Re: [PATCH v5 3/4] selftest/mm: test enable_soft_offline behaviors

[Miaohe Lin <linmiaohe@huawei.com>]

On 2024/6/25 0:33, Jiaqi Yan wrote:
> Add regression and new tests when hugepage has correctable memory
...
> diff --git a/tools/testing/selftests/mm/hugetlb-soft-offline.c b/tools/testing/selftests/mm/hugetlb-soft-offline.c
> new file mode 100644
> index 000000000000..16fe52f972e2
> --- /dev/null
> +++ b/tools/testing/selftests/mm/hugetlb-soft-offline.c
> @@ -0,0 +1,227 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Test soft offline behavior for HugeTLB pages:
> + * - if enable_soft_offline = 0, hugepages should stay intact and soft
> + *   offlining failed with EINVAL.

s/failed with EINVAL/failed with EOPNOTSUPP/g

> + * - if enable_soft_offline = 1, a hugepage should be dissolved and
> + *   nr_hugepages/free_hugepages should be reduced by 1.
> + *
> + * Before running, make sure more than 2 hugepages of default_hugepagesz
> + * are allocated. For example, if /proc/meminfo/Hugepagesize is 2048kB:
> + *   echo 8 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
> + */
> +
...
> +static void test_soft_offline_common(int enable_soft_offline)
> +{
> +	int fd;
> +	int expect_errno = enable_soft_offline ? 0 : EOPNOTSUPP;
> +	struct statfs file_stat;
> +	unsigned long hugepagesize_kb = 0;
> +	unsigned long nr_hugepages_before = 0;
> +	unsigned long nr_hugepages_after = 0;
> +	int ret;
> +
> +	ksft_print_msg("Test soft-offline when enabled_soft_offline=%d\n",
> +		       enable_soft_offline);
> +
> +	fd = create_hugetlbfs_file(&file_stat);
> +	if (fd < 0) {
> +		ksft_exit_fail_msg("Failed to create hugetlbfs file\n");
> +		return;
> +	}
> +
> +	hugepagesize_kb = file_stat.f_bsize / 1024;
> +	ksft_print_msg("Hugepagesize is %ldkB\n", hugepagesize_kb);
> +
> +	if (set_enable_soft_offline(enable_soft_offline)) {
> +		ksft_exit_fail_msg("Failed to set enable_soft_offline\n");

Call destroy_hugetlbfs_file() in error path?

> +		return;
> +	}
> +
> +	if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_before) != 0) {
> +		ksft_exit_fail_msg("Failed to read nr_hugepages\n");
> +		return;
> +	}
> +
> +	ksft_print_msg("Before MADV_SOFT_OFFLINE nr_hugepages=%ld\n",
> +		       nr_hugepages_before);
> +
> +	ret = do_soft_offline(fd, 2 * file_stat.f_bsize, expect_errno);
> +
> +	if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_after) != 0) {
> +		ksft_exit_fail_msg("Failed to read nr_hugepages\n");
> +		return;
> +	}
> +
> +	ksft_print_msg("After MADV_SOFT_OFFLINE nr_hugepages=%ld\n",
> +		nr_hugepages_after);
> +
> +	if (enable_soft_offline) {
> +		if (nr_hugepages_before != nr_hugepages_after + 1) {
> +			ksft_test_result_fail("MADV_SOFT_OFFLINE should reduced 1 hugepage\n");
> +			return;
> +		}
> +	} else {
> +		if (nr_hugepages_before != nr_hugepages_after) {
> +			ksft_test_result_fail("MADV_SOFT_OFFLINE reduced %lu hugepages\n",
> +				nr_hugepages_before - nr_hugepages_after);
> +			return;
> +		}
> +	}
> +
> +	ksft_test_result(ret == 0,
> +			 "Test soft-offline when enabled_soft_offline=%d\n",
> +			 enable_soft_offline);

Call destroy_hugetlbfs_file() when test finished ?

Thanks.
.