diff options
Diffstat (limited to 'base')
-rw-r--r-- | base/metrics/histogram.cc | 170 | ||||
-rw-r--r-- | base/metrics/histogram.h | 35 | ||||
-rw-r--r-- | base/metrics/histogram_unittest.cc | 25 |
3 files changed, 60 insertions, 170 deletions
diff --git a/base/metrics/histogram.cc b/base/metrics/histogram.cc index 7f935a3..e94cef4 100644 --- a/base/metrics/histogram.cc +++ b/base/metrics/histogram.cc @@ -21,53 +21,6 @@ namespace base { -// Static table of checksums for all possible 8 bit bytes. -const uint32 Histogram::kCrcTable[256] = {0x0, 0x77073096L, 0xee0e612cL, -0x990951baL, 0x76dc419L, 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0xedb8832L, -0x79dcb8a4L, 0xe0d5e91eL, 0x97d2d988L, 0x9b64c2bL, 0x7eb17cbdL, 0xe7b82d07L, -0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, 0x1adad47dL, -0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, 0x646ba8c0L, 0xfd62f97aL, -0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, -0x4c69105eL, 0xd56041e4L, 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, -0xa50ab56bL, 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L, -0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, 0xc8d75180L, -0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, 0xb8bda50fL, 0x2802b89eL, -0x5f058808L, 0xc60cd9b2L, 0xb10be924L, 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, -0xb6662d3dL, 0x76dc4190L, 0x1db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, -0x6b6b51fL, 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0xf00f934L, 0x9609a88eL, -0xe10e9818L, 0x7f6a0dbbL, 0x86d3d2dL, 0x91646c97L, 0xe6635c01L, 0x6b6b51f4L, -0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, 0x1b01a57bL, 0x8208f4c1L, -0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, -0x15da2d49L, 0x8cd37cf3L, 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, -0xd4bb30e2L, 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL, -0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, 0xaa0a4c5fL, -0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, 0xc90c2086L, 0x5768b525L, -0x206f85b3L, 0xb966d409L, 0xce61e49fL, 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, -0xc7d7a8b4L, 0x59b33d17L, 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, -0x9abfb3b6L, 0x3b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x4db2615L, -0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0xd6d6a3eL, 0x7a6a5aa8L, 0xe40ecf0bL, -0x9309ff9dL, 0xa00ae27L, 0x7d079eb1L, 0xf00f9344L, 0x8708a3d2L, 0x1e01f268L, -0x6906c2feL, 0xf762575dL, 0x806567cbL, 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, -0x89d32be0L, 0x10da7a5aL, 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, -0x60b08ed5L, 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L, -0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, 0x36034af6L, -0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, 0x4669be79L, 0xcb61b38cL, -0xbc66831aL, 0x256fd2a0L, 0x5268e236L, 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, -0x5505262fL, 0xc5ba3bbeL, 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, -0xb5d0cf31L, 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL, -0x26d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x5005713L, 0x95bf4a82L, -0xe2b87a14L, 0x7bb12baeL, 0xcb61b38L, 0x92d28e9bL, 0xe5d5be0dL, 0x7cdcefb7L, -0xbdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, -0xf6b9265bL, 0x6fb077e1L, 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, -0x11010b5cL, 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L, -0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, 0x4969474dL, -0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, 0x37d83bf0L, 0xa9bcae53L, -0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, -0x24b4a3a6L, 0xbad03605L, 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, -0xc4614ab8L, 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL, -0x2d02ef8dL, -}; - typedef Histogram::Count