On 15.08.25 15:54, Usama Arif wrote:
The test will set the global system THP setting to never, madvise or always depending on the fixture variant and the 2M setting to inherit before it starts (and reset to original at teardown). The fixture setup will also test if PR_SET_THP_DISABLE prctl call can be made with PR_THP_DISABLE_EXCEPT_ADVISED and skip if it fails. This tests if the process can: - successfully get the policy to disable THPs expect for madvise. - get hugepages only on MADV_HUGE and MADV_COLLAPSE if the global policy is madvise/always and only with MADV_COLLAPSE if the global policy is never. - successfully reset the policy of the process. - after reset, only get hugepages with: - MADV_COLLAPSE when policy is set to never. - MADV_HUGE and MADV_COLLAPSE when policy is set to madvise. - always when policy is set to "always". - never get a THP with MADV_NOHUGEPAGE. - repeat the above tests in a forked process to make sure the policy is carried across forks. Test results: ./prctl_thp_disable TAP version 13 1..12 ok 1 prctl_thp_disable_completely.never.nofork ok 2 prctl_thp_disable_completely.never.fork ok 3 prctl_thp_disable_completely.madvise.nofork ok 4 prctl_thp_disable_completely.madvise.fork ok 5 prctl_thp_disable_completely.always.nofork ok 6 prctl_thp_disable_completely.always.fork ok 7 prctl_thp_disable_except_madvise.never.nofork ok 8 prctl_thp_disable_except_madvise.never.fork ok 9 prctl_thp_disable_except_madvise.madvise.nofork ok 10 prctl_thp_disable_except_madvise.madvise.fork ok 11 prctl_thp_disable_except_madvise.always.nofork ok 12 prctl_thp_disable_except_madvise.always.fork Signed-off-by: Usama Arif <usamaarif642@xxxxxxxxx> ---
Acked-by: David Hildenbrand <david@xxxxxxxxxx> -- Cheers David / dhildenb