diff options
author | Andrey Grodzovsky <andrey.grodzovsky@amd.com> | 2022-06-20 23:39:47 +0300 |
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committer | Alex Deucher <alexander.deucher@amd.com> | 2022-06-28 18:24:31 +0300 |
commit | 45ecaea738830b9d521c93520c8f201359dcbd95 (patch) | |
tree | aaee09e4aaa7fd0ea8adc343e7ea59f3dbd61880 /drivers/gpu/drm/scheduler | |
parent | 9e225fb9e636b31b97e9d35324c2f9e43ee0aab4 (diff) | |
download | linux-45ecaea738830b9d521c93520c8f201359dcbd95.tar.xz |
drm/sched: Partial revert of 'drm/sched: Keep s_fence->parent pointer'
Problem:
This patch caused negative refcount as described in [1] because
for that case parent fence did not signal by the time of drm_sched_stop and hence
kept in pending list the assumption was they will not signal and
so fence was put to account for the s_fence->parent refcount but for
amdgpu which has embedded HW fence (always same parent fence)
drm_sched_fence_release_scheduled was always called and would
still drop the count for parent fence once more. For jobs that
never signaled this imbalance was masked by refcount bug in
amdgpu_fence_driver_clear_job_fences that would not drop
refcount on the fences that were removed from fence drive
fences array (against prevois insertion into the array in
get in amdgpu_fence_emit).
Fix:
Revert this patch and by setting s_job->s_fence->parent to NULL
as before prevent the extra refcount drop in amdgpu when
drm_sched_fence_release_scheduled is called on job release.
Also - align behaviour in drm_sched_resubmit_jobs_ext with that of
drm_sched_main when submitting jobs - take a refcount for the
new parent fence pointer and drop refcount for original kref_init
for new HW fence creation (or fake new HW fence in amdgpu - see next patch).
[1] - https://lore.kernel.org/all/731b7ff1-3cc9-e314-df2a-7c51b76d4db0@amd.com/t/#r00c728fcc069b1276642c325bfa9d82bf8fa21a3
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Tested-by: Yiqing Yao <yiqing.yao@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/scheduler')
-rw-r--r-- | drivers/gpu/drm/scheduler/sched_main.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 76fd2904c7c6..68317d3a7a27 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -419,6 +419,8 @@ void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad) if (s_job->s_fence->parent && dma_fence_remove_callback(s_job->s_fence->parent, &s_job->cb)) { + dma_fence_put(s_job->s_fence->parent); + s_job->s_fence->parent = NULL; atomic_dec(&sched->hw_rq_count); } else { /* @@ -548,7 +550,6 @@ void drm_sched_resubmit_jobs_ext(struct drm_gpu_scheduler *sched, int max) if (found_guilty && s_job->s_fence->scheduled.context == guilty_context) dma_fence_set_error(&s_fence->finished, -ECANCELED); - dma_fence_put(s_job->s_fence->parent); fence = sched->ops->run_job(s_job); i++; @@ -558,7 +559,11 @@ void drm_sched_resubmit_jobs_ext(struct drm_gpu_scheduler *sched, int max) s_job->s_fence->parent = NULL; } else { - s_job->s_fence->parent = fence; + + s_job->s_fence->parent = dma_fence_get(fence); + + /* Drop for orignal kref_init */ + dma_fence_put(fence); } } } @@ -955,6 +960,9 @@ static int drm_sched_main(void *param) if (!IS_ERR_OR_NULL(fence)) { s_fence->parent = dma_fence_get(fence); + /* Drop for original kref_init of the fence */ + dma_fence_put(fence); + r = dma_fence_add_callback(fence, &sched_job->cb, drm_sched_job_done_cb); if (r == -ENOENT) @@ -962,7 +970,6 @@ static int drm_sched_main(void *param) else if (r) DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r); - dma_fence_put(fence); } else { if (IS_ERR(fence)) dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); |