Hi Shaopeng,
I understand there is a typo in the code you are modifying but I do not think
that justifies the same typo in the subject: shemata -> schemata
On 10/4/2022 6:39 PM, Shaopeng Tan wrote:
> There is a comment "Set up shemata with 100% allocation on the first run"
> in function mbm_setup(), but there is an increment bug and the condition
> "num_of_runs == 0" will never be met and write_schemata() will never be
> called to set schemata to 100%. This is currently fine because
> resctl_val_parm->num_resctrlfs is always 1 and umount/mount will be run
resctl_val_parm -> resctrl_val_param
num_resctrlfs -> mum_resctrlfs
> in each test to set the schemata to 100%.
>
> To make mbm_setup() future code-change proof, fix to call
You could be more specific by indicating that this change will
support the usage when the test does not unmount/remount resctrl before
the test.
> write-schemata() properly when the function is called for the first time.
write-schemata() -> write_schemata()
>
> Also, remove static local variable 'num_of_runs' because this is not
> needed as there is resctl_val_param->num_of_runs which should be used
resctl_val_param -> resctrl_val_param
> instead like in cat_setup().
With the move to using a member from the struct I think it would make the
code easier to understand if num_of_runs is explicitly initialized. That is
indeed the norm when looking at the other call sites.
>
> Signed-off-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
> ---
> tools/testing/selftests/resctrl/mbm_test.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
> index 8392e5c55ed0..4a54be314402 100644
> --- a/tools/testing/selftests/resctrl/mbm_test.c
> +++ b/tools/testing/selftests/resctrl/mbm_test.c
> @@ -89,12 +89,11 @@ static int check_results(int span)
> static int mbm_setup(int num, ...)
> {
> struct resctrl_val_param *p;
p is defined here ...
> - static int num_of_runs;
> va_list param;
> int ret = 0;
>
> /* Run NUM_OF_RUNS times */
> - if (num_of_runs++ >= NUM_OF_RUNS)
> + if (p->num_of_runs >= NUM_OF_RUNS)
p is used here _before_ it is initialized in the code that follows.
> return -1;
>
> va_start(param, num);
> @@ -102,9 +101,10 @@ static int mbm_setup(int num, ...)
> va_end(param);
>
> /* Set up shemata with 100% allocation on the first run. */
> - if (num_of_runs == 0)
> + if (p->num_of_runs == 0)
> ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
> p->resctrl_val);
> + p->num_of_runs++;
>
> return ret;
> }
Reinette
