On Fri, Nov 5, 2021 at 9:25 AM Anders Roxell <anders.roxell@xxxxxxxxxx> wrote:
>
> When building selftests/cgroup with clang, the compiler warn about the
> function abs() see below:
>
> In file included from test_memcontrol.c:21:
> ./cgroup_util.h:16:9: warning: absolute value function 'abs' given an argument of type 'long' but has parameter of type 'int' which may cause truncation of value [-Wabsolute-value]
> return abs(a - b) <= (a + b) / 100 * err;
> ^
> ./cgroup_util.h:16:9: note: use function 'labs' instead
> return abs(a - b) <= (a + b) / 100 * err;
> ^~~
> labs
>
> The note indicates what to do, Rework to use the function 'labs()'.
>
> Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
Thanks for the patch!
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> ---
> tools/testing/selftests/cgroup/cgroup_util.h | 2 +-
> tools/testing/selftests/cgroup/test_kmem.c | 4 ++--
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/tools/testing/selftests/cgroup/cgroup_util.h b/tools/testing/selftests/cgroup/cgroup_util.h
> index 82e59cdf16e7..76b35d9dffb5 100644
> --- a/tools/testing/selftests/cgroup/cgroup_util.h
> +++ b/tools/testing/selftests/cgroup/cgroup_util.h
> @@ -13,7 +13,7 @@
> */
> static inline int values_close(long a, long b, int err)
> {
> - return abs(a - b) <= (a + b) / 100 * err;
> + return labs(a - b) <= (a + b) / 100 * err;
> }
>
> extern int cg_find_unified_root(char *root, size_t len);
> diff --git a/tools/testing/selftests/cgroup/test_kmem.c b/tools/testing/selftests/cgroup/test_kmem.c
> index 22b31ebb3513..d65bb8fe876a 100644
> --- a/tools/testing/selftests/cgroup/test_kmem.c
> +++ b/tools/testing/selftests/cgroup/test_kmem.c
> @@ -192,7 +192,7 @@ static int test_kmem_memcg_deletion(const char *root)
> goto cleanup;
>
> sum = slab + anon + file + kernel_stack + pagetables + percpu + sock;
> - if (abs(sum - current) < MAX_VMSTAT_ERROR) {
> + if (labs(sum - current) < MAX_VMSTAT_ERROR) {
> ret = KSFT_PASS;
> } else {
> printf("memory.current = %ld\n", current);
> @@ -383,7 +383,7 @@ static int test_percpu_basic(const char *root)
> current = cg_read_long(parent, "memory.current");
> percpu = cg_read_key_long(parent, "memory.stat", "percpu ");
>
> - if (current > 0 && percpu > 0 && abs(current - percpu) <
> + if (current > 0 && percpu > 0 && labs(current - percpu) <
> MAX_VMSTAT_ERROR)
> ret = KSFT_PASS;
> else
> --
> 2.33.0
>
--
Thanks,
~Nick Desaulniers
