From: Lucas Stach <l.stach@pengutronix.de>
Date: Fri, 25 May 2018 16:51:25 +0200
Subject: drm/etnaviv: protect sched job submission with fence mutex
Git-commit: a0780bb1df60f00e4573db7bd53e7039e9eee1cb
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
The documentation of drm_sched_job_init and drm_sched_entity_push_job has
been clarified. Both functions should be called under a shared lock, to
avoid jobs getting pushed into the scheduler queue in a different order
than their sched_fence seqnos, which will confuse checks that are looking
at the seqnos to infer information about completion order.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c | 4 ++--
drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 2 +-
drivers/gpu/drm/etnaviv/etnaviv_gpu.h | 2 +-
drivers/gpu/drm/etnaviv/etnaviv_sched.c | 24 +++++++++++++++++-------
4 files changed, 21 insertions(+), 11 deletions(-)
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
@@ -388,9 +388,9 @@ static void submit_cleanup(struct kref *
dma_fence_put(submit->in_fence);
if (submit->out_fence) {
/* first remove from IDR, so fence can not be found anymore */
- mutex_lock(&submit->gpu->fence_idr_lock);
+ mutex_lock(&submit->gpu->fence_lock);
idr_remove(&submit->gpu->fence_idr, submit->out_fence_id);
- mutex_unlock(&submit->gpu->fence_idr_lock);
+ mutex_unlock(&submit->gpu->fence_lock);
dma_fence_put(submit->out_fence);
}
kfree(submit->pmrs);
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1726,7 +1726,7 @@ static int etnaviv_gpu_platform_probe(st
gpu->dev = &pdev->dev;
mutex_init(&gpu->lock);
- mutex_init(&gpu->fence_idr_lock);
+ mutex_init(&gpu->fence_lock);
/* Map registers: */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
@@ -118,7 +118,7 @@ struct etnaviv_gpu {
u32 idle_mask;
/* Fencing support */
- struct mutex fence_idr_lock;
+ struct mutex fence_lock;
struct idr fence_idr;
u32 next_fence;
u32 active_fence;
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
@@ -140,28 +140,38 @@ static const struct drm_sched_backend_op
int etnaviv_sched_push_job(struct drm_sched_entity *sched_entity,
struct etnaviv_gem_submit *submit)
{
- int ret;
+ int ret = 0;
+
+ /*
+ * Hold the fence lock across the whole operation to avoid jobs being
+ * pushed out of order with regard to their sched fence seqnos as
+ * allocated in drm_sched_job_init.
+ */
+ mutex_lock(&submit->gpu->fence_lock);
ret = drm_sched_job_init(&submit->sched_job, sched_entity,
submit->cmdbuf.ctx);
if (ret)
- return ret;
+ goto out_unlock;
submit->out_fence = dma_fence_get(&submit->sched_job.s_fence->finished);
- mutex_lock(&submit->gpu->fence_idr_lock);
submit->out_fence_id = idr_alloc_cyclic(&submit->gpu->fence_idr,
submit->out_fence, 0,
INT_MAX, GFP_KERNEL);
- mutex_unlock(&submit->gpu->fence_idr_lock);
- if (submit->out_fence_id < 0)
- return -ENOMEM;
+ if (submit->out_fence_id < 0) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
/* the scheduler holds on to the job now */
kref_get(&submit->refcount);
drm_sched_entity_push_job(&submit->sched_job, sched_entity);
- return 0;
+out_unlock:
+ mutex_unlock(&submit->gpu->fence_lock);
+
+ return ret;
}
int etnaviv_sched_init(struct etnaviv_gpu *gpu)