From: Michael Anthony Knyszek <mknyszek@google.com>
Date: Tue, 10 Nov 2020 15:32:59 +0000 (+0000)
Subject: runtime: add lock rank partial order edge sweep -> mspanSpecial
X-Git-Tag: go1.16beta1~262
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=c68745b130;p=gostls13.git

runtime: add lock rank partial order edge sweep -> mspanSpecial

This change adds a missing partial order edge. The edge captures the
case where the background sweeper handles some specials (i.e. finalizers
or memory profile sampling) and is otherwise correct.

Fixes #42472.

Change-Id: Ic45f6cc1635fd3d6bc6c91ff6f64d436088cef33
Reviewed-on: https://go-review.googlesource.com/c/go/+/268857
Trust: Michael Knyszek <mknyszek@google.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
---

diff --git a/src/runtime/lockrank.go b/src/runtime/lockrank.go
index 0a52e8ed3d..5fb7f08c44 100644
--- a/src/runtime/lockrank.go
+++ b/src/runtime/lockrank.go
@@ -213,7 +213,7 @@ var lockPartialOrder [][]lockRank = [][]lockRank{
 	lockRankNotifyList:    {},
 	lockRankTraceBuf:      {lockRankSysmon, lockRankScavenge},
 	lockRankTraceStrings:  {lockRankTraceBuf},
-	lockRankMspanSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankNotifyList, lockRankTraceBuf, lockRankTraceStrings},
+	lockRankMspanSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankNotifyList, lockRankTraceBuf, lockRankTraceStrings},
 	lockRankProf:          {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankNotifyList, lockRankTraceBuf, lockRankTraceStrings, lockRankHchan},
 	lockRankGcBitsArenas:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSched, lockRankAllg, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankNotifyList, lockRankTraceBuf, lockRankTraceStrings, lockRankHchan},
 	lockRankRoot:          {},