diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0540-drm-vc4-Use-drm_gem_object_unreference_unlocked.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0540-drm-vc4-Use-drm_gem_object_unreference_unlocked.patch | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0540-drm-vc4-Use-drm_gem_object_unreference_unlocked.patch b/target/linux/brcm2708/patches-4.4/0540-drm-vc4-Use-drm_gem_object_unreference_unlocked.patch new file mode 100644 index 0000000..97afbed --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0540-drm-vc4-Use-drm_gem_object_unreference_unlocked.patch @@ -0,0 +1,76 @@ +From 180aed47cc2cc41b8669e9e6c61f79bf1b018fed Mon Sep 17 00:00:00 2001 +From: Daniel Vetter <daniel.vetter@ffwll.ch> +Date: Mon, 30 May 2016 19:53:06 +0200 +Subject: [PATCH] drm/vc4: Use drm_gem_object_unreference_unlocked + +Since my last struct_mutex crusade someone escaped! + +This already has the advantage that for the common case when someone +else holds a ref the unref won't even acquire dev->struct_mutex. And +I'm working on code to allow drivers to completely opt-out of any and +all dev->struct_mutex usage, but that only works if they use the +_unlocked variants everywhere. + +v2: Drop comment too. + +v3: Drop the other comment too. + +Cc: Eric Anholt <eric@anholt.net> +Reviewed-by: Eric Anholt <eric@anholt.net> +Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> +Link: http://patchwork.freedesktop.org/patch/msgid/1464630800-30786-15-git-send-email-daniel.vetter@ffwll.ch +(cherry picked from commit db3697295cf4da1356e3ec86761d464d6d013b48) +--- + drivers/gpu/drm/vc4/vc4_bo.c | 2 -- + drivers/gpu/drm/vc4/vc4_gem.c | 11 +++-------- + 2 files changed, 3 insertions(+), 10 deletions(-) + +--- a/drivers/gpu/drm/vc4/vc4_bo.c ++++ b/drivers/gpu/drm/vc4/vc4_bo.c +@@ -311,8 +311,6 @@ static void vc4_bo_cache_free_old(struct + + /* Called on the last userspace/kernel unreference of the BO. Returns + * it to the BO cache if possible, otherwise frees it. +- * +- * Note that this is called with the struct_mutex held. + */ + void vc4_free_object(struct drm_gem_object *gem_bo) + { +--- a/drivers/gpu/drm/vc4/vc4_gem.c ++++ b/drivers/gpu/drm/vc4/vc4_gem.c +@@ -67,10 +67,8 @@ vc4_free_hang_state(struct drm_device *d + { + unsigned int i; + +- mutex_lock(&dev->struct_mutex); + for (i = 0; i < state->user_state.bo_count; i++) +- drm_gem_object_unreference(state->bo[i]); +- mutex_unlock(&dev->struct_mutex); ++ drm_gem_object_unreference_unlocked(state->bo[i]); + + kfree(state); + } +@@ -711,11 +709,9 @@ vc4_complete_exec(struct drm_device *dev + struct vc4_dev *vc4 = to_vc4_dev(dev); + unsigned i; + +- /* 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]->base); ++ drm_gem_object_unreference_unlocked(&exec->bo[i]->base); + kfree(exec->bo); + } + +@@ -723,9 +719,8 @@ vc4_complete_exec(struct drm_device *dev + struct vc4_bo *bo = list_first_entry(&exec->unref_list, + struct vc4_bo, unref_head); + list_del(&bo->unref_head); +- drm_gem_object_unreference(&bo->base.base); ++ drm_gem_object_unreference_unlocked(&bo->base.base); + } +- mutex_unlock(&dev->struct_mutex); + + mutex_lock(&vc4->power_lock); + if (--vc4->power_refcount == 0) { |