blob: e71e3558c289bfbd774e122700113e382e384d77 [file] [log] [blame]
* Copyright 2017 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#ifndef GrResourceAllocator_DEFINED
#define GrResourceAllocator_DEFINED
#include "GrGpuResourcePriv.h"
#include "GrSurface.h"
#include "GrSurfaceProxy.h"
#include "SkArenaAlloc.h"
#include "SkTDynamicHash.h"
#include "SkTMultiMap.h"
class GrResourceProvider;
class GrUninstantiateProxyTracker;
* The ResourceAllocator explicitly distributes GPU resources at flush time. It operates by
* being given the usage intervals of the various proxies. It keeps these intervals in a singly
* linked list sorted by increasing start index. (It also maintains a hash table from proxyID
* to interval to find proxy reuse). When it comes time to allocate the resources it
* traverses the sorted list and:
* removes intervals from the active list that have completed (returning their GrSurfaces
* to the free pool)
* allocates a new resource (preferably from the free pool) for the new interval
* adds the new interval to the active list (that is sorted by increasing end index)
* Note: the op indices (used in the usage intervals) come from the order of the ops in
* their opLists after the opList DAG has been linearized.
class GrResourceAllocator {
GrResourceAllocator(GrResourceProvider* resourceProvider)
: fResourceProvider(resourceProvider) {
unsigned int curOp() const { return fNumOps; }
void incOps() { fNumOps++; }
unsigned int numOps() const { return fNumOps; }
// Add a usage interval from 'start' to 'end' inclusive. This is usually used for renderTargets.
// If an existing interval already exists it will be expanded to include the new range.
void addInterval(GrSurfaceProxy*, unsigned int start, unsigned int end
SkDEBUGCODE(, bool isDirectDstRead = false));
// Add an interval that spans just the current op. Usually this is for texture uses.
// If an existing interval already exists it will be expanded to include the new operation.
void addInterval(GrSurfaceProxy* proxy
SkDEBUGCODE(, bool isDirectDstRead = false)) {
this->addInterval(proxy, fNumOps, fNumOps SkDEBUGCODE(, isDirectDstRead));
enum class AssignError {
// Returns true when the opLists from 'startIndex' to 'stopIndex' should be executed;
// false when nothing remains to be executed.
// If any proxy fails to instantiate, the AssignError will be set to kFailedProxyInstantiation.
// If this happens, the caller should remove all ops which reference an uninstantiated proxy.
// This is used to execute a portion of the queued opLists in order to reduce the total
// amount of GPU resources required.
bool assign(int* startIndex, int* stopIndex, GrUninstantiateProxyTracker*,
AssignError* outError);
void markEndOfOpList(int opListIndex);
class Interval;
// Remove dead intervals from the active list
void expire(unsigned int curIndex);
// These two methods wrap the interactions with the free pool
void freeUpSurface(sk_sp<GrSurface> surface);
sk_sp<GrSurface> findSurfaceFor(const GrSurfaceProxy* proxy, bool needsStencil);
struct FreePoolTraits {
static const GrScratchKey& GetKey(const GrSurface& s) {
return s.resourcePriv().getScratchKey();
static uint32_t Hash(const GrScratchKey& key) { return key.hash(); }
static void OnFree(GrSurface* s) { s->unref(); }
typedef SkTMultiMap<GrSurface, GrScratchKey, FreePoolTraits> FreePoolMultiMap;
typedef SkTDynamicHash<Interval, unsigned int> IntvlHash;
class Interval {
Interval(GrSurfaceProxy* proxy, unsigned int start, unsigned int end)
: fProxy(proxy)
, fProxyID(proxy->uniqueID().asUInt())
, fStart(start)
, fEnd(end)
, fNext(nullptr) {
void resetTo(GrSurfaceProxy* proxy, unsigned int start, unsigned int end) {
fProxy = proxy;
fProxyID = proxy->uniqueID().asUInt();
fStart = start;
fEnd = end;
fNext = nullptr;
~Interval() {
const GrSurfaceProxy* proxy() const { return fProxy; }
GrSurfaceProxy* proxy() { return fProxy; }
unsigned int start() const { return fStart; }
unsigned int end() const { return fEnd; }
const Interval* next() const { return fNext; }
Interval* next() { return fNext; }
void setNext(Interval* next) { fNext = next; }
void extendEnd(unsigned int newEnd) {
if (newEnd > fEnd) {
fEnd = newEnd;
void assign(sk_sp<GrSurface>);
bool wasAssignedSurface() const { return fAssignedSurface != nullptr; }
sk_sp<GrSurface> detachSurface() { return std::move(fAssignedSurface); }
// for SkTDynamicHash
static const uint32_t& GetKey(const Interval& intvl) {
return intvl.fProxyID;
static uint32_t Hash(const uint32_t& key) { return key; }
sk_sp<GrSurface> fAssignedSurface;
GrSurfaceProxy* fProxy;
uint32_t fProxyID; // This is here b.c. DynamicHash requires a ref to the key
unsigned int fStart;
unsigned int fEnd;
Interval* fNext;
class IntervalList {
IntervalList() = default;
~IntervalList() {
// The only time we delete an IntervalList is in the GrResourceAllocator dtor.
// Since the arena allocator will clean up for us we don't bother here.
bool empty() const { return !SkToBool(fHead); }
const Interval* peekHead() const { return fHead; }
Interval* popHead();
void insertByIncreasingStart(Interval*);
void insertByIncreasingEnd(Interval*);
Interval* detachAll();
Interval* fHead = nullptr;
// Gathered statistics indicate that 99% of flushes will be covered by <= 12 Intervals
static const int kInitialArenaSize = 12 * sizeof(Interval);
GrResourceProvider* fResourceProvider;
FreePoolMultiMap fFreePool; // Recently created/used GrSurfaces
IntvlHash fIntvlHash; // All the intervals, hashed by proxyID
IntervalList fIntvlList; // All the intervals sorted by increasing start
IntervalList fActiveIntvls; // List of live intervals during assignment
// (sorted by increasing end)
unsigned int fNumOps = 1; // op # 0 is reserved for uploads at the start
// of a flush
SkTArray<unsigned int> fEndOfOpListOpIndices;
int fCurOpListIndex = 0;
SkDEBUGCODE(bool fAssigned = false;)
char fStorage[kInitialArenaSize];
SkArenaAlloc fIntervalAllocator { fStorage, kInitialArenaSize, 0 };
Interval* fFreeIntervalList = nullptr;
#endif // GrResourceAllocator_DEFINED