[PATCH RESEND 8/9] selftests/mm: mremap_test: remove validation threshold

[Sarthak Sharma <sarthak.sharma@arm.com>]

mremap_test validates only the first 4MB of large mappings by default.
The amount of data validated can be changed using the -t command line
option, with zero selecting the complete region.

Remove the validation threshold and its command line option. Always
initialize and validate the complete remapped region.

Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 tools/testing/selftests/mm/mremap_test.c | 84 +++---------------------
 1 file changed, 8 insertions(+), 76 deletions(-)

diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c
index 04ea072f8cd1..77e952556be1 100644
--- a/tools/testing/selftests/mm/mremap_test.c
+++ b/tools/testing/selftests/mm/mremap_test.c
@@ -22,13 +22,6 @@
 #define EXPECT_FAILURE 1
 #define NON_OVERLAPPING 0
 #define OVERLAPPING 1
-#define VALIDATION_DEFAULT_THRESHOLD 4	/* 4MB */
-#define VALIDATION_NO_THRESHOLD 0	/* Verify the entire region */
-
-#ifndef MIN
-#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
-#define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
-#endif
 #define SIZE_MB(m) ((size_t)m * (1024 * 1024))
 #define SIZE_KB(k) ((size_t)k * 1024)
 
@@ -61,7 +54,7 @@ enum {
 };
 
 static uint32_t *pattern;
-static size_t pattern_size;
+static const size_t pattern_size = _2GB;
 
 #define PTE page_size
 
@@ -895,19 +888,13 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, unsigned long page_siz
 }
 #endif /* __NR_userfaultfd */
 
-static int remap_region(struct config c, unsigned int threshold_mb)
+static int remap_region(struct config c)
 {
 	void *addr, *tmp_addr, *src_addr, *dest_addr, *dest_preamble_addr = NULL;
 	long long align_mask, offset;
 	int ret = 0;
-	unsigned long long threshold;
 	char *preamble_pattern;
 
-	if (threshold_mb == VALIDATION_NO_THRESHOLD)
-		threshold = c.region_size;
-	else
-		threshold = MIN(threshold_mb * _1MB, c.region_size);
-
 	src_addr = get_source_mapping(c);
 	if (!src_addr) {
 		ret = -1;
@@ -915,7 +902,7 @@ static int remap_region(struct config c, unsigned int threshold_mb)
 	}
 
 	/* Set byte pattern for source block. */
-	memcpy(src_addr, pattern, threshold);
+	memcpy(src_addr, pattern, c.region_size);
 
 	/* Mask to zero out lower bits of address for alignment */
 	align_mask = ~(c.dest_alignment - 1);
@@ -970,7 +957,7 @@ static int remap_region(struct config c, unsigned int threshold_mb)
 	}
 
 	/* Verify byte pattern after remapping */
-	if (memcmp(dest_addr, pattern, threshold)) {
+	if (memcmp(dest_addr, pattern, c.region_size)) {
 		ksft_print_msg("Data after remap doesn't match\n");
 		ret = -1;
 		goto clean_up_dest;
@@ -1059,10 +1046,9 @@ static void mremap_move_1mb_from_start(void)
 	ksft_test_result(success, "%s\n", test_name);
 }
 
-static void run_mremap_test_case(struct test test_case,
-				 unsigned int threshold_mb)
+static void run_mremap_test_case(struct test test_case)
 {
-	int ret = remap_region(test_case.config, threshold_mb);
+	int ret = remap_region(test_case.config);
 
 	if (ret < 0) {
 		if (test_case.expect_failure)
@@ -1079,38 +1065,6 @@ static void run_mremap_test_case(struct test test_case,
 	}
 }
 
-static void usage(const char *cmd)
-{
-	ksft_print_msg("Usage: %s [-t <threshold_mb>]\n", cmd);
-	ksft_print_msg("-t\t only validate threshold_mb of the remapped region\n");
-	ksft_print_msg("  \t if 0 is supplied no threshold is used; all tests\n");
-	ksft_print_msg("  \t are run and remapped regions validated fully.\n");
-	ksft_print_msg("  \t The default threshold used is 4MB.\n");
-}
-
-static int parse_args(int argc, char **argv, unsigned int *threshold_mb)
-{
-	int opt;
-
-	while ((opt = getopt(argc, argv, "t:")) != -1) {
-		switch (opt) {
-		case 't':
-			*threshold_mb = atoi(optarg);
-			break;
-		default:
-			usage(argv[0]);
-			return -1;
-		}
-	}
-
-	if (optind < argc) {
-		usage(argv[0]);
-		return -1;
-	}
-
-	return 0;
-}
-
 static void fill_pattern(uint32_t *pattern, size_t pattern_size, size_t page_size)
 {
 	size_t nr_pages = pattern_size / page_size;
@@ -1127,16 +1081,9 @@ static void fill_pattern(uint32_t *pattern, size_t pattern_size, size_t page_siz
 }
 
 #define MAX_TEST 15
-int main(int argc, char **argv)
+int main(void)
 {
 	unsigned int i;
-	unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD;
-
-	/* hard-coded test configs */
-	size_t max_test_variable_region_size = _2GB;
-	size_t max_test_constant_region_size = _2MB;
-	size_t dest_preamble_size = 10 * _4MB;
-
 	int num_expand_tests = 2;
 	int num_misc_tests = 9;
 	struct test test_cases[MAX_TEST] = {};
@@ -1147,24 +1094,9 @@ int main(int argc, char **argv)
 
 	get_mmap_min_addr();
 
-	if (parse_args(argc, argv, &threshold_mb) < 0)
-		ksft_exit_fail_msg("Invalid arguments\n");
-
-	ksft_print_msg("Test configs:\n");
-	ksft_print_msg("threshold_mb=%u\n", threshold_mb);
-
 	/*
 	 * Set a preallocated array where page[i] contains i+1
 	 */
-	if (!threshold_mb)
-		pattern_size = MAX(max_test_variable_region_size,
-				   max_test_constant_region_size);
-	else
-		pattern_size = MAX(MIN(threshold_mb * _1MB,
-				       max_test_variable_region_size),
-				   max_test_constant_region_size);
-	pattern_size = MAX(dest_preamble_size, pattern_size);
-
 	pattern = mmap(NULL, pattern_size, PROT_READ | PROT_WRITE,
 		       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 	if (pattern == MAP_FAILED) {
@@ -1229,7 +1161,7 @@ int main(int argc, char **argv)
 	ksft_set_plan(ARRAY_SIZE(test_cases) + num_expand_tests + num_misc_tests);
 
 	for (i = 0; i < ARRAY_SIZE(test_cases); i++)
-		run_mremap_test_case(test_cases[i], threshold_mb);
+		run_mremap_test_case(test_cases[i]);
 
 	maps_fp = fopen("/proc/self/maps", "r");
 
-- 
2.53.0