[PATCH 3/3] selftests/bpf: Test large allocations for both sleepable/nonsleepable arena users

[Emil Tsalapatis <emil@etsalapatis.com>]

We now use different code paths in the internal allocator when
allocating arena memory, depending on whether the caller is sleepable
or not. These paths mostly differ functionally for large allocations,
so add extra testing for that case.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
---
 .../bpf/progs/verifier_arena_large.c          | 27 ++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/progs/verifier_arena_large.c b/tools/testing/selftests/bpf/progs/verifier_arena_large.c
index 6ab8730d4878..e388a67d9129 100644
--- a/tools/testing/selftests/bpf/progs/verifier_arena_large.c
+++ b/tools/testing/selftests/bpf/progs/verifier_arena_large.c
@@ -284,6 +284,7 @@ int big_alloc2(void *ctx)
 	return 0;
 }
 
+/* Nonsleepable because it binds to a socket program. */
 SEC("socket")
 __success __retval(0)
 int big_alloc3(void *ctx)
@@ -300,7 +301,31 @@ int big_alloc3(void *ctx)
 	 */
 	pages = bpf_arena_alloc_pages(&arena, NULL, 2051, NUMA_NO_NODE, 0);
 	if (!pages)
-		return 0;
+		return 1;
+
+	bpf_for(i, 0, 2051)
+			pages[i * PAGE_SIZE] = 123;
+	bpf_for(i, 0, 2051)
+			if (pages[i * PAGE_SIZE] != 123)
+				return i;
+
+	bpf_arena_free_pages(&arena, pages, 2051);
+#endif
+	return 0;
+}
+
+/* SYSCALL programs are always sleepable. */
+SEC("syscall")
+__success __retval(0)
+int big_alloc4(void *ctx)
+{
+#if defined(__BPF_FEATURE_ADDR_SPACE_CAST)
+	char __arena *pages;
+	u64 i;
+
+	pages = bpf_arena_alloc_pages(&arena, NULL, 2051, NUMA_NO_NODE, 0);
+	if (!pages)
+		return 1;
 
 	bpf_for(i, 0, 2051)
 			pages[i * PAGE_SIZE] = 123;
-- 
2.54.0