[Bug 100712] ring 0 stalled after bytes_moved_threshold reached - Cap Verde - HD 7770

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=100712

            Bug ID: 100712
           Summary: ring 0 stalled after bytes_moved_threshold reached -
                    Cap Verde - HD 7770
           Product: DRI
           Version: DRI git
          Hardware: Other
                OS: All
            Status: NEW
          Severity: normal
          Priority: medium
         Component: DRM/Radeon
          Assignee: dri-devel at lists.freedesktop.org
          Reporter: julien.isorce at gmail.com

Kernel 4.9 from
https://cgit.freedesktop.org/~agd5f/linux/log/?h=amd-staging-4.9 and latest
mesa. (same result with drm-next-4.12 branch)
Same result with kernel 4.8 and mesa 12.0.6.

In kernel radeon_object.c::radeon_bo_list_validate, once "bytes_moved >
bytes_moved_threshold" is reached (this is the case for 850 bo in the same
list_for_each_entry loop), I can see that radeon_ib_schedule emits a fence that
it takes more than the radeon.lockup_timeout to be signaled.

In radeon_fence_activity, I checked that the "last_emitted" is the seq number
for this last emited fence. And last_seq is equal to last_emitted-1.

Then the next call to ttm_wait_bo blocks (15 * HZ > radeon.lockup_timeout)
until gpu lockup which leads to a gpu reset.

Also it seems the fence is signaled by swapper after more than 10 seconds but
it is too late. I requires to reduce the "15" param above to 4 to see that.

Is it normal that radeon_bo_list_validate still tries to move the bo if
bytes_moved_threshold is reached ? Indeed ttm_bo_validate is always called (it
blits from vram to vram).
Is it also normal that ttm_bo_validate is called with evict flag as true once
bytes_moved_threshold is reached ?

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20170418/b460b4f1/attachment.html>