* [Intel-gfx] [PATCH] drm/i915: Drop i915_request.lock serialisation around await_start
@ 2020-07-17 9:32 Chris Wilson
2020-07-17 9:39 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for " Patchwork
2020-07-17 10:01 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
0 siblings, 2 replies; 3+ messages in thread
From: Chris Wilson @ 2020-07-17 9:32 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
Originally, we used the signal->lock as a means of following the
previous link in its timeline and peeking at the previous fence.
However, we have replaced the explicit serialisation with a series of
very careful probes that anticipate the links being deleted and the
fences recycled before we are able to acquire a strong reference to it.
We do not need the signal->lock crutch anymore, nor want the contention.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
---
drivers/gpu/drm/i915/i915_request.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index a7a3d457a837..1368c20a6514 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -977,9 +977,16 @@ i915_request_await_start(struct i915_request *rq, struct i915_request *signal)
if (i915_request_started(signal))
return 0;
+ /*
+ * The caller holds a reference on @signal, but we do not serialise
+ * against it being retired and removed from the lists.
+ *
+ * We do not hold a reference to the request before @signal, and
+ * so must be very careful to ensure that it is not _recycled_ as
+ * we follow the link backwards.
+ */
fence = NULL;
rcu_read_lock();
- spin_lock_irq(&signal->lock);
do {
struct list_head *pos = READ_ONCE(signal->link.prev);
struct i915_request *prev;
@@ -1010,7 +1017,6 @@ i915_request_await_start(struct i915_request *rq, struct i915_request *signal)
fence = &prev->fence;
} while (0);
- spin_unlock_irq(&signal->lock);
rcu_read_unlock();
if (!fence)
return 0;
--
2.20.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [Intel-gfx] ✗ Fi.CI.SPARSE: warning for drm/i915: Drop i915_request.lock serialisation around await_start
2020-07-17 9:32 [Intel-gfx] [PATCH] drm/i915: Drop i915_request.lock serialisation around await_start Chris Wilson
@ 2020-07-17 9:39 ` Patchwork
2020-07-17 10:01 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
1 sibling, 0 replies; 3+ messages in thread
From: Patchwork @ 2020-07-17 9:39 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
== Series Details ==
Series: drm/i915: Drop i915_request.lock serialisation around await_start
URL : https://patchwork.freedesktop.org/series/79588/
State : warning
== Summary ==
$ dim sparse --fast origin/drm-tip
Sparse version: v0.6.0
Fast mode used, each commit won't be checked separately.
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Intel-gfx] ✗ Fi.CI.BAT: failure for drm/i915: Drop i915_request.lock serialisation around await_start
2020-07-17 9:32 [Intel-gfx] [PATCH] drm/i915: Drop i915_request.lock serialisation around await_start Chris Wilson
2020-07-17 9:39 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for " Patchwork
@ 2020-07-17 10:01 ` Patchwork
1 sibling, 0 replies; 3+ messages in thread
From: Patchwork @ 2020-07-17 10:01 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
[-- Attachment #1.1: Type: text/plain, Size: 6172 bytes --]
== Series Details ==
Series: drm/i915: Drop i915_request.lock serialisation around await_start
URL : https://patchwork.freedesktop.org/series/79588/
State : failure
== Summary ==
CI Bug Log - changes from CI_DRM_8760 -> Patchwork_18200
====================================================
Summary
-------
**FAILURE**
Serious unknown changes coming with Patchwork_18200 absolutely need to be
verified manually.
