Re: [PATCH 08/24] selftests/resctrl: Split show_cache_info() to test specific and generic parts

From: Reinette Chatre <reinette.chatre@intel.com>
To: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>,
	linux-kselftest@vger.kernel.org, "Shuah Khan" <shuah@kernel.org>,
	"Shaopeng Tan" <tan.shaopeng@jp.fujitsu.com>,
	"Maciej Wieczór-Retman" <maciej.wieczor-retman@intel.com>,
	"Fenghua Yu" <fenghua.yu@intel.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 08/24] selftests/resctrl: Split show_cache_info() to test specific and generic parts
Date: Thu, 2 Nov 2023 10:48:43 -0700	[thread overview]
Message-ID: <5d504c29-896d-451a-bf85-eaef315bb822@intel.com> (raw)
In-Reply-To: <20231024092634.7122-9-ilpo.jarvinen@linux.intel.com>

Hi Ilpo,

On 10/24/2023 2:26 AM, Ilpo Järvinen wrote:
> show_cache_info() calculates results and provides generic cache
> information. This makes it hard to alter pass/fail conditions.
> 
> Separate the test specific checks into CAT and CMT test files and
> leave only the generic information part into show_cache_info().
> 
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> ---
>  tools/testing/selftests/resctrl/cache.c    | 40 ++++------------------
>  tools/testing/selftests/resctrl/cat_test.c | 30 ++++++++++++++--
>  tools/testing/selftests/resctrl/cmt_test.c | 32 +++++++++++++++--
>  tools/testing/selftests/resctrl/resctrl.h  |  6 ++--
>  4 files changed, 65 insertions(+), 43 deletions(-)
> 
> diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c
> index 299d9508221f..95489d4b42b7 100644
> --- a/tools/testing/selftests/resctrl/cache.c
> +++ b/tools/testing/selftests/resctrl/cache.c
> @@ -267,43 +267,17 @@ int cat_val(struct resctrl_val_param *param, size_t span)
>  }
>  
>  /*
> - * show_cache_info:	show cache test result information
> - * @sum_llc_val:	sum of LLC cache result data
> + * show_cache_info:	show generic cache test information
>   * @no_of_bits:		number of bits
> - * @cache_span:		cache span in bytes for CMT or in lines for CAT
> - * @max_diff:		max difference
> - * @max_diff_percent:	max difference percentage
> - * @num_of_runs:	number of runs
> - * @platform:		show test information on this platform
> - * @cmt:		CMT test or CAT test
> - *
> - * Return:		0 on success. non-zero on failure.
> + * @avg_llc_val:	avg of LLC cache result data
> + * @cache_span:		cache span
> + * @lines:		cache span in lines or bytes

It may be helpful to directly connect it to the other parameter:
	@cache_span in lines or bytes

>   */
> -int show_cache_info(unsigned long sum_llc_val, int no_of_bits,
> -		    size_t cache_span, unsigned long max_diff,
> -		    unsigned long max_diff_percent, unsigned long num_of_runs,
> -		    bool platform, bool cmt)
> +void show_cache_info(int no_of_bits, unsigned long avg_llc_val,
> +		     size_t cache_span, bool lines)
>  {
> -	unsigned long avg_llc_val = 0;
> -	float diff_percent;
> -	long avg_diff = 0;
> -	int ret;
> -
> -	avg_llc_val = sum_llc_val / num_of_runs;
> -	avg_diff = (long)abs(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 &&
> -	      (cmt ? (abs(avg_diff) > max_diff) : true);
> -
> -	ksft_print_msg("%s Check cache miss rate within %lu%%\n",
> -		       ret ? "Fail:" : "Pass:", max_diff_percent);
> -
> -	ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));
>  	ksft_print_msg("Number of bits: %d\n", no_of_bits);
>  	ksft_print_msg("Average LLC val: %lu\n", avg_llc_val);
> -	ksft_print_msg("Cache span (%s): %zu\n", cmt ? "bytes" : "lines",
> +	ksft_print_msg("Cache span (%s): %zu\n", !lines ? "bytes" : "lines",
>  		       cache_span);

I think it would be easier to read as: lines ? "lines" : "bytes"

Reinette