linux-toradex.git/lib/test_vmalloc.c, branch v6.4-rc1

Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-04-28T02:42:02+00:00

Pull MM updates from Andrew Morton:

- Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.

- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
Raghav.

- zsmalloc performance improvements from Sergey Senozhatsky.

- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.

- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page()
- make __filemap_get_folio()'s return value more useful

- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.

- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.

- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).

- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.

- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
rather than exclusive, and has fixed a bunch of errors which were
caused by its unintuitive meaning.

- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.

- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.

- Cleanups to do_fault_around() by Lorenzo Stoakes.

- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.

- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.

- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.

- Lorenzo has also contributed further cleanups of vma_merge().

- Chaitanya Prakash provides some fixes to the mmap selftesting code.

- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.

- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.

- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.

- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.

- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.

- Yosry Ahmed has improved the performance of memcg statistics
flushing.

- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.

- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.

- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.

- Pankaj Raghav has made page_endio() unneeded and has removed it.

- Peter Xu contributed some rationalizations of the userfaultfd
selftests.

- Yosry Ahmed has fixed an issue around memcg's page recalim
accounting.

- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.

- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.

- Peter Xu fixes a few issues with uffd-wp at fork() time.

- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.

* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
shmem: restrict noswap option to initial user namespace
mm/khugepaged: fix conflicting mods to collapse_file()
sparse: remove unnecessary 0 values from rc
mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
maple_tree: fix allocation in mas_sparse_area()
mm: do not increment pgfault stats when page fault handler retries
zsmalloc: allow only one active pool compaction context
selftests/mm: add new selftests for KSM
mm: add new KSM process and sysfs knobs
mm: add new api to enable ksm per process
mm: shrinkers: fix debugfs file permissions
mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
migrate_pages_batch: fix statistics for longterm pin retry
userfaultfd: use helper function range_in_vma()
lib/show_mem.c: use for_each_populated_zone() simplify code
mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
fs/buffer: convert create_page_buffers to folio_create_buffers
fs/buffer: add folio_create_empty_buffers helper
...

lib/test_vmalloc.c: add vm_map_ram()/vm_unmap_ram() test case

2023-04-18T23:29:47+00:00

Add vm_map_ram()/vm_unmap_ram() test case to our stress test-suite.

[akpm@linux-foundation.org: fix whitespace, per Lorenzo]
Link: https://lkml.kernel.org/r/20230330190639.431589-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) 
Reviewed-by: Lorenzo Stoakes 
Reviewed-by: Baoquan He 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Matthew Wilcox (Oracle) 
Cc: Oleksiy Avramchenko 
Signed-off-by: Andrew Morton

lib/test_vmalloc.c: Rename kvfree_rcu() to kvfree_rcu_mightsleep()

2023-04-05T13:48:03+00:00

The kvfree_rcu() macro's single-argument form is deprecated.  Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.

Acked-by: Joel Fernandes (Google) 
Signed-off-by: Uladzislau Rezki (Sony) 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Joel Fernandes (Google)

lib/test_vmalloc.c: add parameter use_huge for fix_size_alloc_test

2023-01-19T01:12:41+00:00

Add a parameter `use_huge' for fix_size_alloc_test(), which can be used to
test allocation vie vmalloc_huge for both functionality and performance.

Link: https://lkml.kernel.org/r/20221212055657.698420-1-panqinglin2020@iscas.ac.cn
Signed-off-by: Qinglin Pan 
Cc: "Uladzislau Rezki (Sony)" 
Signed-off-by: Andrew Morton

treewide: use get_random_u32_inclusive() when possible

2022-11-18T01:18:02+00:00

These cases were done with this Coccinelle:

@@
expression H;
expression L;
@@
- (get_random_u32_below(H) + L)
+ get_random_u32_inclusive(L, H + L - 1)

@@
expression H;
expression L;
expression E;
@@
  get_random_u32_inclusive(L,
  H
- + E
- - E
  )

@@
expression H;
expression L;
expression E;
@@
  get_random_u32_inclusive(L,
  H
- - E
- + E
  )

@@
expression H;
expression L;
expression E;
expression F;
@@
  get_random_u32_inclusive(L,
  H
- - E
  + F
- + E
  )

@@
expression H;
expression L;
expression E;
expression F;
@@
  get_random_u32_inclusive(L,
  H
- + E
  + F
- - E
  )

And then subsequently cleaned up by hand, with several automatic cases
rejected if it didn't make sense contextually.

