add NCT7363Y documentation 
Add bindings for the Nuvoton NCT7363Y Fan Controller

Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Ban Feng <kcfeng0@nuvoton.com>
Message-ID: <20241022052905.4062682-2-kcfeng0@nuvoton.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Naresh Solanki
c20a783b67 dt-bindings: hwmon: pmbus: Add bindings for Vicor pli1209bc 
Remove vicor,pli1209bc from trivial-devices as it requires additional
properties and does not fit into the trivial devices category.

Add new bindings for Vicor pli1209bc, a Digital Supervisor with
Isolation for use with BCM Bus Converter Modules.

VR rails are defined under regulator node as expected by pmbus driver.

Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Message-ID: <20241021123044.3648960-1-naresh.solanki@9elements.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Naresh Solanki
c9fb2552fd dt-bindings: hwmon: pmbus: Add bindings for MPS MP297x 
Remove mps297x from trivial-devices as it requires
additional properties and does not fit into the trivial
devices category.

Add new bindings for MPS mp2971, mp2973 & mp2975.
It is Dual-Loop, Digital Multi-Phase Controller with PMBUS
interface

Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Message-ID: <20241022103750.572677-1-naresh.solanki@9elements.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00
Guenter Roeck
547a5c453c MAINTAINERS: Remove Aleksandr Mezin as NZXT-SMART2 driver maintainer 
Per his request, remove Aleksandr Mezin as maintainer of the
NZXT-SMART2 hardware monitoring driver.

Cc: Aleksandr Mezin <mezin.alexander@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
 2024-11-10 14:48:07 -08:00