selftests/bpf: Fix kmem_cache iterator draining

The closing parentheses around the read syscall is misplaced, causing
single byte reads from the iterator instead of buf sized reads. While
the end result is the same, many more read calls than necessary are
performed.

$ tools/testing/selftests/bpf/vmtest.sh  "./test_progs -t kmem_cache_iter"
145/1   kmem_cache_iter/check_task_struct:OK
145/2   kmem_cache_iter/check_slabinfo:OK
145/3   kmem_cache_iter/open_coded_iter:OK
145     kmem_cache_iter:OK
Summary: 1/3 PASSED, 0 SKIPPED, 0 FAILED

Fixes: a496d0cdc8 ("selftests/bpf: Add a test for kmem_cache_iter")
Signed-off-by: T.J. Mercier <tjmercier@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://patch.msgid.link/20250428180256.1482899-1-tjmercier@google.com
This commit is contained in:
T.J. Mercier 2025-04-28 18:02:54 +00:00 • committed by Martin KaFai Lau
commit 38d976c32d