linux-stable.git/tools/testing/selftests/vm, branch v5.16.2

userfaultfd/selftests: fix hugetlb area allocations

2021-12-31T17:20:12+00:00

Currently, userfaultfd selftest for hugetlb as run from run_vmtests.sh
or any environment where there are 'just enough' hugetlb pages will
always fail with:

  testing events (fork, remap, remove):
		ERROR: UFFDIO_COPY error: -12 (errno=12, line=616)

The ENOMEM error code implies there are not enough hugetlb pages.
However, there are free hugetlb pages but they are all reserved.  There
is a basic problem with the way the test allocates hugetlb pages which
has existed since the test was originally written.

Due to the way 'cleanup' was done between different phases of the test,
this issue was masked until recently.  The issue was uncovered by commit
8ba6e8640844 ("userfaultfd/selftests: reinitialize test context in each
test").

For the hugetlb test, src and dst areas are allocated as PRIVATE
mappings of a hugetlb file.  This means that at mmap time, pages are
reserved for the src and dst areas.  At the start of event testing (and
other tests) the src area is populated which results in allocation of
huge pages to fill the area and consumption of reserves associated with
the area.  Then, a child is forked to fault in the dst area.  Note that
the dst area was allocated in the parent and hence the parent owns the
reserves associated with the mapping.  The child has normal access to
the dst area, but can not use the reserves created/owned by the parent.
Thus, if there are no other huge pages available allocation of a page
for the dst by the child will fail.

Fix by not creating reserves for the dst area.  In this way the child
can use free (non-reserved) pages.

Also, MAP_PRIVATE of a file only makes sense if you are interested in
the contents of the file before making a COW copy.  The test does not do
this.  So, just use MAP_ANONYMOUS | MAP_HUGETLB to create an anonymous
hugetlb mapping.  There is no need to create a hugetlb file in the
non-shared case.

Link: https://lkml.kernel.org/r/20211217172919.7861-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz 
Cc: Axel Rasmussen 
Cc: Peter Xu 
Cc: Andrea Arcangeli 
Cc: Mina Almasry 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

selftests/vm: make MADV_POPULATE_(READ|WRITE) use in-tree headers

2021-11-06T20:30:42+00:00

The madv_populate selftest currently builds with a warning when the
local installed headers (via the distribution) don't include
MADV_POPULATE_READ and MADV_POPULATE_WRITE.  The warning is correct,
because the test cannot locate the necessary header.

The reason is that the in-tree installed headers (usr/include) have a
"linux" instead of a "sys" subdirectory.

Including "linux/mman.h" instead of "sys/mman.h" doesn't work (e.g.,
mmap() and madvise() are not defined that way).  The only thing that
seems to work is including "linux/mman.h" in addition to "sys/mman.h".

We can get rid of our availability check and simplify.

Link: https://lkml.kernel.org/r/20211015165758.41374-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Reported-by: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

selftests: vm: add KSM huge pages merging time test

2021-11-06T20:30:41+00:00

Add test case of KSM merging time using mostly huge pages

Link: https://lkml.kernel.org/r/20211013044045.360251-1-pedrodemargomes@gmail.com
Signed-off-by: Pedro Demarchi Gomes 
Cc: Zhansaya Bagdauletkyzy 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

selftest/vm: fix ksm selftest to run with different NUMA topologies

2021-11-06T20:30:41+00:00

Platforms can have non-contiguous NUMA nodes like below

   #numactl  -H
  available: 2 nodes (0,8)
  .....
  node distances:
  node   0   8
    0:  10  40
    8:  40  10

   #numactl  -H
  available: 1 nodes (1)
  ....
  node distances:
  node   1
    1:  10

Hence update the test to not assume the presence of Node 0 and 1 and
also use numa_num_configured_nodes() instead of numa_max_node for
finding whether to skip the test.

Link: https://lkml.kernel.org/r/20210914141414.350759-1-aneesh.kumar@linux.ibm.com
Fixes: 82e717ad3501 ("selftests: vm: add KSM merging across nodes test")
Signed-off-by: Aneesh Kumar K.V 
Reviewed-by: Pasha Tatashin 
Cc: Zhansaya Bagdauletkyzy 
Cc: Pavel Tatashin 
Cc: Tyler Hicks 
Cc: Hugh Dickins 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

selftests/vm/transhuge-stress: fix ram size thinko

2021-11-06T20:30:41+00:00

When executing transhuge-stress with an argument to specify the virtual
memory size for testing, the ram size is reported as 0, e.g.

  transhuge-stress 384
  thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 0 MiB of ram
  thp-mmap: 0.184 s/loop, 0.957 ms/page,   2090.265 MiB/s  192 succeed,    0 failed

This appears to be due to a thinko in commit 0085d61fe05e
("selftests/vm/transhuge-stress: stress test for memory compaction"),
where, at a guess, the intent was to base "xyz MiB of ram" on `ram`
size.

