drm: Add reference counting to drm_atomic_state
drm_atomic_state has a complicated single owner model that tracks the
single reference from allocation through to destruction on another
thread - or perhaps on a local error path. We can simplify this tracking
by using reference counting (at a cost of a few more atomics). This is
even more beneficial when the lifetime of the state becomes more
convoluted than being passed to a single worker thread for the commit.
v2: Double check !intel atomic_commit functions for missing gets
v3: Update kerneldocs
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161014121833.439-27-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index ad8d712..a12e093 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3582,7 +3582,7 @@
return;
err:
- drm_atomic_state_free(state);
+ drm_atomic_state_put(state);
}
void intel_finish_reset(struct drm_i915_private *dev_priv)
@@ -3643,6 +3643,8 @@
intel_hpd_init(dev_priv);
}
+ if (state)
+ drm_atomic_state_put(state);
drm_modeset_drop_locks(ctx);
drm_modeset_acquire_fini(ctx);
mutex_unlock(&dev->mode_config.mutex);
@@ -6882,7 +6884,7 @@
dev_priv->display.crtc_disable(crtc_state, state);
- drm_atomic_state_free(state);
+ drm_atomic_state_put(state);
DRM_DEBUG_KMS("[CRTC:%d:%s] hw state adjusted, was enabled, now disabled\n",
crtc->base.id, crtc->name);
@@ -11249,8 +11251,8 @@
return true;
fail:
- drm_atomic_state_free(state);
- drm_atomic_state_free(restore_state);
+ drm_atomic_state_put(state);
+ drm_atomic_state_put(restore_state);
restore_state = state = NULL;
if (ret == -EDEADLK) {
@@ -11279,10 +11281,9 @@
return;
ret = drm_atomic_commit(state);
- if (ret) {
+ if (ret)
DRM_DEBUG_KMS("Couldn't release load detect pipe: %i\n", ret);
- drm_atomic_state_free(state);
- }
+ drm_atomic_state_put(state);
}
static int i9xx_pll_refclk(struct drm_device *dev,
@@ -12350,8 +12351,7 @@
goto retry;
}
- if (ret)
- drm_atomic_state_free(state);
+ drm_atomic_state_put(state);
if (ret == 0 && event) {
spin_lock_irq(&dev->event_lock);
@@ -14437,7 +14437,7 @@
drm_atomic_helper_commit_cleanup_done(state);
- drm_atomic_state_free(state);
+ drm_atomic_state_put(state);
/* As one of the primary mmio accessors, KMS has a high likelihood
* of triggering bugs in unclaimed access. After we finish
@@ -14520,6 +14520,7 @@
intel_shared_dpll_commit(state);
intel_atomic_track_fbs(state);
+ drm_atomic_state_get(state);
if (nonblock)
queue_work(system_unbound_wq, &state->commit_work);
else
@@ -14561,9 +14562,8 @@
goto retry;
}
- if (ret)
out:
- drm_atomic_state_free(state);
+ drm_atomic_state_put(state);
}
/*
@@ -16305,8 +16305,8 @@
dev_priv->display.optimize_watermarks(cs);
}
- drm_atomic_state_free(state);
fail:
+ drm_atomic_state_put(state);
drm_modeset_drop_locks(&ctx);
drm_modeset_acquire_fini(&ctx);
}
@@ -16943,10 +16943,9 @@
drm_modeset_acquire_fini(&ctx);
mutex_unlock(&dev->mode_config.mutex);
- if (ret) {
+ if (ret)
DRM_ERROR("Restoring old state failed with %i\n", ret);
- drm_atomic_state_free(state);
- }
+ drm_atomic_state_put(state);
}
void intel_modeset_gem_init(struct drm_device *dev)