diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch')
-rw-r--r-- | target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch | 81 |
1 files changed, 46 insertions, 35 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch b/target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch index 75adab38d9..36843e1c3a 100644 --- a/target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch +++ b/target/linux/brcm2708/patches-4.4/0096-drm-vc4-Drop-struct_mutex-around-CL-validation.patch @@ -1,63 +1,74 @@ -From 4dc15a296586679d5b014011e44a093cf962123e Mon Sep 17 00:00:00 2001 +From 4b137e2962b14c62089f4368391fa1ed03cac391 Mon Sep 17 00:00:00 2001 From: Eric Anholt <eric@anholt.net> Date: Mon, 19 Oct 2015 08:44:35 -0700 -Subject: [PATCH 096/170] drm/vc4: Drop struct_mutex around CL validation. +Subject: [PATCH 096/381] drm/vc4: Drop struct_mutex around CL validation. We were using it so that we could make sure that shader validation state didn't change while we were validating, but now shader validation state is immutable. The bcl/rcl generation doesn't do any other BO dereferencing, and seems to have no other global state -dependency not covered by job_lock / bo_lock. +dependency not covered by job_lock / bo_lock. We only need to hold +struct_mutex for object unreferencing. Fixes a lock order reversal between mmap_sem and struct_mutex. Signed-off-by: Eric Anholt <eric@anholt.net> --- - drivers/gpu/drm/vc4/vc4_gem.c | 12 ++++-------- - 1 file changed, 4 insertions(+), 8 deletions(-) + drivers/gpu/drm/vc4/vc4_gem.c | 13 ++++++------- + 1 file changed, 6 insertions(+), 7 deletions(-) --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c -@@ -244,13 +244,15 @@ static void - vc4_queue_submit(struct drm_device *dev, struct vc4_exec_info *exec) +@@ -439,10 +439,12 @@ fail: + } + + static void +-vc4_complete_exec(struct vc4_exec_info *exec) ++vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) { - struct vc4_dev *vc4 = to_vc4_dev(dev); -- uint64_t seqno = ++vc4->emit_seqno; -+ uint64_t seqno; - unsigned long irqflags; + unsigned i; -+ spin_lock_irqsave(&vc4->job_lock, irqflags); -+ -+ seqno = ++vc4->emit_seqno; - exec->seqno = seqno; - vc4_update_bo_seqnos(exec, seqno); ++ /* Need the struct lock for drm_gem_object_unreference(). */ ++ mutex_lock(&dev->struct_mutex); + if (exec->bo) { + for (i = 0; i < exec->bo_count; i++) + drm_gem_object_unreference(&exec->bo[i].bo->base); +@@ -455,6 +457,7 @@ vc4_complete_exec(struct vc4_exec_info * + list_del(&bo->unref_head); + drm_gem_object_unreference(&bo->base.base); + } ++ mutex_unlock(&dev->struct_mutex); -- spin_lock_irqsave(&vc4->job_lock, irqflags); - list_add_tail(&exec->head, &vc4->job_list); + kfree(exec); + } +@@ -473,7 +476,7 @@ vc4_job_handle_completed(struct vc4_dev + list_del(&exec->head); - /* If no job was executing, kick ours off. Otherwise, it'll -@@ -608,8 +610,6 @@ vc4_submit_cl_ioctl(struct drm_device *d - exec->args = args; - INIT_LIST_HEAD(&exec->unref_list); + spin_unlock_irqrestore(&vc4->job_lock, irqflags); +- vc4_complete_exec(exec); ++ vc4_complete_exec(vc4->dev, exec); + spin_lock_irqsave(&vc4->job_lock, irqflags); + } -- mutex_lock(&dev->struct_mutex); -- - ret = vc4_cl_lookup_bos(dev, file_priv, exec); - if (ret) - goto fail; -@@ -636,15 +636,11 @@ vc4_submit_cl_ioctl(struct drm_device *d - /* Return the seqno for our job. */ - args->seqno = vc4->emit_seqno; +@@ -525,12 +528,8 @@ vc4_job_done_work(struct work_struct *wo + { + struct vc4_dev *vc4 = + container_of(work, struct vc4_dev, job_done_work); +- struct drm_device *dev = vc4->dev; +- /* Need the struct lock for drm_gem_object_unreference(). */ +- mutex_lock(&dev->struct_mutex); + vc4_job_handle_completed(vc4); - mutex_unlock(&dev->struct_mutex); -- + } + + static int +@@ -639,7 +638,7 @@ vc4_submit_cl_ioctl(struct drm_device *d return 0; fail: - vc4_complete_exec(exec); +- vc4_complete_exec(exec); ++ vc4_complete_exec(vc4->dev, exec); -- mutex_unlock(&dev->struct_mutex); -- return ret; } - |