Here are results after using `ram` size:

  thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 14 MiB of ram

Link: https://lkml.kernel.org/r/20210825135843.29052-1-george_davis@mentor.com
Fixes: 0085d61fe05e ("selftests/vm/transhuge-stress: stress test for memory compaction")
Signed-off-by: George G. Davis 
Cc: Konstantin Khlebnikov 
Cc: Eugeniu Rosca 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

userfaultfd/selftests: fix calculation of expected ioctls

2021-11-06T20:30:39+00:00

Today, we assert that the ioctls the kernel reports as supported for a
registration match a precomputed list.  We decide which ioctls are
supported by examining the memory type.  Then, in several locations we
"fix up" this list by adding or removing things this initial decision
got wrong.

What ioctls the kernel reports is actually a function of several things:
- The memory type
- Kernel feature support (e.g., no writeprotect on aarch64)
- The registration type (e.g., CONTINUE only supported for MINOR mode)

So, we can't fully compute this at the start, in set_test_type.  It
varies per test, depending on what registration mode(s) those tests use.

Instead, introduce a new function which computes the correct list.  This
centralizes the add/remove of ioctls depending on these function inputs
in one place, so we don't have to repeat ourselves in various tests.

Not only is the resulting code a bit shorter, but it fixes a real bug in
the existing code: previously, we would incorrectly require the
writeprotect ioctl to be present on aarch64, where it isn't actually
supported.

Link: https://lkml.kernel.org/r/20210930212309.4001967-4-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen 
Reviewed-by: Peter Xu 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

userfaultfd/selftests: fix feature support detection

2021-11-06T20:30:39+00:00

Before any tests are run, in set_test_type, we decide what feature(s) we
are going to be testing, based upon our command line arguments.
However, the supported features are not just a function of the memory
type being used, so this is broken.

For instance, consider writeprotect support.  It is "normally" supported
for anonymous memory, but furthermore it requires that the kernel has
CONFIG_HAVE_ARCH_USERFAULTFD_WP.  So, it is *not* supported at all on
aarch64, for example.

So, this fixes this by querying the kernel for the set of features it
supports in set_test_type, by opening a userfaultfd and issuing a
UFFDIO_API ioctl.  Based upon the reported features, we toggle what
tests are enabled.

Link: https://lkml.kernel.org/r/20210930212309.4001967-3-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen 
Reviewed-by: Peter Xu 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

userfaultfd/selftests: don't rely on GNU extensions for random numbers

2021-11-06T20:30:39+00:00

Patch series "Small userfaultfd selftest fixups", v2.

This patch (of 3):

Two arguments for doing this:

First, and maybe most importantly, the resulting code is significantly
shorter / simpler.

Then, we avoid using GNU libc extensions.  Why does this matter? It
makes testing userfaultfd with the selftest easier e.g.  on distros
which use something other than glibc (e.g., Alpine, which uses musl);
basically, it makes the test more portable.

Link: https://lkml.kernel.org/r/20210930212309.4001967-2-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen 
Reviewed-by: Peter Xu 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: remove duplicate include in hugepage-mremap.c

2021-11-06T20:30:39+00:00

Remove duplicate includes 'unistd.h' included in
 '/tools/testing/selftests/vm/hugepage-mremap.c'  is duplicated.It is also
 included on 23 line.

Link: https://lkml.kernel.org/r/20211018102336.869726-1-ran.jianping@zte.com.cn
Signed-off-by: Ran Jianping 
Reported-by: Zeal Robot 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm, hugepages: add hugetlb vma mremap() test

2021-11-06T20:30:39+00:00

[almasrymina@google.com: v8]
  Link: https://lkml.kernel.org/r/20211014200542.4126947-2-almasrymina@google.com
[wanjiabing@vivo.com: remove duplicated include in hugepage-mremap]
  Link: https://lkml.kernel.org/r/20211021122944.8857-1-wanjiabing@vivo.com

Link: https://lkml.kernel.org/r/20211013195825.3058275-2-almasrymina@google.com
Signed-off-by: Mina Almasry 
Signed-off-by: Wan Jiabing 
Acked-by: Mike Kravetz 
Cc: Ken Chen 
Cc: Chris Kennelly 
Cc: Michal Hocko 
Cc: Vlastimil Babka 
Cc: Kirill Shutemov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds