runtime: fix some out-of-date comments

bgMarkCount no longer exists.

Change-Id: I3aa406fdccfca659814da311229afbae55af8304
Reviewed-on: https://go-review.googlesource.com/9297
Reviewed-by: Rick Hudson <rlh@golang.org>

diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go
index 3b424818632503ea0f6db6eda0dda1d73b76b6da..db7f859ddfe90fc3a5b7140e468b463d5925b92f 100644 (file)
--- a/src/runtime/mgc.go
+++ b/src/runtime/mgc.go
@@ -485,8 +485,7 @@ func (c *gcControllerState) findRunnable(_p_ *p) *g {
                // No work to be done right now. This can happen at
                // the end of the mark phase when there are still
                // assists tapering off. Don't bother running
-               // background mark because it'll just return and
-               // bgMarkCount might hover above zero.
+               // background mark because it'll just return immediately.
                return nil
        }
 
@@ -515,7 +514,7 @@ func (c *gcControllerState) findRunnable(_p_ *p) *g {
                // slice, would it be under the utilization goal?
                //
                // TODO(austin): We could fast path this and basically
-               // eliminate contention on c.bgMarkCount by
+               // eliminate contention on c.fractionalMarkWorkersNeeded by
                // precomputing the minimum time at which it's worth
                // next scheduling the fractional worker. Then Ps
                // don't have to fight in the window where we've