The nr_hugepgs variable is used to keep the original nr_hugepages at the hugepage setup step at test beginning. After userfaultfd test, a cleaup is executed, both /sys/kernel/mm/hugepages/hugepages-*/nr_hugepages and /proc/sys//vm/nr_hugepages are reset to 'original' value before userfaultfd test starts.
Issue here is the value used to restore /proc/sys/vm/nr_hugepages is nr_hugepgs which is the initial value before the vm_runtests.sh runs, not the value before userfaultfd test starts. 'va_high_addr_swith.sh' tests runs after that will possibly see no hugepages available for test, and got EINVAL when mmap(HUGETLB), making the result invalid. And before pkey tests, nr_hugepgs is changed to be used as a temp variable to save nr_hugepages before pkey test, and restore it after pkey tests finish. The original nr_hugepages value is not tracked anymore, so no way to restore it after all tests finish. Add a new variable nr_hugepgs_origin to save the original nr_hugepages, and and restore it to nr_hugepages after all tests finish. And change to use the nr_hugepgs variable to save the /proc/sys/vm/nr_hugeages after hugepage setup, it's also the value before userfaultfd test starts, and the correct value to be restored after userfaultfd finishes. The va_high_addr_switch.sh broken will be resolved. Signed-off-by: Chunyu Hu <ch...@redhat.com> --- tools/testing/selftests/mm/run_vmtests.sh | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh index 471e539d82b8..f1a7ad3ec6a7 100755 --- a/tools/testing/selftests/mm/run_vmtests.sh +++ b/tools/testing/selftests/mm/run_vmtests.sh @@ -172,13 +172,13 @@ fi # set proper nr_hugepages if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then - nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages) + nr_hugepgs_origin=$(cat /proc/sys/vm/nr_hugepages) needpgs=$((needmem_KB / hpgsize_KB)) tries=2 while [ "$tries" -gt 0 ] && [ "$freepgs" -lt "$needpgs" ]; do lackpgs=$((needpgs - freepgs)) echo 3 > /proc/sys/vm/drop_caches - if ! echo $((lackpgs + nr_hugepgs)) > /proc/sys/vm/nr_hugepages; then + if ! echo $((lackpgs + nr_hugepgs_origin)) > /proc/sys/vm/nr_hugepages; then echo "Please run this test as root" exit $ksft_skip fi @@ -189,6 +189,7 @@ if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then done < /proc/meminfo tries=$((tries - 1)) done + nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages) if [ "$freepgs" -lt "$needpgs" ]; then printf "Not enough huge pages available (%d < %d)\n" \ "$freepgs" "$needpgs" @@ -532,6 +533,10 @@ CATEGORY="page_frag" run_test ./test_page_frag.sh aligned CATEGORY="page_frag" run_test ./test_page_frag.sh nonaligned +if [ "${HAVE_HUGEPAGES}" = 1 ]; then + echo "$nr_hugepgs_origin" > /proc/sys/vm/nr_hugepages +fi + echo "SUMMARY: PASS=${count_pass} SKIP=${count_skip} FAIL=${count_fail}" | tap_prefix echo "1..${count_total}" | tap_output -- 2.49.0