Count; // static @@ -85,8 +38,7 @@ scoped_refptr<Histogram> Histogram::FactoryGet(const std::string& name, if (!StatisticsRecorder::FindHistogram(name, &histogram)) { histogram = new Histogram(name, minimum, maximum, bucket_count); - histogram->InitializeBucketRange(); - StatisticsRecorder::Register(&histogram); + StatisticsRecorder::FindHistogram(name, &histogram); } DCHECK_EQ(HISTOGRAM, histogram->histogram_type()); @@ -209,7 +161,7 @@ std::string Histogram::SerializeHistogramInfo(const Histogram& histogram, pickle.WriteInt(histogram.declared_min()); pickle.WriteInt(histogram.declared_max()); pickle.WriteSize(histogram.bucket_count()); - pickle.WriteUInt32(histogram.range_checksum()); + pickle.WriteInt(histogram.range_checksum()); pickle.WriteInt(histogram.histogram_type()); pickle.WriteInt(histogram.flags()); @@ -229,7 +181,7 @@ bool Histogram::DeserializeHistogramInfo(const std::string& histogram_info) { int declared_min; int declared_max; size_t bucket_count; - uint32 range_checksum; + int range_checksum; int histogram_type; int pickle_flags; SampleSet sample; @@ -239,7 +191,7 @@ bool Histogram::DeserializeHistogramInfo(const std::string& histogram_info) { !pickle.ReadInt(&iter, &declared_min) || !pickle.ReadInt(&iter, &declared_max) || !pickle.ReadSize(&iter, &bucket_count) || - !pickle.ReadUInt32(&iter, &range_checksum) || + !pickle.ReadInt(&iter, &range_checksum) || !pickle.ReadInt(&iter, &histogram_type) || !pickle.ReadInt(&iter, &pickle_flags) || !sample.Histogram::SampleSet::Deserialize(&iter, pickle)) { @@ -300,16 +252,18 @@ Histogram::Inconsistencies Histogram::FindCorruption( const SampleSet& snapshot) const { int inconsistencies = NO_INCONSISTENCIES; Sample previous_range = -1; // Bottom range is always 0. + Sample checksum = 0; int64 count = 0; for (size_t index = 0; index < bucket_count(); ++index) { count += snapshot.counts(index); int new_range = ranges(index); + checksum += new_range; if (previous_range >= new_range) inconsistencies |= BUCKET_ORDER_ERROR; previous_range = new_range; } - if (!HasValidRangeChecksum()) + if (checksum != range_checksum_) inconsistencies |= RANGE_CHECKSUM_ERROR; int64 delta64 = snapshot.redundant_count() - count; @@ -374,10 +328,6 @@ bool Histogram::HasConstructorTimeDeltaArguments(TimeDelta minimum, (bucket_count == bucket_count_)); } -bool Histogram::HasValidRangeChecksum() const { - return CalculateRangeChecksum() == range_checksum_; -} - Histogram::Histogram(const std::string& name, Sample minimum, Sample maximum, size_t bucket_count) : histogram_name_(name), @@ -413,6 +363,7 @@ Histogram::~Histogram() { // Just to make sure most derived class did this properly... DCHECK(ValidateBucketRanges()); + DCHECK(HasValidRangeChecksum()); } bool Histogram::PrintEmptyBucket(size_t index) const { @@ -527,14 +478,6 @@ bool Histogram::ValidateBucketRanges() const { return true; } -uint32 Histogram::CalculateRangeChecksum() const { - DCHECK_EQ(ranges_.size(), bucket_count() + 1); - uint32 checksum = static_cast<uint32>(ranges_.size()); // Seed checksum. - for (size_t index = 0; index < bucket_count(); ++index) - checksum = Crc32(checksum, ranges(index)); - return checksum; -} - void Histogram::Initialize() { sample_.Resize(*this); if (declared_min_ < 1) @@ -548,42 +491,22 @@ void Histogram::Initialize() { DCHECK_LE(bucket_count_, maximal_bucket_count); DCHECK_EQ(0, ranges_[0]); ranges_[bucket_count_] = kSampleType_MAX; + InitializeBucketRange(); + DCHECK(ValidateBucketRanges()); + StatisticsRecorder::Register(this); } -// We generate the CRC-32 using the low order bits to select whether to XOR in -// the reversed polynomial 0xedb88320L. This is nice and simple, and allows us -// to keep the quotient in a uint32. Since we're not concerned about the nature -// of corruptions (i.e., we don't care about bit sequencing, since we are -// handling memory changes, which are more grotesque) so we don't bother to -// get the CRC correct for big-endian vs little-ending calculations. All we -// need is a nice hash, that tends to depend on all the bits of the sample, with -// very little chance of changes in one place impacting changes in another -// place. -uint32 Histogram::Crc32(uint32 sum, Histogram::Sample range) { - const bool kUseRealCrc = true; // TODO(jar): Switch to false and watch stats. - if (kUseRealCrc) { - union { - Histogram::Sample range; - unsigned char bytes[sizeof(Histogram::Sample)]; - } converter; - converter.range = range; - for (size_t i = 0; i < sizeof(converter); ++i) - sum = kCrcTable[(sum & 0xff) ^ converter.bytes[i]] ^ (sum >> 8); - } else { - // Use hash techniques provided in ReallyFastHash, except we don't care - // about "avalanching" (which would worsten the hash, and add collisions), - // and we don't care about edge cases since we have an even number of bytes. - union { - Histogram::Sample range; - uint16 ints[sizeof(Histogram::Sample) / 2]; - } converter; - DCHECK_EQ(sizeof(Histogram::Sample), sizeof(converter)); - converter.range = range; - sum += converter.ints[0]; - sum = (sum << 16) ^ sum ^ (static_cast<uint32>(converter.ints[1]) << 11); - sum += sum >> 11; +bool Histogram::HasValidRangeChecksum() const { + return CalculateRangeChecksum() == range_checksum_; +} + +Histogram::Sample Histogram::CalculateRangeChecksum() const { + DCHECK_EQ(ranges_.size(), bucket_count() + 1); + Sample checksum = 0; + for (size_t index = 0; index < bucket_count(); ++index) { + checksum += ranges(index); } - return sum; + return checksum; } //------------------------------------------------------------------------------ @@ -787,11 +710,8 @@ scoped_refptr<Histogram> LinearHistogram::FactoryGet(const std::string& name, maximum = kSampleType_MAX - 1; if (!StatisticsRecorder::FindHistogram(name, &histogram)) { - LinearHistogram* linear_histogram = - new LinearHistogram(name, minimum, maximum, bucket_count); - linear_histogram->InitializeBucketRange(); - histogram = linear_histogram; - StatisticsRecorder::Register(&histogram); + histogram = new LinearHistogram(name, minimum, maximum, bucket_count); + StatisticsRecorder::FindHistogram(name, &histogram); } DCHECK_EQ(LINEAR_HISTOGRAM, histogram->histogram_type()); @@ -826,6 +746,8 @@ LinearHistogram::LinearHistogram(const std::string& name, Sample maximum, size_t bucket_count) : Histogram(name, minimum >= 1 ? minimum : 1, maximum, bucket_count) { + InitializeBucketRange(); + DCHECK(ValidateBucketRanges()); } LinearHistogram::LinearHistogram(const std::string& name, @@ -835,6 +757,9 @@ LinearHistogram::LinearHistogram(const std::string& name, : Histogram(name, minimum >= TimeDelta::FromMilliseconds(1) ? minimum : TimeDelta::FromMilliseconds(1), maximum, bucket_count) { + // Do a "better" (different) job at init than a base classes did... + InitializeBucketRange(); + DCHECK(ValidateBucketRanges()); } void LinearHistogram::InitializeBucketRange() { @@ -880,10 +805,8 @@ scoped_refptr<Histogram> BooleanHistogram::FactoryGet(const std::string& name, scoped_refptr<Histogram> histogram(NULL); if (!StatisticsRecorder::FindHistogram(name, &histogram)) { - BooleanHistogram* boolean_histogram = new BooleanHistogram(name); - boolean_histogram->InitializeBucketRange(); - histogram = boolean_histogram; - StatisticsRecorder::Register(&histogram); + histogram = new BooleanHistogram(name); + StatisticsRecorder::FindHistogram(name, &histogram); } DCHECK_EQ(BOOLEAN_HISTOGRAM, histogram->histogram_type()); @@ -927,10 +850,8 @@ scoped_refptr<Histogram> CustomHistogram::FactoryGet( DCHECK_LT(ranges.back(), kSampleType_MAX); if (!StatisticsRecorder::FindHistogram(name, &histogram)) { - CustomHistogram* custom_histogram = new CustomHistogram(name, ranges); - custom_histogram->InitializedCustomBucketRange(ranges); - histogram = custom_histogram; - StatisticsRecorder::Register(&histogram); + histogram = new CustomHistogram(name, ranges); + StatisticsRecorder::FindHistogram(name, &histogram); } DCHECK_EQ(histogram->histogram_type(), CUSTOM_HISTOGRAM); @@ -950,15 +871,16 @@ CustomHistogram::CustomHistogram(const std::string& name, custom_ranges.size()) { DCHECK_GT(custom_ranges.size(), 1u); DCHECK_EQ(custom_ranges[0], 0); + ranges_vector_ = &custom_ranges; + InitializeBucketRange(); + ranges_vector_ = NULL; + DCHECK(ValidateBucketRanges()); } -void CustomHistogram::InitializedCustomBucketRange( - const std::vector<Sample>& custom_ranges) { - DCHECK_GT(custom_ranges.size(), 1u); - DCHECK_EQ(custom_ranges[0], 0); - DCHECK_LE(custom_ranges.size(), bucket_count()); - for (size_t index = 0; index < custom_ranges.size(); ++index) - SetBucketRange(index, custom_ranges[index]); +void CustomHistogram::InitializeBucketRange() { + DCHECK_LE(ranges_vector_->size(), bucket_count()); + for (size_t index = 0; index < ranges_vector_->size(); ++index) + SetBucketRange(index, (*ranges_vector_)[index]); ResetRangeChecksum(); } @@ -1023,20 +945,16 @@ bool StatisticsRecorder::IsActive() { // was passed to us, decremented it when we returned, and the instance would be // destroyed before assignment (when value was returned by new). // static -void StatisticsRecorder::Register(scoped_refptr<Histogram>* histogram) { - DCHECK((*histogram)->HasValidRangeChecksum()); +void StatisticsRecorder::Register(Histogram* histogram) { if (lock_ == NULL) return; base::AutoLock auto_lock(*lock_); if (!histograms_) return; - const std::string name = (*histogram)->histogram_name(); - HistogramMap::iterator it = histograms_->find(name); + const std::string name = histogram->histogram_name(); // Avoid overwriting a previous registration. - if (histograms_->end() == it) - (*histograms_)[name] = *histogram; - else - *histogram = it->second; + if (histograms_->end() == histograms_->find(name)) + (*histograms_)[name] = histogram; } // static diff --git a/base/metrics/histogram.h b/base/metrics/histogram.h index 94f219b..372dae5 100644 --- a/base/metrics/histogram.h +++ b/base/metrics/histogram.h @@ -411,7 +411,7 @@ class Histogram : public base::RefCountedThreadSafe<Histogram> { Sample declared_min() const { return declared_min_; } Sample declared_max() const { return declared_max_; } virtual Sample ranges(size_t i) const; - uint32 range_checksum() const { return range_checksum_; } + Sample range_checksum() const { return range_checksum_; } virtual size_t bucket_count() const; // Snapshot the current complete set of sample data. // Override with atomic/locked snapshot if needed. @@ -423,8 +423,6 @@ class Histogram : public base::RefCountedThreadSafe<Histogram> { virtual bool HasConstructorTimeDeltaArguments(TimeDelta minimum, TimeDelta maximum, size_t bucket_count); - // Return true iff the range_checksum_ matches current ranges_ vector. - bool HasValidRangeChecksum() const; protected: friend class base::RefCountedThreadSafe<Histogram>; @@ -471,20 +469,18 @@ class Histogram : public base::RefCountedThreadSafe<Histogram> { // values relate properly to the declared_min_ and declared_max_).. bool ValidateBucketRanges() const; - virtual uint32 CalculateRangeChecksum() const; - private: // Allow tests to corrupt our innards for testing purposes. FRIEND_TEST(HistogramTest, CorruptBucketBounds); FRIEND_TEST(HistogramTest, CorruptSampleCounts); - FRIEND_TEST(HistogramTest, Crc32SampleHash); - FRIEND_TEST(HistogramTest, Crc32TableTest); // Post constructor initialization. void Initialize(); - // Checksum function for accumulating range values into a checksum. - static uint32 Crc32(uint32 sum, Sample range); + // Return true iff the range_checksum_ matches current ranges_ vector. + bool HasValidRangeChecksum() const; + + Sample CalculateRangeChecksum() const; //---------------------------------------------------------------------------- // Helpers for emitting Ascii graphic. Each method