[PATCH v6 3/3] kselftest: mm: remove check_huge_shmem()

[Yeoreum Yun <yeoreum.yun@arm.com>]

check_huge_shmem() was required to distinguish shmem huge pages because
/proc/self/smaps reports them using a dedicated “ShmemPmdMapped” entry,
as opposed to “FilePmdMapped” for file-backed huge pages.

Now that /proc/self/smaps is no longer used to detect huge pages and
/proc/kpageflags is used instead, it is sufficient to distinguish
between file-backed and anonymous pages since the ShmemPmdMapped is also
kind of file-backed.

Therefore, remove check_huge_shmem() and use check_huge_file() instead.

Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
---
 tools/testing/selftests/mm/folio_split_race_test.c |  2 +-
 tools/testing/selftests/mm/khugepaged.c            |  5 ++---
 tools/testing/selftests/mm/uffd-common.c           |  4 ++--
 tools/testing/selftests/mm/vm_util.c               | 11 +----------
 tools/testing/selftests/mm/vm_util.h               |  2 --
 5 files changed, 6 insertions(+), 18 deletions(-)

diff --git a/tools/testing/selftests/mm/folio_split_race_test.c b/tools/testing/selftests/mm/folio_split_race_test.c
index 1960635a953e..4c0d3b6a411b 100644
--- a/tools/testing/selftests/mm/folio_split_race_test.c
+++ b/tools/testing/selftests/mm/folio_split_race_test.c
@@ -182,7 +182,7 @@ static uint64_t run_iteration(void)
 	for (i = 0; i < TOTAL_PAGES; i++)
 		fill_page(mmap_base, i);
 
-	if (!check_huge_shmem(mmap_base, FILE_SIZE, NR_PMD_PAGE, pmd_pagesize))
+	if (!check_huge_file(mmap_base, FILE_SIZE, NR_PMD_PAGE, pmd_pagesize))
 		ksft_exit_fail_msg("No shmem THP is allocated\n");
 
 	if (pthread_barrier_init(&ctl.barrier, NULL, NUM_READER_THREADS + 1) != 0)
diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
index f82673f5f6b4..6cd1effea465 100644
--- a/tools/testing/selftests/mm/khugepaged.c
+++ b/tools/testing/selftests/mm/khugepaged.c
@@ -416,9 +416,8 @@ static bool file_check_huge(void *addr, size_t len, int nr_hpages,
 {
 	switch (finfo.type) {
 	case VMA_FILE:
-		return check_huge_file(addr, len, nr_hpages, hpage_size);
 	case VMA_SHMEM:
-		return check_huge_shmem(addr, len, nr_hpages, hpage_size);
+		return check_huge_file(addr, len, nr_hpages, hpage_size);
 	default:
 		ksft_exit_fail_msg("Unknown VMA type\n");
 		return false;
@@ -451,7 +450,7 @@ static void shmem_cleanup_area(void *p, unsigned long size)
 static bool shmem_check_huge(void *addr, size_t len, int nr_hpages,
 		unsigned long hpage_size)
 {
-	return check_huge_shmem(addr, len, nr_hpages, hpage_size);
+	return check_huge_file(addr, len, nr_hpages, hpage_size);
 }
 
 static struct mem_ops __anon_ops = {
diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c
index 1fb967ef4985..a76851aced4d 100644
--- a/tools/testing/selftests/mm/uffd-common.c
+++ b/tools/testing/selftests/mm/uffd-common.c
@@ -196,8 +196,8 @@ static void shmem_check_pmd_mapping(uffd_global_test_opts_t *gopts, void *p, int
 {
 	size_t len = expect_nr_hpages * read_pmd_pagesize();
 
-	if (!check_huge_shmem(gopts->area_dst_alias, len, expect_nr_hpages,
-			      read_pmd_pagesize()))
+	if (!check_huge_file(gopts->area_dst_alias, len, expect_nr_hpages,
+			     read_pmd_pagesize()))
 		err("Did not find expected %d number of hugepages",
 		    expect_nr_hpages);
 }
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index 98f110098179..e31e88d5af76 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -384,22 +384,18 @@ static bool check_large_folios(int pagemap_fd, int kpageflags_fd,
 enum check_huge_type {
 	CHECK_HUGE_ANON,
 	CHECK_HUGE_FILE,
-	CHECK_HUGE_SHMEM,
 };
 
 static bool check_huge_type(uint64_t categories, uint64_t kpageflags,
 			    enum check_huge_type type)
 {
 	const bool file = categories & PAGE_IS_FILE;
-	const bool swapbacked = kpageflags & KPF_SWAPBACKED;
 
 	switch (type) {
 	case CHECK_HUGE_ANON:
 		return !file;
 	case CHECK_HUGE_FILE:
-		return file && !swapbacked;
-	case CHECK_HUGE_SHMEM:
-		return file && swapbacked;
+		return file;
 	}
 
 	return false;
@@ -479,11 +475,6 @@ bool check_huge_file(void *addr, size_t len, int nr_hpages, uint64_t hpage_size)
 	return __check_huge(addr, len, nr_hpages, hpage_size, CHECK_HUGE_FILE);
 }
 
-bool check_huge_shmem(void *addr, size_t len, int nr_hpages, uint64_t hpage_size)
-{
-	return __check_huge(addr, len, nr_hpages, hpage_size, CHECK_HUGE_SHMEM);
-}
-
 int64_t allocate_transhuge(void *ptr, int pagemap_fd)
 {
 	uint64_t ent[2];
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index f19bd17817e5..fc9c93235f6f 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -18,7 +18,6 @@
 #define PM_SWAP                       BIT_ULL(62)
 #define PM_PRESENT                    BIT_ULL(63)
 
-#define KPF_SWAPBACKED                BIT_ULL(14)
 #define KPF_COMPOUND_HEAD             BIT_ULL(15)
 #define KPF_COMPOUND_TAIL             BIT_ULL(16)
 #define KPF_HWPOISON                  BIT_ULL(19)
@@ -93,7 +92,6 @@ uint64_t read_pmd_pagesize(void);
 unsigned long rss_anon(void);
 bool check_huge_anon(void *addr, size_t len, int nr_hpages, uint64_t hpage_size);
 bool check_huge_file(void *addr, size_t len, int nr_hpages, uint64_t hpage_size);
-bool check_huge_shmem(void *addr, size_t len, int nr_hpages, uint64_t hpage_size);
 int64_t allocate_transhuge(void *ptr, int pagemap_fd);
 int pageflags_get(unsigned long pfn, int kpageflags_fd, uint64_t *flags);
 int gather_folio_orders(char *vaddr_start, size_t len,

-- 
2.43.0