runtime: fix lock rank for work.spanSPMCs.lock

Currently this lock is treated like a leaf lock, but it's not one. It
can acquire the globalAlloc lock via fixalloc and persistentalloc.

This means we need to figure out where it can be acquired. In general,
it can be acquired by any write barrier, which is already incredibly
broad. AFAICT, it can't be acquired directly otherwise, except when
destroying a spanSPMC during procresize, in which case we'll be holding
sched.lock.

Fixes #75916.

Change-Id: I2da1f5b82c750bf4e8d6a8a562046b9a17fd44be
Reviewed-on: https://go-review.googlesource.com/c/go/+/717500
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
This commit is contained in:
Michael Anthony Knyszek 2025-11-03 21:40:33 +00:00 committed by Michael Knyszek
parent bc5ffe5c79
commit 052c192a4c
3 changed files with 10 additions and 3 deletions

View file

@ -71,6 +71,7 @@ const (
// WB
lockRankWbufSpans
lockRankXRegAlloc
lockRankSpanSPMCs
lockRankMheap
lockRankMheapSpecial
lockRankGlobalAlloc
@ -145,6 +146,7 @@ var lockNames = []string{
lockRankHchanLeaf: "hchanLeaf",
lockRankWbufSpans: "wbufSpans",
lockRankXRegAlloc: "xRegAlloc",
lockRankSpanSPMCs: "spanSPMCs",
lockRankMheap: "mheap",
lockRankMheapSpecial: "mheapSpecial",
lockRankGlobalAlloc: "globalAlloc",
@ -231,9 +233,10 @@ var lockPartialOrder [][]lockRank = [][]lockRank{
lockRankHchanLeaf: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankHchanLeaf},
lockRankWbufSpans: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan},
lockRankXRegAlloc: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankTimerSend, lockRankCpuprof, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched},
lockRankSpanSPMCs: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan},
lockRankMheap: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans},
lockRankMheapSpecial: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans, lockRankMheap},
lockRankGlobalAlloc: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans, lockRankXRegAlloc, lockRankMheap, lockRankMheapSpecial},
lockRankGlobalAlloc: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans, lockRankXRegAlloc, lockRankSpanSPMCs, lockRankMheap, lockRankMheapSpecial},
lockRankTrace: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans, lockRankMheap},
lockRankTraceStackTab: {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankComputeMaxProcs, lockRankUpdateMaxProcsG, lockRankDefer, lockRankSweepWaiters, lockRankAssistQueue, lockRankStrongFromWeakQueue, lockRankCleanupQueue, lockRankSweep, lockRankTestR, lockRankVgetrandom, lockRankTimerSend, lockRankExecW, lockRankCpuprof, lockRankPollCache, lockRankPollDesc, lockRankWakeableSleep, lockRankHchan, lockRankAllocmR, lockRankExecR, lockRankSched, lockRankAllg, lockRankAllp, lockRankNotifyList, lockRankSudog, lockRankTimers, lockRankTimer, lockRankNetpollInit, lockRankRoot, lockRankItab, lockRankReflectOffs, lockRankSynctest, lockRankUserArenaState, lockRankTraceBuf, lockRankTraceStrings, lockRankFin, lockRankSpanSetSpine, lockRankMspanSpecial, lockRankGcBitsArenas, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankWbufSpans, lockRankMheap, lockRankTrace},
lockRankPanic: {},

View file

@ -199,6 +199,7 @@ func gcinit() {
lockInit(&work.assistQueue.lock, lockRankAssistQueue)
lockInit(&work.strongFromWeak.lock, lockRankStrongFromWeakQueue)
lockInit(&work.wbufSpans.lock, lockRankWbufSpans)
lockInit(&work.spanSPMCs.lock, lockRankSpanSPMCs)
lockInit(&gcCleanups.lock, lockRankCleanupQueue)
}
@ -352,7 +353,7 @@ type workType struct {
//
// Only used if goexperiment.GreenTeaGC.
spanSPMCs struct {
lock mutex // no lock rank because it's a leaf lock (see mklockrank.go).
lock mutex
all *spanSPMC
}

View file

@ -196,6 +196,9 @@ defer,
# xRegState allocator
sched < xRegAlloc;
# spanSPMCs allocator and list
WB, sched < spanSPMCs;
# Span allocator
stackLarge,
stackpool,
@ -209,7 +212,7 @@ stackLarge,
# Pinner bits might be freed by the span allocator.
mheap, mspanSpecial < mheapSpecial;
# Fixallocs
mheap, mheapSpecial, xRegAlloc < globalAlloc;
mheap, mheapSpecial, xRegAlloc, spanSPMCs < globalAlloc;
# Execution tracer events (with a P)
hchan,