diff options
Diffstat (limited to 'libgo/go/runtime/mgc.go')
| -rw-r--r-- | libgo/go/runtime/mgc.go | 43 |
1 files changed, 34 insertions, 9 deletions
diff --git a/libgo/go/runtime/mgc.go b/libgo/go/runtime/mgc.go index 24043cf..9dd7bff 100644 --- a/libgo/go/runtime/mgc.go +++ b/libgo/go/runtime/mgc.go @@ -191,6 +191,9 @@ func gcinit() { work.startSema = 1 work.markDoneSema = 1 + lockInit(&work.sweepWaiters.lock, lockRankSweepWaiters) + lockInit(&work.assistQueue.lock, lockRankAssistQueue) + lockInit(&work.wbufSpans.lock, lockRankWbufSpans) } func readgogc() int32 { @@ -235,8 +238,6 @@ func setGCPercent(in int32) (out int32) { gcSetTriggerRatio(memstats.triggerRatio) unlock(&mheap_.lock) }) - // Pacing changed, so the scavenger should be awoken. - wakeScavenger() // If we just disabled GC, wait for any concurrent GC mark to // finish so we always return with no GC running. @@ -1279,6 +1280,7 @@ func gcStart(trigger gcTrigger) { } // Ok, we're doing it! Stop everybody else + semacquire(&gcsema) semacquire(&worldsema) if trace.enabled { @@ -1318,6 +1320,7 @@ func gcStart(trigger gcTrigger) { systemstack(func() { finishsweep_m() }) + // clearpools before we start the GC. If we wait they memory will not be // reclaimed until the next GC cycle. clearpools() @@ -1371,15 +1374,26 @@ func gcStart(trigger gcTrigger) { // the world. gcController.markStartTime = now + // In STW mode, we could block the instant systemstack + // returns, so make sure we're not preemptible. + mp = acquirem() + // Concurrent mark. systemstack(func() { now = startTheWorldWithSema(trace.enabled) work.pauseNS += now - work.pauseStart work.tMark = now }) - // In STW mode, we could block the instant systemstack - // returns, so don't do anything important here. Make sure we - // block rather than returning to user code. + + // Release the world sema before Gosched() in STW mode + // because we will need to reacquire it later but before + // this goroutine becomes runnable again, and we could + // self-deadlock otherwise. + semrelease(&worldsema) + releasem(mp) + + // Make sure we block instead of returning to user code + // in STW mode. if mode != gcBackgroundMode { Gosched() } @@ -1446,6 +1460,10 @@ top: return } + // forEachP needs worldsema to execute, and we'll need it to + // stop the world later, so acquire worldsema now. + semacquire(&worldsema) + // Flush all local buffers and collect flushedWork flags. gcMarkDoneFlushed = 0 systemstack(func() { @@ -1506,6 +1524,7 @@ top: // work to do. Keep going. It's possible the // transition condition became true again during the // ragged barrier, so re-check it. + semrelease(&worldsema) goto top } @@ -1582,6 +1601,7 @@ top: now := startTheWorldWithSema(true) work.pauseNS += now - work.pauseStart }) + semrelease(&worldsema) goto top } } @@ -1687,9 +1707,6 @@ func gcMarkTermination(nextTriggerRatio float64) { // Update GC trigger and pacing for the next cycle. gcSetTriggerRatio(nextTriggerRatio) - // Pacing changed, so the scavenger should be awoken. - wakeScavenger() - // Update timing memstats now := nanotime() sec, nsec, _ := time_now() @@ -1796,6 +1813,7 @@ func gcMarkTermination(nextTriggerRatio float64) { } semrelease(&worldsema) + semrelease(&gcsema) // Careful: another GC cycle may start now. releasem(mp) @@ -2121,6 +2139,9 @@ func gcMark(start_time int64) { // gcSweep must be called on the system stack because it acquires the heap // lock. See mheap for details. +// +// The world must be stopped. +// //go:systemstack func gcSweep(mode gcMode) { if gcphase != _GCoff { @@ -2130,7 +2151,7 @@ func gcSweep(mode gcMode) { lock(&mheap_.lock) mheap_.sweepgen += 2 mheap_.sweepdone = 0 - if mheap_.sweepSpans[mheap_.sweepgen/2%2].index != 0 { + if !go115NewMCentralImpl && mheap_.sweepSpans[mheap_.sweepgen/2%2].index != 0 { // We should have drained this list during the last // sweep phase. We certainly need to start this phase // with an empty swept list. @@ -2142,6 +2163,10 @@ func gcSweep(mode gcMode) { mheap_.reclaimCredit = 0 unlock(&mheap_.lock) + if go115NewMCentralImpl { + sweep.centralIndex.clear() + } + if !_ConcurrentSweep || mode == gcForceBlockMode { // Special case synchronous sweep. // Record that no proportional sweeping has to happen. |