Re: [igt-dev] [PATCH i-g-t 7/9] tests/i915_pm_rpm: use device coherent mapping instead of mmap_gtt

Ramalingam C
2020-02-07T12:59:15Z

On 2020-02-04 at 16:16:38 -0800, Dixit, Ashutosh wrote:
> On Fri, 31 Jan 2020 09:31:07 -0800, Ramalingam C wrote:
> >
> > Since on new discrete GPUs we dont have the mappable aperture, if that
> > is acceptable for the test purpose, we should use GEM_MMAP_OFFSET.
> > Hence using gem_mmap_device_coherent() which wraps the mmap options in
> > the order of gem_mmap_offset / gem_mmap / mmap_gtt
> >
> > Incase of fencing/gtt related tests, we mandate the existance of the
> > mmap_gtt.
> >
> > Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
> > ---
> > tests/i915/i915_pm_rpm.c | 24 +++++++++++++++---------
> > 1 file changed, 15 insertions(+), 9 deletions(-)
> >
> > diff --git a/tests/i915/i915_pm_rpm.c b/tests/i915/i915_pm_rpm.c
> > index f5f813c3d952..9524d7d3a4dd 100644
> > --- a/tests/i915/i915_pm_rpm.c
> > +++ b/tests/i915/i915_pm_rpm.c
> > @@ -1392,8 +1392,8 @@ static void gem_evict_pwrite_subtest(void)
> >
> > for (n = 0; n < num_trash_bos; n++) {
> > trash_bos[n].handle = gem_create(drm_fd, 1024*1024);
> > - trash_bos[n].ptr = gem_mmap__gtt(drm_fd, trash_bos[n].handle,
> > - 1024*1024, PROT_WRITE);
> > + trash_bos[n].ptr = gem_mmap__device_coherent(drm_fd, trash_bos[n].handle,
> > + 0, 1024*1024, PROT_WRITE);
> > *trash_bos[n].ptr = 0;
> > }
>
> What does gem_mappable_aperture_size() just above return when we don't have
> a mappable aperture? Maybe this also needs to be skipped instead?
Actually the tests are skipped because igt_pm_dmc_loaded(debugfs) is
failing at setup_environment. So all gtt related cases are hidden. But
yes this has to be skipped as aperture size is used or rewritten for
display. For now I am choosing the skipping path.
>
> > @@ -1535,7 +1535,7 @@ static void fill_igt_fb(struct igt_fb *fb, uint32_t color)
> > int i;
> > uint32_t *ptr;
> >
> > - ptr = gem_mmap__gtt(drm_fd, fb->gem_handle, fb->size, PROT_WRITE);
> > + ptr = gem_mmap__device_coherent(drm_fd, fb->gem_handle, 0, fb->size, PROT_WRITE);
> > for (i = 0; i < fb->size/sizeof(uint32_t); i++)
> > ptr[i] = color;
> > igt_assert(munmap(ptr, fb->size) == 0);
>
> Even though fill_igt_fb() is called with tiling set, I think it is still ok
> to do this since all we are doing is filling a solid color for which tiling
> is immaterial.
>
> > @@ -1827,8 +1827,8 @@ static void pm_test_tiling(void)
> > for (j = 0, k = 1 << off_bit;
> > k <= gtt_obj_max_size; k <<= 1, j++) {
> > handles[j] = gem_create(drm_fd, k);
> > - gem_bufs[j] = gem_mmap__gtt(drm_fd, handles[j],
> > - k, PROT_WRITE);
> > + gem_bufs[j] = gem_mmap__device_coherent(drm_fd, handles[j],
> > + 0, k, PROT_WRITE);
> > memset(gem_bufs[j], 0x0, k);
> > }
>
> Maybe we should skip this instead because set/get tiling calls below will
> fail/assert?
Yes I will skip.
>
> > @@ -1872,7 +1872,7 @@ static void pm_test_caching(void)
> >
> > handle = gem_create(drm_fd, gtt_obj_max_size);
> > default_cache_level = gem_get_caching(drm_fd, handle);
> > - gem_buf = gem_mmap__gtt(drm_fd, handle, gtt_obj_max_size, PROT_WRITE);
> > + gem_buf = gem_mmap__device_coherent(drm_fd, handle, 0, gtt_obj_max_size, PROT_WRITE);
> >
> > for (i = 0; i < ARRAY_SIZE(cache_levels); i++) {
> > igt_assert(wait_for_suspended());
>
> Does the test work ok or assert with this change? Also I am not sure but
> from the comments it seems the purpose of the test is to really do with
> GGTT so it should be skipped when we don't have aperture?
since all tests are skipping, I am not sure about the functional impact.
True comments talk about GGTT mapping. Better skip as of now. I will do
the changes

Ram
>
> > @@ -2016,8 +2016,10 @@ igt_main_args("", long_options, help_str, opt_handler, NULL)
> > /* GEM */
> > igt_subtest("gem-mmap-cpu")
> > gem_mmap_subtest(false);
> > - igt_subtest("gem-mmap-gtt")
> > + igt_subtest("gem-mmap-gtt") {
> > + gem_require_mappable_ggtt(drm_fd);
> > gem_mmap_subtest(true);
> > + }
> > igt_subtest("gem-pread")
> > gem_pread_subtest();
> > igt_subtest("gem-execbuf")
> > @@ -2058,10 +2060,14 @@ igt_main_args("", long_options, help_str, opt_handler, NULL)
> > dpms_mode_unset_subtest(SCREEN_TYPE_LPSP);
> > igt_subtest("dpms-mode-unset-non-lpsp")
> > dpms_mode_unset_subtest(SCREEN_TYPE_NON_LPSP);
> > - igt_subtest("fences")
> > + igt_subtest("fences") {
> > + gem_require_mappable_ggtt(drm_fd);
> > fences_subtest(false);
> > - igt_subtest("fences-dpms")
> > + }
> > + igt_subtest("fences-dpms") {
> > + gem_require_mappable_ggtt(drm_fd);
> > fences_subtest(true);
> > + }
>
> These skips look ok to me.