| Message ID | 1463139909-12826-1-git-send-email-gabriel.feceoru@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 13, 2016 at 02:45:09PM +0300, Gabriel Feceoru wrote: > basic-flip-vs-wf_vblank subtest sometimes fails asserting counted frames to > be aproximately equal with the estimated number. > > This is a false negative, one of the reasons being the precision lost when > truncating a fractional number. > > Fixed this by using floating point arithmetic. > > Cc: Jani Nikula <jani.nikula@intel.com> > Cc: Daniel Vetter <daniel.vetter@intel.com> > Signed-off-by: Gabriel Feceoru <gabriel.feceoru@intel.com> > --- > tests/kms_flip.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/tests/kms_flip.c b/tests/kms_flip.c > index eda2fcc..6ec97d0 100644 > --- a/tests/kms_flip.c > +++ b/tests/kms_flip.c > @@ -1182,13 +1182,13 @@ static void check_final_state(struct test_output *o, struct event_state *es, > /* Verify we drop no frames, but only if it's not a TV encoder, since > * those use some funny fake timings behind userspace's back. */ > if (o->flags & TEST_CHECK_TS && !analog_tv_connector(o)) { > - int expected; > + double expected; > int count = es->count; > > count *= o->seq_step; > - expected = elapsed / frame_time(o); int expected = count * frame_time(o); igt_assert_f(100 * expected >= elasped * 99 && 100 * count <= expected * 101, "dropped frames, expected %d, counted %d, encoder type %d\n", elapsed / frame_time(o), count, o->kencoder[0]->encoder_type); if I understood your concern correctly, as the only loss of precison there would be from calculating 'expected'. -Chris
On Fri, May 13, 2016 at 01:00:33PM +0100, Chris Wilson wrote: > On Fri, May 13, 2016 at 02:45:09PM +0300, Gabriel Feceoru wrote: > > basic-flip-vs-wf_vblank subtest sometimes fails asserting counted frames to > > be aproximately equal with the estimated number. > > > > This is a false negative, one of the reasons being the precision lost when > > truncating a fractional number. > > > > Fixed this by using floating point arithmetic. > > > > Cc: Jani Nikula <jani.nikula@intel.com> > > Cc: Daniel Vetter <daniel.vetter@intel.com> > > Signed-off-by: Gabriel Feceoru <gabriel.feceoru@intel.com> > > --- > > tests/kms_flip.c | 8 ++++---- > > 1 file changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/tests/kms_flip.c b/tests/kms_flip.c > > index eda2fcc..6ec97d0 100644 > > --- a/tests/kms_flip.c > > +++ b/tests/kms_flip.c > > @@ -1182,13 +1182,13 @@ static void check_final_state(struct test_output *o, struct event_state *es, > > /* Verify we drop no frames, but only if it's not a TV encoder, since > > * those use some funny fake timings behind userspace's back. */ > > if (o->flags & TEST_CHECK_TS && !analog_tv_connector(o)) { > > - int expected; > > + double expected; > > int count = es->count; > > > > count *= o->seq_step; > > - expected = elapsed / frame_time(o); > > int expected = count * frame_time(o); > igt_assert_f(100 * expected >= elasped * 99 && 100 * count <= expected * 101, igt_assert_f(100 * expected >= elasped * 99 && 100 * expected <= elasped * 101, -Chris
On 13.05.2016 15:00, Chris Wilson wrote: > On Fri, May 13, 2016 at 02:45:09PM +0300, Gabriel Feceoru wrote: >> basic-flip-vs-wf_vblank subtest sometimes fails asserting counted frames to >> be aproximately equal with the estimated number. >> >> This is a false negative, one of the reasons being the precision lost when >> truncating a fractional number. >> >> Fixed this by using floating point arithmetic. >> >> Cc: Jani Nikula <jani.nikula@intel.com> >> Cc: Daniel Vetter <daniel.vetter@intel.com> >> Signed-off-by: Gabriel Feceoru <gabriel.feceoru@intel.com> >> --- >> tests/kms_flip.c | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/tests/kms_flip.c b/tests/kms_flip.c >> index eda2fcc..6ec97d0 100644 >> --- a/tests/kms_flip.c >> +++ b/tests/kms_flip.c >> @@ -1182,13 +1182,13 @@ static void check_final_state(struct test_output *o, struct event_state *es, >> /* Verify we drop no frames, but only if it's not a TV encoder, since >> * those use some funny fake timings behind userspace's back. */ >> if (o->flags & TEST_CHECK_TS && !analog_tv_connector(o)) { >> - int expected; >> + double expected; >> int count = es->count; >> >> count *= o->seq_step; >> - expected = elapsed / frame_time(o); > > int expected = count * frame_time(o); > igt_assert_f(100 * expected >= elasped * 99 && 100 * count <= expected * 101, > "dropped frames, expected %d, counted %d, encoder type %d\n", > elapsed / frame_time(o), count, o->kencoder[0]->encoder_type); > > if I understood your concern correctly, as the only loss of precison > there would be from calculating 'expected'. That would also do it, but with care where to use the cast: int expected = (int)((double)count * frame_time(o)); vs int expected = count * (int)frame_time(o); Gabriel. > -Chris >
diff --git a/tests/kms_flip.c b/tests/kms_flip.c index eda2fcc..6ec97d0 100644 --- a/tests/kms_flip.c +++ b/tests/kms_flip.c @@ -1182,13 +1182,13 @@ static void check_final_state(struct test_output *o, struct event_state *es, /* Verify we drop no frames, but only if it's not a TV encoder, since * those use some funny fake timings behind userspace's back. */ if (o->flags & TEST_CHECK_TS && !analog_tv_connector(o)) { - int expected; + double expected; int count = es->count; count *= o->seq_step; - expected = elapsed / frame_time(o); - igt_assert_f(count >= expected * 99/100 && count <= expected * 101/100, - "dropped frames, expected %d, counted %d, encoder type %d\n", + expected = (double)elapsed / frame_time(o); + igt_assert_f(fabs((double)count - expected)/expected <= 0.01, + "dropped frames, expected %f, counted %d, encoder type %d\n", expected, count, o->kencoder[0]->encoder_type); } }
basic-flip-vs-wf_vblank subtest sometimes fails asserting counted frames to be aproximately equal with the estimated number. This is a false negative, one of the reasons being the precision lost when truncating a fractional number. Fixed this by using floating point arithmetic. Cc: Jani Nikula <jani.nikula@intel.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Gabriel Feceoru <gabriel.feceoru@intel.com> --- tests/kms_flip.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)