diff options
Diffstat (limited to 'src/runtime/mem.go')
| -rw-r--r-- | src/runtime/mem.go | 43 |
1 files changed, 39 insertions, 4 deletions
diff --git a/src/runtime/mem.go b/src/runtime/mem.go index 34391b2eb..438f22ec0 100644 --- a/src/runtime/mem.go +++ b/src/runtime/mem.go @@ -41,8 +41,8 @@ type MemStats struct { OtherSys uint64 // other system allocations // Garbage collector statistics. - NextGC uint64 // next run in HeapAlloc time (bytes) - LastGC uint64 // last run in absolute time (ns) + NextGC uint64 // next collection will happen when HeapAlloc ≥ this amount + LastGC uint64 // end time of last collection (nanoseconds since 1970) PauseTotalNs uint64 PauseNs [256]uint64 // circular buffer of recent GC pause times, most recent at [(NumGC+255)%256] NumGC uint32 @@ -64,9 +64,44 @@ func init() { var memStats MemStats if sizeof_C_MStats != unsafe.Sizeof(memStats) { println(sizeof_C_MStats, unsafe.Sizeof(memStats)) - panic("MStats vs MemStatsType size mismatch") + gothrow("MStats vs MemStatsType size mismatch") } } // ReadMemStats populates m with memory allocator statistics. -func ReadMemStats(m *MemStats) +func ReadMemStats(m *MemStats) { + // Have to acquire worldsema to stop the world, + // because stoptheworld can only be used by + // one goroutine at a time, and there might be + // a pending garbage collection already calling it. + semacquire(&worldsema, false) + gp := getg() + gp.m.gcing = 1 + onM(stoptheworld) + + gp.m.ptrarg[0] = noescape(unsafe.Pointer(m)) + onM(readmemstats_m) + + gp.m.gcing = 0 + gp.m.locks++ + semrelease(&worldsema) + onM(starttheworld) + gp.m.locks-- +} + +// Implementation of runtime/debug.WriteHeapDump +func writeHeapDump(fd uintptr) { + semacquire(&worldsema, false) + gp := getg() + gp.m.gcing = 1 + onM(stoptheworld) + + gp.m.scalararg[0] = fd + onM(writeheapdump_m) + + gp.m.gcing = 0 + gp.m.locks++ + semrelease(&worldsema) + onM(starttheworld) + gp.m.locks-- +} |