runtime: update a few "onM"s in comments to say "systemstack"

Commit 656be31 replaced onM with systemstack, but missed updating a
few comments that still referred to onM.  Update these.

Change-Id: I0efb017e9a66ea0adebb6e1da6e518ee11263f69
Reviewed-on: https://go-review.googlesource.com/3664
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go
index 2bbe097d0e50be4c8ec1b70e558f1f5cf3c73bbc..01f02f26bd9665218f5a400be06927005f1089b4 100644 (file)
--- a/src/runtime/mgc.go
+++ b/src/runtime/mgc.go
@@ -1390,7 +1390,7 @@ func gcinit() {
        memstats.next_gc = heapminimum
 }
 
-// Called from malloc.go using onM, stopping and starting the world handled in caller.
+// Called from malloc.go using systemstack, stopping and starting the world handled in caller.
 //go:nowritebarrier
 func gc_m(start_time int64, eagersweep bool) {
        _g_ := getg()
@@ -1419,7 +1419,7 @@ func clearCheckmarks() {
        }
 }
 
-// Called from malloc.go using onM.
+// Called from malloc.go using systemstack.
 // The world is stopped. Rerun the scan and mark phases
 // using the bitMarkedCheck bit instead of the
 // bitMarked bit. If the marking encounters an