Reviewed-by: Kees Cook 
Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Jason Gunthorpe  # for infiniband
Signed-off-by: Jason A. Donenfeld

treewide: use get_random_u32_below() instead of deprecated function

2022-11-18T01:15:15+00:00

This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
  (E)

Reviewed-by: Kees Cook 
Reviewed-by: Greg Kroah-Hartman 
Acked-by: Darrick J. Wong  # for xfs
Reviewed-by: SeongJae Park  # for damon
Reviewed-by: Jason Gunthorpe  # for infiniband
Reviewed-by: Russell King (Oracle)  # for arm
Acked-by: Ulf Hansson  # for mmc
Signed-off-by: Jason A. Donenfeld

treewide: use get_random_{u8,u16}() when possible, part 2

2022-10-11T23:42:58+00:00

Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster than
wasting the additional bytes from a 32-bit value. This was done by hand,
identifying all of the places where one of the random integer functions
was used in a non-32-bit context.

Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Kees Cook 
Reviewed-by: Yury Norov 
Acked-by: Jakub Kicinski 
Acked-by: Heiko Carstens  # for s390
Signed-off-by: Jason A. Donenfeld

treewide: use prandom_u32_max() when possible, part 2

2022-10-11T23:42:58+00:00

Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done by hand, covering things that coccinelle could not do on its own.

Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Kees Cook 
Reviewed-by: Yury Norov 
Reviewed-by: Jan Kara  # for ext2, ext4, and sbitmap
Acked-by: Jakub Kicinski 
Signed-off-by: Jason A. Donenfeld

lib/test_vmalloc: switch to prandom_u32()

2022-07-04T01:08:42+00:00

A get_random_bytes() function can cause a high contention if it is called
across CPUs simultaneously.  Because it shares one lock per all CPUs:


   class name     con-bounces  contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg
   &crng->lock:   663145       665886        0.05           8.85         261966.66        0.39            7188152       13731279       0.04           11.89        2181582.30       0.16
   -----------
   &crng->lock    307835       [<00000000acba59cd>] _extract_crng+0x48/0x90
   &crng->lock    358051       [<00000000f0075abc>] _crng_backtrack_protect+0x32/0x90
   -----------
   &crng->lock    234241       [<00000000f0075abc>] _crng_backtrack_protect+0x32/0x90
   &crng->lock    431645       [<00000000acba59cd>] _extract_crng+0x48/0x90


Switch from the get_random_bytes() to prandom_u32() that does not have any
internal contention when a random value is needed for the tests.

The reason is to minimize CPU cycles introduced by the test-suite itself
from the vmalloc performance metrics.

Link: https://lkml.kernel.org/r/20220607093449.3100-6-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) 
Cc: Christoph Hellwig 
Cc: Matthew Wilcox 
Cc: Nicholas Piggin 
Cc: Oleksiy Avramchenko 
Signed-off-by: Andrew Morton

lib/test_vmalloc.c: use swap() to make code cleaner

2021-11-06T20:30:37+00:00

Use swap() in order to make code cleaner.  Issue found by coccinelle.

Link: https://lkml.kernel.org/r/20211028111443.15744-1-deng.changcheng@zte.com.cn
Signed-off-by: Changcheng Deng 
Reported-by: Zeal Robot 
Reviewed-by: Uladzislau Rezki (Sony) 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds