hwc: Add GPU-preferred and MDP-preferred modes to load based comp.
GPU's perf is proportional to the number of pixels it processes, so
the load based strategy that prefers GPU, attempts to load it less
in terms of pixels, and at the same time makes sure the MDP has
enough pipes and mixer stages.
MDP's perf is real time and proportional to the instantaneous b/w
which is a function of overlaps. So the load based strategy that
prefers MDP would look at sending only as many full-screen layers
that MDP could support.
This mode is used when the GPU-preferred mode fails.
Change-Id: I3221a94bb01c43112370c248cd4ab217f2bd8ed1
diff --git a/libhwcomposer/hwc_mdpcomp.cpp b/libhwcomposer/hwc_mdpcomp.cpp
index ec9f215..2a1b123 100644
--- a/libhwcomposer/hwc_mdpcomp.cpp
+++ b/libhwcomposer/hwc_mdpcomp.cpp
@@ -605,7 +605,8 @@
bool ret = false;
if(isLoadBasedCompDoable(ctx, list)) {
- ret = loadBasedComp(ctx, list);
+ ret = loadBasedCompPreferGPU(ctx, list) ||
+ loadBasedCompPreferMDP(ctx, list);
}
if(!ret) {
@@ -657,14 +658,16 @@
return true;
}
-bool MDPComp::loadBasedComp(hwc_context_t *ctx,
+bool MDPComp::loadBasedCompPreferGPU(hwc_context_t *ctx,
hwc_display_contents_1_t* list) {
int numAppLayers = ctx->listStats[mDpy].numAppLayers;
mCurrentFrame.reset(numAppLayers);
- //TODO BatchSize could be optimized further based on available pipes, split
- //displays etc.
- const int batchSize = numAppLayers - (sMaxPipesPerMixer - 1);
+ int stagesForMDP = min(sMaxPipesPerMixer, ctx->mOverlay->availablePipes(
+ mDpy, Overlay::MIXER_DEFAULT));
+ //If MDP has X possible stages, it can take X layers.
+ const int batchSize = numAppLayers - (stagesForMDP - 1); //1 for FB
+
if(batchSize <= 0) {
ALOGD_IF(isDebug(), "%s: Not attempting", __FUNCTION__);
return false;
@@ -720,6 +723,59 @@
return true;
}
+bool MDPComp::loadBasedCompPreferMDP(hwc_context_t *ctx,
+ hwc_display_contents_1_t* list) {
+ const int numAppLayers = ctx->listStats[mDpy].numAppLayers;
+ //TODO get the ib from sysfs node.
+ //Full screen is from ib perspective, not actual full screen
+ const int bpp = 4;
+ double panelRefRate =
+ 1000000000.0 / ctx->dpyAttr[mDpy].vsync_period;
+
+ double bwLeft = sMaxBw - sBwClaimed;
+
+ const int fullScreenLayers = bwLeft * 1000000000 / (ctx->dpyAttr[mDpy].xres
+ * ctx->dpyAttr[mDpy].yres * bpp * panelRefRate);
+
+ const int fbBatchSize = numAppLayers - (fullScreenLayers - 1);
+ //If batch size is not at least 2, we aren't really preferring MDP, since
+ //only 1 layer going to GPU could actually translate into an entire FB
+ //needed to be fetched by MDP, thus needing more b/w rather than less.
+ if(fbBatchSize < 2 || fbBatchSize > numAppLayers) {
+ ALOGD_IF(isDebug(), "%s: Not attempting", __FUNCTION__);
+ return false;
+ }
+
+ //Top-most layers constitute FB batch
+ const int fbBatchStart = numAppLayers - fbBatchSize;
+
+ //Bottom-most layers constitute MDP batch
+ for(int i = 0; i < fbBatchStart; i++) {
+ hwc_layer_1_t* layer = &list->hwLayers[i];
+ if(not isSupportedForMDPComp(ctx, layer)) {
+ ALOGD_IF(isDebug(), "%s: MDP unsupported layer found at %d",
+ __FUNCTION__, i);
+ return false;
+ }
+ mCurrentFrame.isFBComposed[i] = false;
+ }
+
+ mCurrentFrame.fbZ = fbBatchStart;
+ mCurrentFrame.fbCount = fbBatchSize;
+ mCurrentFrame.mdpCount = mCurrentFrame.layerCount - fbBatchSize;
+
+ if(!resourceCheck(ctx, list)) {
+ ALOGD_IF(isDebug(), "%s: resource check failed", __FUNCTION__);
+ return false;
+ }
+
+ ALOGD_IF(isDebug(), "%s: FB Z %d, num app layers %d, MDP Batch Size %d",
+ __FUNCTION__, mCurrentFrame.fbZ, numAppLayers,
+ numAppLayers - fbBatchSize);
+
+ return true;
+}
+
bool MDPComp::isLoadBasedCompDoable(hwc_context_t *ctx,
hwc_display_contents_1_t* list) {
if(mDpy or isSecurePresent(ctx, mDpy) or
@@ -736,7 +792,6 @@
mCurrentFrame.reset(numAppLayers);
updateYUV(ctx, list, secureOnly);
int mdpCount = mCurrentFrame.mdpCount;
- int fbNeeded = (mCurrentFrame.fbCount != 0);
if(!isYuvPresent(ctx, mDpy)) {
return false;