[LTP] [PATCH] Fixed hugeshmat05 Test Failure with 1GB Hugepages.

[Pavithra]

Modified the test to detect large hugepage sizes (≥1GB) and adjust test
sizes accordingly.

Signed-off-by: Pavithra <pavrampu@linux.ibm.com>
---
 .../mem/hugetlb/hugeshmat/hugeshmat05.c       | 45 +++++++++++++++----
 1 file changed, 36 insertions(+), 9 deletions(-)

diff --git a/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c b/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
index 3b2ae351c..870a61ec1 100644
--- a/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
+++ b/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
@@ -37,9 +37,13 @@ void setup(void)
 {
 	page_size = getpagesize();
 	hpage_size = SAFE_READ_MEMINFO("Hugepagesize:") * 1024;
+
+	tst_res(TINFO, "Page size: %ld bytes", page_size);
+	tst_res(TINFO, "Hugepage size: %ld bytes (%ld MB)",
+		hpage_size, hpage_size / (1024 * 1024));
 }
 
-void shm_test(int size)
+void shm_test(long size)
 {
 	int shmid;
 	char *shmaddr;
@@ -56,7 +60,7 @@ void shm_test(int size)
 	}
 
 	shmaddr[0] = 1;
-	tst_res(TINFO, "allocated %d huge bytes", size);
+	tst_res(TINFO, "allocated %ld huge bytes", size);
 
 	if (shmdt((const void *)shmaddr) != 0) {
 		shmctl(shmid, IPC_RMID, NULL);
@@ -69,16 +73,39 @@ void shm_test(int size)
 static void test_hugeshmat(void)
 {
 	unsigned int i;
+	long tst_sizes[4];
+
+	/*
+	 * For large hugepage sizes (e.g., 1GB), we need to ensure
+	 * test sizes are within reasonable bounds and properly aligned.
+	 * The original test used N*hpage_size which could be 4GB for 1GB pages.
+	 *
+	 * We adjust the test to use N/2 multiplier for large hugepages
+	 * to avoid excessive memory requirements while still testing the
+	 * alignment boundary conditions with multiple pages.
+	 */
+	if (hpage_size >= 1024 * 1024 * 1024) {
+		/* For 1GB or larger hugepages, use N/2 pages (2 pages for N=4) */
+		long multiplier = N / 2;
 
-	const int tst_sizes[] = {
-		N * hpage_size - page_size,
-		N * hpage_size - page_size - 1,
-		hpage_size,
-		hpage_size + 1
-	};
+		tst_sizes[0] = multiplier * hpage_size - page_size;
+		tst_sizes[1] = multiplier * hpage_size - page_size - 1;
+		tst_sizes[2] = hpage_size;
+		tst_sizes[3] = hpage_size + 1;
+		tst_res(TINFO, "Using N/2=%ld hugepage test sizes for large hugepages", multiplier);
+	} else {
+		/* For smaller hugepages (2MB, 16MB, etc.), use original test */
+		tst_sizes[0] = N * hpage_size - page_size;
+		tst_sizes[1] = N * hpage_size - page_size - 1;
+		tst_sizes[2] = hpage_size;
+		tst_sizes[3] = hpage_size + 1;
+		tst_res(TINFO, "Using N=%d hugepage test sizes", N);
+	}
 
-	for (i = 0; i < ARRAY_SIZE(tst_sizes); ++i)
+	for (i = 0; i < ARRAY_SIZE(tst_sizes); ++i) {
+		tst_res(TINFO, "Testing size: %ld bytes", tst_sizes[i]);
 		shm_test(tst_sizes[i]);
+	}
 
 	tst_res(TPASS, "No regression found.");
 }
-- 
2.53.0