runtime: in exitsyscall, avoid confusing garbage collector
R=r
CC=golang-dev
https://golang.org/cl/178046
diff --git a/src/pkg/runtime/proc.c b/src/pkg/runtime/proc.c
index f04cb66..e81089b 100644
--- a/src/pkg/runtime/proc.c
+++ b/src/pkg/runtime/proc.c
@@ -566,14 +566,19 @@
unlock(&sched);
return;
}
- g->status = Grunning;
sched.msyscall--;
sched.mcpu++;
// Fast path - if there's room for this m, we're done.
if(sched.mcpu <= sched.mcpumax) {
+ g->status = Grunning;
unlock(&sched);
return;
}
+ // Tell scheduler to put g back on the run queue:
+ // mostly equivalent to g->status = Grunning,
+ // but keeps the garbage collector from thinking
+ // that g is running right now, which it's not.
+ g->readyonstop = 1;
unlock(&sched);
// Slow path - all the cpus are taken.
