diff mbox series

selftests/resctrl: fix clang build warnings related to abs(), labs() calls

Message ID 20240508190254.266892-1-jhubbard@nvidia.com
State Accepted
Commit 14d28ec6f821622211aa65b4da156399c9a4a9c6
Headers show
Series selftests/resctrl: fix clang build warnings related to abs(), labs() calls | expand

Commit Message

John Hubbard May 8, 2024, 7:02 p.m. UTC
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.

Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
---
 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(-)


base-commit: 45db3ab70092637967967bfd8e6144017638563c
prerequisite-patch-id: b901ece2a5b78503e2fb5480f20e304d36a0ea27
prerequisite-patch-id: 8d96c4b8c3ed6d9ea2588ef7f594ae0f9f83c279

Comments

Ilpo Järvinen May 10, 2024, 9:06 a.m. UTC | #1
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@intel.com>
> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>

Thank you.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
John Hubbard May 10, 2024, 6:01 p.m. UTC | #2
On 5/10/24 2:06 AM, Ilpo Järvinen wrote:
> 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.

Sure, I'll change that.

> 
>> Cc: Reinette Chatre <reinette.chatre@intel.com>
>> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
>> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> 
> Thank you.
> 
> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> 

Thanks for the review!


thanks,
diff mbox series

Patch

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;