Re: [kvm-unit-tests PATCH v4 5/6] s390x: css: testing measurement block format 0

[Janosch Frank <frankja@linux.ibm.com>]

On 3/1/21 12:47 PM, Pierre Morel wrote:
> We test the update of the measurement block format 0, the
> measurement block origin is calculated from the mbo argument
> used by the SCHM instruction and the offset calculated using
> the measurement block index of the SCHIB.
> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> ---
>  lib/s390x/css.h | 12 +++++++++
>  s390x/css.c     | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 78 insertions(+)
> 
> diff --git a/lib/s390x/css.h b/lib/s390x/css.h
> index b8ac363..40f9efa 100644
> --- a/lib/s390x/css.h
> +++ b/lib/s390x/css.h
> @@ -375,4 +375,16 @@ static inline void schm(void *mbo, unsigned int flags)
>  bool css_enable_mb(int sid, uint64_t mb, uint16_t mbi, uint16_t flg, bool fmt1);
>  bool css_disable_mb(int schid);
>  
> +struct measurement_block_format0 {
> +	uint16_t ssch_rsch_count;
> +	uint16_t sample_count;
> +	uint32_t device_connect_time;
> +	uint32_t function_pending_time;
> +	uint32_t device_disconnect_time;
> +	uint32_t cu_queuing_time;
> +	uint32_t device_active_only_time;
> +	uint32_t device_busy_time;
> +	uint32_t initial_cmd_resp_time;
> +};
> +
>  #endif
> diff --git a/s390x/css.c b/s390x/css.c
> index e8f96f3..3915ed3 100644
> --- a/s390x/css.c
> +++ b/s390x/css.c
> @@ -184,6 +184,71 @@ static void test_schm(void)
>  	report_prefix_pop();
>  }
>  
> +#define SCHM_UPDATE_CNT 10
> +static bool start_measuring(uint64_t mbo, uint16_t mbi, bool fmt1)
> +{
> +	int i;
> +
> +	if (!css_enable_mb(test_device_sid, mbo, mbi, PMCW_MBUE, fmt1)) {
> +		report(0, "Enabling measurement_block_format");
> +		return false;
> +	}
> +
> +	for (i = 0; i < SCHM_UPDATE_CNT; i++) {
> +		if (!do_test_sense()) {
> +			report(0, "Error during sense");
> +			return false;
Are these hard fails, i.e. would it make sense to stop testing if this
or the css_enable_mb() above fails?

> +		}
> +	}
> +
> +	return true;
> +}
> +
> +/*
> + * test_schm_fmt0:
> + * With measurement block format 0 a memory space is shared
> + * by all subchannels, each subchannel can provide an index
> + * for the measurement block facility to store the measurements.
> + */
> +static void test_schm_fmt0(void)
> +{
> +	struct measurement_block_format0 *mb0;
> +	int shared_mb_size = 2 * sizeof(struct measurement_block_format0);
> +
> +	/* Allocate zeroed Measurement block */
> +	mb0 = alloc_io_mem(shared_mb_size, 0);
> +	if (!mb0) {
> +		report_abort("measurement_block_format0 allocation failed");
> +		return;
> +	}
> +
> +	schm(NULL, 0); /* Stop any previous measurement */
> +	schm(mb0, SCHM_MBU);
> +
> +	/* Expect success */
> +	report_prefix_push("Valid MB address and index 0");
> +	report(start_measuring(0, 0, false) &&
> +	       mb0->ssch_rsch_count == SCHM_UPDATE_CNT,
> +	       "SSCH measured %d", mb0->ssch_rsch_count);
> +	report_prefix_pop();
> +
> +	/* Clear the measurement block for the next test */
> +	memset(mb0, 0, shared_mb_size);
> +
> +	/* Expect success */
> +	report_prefix_push("Valid MB address and index 1");
> +	report(start_measuring(0, 1, false) &&
> +	       mb0[1].ssch_rsch_count == SCHM_UPDATE_CNT,
> +	       "SSCH measured %d", mb0[1].ssch_rsch_count);
> +	report_prefix_pop();
> +
> +	/* Stop the measurement */
> +	css_disable_mb(test_device_sid);
> +	schm(NULL, 0);
> +
> +	free_io_mem(mb0, shared_mb_size);
> +}
> +
>  static struct {
>  	const char *name;
>  	void (*func)(void);
> @@ -194,6 +259,7 @@ static struct {
>  	{ "enable (msch)", test_enable },
>  	{ "sense (ssch/tsch)", test_sense },
>  	{ "measurement block (schm)", test_schm },
> +	{ "measurement block format0", test_schm_fmt0 },
>  	{ NULL, NULL }
>  };
>  
>