kernel/linux.git/drivers/gpu/drm/msm/msm_gpu.c, branch linux-5.11.y

drm/msm: Protect obj->active_count under obj lock

2020-11-21T17:50:23+00:00

Previously we only held obj lock in the _active_get() path, and relied on atomic_dec_return() to not be racy in the _active_put() path where obj lock was not held. But this is a false sense of security. Unlike obj lifetime refcnt, where you do not expect to *increase* the refcnt after the last put (which would mean that something has gone horribly wrong with the object liveness reference counting), the active_count can increase again from zero. Racing _active_put()s and _active_get()s could leave the obj on the wrong mm list. But in the retire path, immediately after the _active_put(), the _unpin_iova() would acquire obj lock. So just move the locking earlier and rely on that to protect obj->active_count. Fixes: c5c1643cef7a ("drm/msm: Drop struct_mutex from the retire path") Signed-off-by: Rob Clark

drm/msm: Add support for GPU cooling

2020-11-05T16:39:57+00:00

Register GPU as a devfreq cooling device so that it can be passively cooled by the thermal framework. Signed-off-by: Akhil P Oommen Tested-by: Matthias Kaehlcke Signed-off-by: Rob Clark

drm/msm: Drop struct_mutex from the retire path

2020-11-05T00:00:56+00:00

Now that we are not relying on dev->struct_mutex to protect the ring->submits lists, drop the struct_mutex lock. Signed-off-by: Rob Clark Reviewed-by: Jordan Crouse Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Remove obj->gpu

2020-11-05T00:00:56+00:00

It cannot be atomically updated with obj->active_count, and the only purpose is a useless WARN_ON() (which becomes a buggy WARN_ON() once retire_submits() is not serialized with incoming submits via struct_mutex) Signed-off-by: Rob Clark Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Refcount submits

2020-11-05T00:00:56+00:00

Before we remove dev->struct_mutex from the retire path, we have to deal with the situation of a submit retiring before the submit ioctl returns. To deal with this, ring->submits will hold a reference to the submit, which is dropped when the submit is retired. And the submit ioctl path holds it's own ref, which it drops when it is done with the submit. Also, add to submit list *after* getting/pinning bo's, to prevent badness in case the completed fence is corrupted, and retire_worker mistakenly believes the submit is done too early. Signed-off-by: Rob Clark Reviewed-by: Jordan Crouse Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Protect ring->submits with it's own lock

2020-11-05T00:00:56+00:00

One less place to rely on dev->struct_mutex. Signed-off-by: Rob Clark Reviewed-by: Jordan Crouse Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Move update_fences()

2020-11-05T00:00:56+00:00

Small cleanup, update_fences() is used in the hangcheck path, but also in the normal retire path. Signed-off-by: Rob Clark Reviewed-by: Jordan Crouse Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Drop chatty trace

2020-11-05T00:00:56+00:00

It is somewhat redundant with the gpu tracepoints, and anyways not too useful to justify spamming the log when debug traces are enabled. Signed-off-by: Rob Clark Reviewed-by: Jordan Crouse Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm/gem: Switch over to obj->resv for locking

2020-11-05T00:00:56+00:00

This also converts the special msm_gem_get_vaddr_active() to expect the lock to already be held. There are two call-sites for this, one already has the lock held, so it is more straightforward to just open-code the locking for the other caller. Signed-off-by: Rob Clark Reviewed-by: Kristian H. Kristensen Signed-off-by: Rob Clark

drm/msm: Remove redundant null check

2020-11-04T16:26:26+00:00

clk_prepare_enable() and clk_disable_unprepare() will check NULL clock parameter, so It is not necessary to add additional checks. Signed-off-by: Tian Tao Reviewed-by: Jordan Crouse Signed-off-by: Rob Clark