Messages in this thread | | | Date | Tue, 7 May 2024 18:37:42 -0700 | Subject | Re: [PATCH v2] selftests/resctrl: fix clang build warnings related to abs(), labs() calls | From | Reinette Chatre <> |
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Hi John,
On 5/7/2024 6:25 PM, John Hubbard wrote: > On 5/7/24 6:21 PM, Reinette Chatre wrote: >> Hi John, > ... >> >> The following (what was in v1) looks good to me. What am I missing? >> >> 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); > > This deletes the abs() call, because I incorrectly let clang's warning > lead me to believe that the abs() call was a no-op. But both you and Ilpo > pointed out that the math breaks if you do that.
To me the extra abs() was unnecessary anyway ...
> >> 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; >
.. because it is repeated here.
> This hunk is OK. > >> ksft_print_msg("%s Check cache miss rate within %lu%%\n", >> ret ? "Fail:" : "Pass:", max_diff_percent); >> >> Reinette > > thanks,
Reinette
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