[igt-dev] [PATCH i-g-t] i915/gem_mmap_gtt: Replace forked-mmaped tests with a lighter variant

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> Introduce a new 2-process fork test that is bound to a single cpu to
> exercise contention during pagefaults. This is a much lighter variant of
> the all-cpus test intended to be viable even on the legendary frozen
> lakes of molasses.
>
> References: https://bugs.freedesktop.org/show_bug.cgi?id=110882
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Cc: Martin Peres <martin.peres at linux.intel.com>
> ---
>  tests/i915/gem_mmap_gtt.c    | 36 +++++++++++++++++++++++++-----------
>  tests/intel-ci/blacklist.txt |  2 +-
>  2 files changed, 26 insertions(+), 12 deletions(-)
>
> diff --git a/tests/i915/gem_mmap_gtt.c b/tests/i915/gem_mmap_gtt.c
> index ac439cdf8..0428a1372 100644
> --- a/tests/i915/gem_mmap_gtt.c
> +++ b/tests/i915/gem_mmap_gtt.c
> @@ -792,9 +792,6 @@ test_huge_copy(int fd, int huge, int tiling_a, int tiling_b, int ncpus)
>  	uint64_t huge_object_size, i;
>  	unsigned mode = CHECK_RAM;
>  
> -	igt_fail_on_f(intel_gen(devid) >= 11 && ncpus > 1,
> -		      "Please adjust your expectations, https://bugs.freedesktop.org/show_bug.cgi?id=110882\n");
> -
>  	switch (huge) {
>  	case -2:
>  		huge_object_size = gem_mappable_aperture_size() / 4;
> @@ -1138,17 +1135,34 @@ igt_main
>  			for (const struct copy_mode *m = copy_modes; m->suffix; m++) {
>  				igt_subtest_f("%s-copy%s", s->prefix, m->suffix)
>  					test_huge_copy(fd,
> -							s->size,
> -							m->tiling_x,
> -							m->tiling_y,
> -							1);
> +						       s->size,
> +						       m->tiling_x,
> +						       m->tiling_y,
> +						       1);
> +
> +				igt_subtest_f("cpuset-%s-copy%s", s->prefix, m->suffix) {
> +					cpu_set_t cpu, old;
> +
> +					sched_getaffinity(0, sizeof(old), &old);
> +
> +					CPU_ZERO(&cpu);
> +					CPU_SET(0, &cpu);
> +					igt_assert(sched_setaffinity(0, sizeof(cpu), &cpu) == 0);
> +					test_huge_copy(fd,
> +						       s->size,
> +						       m->tiling_x,
> +						       m->tiling_y,
> +						       2);
> +
> +					igt_assert(sched_setaffinity(0, sizeof(old), &old) == 0);
> +				}
>  
>  				igt_subtest_f("forked-%s-copy%s", s->prefix, m->suffix)
>  					test_huge_copy(fd,
> -							s->size,
> -							m->tiling_x,
> -							m->tiling_y,
> -							ncpus);
> +						       s->size,
> +						       m->tiling_x,
> +						       m->tiling_y,
> +						       ncpus);
>  			}
>  	}
>  
> diff --git a/tests/intel-ci/blacklist.txt b/tests/intel-ci/blacklist.txt
> index 8e3dafa98..5fa91105f 100644
> --- a/tests/intel-ci/blacklist.txt
> +++ b/tests/intel-ci/blacklist.txt
> @@ -47,7 +47,7 @@ igt at gem_gtt_hog(@.*)?
>  igt at gem_gtt_speed(@.*)?
>  igt at gem_hangcheck_forcewake(@.*)?
>  igt at gem_lut_handle(@.*)?
> -igt at gem_mmap_gtt@.*(huge|swap|clflush).*
> +igt at gem_mmap_gtt@.*(huge|swap|clflush|forked).*

Dunno if this is enough for bat to pick it up. Regardless,
patch does what it says, using 2 threads on single cpu.

It should fly, even with maps of molasses.

Reviewed-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>

>  igt at gem_mmap@.*(swap|huge).*
>  igt at gem_mocs_settings@.*(suspend|hibernate).*
>  igt at gem_pin(@.*)?
> -- 
> 2.23.0