[Intel-gfx] [PATCH] drm/i915/selftest: Synchronise with the GPU timestamp

[Intel-gfx] [PATCH] drm/i915/selftest: Synchronise with the GPU timestamp

[Chris Wilson]

Wait for the GPU to wake up from the semaphore before measuring the
time, so that we coordinate the sampling on both the CPU and GPU for
more accurate comparisons.

Reported-by: Bruce Chang <yu.bruce.chang@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: CQ Tang <cq.tang@intel.com>
---
 drivers/gpu/drm/i915/gt/selftest_engine_pm.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/selftest_engine_pm.c b/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
index 3ce8cb3329f3..007a7c790778 100644
--- a/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
+++ b/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
@@ -111,8 +111,10 @@ static int __measure_timestamps(struct intel_context *ce,
 
 	/* Run the request for a 100us, sampling timestamps before/after */
 	preempt_disable();
-	*dt = local_clock();
 	write_semaphore(&sema[2], 0);
+	while (READ_ONCE(sema[1]) == 0) /* wait for the gpu to catch up */
+		cpu_relax();
+	*dt = local_clock();
 	udelay(100);
 	*dt = local_clock() - *dt;
 	write_semaphore(&sema[2], 1);
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [Intel-gfx] [PATCH] drm/i915/selftest: Synchronise with the GPU timestamp

[Chang, Yu bruce]

[-- Attachment #1.1: Type: text/plain, Size: 1324 bytes --]

> Wait for the GPU to wake up from the semaphore before measuring the
>time, so that we coordinate the sampling on both the CPU and GPU for
> more accurate comparisons.
>
>Reported-by: Bruce Chang <yu.bruce.chang@intel.com>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: CQ Tang <cq.tang@intel.com>
> ---
>  drivers/gpu/drm/i915/gt/selftest_engine_pm.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/selftest_engine_pm.c b/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
>index 3ce8cb3329f3..007a7c790778 100644
> --- a/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
> +++ b/drivers/gpu/drm/i915/gt/selftest_engine_pm.c
> @@ -111,8 +111,10 @@ static int __measure_timestamps(struct intel_context *ce,
>
>         /* Run the request for a 100us, sampling timestamps before/after */
>          preempt_disable();
> -       *dt = local_clock();
>         write_semaphore(&sema[2], 0);
> +       while (READ_ONCE(sema[1]) == 0) /* wait for the gpu to catch up */
> +               cpu_relax();
> +       *dt = local_clock();
>          udelay(100);
>         *dt = local_clock() - *dt;
>          write_semaphore(&sema[2], 1);
> --
>2.20.1
>

This trick should work!
Thanks!

Reviewed-by: Bruce Chang <yu.bruce.chang@intel.com>


[-- Attachment #1.2: Type: text/html, Size: 2928 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[Intel-gfx] ✗ Fi.CI.BAT: failure for drm/i915/selftest: Synchronise with the GPU timestamp

[Patchwork]

[-- Attachment #1.1: Type: text/plain, Size: 6384 bytes --]

== Series Details ==

Series: drm/i915/selftest: Synchronise with the GPU timestamp
URL   : https://patchwork.freedesktop.org/series/86731/
State : failure

== Summary ==

CI Bug Log - changes from CI_DRM_9735 -> Patchwork_19597
====================================================

Summary
-------

  **FAILURE**

  Serious unknown changes coming with Patchwork_19597 absolutely need to be
  verified manually.
  
  If you think the reported changes have nothing to do with the changes
  introduced in Patchwork_19597, please notify your bug team to allow them
  to document this new failure mode, which will reduce false positives in CI.

  External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/index.html

Possible new issues
-------------------

  Here are the unknown changes that may have been introduced in Patchwork_19597:

### IGT changes ###

#### Possible regressions ####

  * igt@i915_selftest@live@gt_engines:
    - fi-bsw-nick:        [PASS][1] -> [FAIL][2]
   [1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-bsw-nick/igt@i915_selftest@live@gt_engines.html
   [2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-bsw-nick/igt@i915_selftest@live@gt_engines.html

  * igt@i915_selftest@live@gt_lrc:
    - fi-bsw-n3050:       [PASS][3] -> [INCOMPLETE][4]
   [3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-bsw-n3050/igt@i915_selftest@live@gt_lrc.html
   [4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-bsw-n3050/igt@i915_selftest@live@gt_lrc.html

  
Known issues
------------

  Here are the changes found in Patchwork_19597 that come from known issues:

### IGT changes ###

#### Issues hit ####

  * igt@debugfs_test@read_all_entries:
    - fi-tgl-y:           [PASS][5] -> [DMESG-WARN][6] ([i915#402]) +2 similar issues
   [5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-tgl-y/igt@debugfs_test@read_all_entries.html
   [6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-tgl-y/igt@debugfs_test@read_all_entries.html

