[PATCH] kcsan: use u64 instead of cycles_t

Heiko Carstens
2021-07-29T14:28:21Z

cycles_t has a different type across architectures: unsigned int,
unsinged long, or unsigned long long. Depending on architecture this
will generate this warning:

kernel/kcsan/debugfs.c: In function ‘microbenchmark’:
./include/linux/kern_levels.h:5:25: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘cycles_t’ {aka ‘long unsigned int’} [-Wformat=]

To avoid this simple change the type of cycle to u64 in
microbenchmark(), since u64 is of type unsigned long long for all
architectures.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
kernel/kcsan/debugfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/kcsan/debugfs.c b/kernel/kcsan/debugfs.c
index e65de172ccf7..1d1d1b0e4248 100644
--- a/kernel/kcsan/debugfs.c
+++ b/kernel/kcsan/debugfs.c
@@ -64,7 +64,7 @@ static noinline void microbenchmark(unsigned long iters)
{
const struct kcsan_ctx ctx_save = current->kcsan_ctx;
const bool was_enabled = READ_ONCE(kcsan_enabled);
- cycles_t cycles;
+ u64 cycles;

/* We may have been called from an atomic region; reset context. */
memset(&current->kcsan_ctx, 0, sizeof(current->kcsan_ctx));
--
2.25.1