diff options
Diffstat (limited to 'src/runtime/metrics.go')
| -rw-r--r-- | src/runtime/metrics.go | 45 |
1 files changed, 31 insertions, 14 deletions
diff --git a/src/runtime/metrics.go b/src/runtime/metrics.go index ba0a920a5d..922dd2f814 100644 --- a/src/runtime/metrics.go +++ b/src/runtime/metrics.go @@ -12,9 +12,12 @@ import ( ) var ( - // metrics is a map of runtime/metrics keys to - // data used by the runtime to sample each metric's - // value. + // metrics is a map of runtime/metrics keys to data used by the runtime + // to sample each metric's value. metricsInit indicates it has been + // initialized. + // + // These fields are protected by metricsSema which should be + // locked/unlocked with metricsLock() / metricsUnlock(). metricsSema uint32 = 1 metricsInit bool metrics map[string]metricData @@ -34,6 +37,23 @@ type metricData struct { compute func(in *statAggregate, out *metricValue) } +func metricsLock() { + // Acquire the metricsSema but with handoff. Operations are typically + // expensive enough that queueing up goroutines and handing off between + // them will be noticeably better-behaved. + semacquire1(&metricsSema, true, 0, 0) + if raceenabled { + raceacquire(unsafe.Pointer(&metricsSema)) + } +} + +func metricsUnlock() { + if raceenabled { + racerelease(unsafe.Pointer(&metricsSema)) + } + semrelease(&metricsSema) +} + // initMetrics initializes the metrics map if it hasn't been yet. // // metricsSema must be held. @@ -388,13 +408,13 @@ func (a *heapStatsAggregate) compute() { memstats.heapStats.read(&a.heapStatsDelta) // Calculate derived stats. - a.totalAllocs = uint64(a.largeAllocCount) - a.totalFrees = uint64(a.largeFreeCount) - a.totalAllocated = uint64(a.largeAlloc) - a.totalFreed = uint64(a.largeFree) + a.totalAllocs = a.largeAllocCount + a.totalFrees = a.largeFreeCount + a.totalAllocated = a.largeAlloc + a.totalFreed = a.largeFree for i := range a.smallAllocCount { - na := uint64(a.smallAllocCount[i]) - nf := uint64(a.smallFreeCount[i]) + na := a.smallAllocCount[i] + nf := a.smallFreeCount[i] a.totalAllocs += na a.totalFrees += nf a.totalAllocated += na * uint64(class_to_size[i]) @@ -546,10 +566,7 @@ func readMetrics(samplesp unsafe.Pointer, len int, cap int) { sl := slice{samplesp, len, cap} samples := *(*[]metricSample)(unsafe.Pointer(&sl)) - // Acquire the metricsSema but with handoff. This operation - // is expensive enough that queueing up goroutines and handing - // off between them will be noticeably better-behaved. - semacquire1(&metricsSema, true, 0, 0) + metricsLock() // Ensure the map is initialized. initMetrics() @@ -573,5 +590,5 @@ func readMetrics(samplesp unsafe.Pointer, len int, cap int) { data.compute(&agg, &sample.value) } - semrelease(&metricsSema) + metricsUnlock() } |