Let's test whether setting PR_SET_MEMORY_MERGE to 0 after setting it to 1
will unmerge pages, similar to how setting MADV_UNMERGEABLE after setting
MADV_MERGEABLE would.
Link: https://lkml.kernel.org/r/20230422205420.30372-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Stefan Roesch <shr@devkernel.io>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This adds three new tests to the selftests for KSM. These tests use the
new prctl API's to enable and disable KSM.
1) add new prctl flags to prctl header file in tools dir
This adds the new prctl flags to the include file prct.h in the
tools directory. This makes sure they are available for testing.
2) add KSM prctl merge test to ksm_tests
This adds the -t option to the ksm_tests program. The -t flag
allows to specify if it should use madvise or prctl ksm merging.
3) add two functions for debugging merge outcome for ksm_tests
This adds two functions to report the metrics in /proc/self/ksm_stat
and /sys/kernel/debug/mm/ksm. The debug output is enabled with the
-d option.
4) add KSM prctl test to ksm_functional_tests
This adds a test to the ksm_functional_test that verifies that the
prctl system call to enable / disable KSM works.
5) add KSM fork test to ksm_functional_test
Add fork test to verify that the MMF_VM_MERGE_ANY flag is inherited
by the child process.
Link: https://lkml.kernel.org/r/20230418051342.1919757-4-shr@devkernel.io
Signed-off-by: Stefan Roesch <shr@devkernel.io>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add two helpers to register/unregister to an uffd. Use them to drop
duplicate codes.
This patch also drops assert_expected_ioctls_present() and
get_expected_ioctls(). Reasons:
- It'll need a lot of effort to pass test_type==HUGETLB into it from
the upper, so it's the simplest way to get rid of another global var
- The ioctls returned in UFFDIO_REGISTER is hardly useful at all,
because any app can already detect kernel support on any ioctl via its
corresponding UFFD_FEATURE_*. The check here is for sanity mostly but
it's probably destined no user app will even use it.
- It's not friendly to one future goal of uffd to run on old
kernels, the problem is get_expected_ioctls() compiles against
UFFD_API_RANGE_IOCTLS, which is a value that can change depending on
where the test is compiled, rather than reflecting what the kernel
underneath has. It means it'll report false negatives on old kernels
so it's against our will.
So let's make our lives easier.
[peterx@redhat.com; tools/testing/selftests/mm/hugepage-mremap.c: add headers]
Link: https://lkml.kernel.org/r/ZDxrvZh/cw357D8P@x1n
Link: https://lkml.kernel.org/r/20230412164247.328293-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename selftets/vm to selftests/mm for being more consistent with the
code, documentation, and tools directories, and won't be confused with
virtual machines.
[sj@kernel.org: convert missing vm->mm changes]
Link: https://lkml.kernel.org/r/20230107230643.252273-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20230103180754.129637-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
