[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 799 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

Chris Wilson <chris@chris-wilson.co.uk> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|mesa-dev@lists.freedesktop. |dri-devel@lists.freedesktop
                   |org                         |.org
         QA Contact|mesa-dev@lists.freedesktop. |dri-devel@lists.freedesktop
                   |org                         |.org
          Component|Mesa core                   |Drivers/DRI/i915

--- Comment #2 from Chris Wilson <chris@chris-wilson.co.uk> ---
-EDEADLOCK = userspace tried to use more fence registers than the HW supports.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2385 bytes --]

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

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 1012 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #3 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
I am using intel i915 gen 3 with 16 fence registers.
When displaying the variable total_fences
at function drm_intel_gem_check_aperture_space at
libdrm-2.4.95/intel/intel_bufmgr_gem.c,
it is seen that the deadlock-abort is occurring at total_fences == 16,
where the previous display shows total_fences == 14,
so there is an increment of 2 fences in stead of the usual increment of 1.
Apparently the deadlock occurs at the "freeing fences phase", that is started
if total_fences is too high.
I decided to lower the available_fences from 14 to 13 (see proposed patch).
This solved the problem.
After this patch I still saw sometimes total_fences == 16,
where the previous display shows total_fences == 13, so there is an increment
of 3 fences. This did not cause a deadlock at the "freeing fences phase".

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1861 bytes --]

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

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 309 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #4 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
Created attachment 143231
  --> https://bugs.freedesktop.org/attachment.cgi?id=143231&action=edit
libdrm-patch

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1340 bytes --]

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

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 2044 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #5 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
Some more investigation, understanding and adding 2 other possible fixes for
the problem.
The problem occurs at Ubuntu 18.10 only at gdm3 with wayland using dual
monitor.
It is not occuring with wayland at single monitor.
It totally doesnot occur if gdm3 is not using wayland.
At ubuntu 18.04 the same problem exists with wayland, but is not occurring so
often.

At ubuntu 18.10 with wayland and dual monitor the user session immediately
aborts, if 16 or more favorites are allocated at the dock.
For some reason wayland seems to use one extra fence register at dual monitor.
It is noticed at dual monitor, that gdm3 with wayland uses 2 calls to
clutter_stage_cogl_redraw_view for 2 logical screens for every call to
clutter_stage_cogl_redraw; gdm3 without wayland does only one call to
clutter_stage_cogl_redraw_view for 1 logical screen.

The crash occurs at intel_batchbuffer_flush. Always the last batch at such a
flush is coming from function emit_copy_blit and intelClearWithBlit at
src/mesa/drivers/dri/i915/intel_blit.c. At the call to
dri_bufmgr_check_aperture_space they indicate to use zero fence registers, but
in fact they use one. This violates the limit of 14, causing a crash at dual
monitor.
So the call to dri_bufmgr_check_aperture_space must be postponed, until the
needed fence register is added in the middle of the batch-generation and then
the batch-actions must be undone, a flush is called and batch is regenerated
again.
For this function intel_batchbuffer_emit_reset is added.
This also is done for function intel_miptree_set_alpha_to_one, although I never
saw a call of this function.
See fix error3_patch2.txt.

Another (dirty) solution is to decrement the availablity and just continue.
This gives somewhere a failure, but I could not see a failing layout.
See fix error3_patch3.txt.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2873 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 333 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #6 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
Created attachment 143414
  --> https://bugs.freedesktop.org/attachment.cgi?id=143414&action=edit
fix intel_blit.c

fix error_patch2

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1372 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 319 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #7 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
Created attachment 143415
  --> https://bugs.freedesktop.org/attachment.cgi?id=143415&action=edit
libdrm_ignore_deadlock

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1370 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 609 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

--- Comment #8 from Gert vd Kraats <vd.kraats@hccnet.nl> ---
I am currently using Debian 10 Buster with Wayland.
This problem is not existing anymore at this release.
Wayland no longer uses an extra fence register if dual monitor is used.

The wrong reservation of fence registers at intel_blit.c still exists, but does
not harm, because the limit of 14 usable fence registers is very safe.
A limit of 15 might be possible, if reservation at intel_blit.c is unbugged.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1438 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 109102] At dual monitor intel_do_flush_locked failed: Resource deadlock avoided

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 841 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=109102

GitLab Migration User <gitlab-migration@fdo.invalid> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |MOVED

--- Comment #9 from GitLab Migration User <gitlab-migration@fdo.invalid> ---
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been
closed from further activity.

You can subscribe and participate further through the new bug through this link
to our GitLab instance: https://gitlab.freedesktop.org/mesa/mesa/issues/790.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2509 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel