selftests/mm: hugetlb-mremap: add setup of HugeTLB pages

hugetlb-mremap test fails if there are no free huge pages prepared by a
wrapper script.

Add setup of HugeTLB pages to the test and make sure that the original
settings are restored on the test exit.

Link: https://lore.kernel.org/20260511162840.375890-42-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Tested-by: Sarthak Sharma <sarthak.sharma@arm.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam@infradead.org>
Cc: Li Wang <li.wang@linux.dev>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/mm/hugetlb-mremap.c b/tools/testing/selftests/mm/hugetlb-mremap.c
index 1c87c39780c52010e681ed697289ee78b9925c50..d239905790dd896da2b1fcf8e948a402b78aa55b 100644 (file)
--- a/tools/testing/selftests/mm/hugetlb-mremap.c
+++ b/tools/testing/selftests/mm/hugetlb-mremap.c
@@ -26,6 +26,7 @@
 #include <stdbool.h>
 #include "kselftest.h"
 #include "vm_util.h"
+#include "hugepage_settings.h"
 
 #define DEFAULT_LENGTH_MB 10UL
 #define MB_TO_BYTES(x) (x * 1024 * 1024)
@@ -108,8 +109,9 @@ static void register_region_with_uffd(char *addr, size_t len)
 
 int main(int argc, char *argv[])
 {
+       unsigned long hugepage_size;
+       int ret = 0, fd, nr;
        size_t length = 0;
-       int ret = 0, fd;
 
        ksft_print_header();
        ksft_set_plan(1);
@@ -125,7 +127,16 @@ int main(int argc, char *argv[])
        else
                length = DEFAULT_LENGTH_MB;
 
+       hugepage_size = default_huge_page_size();
+       if (!hugepage_size)
+               ksft_exit_skip("Could not detect default hugetlb page size\n");
        length = MB_TO_BYTES(length);
+       length = (length + hugepage_size - 1) & ~(hugepage_size - 1);
+       nr = length / hugepage_size;
+
+       if (!hugetlb_setup_default(nr))
+               ksft_exit_skip("Not enough huge pages\n");
+
        fd = memfd_create(argv[0], MFD_HUGETLB);
        if (fd < 0)
                ksft_exit_fail_msg("Open failed: %s\n", strerror(errno));