Re: [kvm-unit-tests PATCH v2 5/8] s390x: lib: css: add SCSW ctrl expectations to check I/O completion

[Cornelia Huck <cohuck@redhat.com>]

On Thu, 25 Mar 2021 10:39:04 +0100
Pierre Morel <pmorel@linux.ibm.com> wrote:

> When checking for an I/O completion may need to check the cause of
> the interrupt depending on the test case.

"When we check for the completion of an I/O, we may need to check..." ?

> 
> Let's provide the tests the possibility to check if the last
> valid IRQ received is for the function expected after executing

"Let's make it possible for the tests to check whether the last valid
IRB received indicates the expected functions..." ?

> an instruction or sequence of instructions and if all ctrl flags
> of the SCSW are set as expected.
> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> ---
>  lib/s390x/css.h     |  4 ++--
>  lib/s390x/css_lib.c | 21 ++++++++++++++++-----
>  s390x/css.c         |  4 ++--
>  3 files changed, 20 insertions(+), 9 deletions(-)
> 

(...)

> diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
> index 1e5c409..55e70e6 100644
> --- a/lib/s390x/css_lib.c
> +++ b/lib/s390x/css_lib.c
> @@ -488,21 +488,25 @@ struct ccw1 *ccw_alloc(int code, void *data, int count, unsigned char flags)
>  
>  /* wait_and_check_io_completion:
>   * @schid: the subchannel ID
> + * @ctrl : expected SCSW control flags
>   */
> -int wait_and_check_io_completion(int schid)
> +int wait_and_check_io_completion(int schid, uint32_t ctrl)
>  {
>  	wait_for_interrupt(PSW_MASK_IO);
> -	return check_io_completion(schid);
> +	return check_io_completion(schid, ctrl);
>  }
>  
>  /* check_io_completion:
>   * @schid: the subchannel ID
> + * @ctrl : expected SCSW control flags
>   *
> - * Makes the most common check to validate a successful I/O
> - * completion.
> + * If the ctrl parameter is not null check the IRB SCSW ctrl
> + * against the ctrl parameter.
> + * Otherwise, makes the most common check to validate a successful
> + * I/O completion.

What about:

"Perform some standard checks to validate a successful I/O completion.
If the ctrl parameter is not zero, additionally verify that the
specified bits are indicated in the IRB SCSW ctrl flags."

>   * Only report failures.
>   */
> -int check_io_completion(int schid)
> +int check_io_completion(int schid, uint32_t ctrl)
>  {
>  	int ret = 0;
>  

With Thomas' suggested change,

Reviewed-by: Cornelia Huck <cohuck@redhat.com>