  * igt@gem_exec_suspend@basic-s3:
    - fi-tgl-u2:          [PASS][7] -> [FAIL][8] ([i915#1888])
   [7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-tgl-u2/igt@gem_exec_suspend@basic-s3.html
   [8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-tgl-u2/igt@gem_exec_suspend@basic-s3.html

  * igt@gem_huc_copy@huc-copy:
    - fi-byt-j1900:       NOTRUN -> [SKIP][9] ([fdo#109271]) +9 similar issues
   [9]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-byt-j1900/igt@gem_huc_copy@huc-copy.html

  * igt@i915_pm_rpm@module-reload:
    - fi-byt-j1900:       NOTRUN -> [INCOMPLETE][10] ([i915#142] / [i915#2405])
   [10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-byt-j1900/igt@i915_pm_rpm@module-reload.html

  * igt@kms_chamelium@hdmi-crc-fast:
    - fi-byt-j1900:       NOTRUN -> [SKIP][11] ([fdo#109271] / [fdo#111827]) +8 similar issues
   [11]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-byt-j1900/igt@kms_chamelium@hdmi-crc-fast.html

  * igt@runner@aborted:
    - fi-kbl-guc:         NOTRUN -> [FAIL][12] ([i915#2426])
   [12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-kbl-guc/igt@runner@aborted.html
    - fi-byt-j1900:       NOTRUN -> [FAIL][13] ([i915#1814] / [i915#2505])
   [13]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-byt-j1900/igt@runner@aborted.html
    - fi-bsw-n3050:       NOTRUN -> [FAIL][14] ([i915#1436])
   [14]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-bsw-n3050/igt@runner@aborted.html

  
#### Possible fixes ####

  * igt@fbdev@write:
    - fi-tgl-y:           [DMESG-WARN][15] ([i915#402]) -> [PASS][16] +2 similar issues
   [15]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-tgl-y/igt@fbdev@write.html
   [16]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-tgl-y/igt@fbdev@write.html

  * igt@i915_selftest@live@gt_heartbeat:
    - fi-cfl-8700k:       [DMESG-FAIL][17] ([i915#2291] / [i915#541]) -> [PASS][18]
   [17]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-cfl-8700k/igt@i915_selftest@live@gt_heartbeat.html
   [18]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-cfl-8700k/igt@i915_selftest@live@gt_heartbeat.html

  * igt@i915_selftest@live@late_gt_pm:
    - {fi-ehl-1}:         [DMESG-FAIL][19] -> [PASS][20]
   [19]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_9735/fi-ehl-1/igt@i915_selftest@live@late_gt_pm.html
   [20]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/fi-ehl-1/igt@i915_selftest@live@late_gt_pm.html

  
  {name}: This element is suppressed. This means it is ignored when computing
          the status of the difference (SUCCESS, WARNING, or FAILURE).

  [fdo#109271]: https://bugs.freedesktop.org/show_bug.cgi?id=109271
  [fdo#109315]: https://bugs.freedesktop.org/show_bug.cgi?id=109315
  [fdo#111827]: https://bugs.freedesktop.org/show_bug.cgi?id=111827
  [i915#142]: https://gitlab.freedesktop.org/drm/intel/issues/142
  [i915#1436]: https://gitlab.freedesktop.org/drm/intel/issues/1436
  [i915#1814]: https://gitlab.freedesktop.org/drm/intel/issues/1814
  [i915#1888]: https://gitlab.freedesktop.org/drm/intel/issues/1888
  [i915#2291]: https://gitlab.freedesktop.org/drm/intel/issues/2291
  [i915#2405]: https://gitlab.freedesktop.org/drm/intel/issues/2405
  [i915#2426]: https://gitlab.freedesktop.org/drm/intel/issues/2426
  [i915#2505]: https://gitlab.freedesktop.org/drm/intel/issues/2505
  [i915#402]: https://gitlab.freedesktop.org/drm/intel/issues/402
  [i915#541]: https://gitlab.freedesktop.org/drm/intel/issues/541


Participating hosts (42 -> 39)
------------------------------

  Additional (1): fi-byt-j1900 
  Missing    (4): fi-jsl-1 fi-ilk-m540 fi-bsw-cyan fi-bdw-samus 


Build changes
-------------

  * Linux: CI_DRM_9735 -> Patchwork_19597

  CI-20190529: 20190529
  CI_DRM_9735: 186ea69ad1d026d004fbd64457fb576ab86556eb @ git://anongit.freedesktop.org/gfx-ci/linux
  IGT_5991: a2d9c45fca85918ecf47761205555aade64b9220 @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools
  Patchwork_19597: cdf44ae51736690dfc2e8a60927d89ce3e71709b @ git://anongit.freedesktop.org/gfx-ci/linux


== Linux commits ==

cdf44ae51736 drm/i915/selftest: Synchronise with the GPU timestamp

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_19597/index.html

[-- Attachment #1.2: Type: text/html, Size: 7388 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx