[igt-dev] [PATCH igt] tests/kms_frontbuffer_tracking: increase FBC wait timeout to 5s

[Paulo Zanoni]

From: "Lofstedt, Marta" <marta.lofstedt at intel.com>

This is a partial revert of:
64590c7b768dc8d8dd962f812d5ff5a39e7e8b54 ("kms_frontbuffer_tracking:
reduce the FBC wait timeout to 2s")

The subtests: igt at kms_frontbuffer_tracking@fbc-*draw* have
non-consistent results, pending between fail and pass. The fails are
always due to "FBC disabled".  With this increase in timeout the
flip-flop behavior is no longer reproducible.

We did not bisect why exactly this change is now required, since the
retire handler should happen about once per second and only be delayed
if user space is "hostile". Anyway, bumping from 2s to 5s really
reduces the chance that a skipped retirement cycle would affect the
results of the test. In case this still proves to be an issue we may
want to call igt_drop_caches_set(device, DROP_RETIRE), but then we'll
probably need a test that exercises the case where we don't use this
ioctl. For more information, see the discussion of this patch on the
mailing list (Aug/Sep 2017 on intel-gfx). For now let's merge this in
the hope that CI will have less failures.

v2 (from Paulo): update commit message and rebase.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101623
Signed-off-by: Marta Lofstedt <marta.lofstedt at intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
 tests/kms_frontbuffer_tracking.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/kms_frontbuffer_tracking.c b/tests/kms_frontbuffer_tracking.c
index 619186a5..64a80b6d 100644
--- a/tests/kms_frontbuffer_tracking.c
+++ b/tests/kms_frontbuffer_tracking.c
@@ -935,7 +935,7 @@ static bool fbc_is_compressing(void)
 
 static bool fbc_wait_for_compression(void)
 {
-	return igt_wait(fbc_is_compressing(), 2000, 1);
+	return igt_wait(fbc_is_compressing(), 5000, 1);
 }
 
 static bool fbc_not_enough_stolen(void)
@@ -958,7 +958,7 @@ static bool fbc_wait_until_enabled(void)
 {
 	last_fbc_buf[0] = '\0';
 
-	return igt_wait(fbc_is_enabled(IGT_LOG_DEBUG), 2000, 1);
+	return igt_wait(fbc_is_enabled(IGT_LOG_DEBUG), 5000, 1);
 }
 
 static bool psr_wait_until_enabled(void)
-- 
2.14.3