On Wed, 8 May 2024, John Hubbard wrote:
> When building with clang, via:
>
> make LLVM=1 -C tools/testing/selftests
>
> ...two types of warnings occur:
>
> warning: absolute value function 'abs' given an argument of type
> 'long' but has parameter of type 'int' which may cause truncation of
> value
>
> warning: taking the absolute value of unsigned type 'unsigned long'
> has no effect
>
> Fix these by:
>
> a) using labs() in place of abs(), when long integers are involved, and
>
> b) Change to use signed integer data types, in places where subtraction
> is used (and could end up with negative values).
>
> c) Remove a duplicate abs() call in cmt_test.c.
In general, instead of filename, it's better to refer to the actual
function in this kind of description. And in this particular case,
cmt_test.c could be replaced with "the CMT selftest" which is more
descriptive and still unambiguous.
> Cc: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> Cc: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
Thank you.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
--
i.
> ---
> tools/testing/selftests/resctrl/cmt_test.c | 4 ++--
> tools/testing/selftests/resctrl/mba_test.c | 2 +-
> tools/testing/selftests/resctrl/mbm_test.c | 2 +-
> 3 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c
> index a81f91222a89..05a241519ae8 100644
> --- a/tools/testing/selftests/resctrl/cmt_test.c
> +++ b/tools/testing/selftests/resctrl/cmt_test.c
> @@ -40,11 +40,11 @@ static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
> int ret;
>
> avg_llc_val = sum_llc_val / num_of_runs;
> - avg_diff = (long)abs(cache_span - avg_llc_val);
> + avg_diff = (long)(cache_span - avg_llc_val);
> diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;
>
> ret = platform && abs((int)diff_percent) > max_diff_percent &&
> - abs(avg_diff) > max_diff;
> + labs(avg_diff) > max_diff;
>
> ksft_print_msg("%s Check cache miss rate within %lu%%\n",
> ret ? "Fail:" : "Pass:", max_diff_percent);
> diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
> index 7946e32e85c8..5fffbc9ff6a4 100644
> --- a/tools/testing/selftests/resctrl/mba_test.c
> +++ b/tools/testing/selftests/resctrl/mba_test.c
> @@ -60,7 +60,7 @@ static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
> /* Memory bandwidth from 100% down to 10% */
> for (allocation = 0; allocation < ALLOCATION_MAX / ALLOCATION_STEP;
> allocation++) {
> - unsigned long avg_bw_imc, avg_bw_resc;
> + long avg_bw_imc, avg_bw_resc;
> unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
> int avg_diff_per;
> float avg_diff;
> diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
> index d67ffa3ec63a..a4c3ea49b0e8 100644
> --- a/tools/testing/selftests/resctrl/mbm_test.c
> +++ b/tools/testing/selftests/resctrl/mbm_test.c
> @@ -17,7 +17,7 @@
> static int
> show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, size_t span)
> {
> - unsigned long avg_bw_imc = 0, avg_bw_resc = 0;
> + long avg_bw_imc = 0, avg_bw_resc = 0;
> unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
> int runs, ret, avg_diff_per;
> float avg_diff = 0;
>
> base-commit: 45db3ab70092637967967bfd8e6144017638563c
> prerequisite-patch-id: b901ece2a5b78503e2fb5480f20e304d36a0ea27
> prerequisite-patch-id: 8d96c4b8c3ed6d9ea2588ef7f594ae0f9f83c279
>
