On Wed, 16 Aug 2023, Reinette Chatre wrote: > On 8/16/2023 12:13 AM, Ilpo Järvinen wrote: > > On Tue, 15 Aug 2023, Reinette Chatre wrote: > >> On 8/15/2023 2:42 AM, Ilpo Järvinen wrote: > >>> On Mon, 14 Aug 2023, Reinette Chatre wrote: > >>>> > >>>> On 8/8/2023 2:16 AM, Ilpo Järvinen wrote: > > ... > >>>>> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h > >>>>> index bcd0d2060f81..ddb1e83a3a64 100644 > >>>>> --- a/tools/testing/selftests/resctrl/resctrl.h > >>>>> +++ b/tools/testing/selftests/resctrl/resctrl.h > >>>>> @@ -6,6 +6,7 @@ > >>>>> #include <math.h> > >>>>> #include <errno.h> > >>>>> #include <sched.h> > >>>>> +#include <stdint.h> > >>>>> #include <stdlib.h> > >>>>> #include <unistd.h> > >>>>> #include <string.h> > >>>>> @@ -38,7 +39,14 @@ > >>>>> > >>>>> #define END_OF_TESTS 1 > >>>>> > >>>>> +#define BENCHMARK_ARGS 64 > >>>>> + > >>>>> +/* Approximate %zu max length */ > >>>>> +#define SIZE_MAX_DECIMAL_SIZE (sizeof(SIZE_MAX) * 8 / 3 + 2) > >>>>> + > >>>>> +/* Define default span both as integer and string, these should match */ > >>>>> #define DEFAULT_SPAN (250 * MB) > >>>>> +#define DEFAULT_SPAN_STR "262144000" > >>>> > >>>> I think above hardcoding can be eliminated by using asprintf()? This > >>>> does allocate memory though so I would like to understand why one > >>>> goal is to not dynamically allocate memory. > >>> > >>> Because it's simpler on the _free() side_. If there's no allocation, no > >>> free() is needed. > >>> > >>> Only challenge that remains is the int -> string conversion for the > >>> default span which can be either done like in the patch or using some > >>> preprocessor trickery to convert the number to string. If you prefer the > >>> latter, I can change to that so it's not hardcoded both as int and string. > >>> > >> > >> This manual int->string sounds like the trickery to me and can be avoided > >> by just using asprintf(). I understand that no free() is needed when no > >> memory is allocated but it looks to me as though these allocations can > >> be symmetrical - allocate the memory before the tests are run and free it > >> after? > > > > It could be symmetrical but that means I'll be doing unnecessary alloc if > > -b is provided which I assume you're against given your comment on always > > creating copy of cmd in CMT test's case. > > I seemed to have lost track here ... could you please elaborate where the > unnecessary alloc will be? If there's what you call "symmetry", it implies the code always does alloc. However, the logic in main() is such that when -b is provided, no default benchmark command needs to be assigned, so no alloc for span is necessary. Thus, there either is unnecessary alloc with -b or _no symmetry_. But I've already converted to asprintf() so no need to continue this discussion. > > I think I'll use similar resolution to this as CMT test does, it has an > > extra variable which is NULL in when -b is provided so free() is no-op > > on that path. Then I can use asprintf(). > > > > Reinette > -- i.
