diff options
| -rw-r--r-- | absl/strings/internal/cordz_info.cc | 40 | ||||
| -rw-r--r-- | absl/strings/internal/cordz_info_statistics_test.cc | 30 |
2 files changed, 53 insertions, 17 deletions
diff --git a/absl/strings/internal/cordz_info.cc b/absl/strings/internal/cordz_info.cc index 515dfafb..b830c25c 100644 --- a/absl/strings/internal/cordz_info.cc +++ b/absl/strings/internal/cordz_info.cc @@ -33,8 +33,6 @@ namespace absl { ABSL_NAMESPACE_BEGIN namespace cord_internal { -using ::absl::base_internal::SpinLockHolder; - #ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL constexpr size_t CordzInfo::kMaxStackDepth; #endif @@ -79,6 +77,8 @@ class CordRepAnalyzer { // adds the results to `statistics`. Note that node counts and memory sizes // are not initialized, computed values are added to any existing values. void AnalyzeCordRep(const CordRep* rep) { + ABSL_ASSERT(rep != nullptr); + // Process all linear nodes. // As per the class comments, use refcout - 1 on the top level node, as the // top level node is assumed to be referenced only for analysis purposes. @@ -86,7 +86,7 @@ class CordRepAnalyzer { RepRef repref{rep, (refcount > 1) ? refcount - 1 : 1}; // Process the top level CRC node, if present. - if (repref.rep->tag == CRC) { + if (repref.tag() == CRC) { statistics_.node_count++; statistics_.node_counts.crc++; memory_usage_.Add(sizeof(CordRepCrc), repref.refcount); @@ -96,15 +96,17 @@ class CordRepAnalyzer { // Process all top level linear nodes (substrings and flats). repref = CountLinearReps(repref, memory_usage_); - if (repref.rep != nullptr) { - if (repref.rep->tag == RING) { + switch (repref.tag()) { + case CordRepKind::RING: AnalyzeRing(repref); - } else if (repref.rep->tag == BTREE) { + break; + case CordRepKind::BTREE: AnalyzeBtree(repref); - } else { - // We should have either a concat, btree, or ring node if not null. - assert(false); - } + break; + default: + // We should have either a btree or ring node if not null. + ABSL_ASSERT(repref.tag() == CordRepKind::UNUSED_0); + break; } // Adds values to output @@ -122,11 +124,19 @@ class CordRepAnalyzer { const CordRep* rep; size_t refcount; - // Returns a 'child' RepRef which contains the cumulative reference count of - // this instance multiplied by the child's reference count. + // Returns a 'child' RepRef which contains the cumulative reference count + // of this instance multiplied by the child's reference count. Returns a + // nullptr RepRef value with a refcount of 0 if `child` is nullptr. RepRef Child(const CordRep* child) const { + if (child == nullptr) return RepRef{nullptr, 0}; return RepRef{child, refcount * child->refcount.Get()}; } + + // Returns the tag of this rep, or UNUSED_0 if this instance is null + constexpr CordRepKind tag() const { + ABSL_ASSERT(rep == nullptr || rep->tag != CordRepKind::UNUSED_0); + return rep ? static_cast<CordRepKind>(rep->tag) : CordRepKind::UNUSED_0; + } }; // Memory usage values @@ -167,7 +177,7 @@ class CordRepAnalyzer { // buffers where we count children unrounded. RepRef CountLinearReps(RepRef rep, MemoryUsage& memory_usage) { // Consume all substrings - while (rep.rep->tag == SUBSTRING) { + while (rep.tag() == SUBSTRING) { statistics_.node_count++; statistics_.node_counts.substring++; memory_usage.Add(sizeof(CordRepSubstring), rep.refcount); @@ -175,7 +185,7 @@ class CordRepAnalyzer { } // Consume possible FLAT - if (rep.rep->tag >= FLAT) { + if (rep.tag() >= FLAT) { size_t size = rep.rep->flat()->AllocatedSize(); CountFlat(size); memory_usage.Add(size, rep.refcount); @@ -183,7 +193,7 @@ class CordRepAnalyzer { } // Consume possible external - if (rep.rep->tag == EXTERNAL) { + if (rep.tag() == EXTERNAL) { statistics_.node_count++; statistics_.node_counts.external++; size_t size = rep.rep->length + sizeof(CordRepExternalImpl<intptr_t>); diff --git a/absl/strings/internal/cordz_info_statistics_test.cc b/absl/strings/internal/cordz_info_statistics_test.cc index 53d2f2ea..aad3b1ec 100644 --- a/absl/strings/internal/cordz_info_statistics_test.cc +++ b/absl/strings/internal/cordz_info_statistics_test.cc @@ -452,8 +452,7 @@ TEST(CordzInfoStatisticsTest, BtreeNodeShared) { TEST(CordzInfoStatisticsTest, Crc) { RefHelper ref; auto* left = Flat(1000); - auto* crc = - ref.NeedsUnref(CordRepCrc::New(left, crc_internal::CrcCordState())); + auto* crc = ref.NeedsUnref(CordRepCrc::New(left, {})); CordzStatistics expected; expected.size = left->length; @@ -467,6 +466,20 @@ TEST(CordzInfoStatisticsTest, Crc) { EXPECT_THAT(SampleCord(crc), EqStatistics(expected)); } +TEST(CordzInfoStatisticsTest, EmptyCrc) { + RefHelper ref; + auto* crc = ref.NeedsUnref(CordRepCrc::New(nullptr, {})); + + CordzStatistics expected; + expected.size = 0; + expected.estimated_memory_usage = SizeOf(crc); + expected.estimated_fair_share_memory_usage = expected.estimated_memory_usage; + expected.node_count = 1; + expected.node_counts.crc = 1; + + EXPECT_THAT(SampleCord(crc), EqStatistics(expected)); +} + TEST(CordzInfoStatisticsTest, ThreadSafety) { Notification stop; static constexpr int kNumThreads = 8; @@ -497,6 +510,7 @@ TEST(CordzInfoStatisticsTest, ThreadSafety) { InlineData cords[2]; std::minstd_rand gen; std::uniform_int_distribution<int> coin_toss(0, 1); + std::uniform_int_distribution<int> dice_roll(1, 6); while (!stop.HasBeenNotified()) { for (InlineData& cord : cords) { @@ -523,6 +537,18 @@ TEST(CordzInfoStatisticsTest, ThreadSafety) { rep = CordRepBtree::Create(rep); } } + + // Maybe CRC this cord + if (dice_roll(gen) == 6) { + if (dice_roll(gen) == 6) { + // Empty CRC rep + CordRep::Unref(rep); + rep = CordRepCrc::New(nullptr, {}); + } else { + // Regular CRC rep + rep = CordRepCrc::New(rep, {}); + } + } cord.make_tree(rep); // 50/50 sample |