If you think the reported changes have nothing to do with the changes
introduced in Patchwork_18200, 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_18200/index.html
Possible new issues
-------------------
Here are the unknown changes that may have been introduced in Patchwork_18200:
### IGT changes ###
#### Possible regressions ####
* igt@kms_chamelium@hdmi-crc-fast:
- fi-kbl-7500u: [PASS][1] -> [FAIL][2]
[1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-kbl-7500u/igt@kms_chamelium@hdmi-crc-fast.html
[2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-kbl-7500u/igt@kms_chamelium@hdmi-crc-fast.html
Known issues
------------
Here are the changes found in Patchwork_18200 that come from known issues:
### IGT changes ###
#### Issues hit ####
* igt@gem_exec_suspend@basic-s3:
- fi-tgl-u2: [PASS][3] -> [FAIL][4] ([i915#1888])
[3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-tgl-u2/igt@gem_exec_suspend@basic-s3.html
[4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-tgl-u2/igt@gem_exec_suspend@basic-s3.html
* igt@gem_flink_basic@bad-open:
- fi-tgl-y: [PASS][5] -> [DMESG-WARN][6] ([i915#402])
[5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-tgl-y/igt@gem_flink_basic@bad-open.html
[6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-tgl-y/igt@gem_flink_basic@bad-open.html
* igt@i915_module_load@reload:
- fi-tgl-u2: [PASS][7] -> [DMESG-WARN][8] ([i915#402])
[7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-tgl-u2/igt@i915_module_load@reload.html
[8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-tgl-u2/igt@i915_module_load@reload.html
* igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic:
- fi-icl-u2: [PASS][9] -> [DMESG-WARN][10] ([i915#1982])
[9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-icl-u2/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic.html
[10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-icl-u2/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic.html
#### Possible fixes ####
* igt@kms_flip@basic-flip-vs-dpms@a-dsi1:
- {fi-tgl-dsi}: [DMESG-WARN][11] ([i915#1982]) -> [PASS][12]
[11]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-tgl-dsi/igt@kms_flip@basic-flip-vs-dpms@a-dsi1.html
[12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-tgl-dsi/igt@kms_flip@basic-flip-vs-dpms@a-dsi1.html
* igt@kms_flip@basic-flip-vs-wf_vblank@b-edp1:
- fi-icl-u2: [DMESG-WARN][13] ([i915#1982]) -> [PASS][14]
[13]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-icl-u2/igt@kms_flip@basic-flip-vs-wf_vblank@b-edp1.html
[14]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-icl-u2/igt@kms_flip@basic-flip-vs-wf_vblank@b-edp1.html
* igt@vgem_basic@setversion:
- fi-tgl-y: [DMESG-WARN][15] ([i915#402]) -> [PASS][16] +1 similar issue
[15]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-tgl-y/igt@vgem_basic@setversion.html
[16]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-tgl-y/igt@vgem_basic@setversion.html
#### Warnings ####
* igt@gem_exec_suspend@basic-s0:
- fi-kbl-x1275: [DMESG-WARN][17] ([i915#62] / [i915#92] / [i915#95]) -> [DMESG-WARN][18] ([i915#62] / [i915#92]) +1 similar issue
[17]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-kbl-x1275/igt@gem_exec_suspend@basic-s0.html
[18]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-kbl-x1275/igt@gem_exec_suspend@basic-s0.html
* igt@kms_cursor_legacy@basic-busy-flip-before-cursor-legacy:
- fi-kbl-x1275: [DMESG-WARN][19] ([i915#62] / [i915#92]) -> [DMESG-WARN][20] ([i915#62] / [i915#92] / [i915#95]) +1 similar issue
[19]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8760/fi-kbl-x1275/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-legacy.html
[20]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/fi-kbl-x1275/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-legacy.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
[i915#1814]: https://gitlab.freedesktop.org/drm/intel/issues/1814
[i915#1888]: https://gitlab.freedesktop.org/drm/intel/issues/1888
[i915#1982]: https://gitlab.freedesktop.org/drm/intel/issues/1982
[i915#402]: https://gitlab.freedesktop.org/drm/intel/issues/402
[i915#62]: https://gitlab.freedesktop.org/drm/intel/issues/62
[i915#92]: https://gitlab.freedesktop.org/drm/intel/issues/92
[i915#95]: https://gitlab.freedesktop.org/drm/intel/issues/95
Participating hosts (45 -> 40)
------------------------------
Missing (5): fi-ilk-m540 fi-hsw-4200u fi-byt-squawks fi-bsw-cyan fi-byt-clapper
Build changes
-------------
* Linux: CI_DRM_8760 -> Patchwork_18200
CI-20190529: 20190529
CI_DRM_8760: 6cd3f0d5b81362d933c87318fa0bc3badd9ab92d @ git://anongit.freedesktop.org/gfx-ci/linux
IGT_5738: bc8b56fe177af34fbde7b96f1f66614a0014c6ef @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools
Patchwork_18200: 63b969105b28cd6cbe98d80d7192b1a0179742e1 @ git://anongit.freedesktop.org/gfx-ci/linux
== Linux commits ==
63b969105b28 drm/i915: Drop i915_request.lock serialisation around await_start
== Logs ==
For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18200/index.html
[-- Attachment #1.2: Type: text/html, Size: 7625 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
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-07-17 10:01 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-17 9:32 [Intel-gfx] [PATCH] drm/i915: Drop i915_request.lock serialisation around await_start Chris Wilson
2020-07-17 9:39 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for " Patchwork
2020-07-17 10:01 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.