appends data to output. @@ -512,9 +508,6 @@ class Histogram : public base::RefCountedThreadSafe<Histogram> { std::string* output) const; //---------------------------------------------------------------------------- - // Table for generating Crc32 values. - static const uint32 kCrcTable[256]; - //---------------------------------------------------------------------------- // Invariant values set at/near construction time // ASCII version of original name given to the constructor. All identically @@ -533,10 +526,10 @@ class Histogram : public base::RefCountedThreadSafe<Histogram> { // The dimension of ranges_ is bucket_count + 1. Ranges ranges_; - // For redundancy, we store a checksum of all the sample ranges when ranges - // are generated. If ever there is ever a difference, then the histogram must + // For redundancy, we store the sum of all the sample ranges when ranges are + // generated. If ever there is ever a difference, then the histogram must // have been corrupted. - uint32 range_checksum_; + Sample range_checksum_; // Finally, provide the state that changes with the addition of each new // sample. @@ -632,9 +625,13 @@ class CustomHistogram : public Histogram { const std::vector<Sample>& custom_ranges); // Initialize ranges_ mapping. - void InitializedCustomBucketRange(const std::vector<Sample>& custom_ranges); + virtual void InitializeBucketRange(); virtual double GetBucketSize(Count current, size_t i) const; + private: + // Temporary pointer used during construction/initialization, and then NULLed. + const std::vector<Sample>* ranges_vector_; + DISALLOW_COPY_AND_ASSIGN(CustomHistogram); }; @@ -654,10 +651,8 @@ class StatisticsRecorder { // Find out if histograms can now be registered into our list. static bool IsActive(); - // Register, or add a new histogram to the collection of statistics. If an - // identically named histogram is already registered, then the argument - // |histogram| will be replaced by the previously registered value. - static void Register(scoped_refptr<Histogram>* histogram); + // Register, or add a new histogram to the collection of statistics. + static void Register(Histogram* histogram); // Methods for printing histograms. Only histograms which have query as // a substring are written to output (an empty string will process all diff --git a/base/metrics/histogram_unittest.cc b/base/metrics/histogram_unittest.cc index afa69a6..b9c51ad 100644 --- a/base/metrics/histogram_unittest.cc +++ b/base/metrics/histogram_unittest.cc @@ -348,8 +348,7 @@ TEST(HistogramTest, CorruptBucketBounds) { EXPECT_EQ(0, histogram->FindCorruption(snapshot)); // No default corruption. std::swap(histogram->ranges_[1], histogram->ranges_[2]); - EXPECT_EQ(Histogram::BUCKET_ORDER_ERROR | Histogram::RANGE_CHECKSUM_ERROR, - histogram->FindCorruption(snapshot)); + EXPECT_EQ(Histogram::BUCKET_ORDER_ERROR, histogram->FindCorruption(snapshot)); std::swap(histogram->ranges_[1], histogram->ranges_[2]); EXPECT_EQ(0, histogram->FindCorruption(snapshot)); @@ -358,30 +357,8 @@ TEST(HistogramTest, CorruptBucketBounds) { EXPECT_EQ(Histogram::RANGE_CHECKSUM_ERROR, histogram->FindCorruption(snapshot)); - // Show that two simple changes don't offset each other - --histogram->ranges_[4]; - EXPECT_EQ(Histogram::RANGE_CHECKSUM_ERROR, - histogram->FindCorruption(snapshot)); - // Repair histogram so that destructor won't DCHECK(). --histogram->ranges_[3]; - ++histogram->ranges_[4]; -} - -// Table was generated similarly to sample code for CRC-32 given on: -// http://www.w3.org/TR/PNG/#D-CRCAppendix. -TEST(HistogramTest, Crc32TableTest) { - for (int i = 0; i < 256; ++i) { - uint32 checksum = i; - for (int j = 0; j < 8; ++j) { - const uint32 kReversedPolynomial = 0xedb88320L; - if (checksum & 1) - checksum = kReversedPolynomial ^ (checksum >> 1); - else - checksum >>= 1; - } - EXPECT_EQ(Histogram::kCrcTable[i], checksum); - } } } // namespace base |