diff options
| author | David Hildenbrand <david@redhat.com> | 2022-10-21 13:11:36 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-12-12 05:12:07 +0300 |
| commit | 93fb70aa5904c2577fab8100fa990ecfa4f5b4c7 (patch) | |
| tree | 4124641b982864c743a18a6b8c9d75823965f54a /tools/testing/selftests/vm/Makefile | |
| parent | 85463321e726fe59873bbc21f2f480747810aef8 (diff) | |
| download | linux-93fb70aa5904c2577fab8100fa990ecfa4f5b4c7.tar.xz | |
selftests/vm: add KSM unmerge tests
Patch series "mm/ksm: break_ksm() cleanups and fixes", v2.
This series cleans up and fixes break_ksm(). In summary, we no longer use
fake write faults to break COW but instead FAULT_FLAG_UNSHARE. Further,
we move away from using follow_page() --- that we can hopefully remove
completely at one point --- and use new walk_page_range_vma() instead.
Fortunately, we can get rid of VM_FAULT_WRITE and FOLL_MIGRATION in common
code now.
Extend the existing ksm tests by an unmerge benchmark, and a some new
unmerge tests.
Also, add a selftest to measure MADV_UNMERGEABLE performance. In my setup
(AMD Ryzen 9 3900X), running the KSM selftest to test unmerge performance
on 2 GiB (taskset 0x8 ./ksm_tests -D -s 2048), this results in a
performance degradation of ~6% -- 7% (old: ~5250 MiB/s, new: ~4900 MiB/s).
I don't think we particularly care for now, but it's good to be aware of
the implication.
This patch (of 9):
Let's add three unmerge tests (MADV_UNMERGEABLE unmerging all pages in the
range).
test_unmerge(): basic unmerge tests
test_unmerge_discarded(): have some pte_none() entries in the range
test_unmerge_uffd_wp(): protect the merged pages using uffd-wp
ksm_tests.c currently contains a mixture of benchmarks and tests, whereby
each test is carried out by executing the ksm_tests binary with specific
parameters. Let's add new ksm_functional_tests.c that performs multiple,
smaller functional tests all at once.
Link: https://lkml.kernel.org/r/20221021101141.84170-1-david@redhat.com
Link: https://lkml.kernel.org/r/20221021101141.84170-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'tools/testing/selftests/vm/Makefile')
| -rw-r--r-- | tools/testing/selftests/vm/Makefile | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index a4d764efd6e3..89c14e41bd43 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -55,6 +55,7 @@ TEST_GEN_FILES += userfaultfd TEST_GEN_PROGS += soft-dirty TEST_GEN_PROGS += split_huge_page_test TEST_GEN_FILES += ksm_tests +TEST_GEN_PROGS += ksm_functional_tests ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_32bit_program.c -m32) @@ -100,6 +101,7 @@ include ../lib.mk $(OUTPUT)/cow: vm_util.c $(OUTPUT)/khugepaged: vm_util.c +$(OUTPUT)/ksm_functional_tests: vm_util.c $(OUTPUT)/madv_populate: vm_util.c $(OUTPUT)/soft-dirty: vm_util.c $(OUTPUT)/split_huge_page_test: vm_util.c |