hg: jdk/submit: 8215624: Add parallel heap iteration for jmap ?histo

[paul.hohensee at gmail.com]

Changeset: 179ea0f926ce
Author:    phh
Date:      2020-07-29 11:03 -0700
URL:       https://hg.openjdk.java.net/jdk/submit/rev/179ea0f926ce

8215624: Add parallel heap iteration for jmap ?histo

! src/hotspot/share/services/attachListener.cpp