Re: [PATCH v2 2/3] selftests/resctrl: Simplify cleanup in ctrl-c handler

[Maciej Wieczor-Retman]

On 2024-02-22 at 12:12:44 +0200, Ilpo Järvinen wrote:
>On Thu, 22 Feb 2024, Maciej Wieczor-Retman wrote:
>
>> Ctrl-c handler isn't aware of what test is currently running. Because of
>> that it executes all cleanups even if they aren't necessary. Since the
>> ctrl-c handler uses the sa_sigaction system no parameters can be passed
>> to it as function arguments.
>> 
>> Add a global variable to make ctrl-c handler aware of the currently run
>> test and only execute the correct cleanup callback.
>> 
>> Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@xxxxxxxxx>
>> ---
>> Changelog v2:
>> - Remove tests_cleanup() from resctrl.h.
>> - Make current_test a const pointer only inside resctrl_val.c. (Ilpo)
>> 
>>  tools/testing/selftests/resctrl/resctrl.h       |  3 +--
>>  tools/testing/selftests/resctrl/resctrl_tests.c | 14 +++-----------
>>  tools/testing/selftests/resctrl/resctrl_val.c   |  6 ++++--
>>  3 files changed, 8 insertions(+), 15 deletions(-)
>> 
>> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
>> index 0f49df4961ea..826783b29c9d 100644
>> --- a/tools/testing/selftests/resctrl/resctrl.h
>> +++ b/tools/testing/selftests/resctrl/resctrl.h
>> @@ -153,7 +153,6 @@ int resctrl_val(const struct resctrl_test *test,
>>  		const struct user_params *uparams,
>>  		const char * const *benchmark_cmd,
>>  		struct resctrl_val_param *param);
>> -void tests_cleanup(void);
>>  void mbm_test_cleanup(void);
>>  void mba_test_cleanup(void);
>>  unsigned long create_bit_mask(unsigned int start, unsigned int len);
>> @@ -162,7 +161,7 @@ int get_full_cbm(const char *cache_type, unsigned long *mask);
>>  int get_mask_no_shareable(const char *cache_type, unsigned long *mask);
>>  int get_cache_size(int cpu_no, const char *cache_type, unsigned long *cache_size);
>>  void ctrlc_handler(int signum, siginfo_t *info, void *ptr);
>> -int signal_handler_register(void);
>> +int signal_handler_register(const struct resctrl_test *test);
>>  void signal_handler_unregister(void);
>>  void cat_test_cleanup(void);
>>  unsigned int count_bits(unsigned long n);
>> diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
>> index 75fc49ba3efb..161f5365b4f0 100644
>> --- a/tools/testing/selftests/resctrl/resctrl_tests.c
>> +++ b/tools/testing/selftests/resctrl/resctrl_tests.c
>> @@ -75,19 +75,11 @@ static void cmd_help(void)
>>  	printf("\t-h: help\n");
>>  }
>>  
>> -void tests_cleanup(void)
>> -{
>> -	mbm_test_cleanup();
>> -	mba_test_cleanup();
>> -	cmt_test_cleanup();
>> -	cat_test_cleanup();
>> -}
>> -
>> -static int test_prepare(void)
>> +static int test_prepare(const struct resctrl_test *test)
>>  {
>>  	int res;
>>  
>> -	res = signal_handler_register();
>> +	res = signal_handler_register(test);
>>  	if (res) {
>>  		ksft_print_msg("Failed to register signal handler\n");
>>  		return res;
>> @@ -130,7 +122,7 @@ static void run_single_test(const struct resctrl_test *test, const struct user_p
>>  
>>  	ksft_print_msg("Starting %s test ...\n", test->name);
>>  
>> -	if (test_prepare()) {
>> +	if (test_prepare(test)) {
>>  		ksft_exit_fail_msg("Abnormal failure when preparing for the test\n");
>>  		return;
>>  	}
>> diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
>> index 5a49f07a6c85..d572815436f3 100644
>> --- a/tools/testing/selftests/resctrl/resctrl_val.c
>> +++ b/tools/testing/selftests/resctrl/resctrl_val.c
>> @@ -62,6 +62,7 @@ struct imc_counter_config {
>>  static char mbm_total_path[1024];
>>  static int imcs;
>>  static struct imc_counter_config imc_counters_config[MAX_IMCS][2];
>> +const struct resctrl_test *current_test;
>
>static const struct

Okay, I'll add it.

>
>>  void membw_initialize_perf_event_attr(int i, int j)
>>  {
>> @@ -472,7 +473,7 @@ void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
>>  	if (bm_pid)
>>  		kill(bm_pid, SIGKILL);
>>  	umount_resctrlfs();
>> -	tests_cleanup();
>> +	current_test->cleanup();
>
>These calls should have if (current_test->cleanup()) guard. Isn't the 
>non-contiguous already test w/o the cleanup function?

Yes, I remembered to put the check in the main test function but I forgot to put
the check here too, thanks.

I'll just resend the corrected version today.

>
>Other than those two, this looked okay.
>
>-- 
> i.
>

-- 
Kind regards
Maciej Wieczór-Retman