Index: gpu/command_buffer/client/query_tracker.cc |
diff --git a/gpu/command_buffer/client/query_tracker.cc b/gpu/command_buffer/client/query_tracker.cc |
index e960d139f9c50200baa0634f3ba9d6d05cd37323..44b25a2ee21ee6463ef28fec314bfe26d6d56efb 100644 |
--- a/gpu/command_buffer/client/query_tracker.cc |
+++ b/gpu/command_buffer/client/query_tracker.cc |
@@ -26,11 +26,8 @@ QuerySyncManager::Bucket::Bucket(QuerySync* sync_mem, |
: syncs(sync_mem), |
shm_id(shm_id), |
base_shm_offset(shm_offset), |
- free_queries(kSyncsPerBucket) { |
- static_assert(kSyncsPerBucket <= USHRT_MAX, |
- "Can't fit kSyncsPerBucket in unsigned short"); |
- for (size_t ii = 0; ii < kSyncsPerBucket; ++ii) |
- free_queries[ii] = ii; |
+ in_use_query_count(0), |
+ next_query_scan_pos(0) { |
} |
QuerySyncManager::Bucket::~Bucket() = default; |
@@ -52,7 +49,7 @@ bool QuerySyncManager::Alloc(QuerySyncManager::QueryInfo* info) { |
DCHECK(info); |
Bucket* bucket = nullptr; |
for (Bucket* bucket_candidate : buckets_) { |
- if (!bucket_candidate->free_queries.empty()) { |
+ if (bucket_candidate->in_use_query_count != kSyncsPerBucket) { |
bucket = bucket_candidate; |
break; |
} |
@@ -70,27 +67,45 @@ bool QuerySyncManager::Alloc(QuerySyncManager::QueryInfo* info) { |
buckets_.push_back(bucket); |
} |
- unsigned short index_in_bucket = bucket->free_queries.back(); |
+ unsigned short index_in_bucket = 0; |
+ size_t start_and_end_i = bucket->next_query_scan_pos; |
+ |
+ // Find a free Query in the bucket by scanning the bitset of free |
+ // flags. Resume the search where we ended last time to avoid |
+ // O(n^2) for the common scenario. |
reveman
2015/05/18 19:58:42
is this really worthwhile? i would prefer if we ke
|
+ size_t i = start_and_end_i; |
+ do { |
+ if (!bucket->in_use_queries[i]) { |
+ index_in_bucket = i; |
+ bucket->next_query_scan_pos = i; |
+ break; |
+ } |
+ i = (i + 1) % kSyncsPerBucket; |
+ } while (i != start_and_end_i); |
+ |
uint32 shm_offset = |
bucket->base_shm_offset + index_in_bucket * sizeof(QuerySync); |
QuerySync* sync = bucket->syncs + index_in_bucket; |
*info = QueryInfo(bucket, bucket->shm_id, shm_offset, sync); |
info->sync->Reset(); |
- bucket->free_queries.pop_back(); |
+ bucket->in_use_queries[index_in_bucket] = true; |
+ bucket->in_use_query_count++; |
return true; |
} |
void QuerySyncManager::Free(const QuerySyncManager::QueryInfo& info) { |
- DCHECK(info.bucket->free_queries.size() < kSyncsPerBucket); |
+ DCHECK(info.bucket->in_use_query_count > 0); |
unsigned short index_in_bucket = info.sync - info.bucket->syncs; |
- info.bucket->free_queries.push_back(index_in_bucket); |
+ DCHECK(info.bucket->in_use_queries[index_in_bucket] == true); |
+ info.bucket->in_use_queries[index_in_bucket] = false; |
+ info.bucket->in_use_query_count--; |
} |
void QuerySyncManager::Shrink() { |
std::deque<Bucket*> new_buckets; |
while (!buckets_.empty()) { |
Bucket* bucket = buckets_.front(); |
- if (bucket->free_queries.size() < kSyncsPerBucket) { |
+ if (bucket->in_use_query_count > 0) { |
new_buckets.push_back(bucket); |
} else { |
mapped_memory_->Free(bucket->syncs); |