commit 14c12d61ad2ef07990ab3f298495c5f862723b30
author Ryan Savitski <rsavitski@google.com> Tue Jan 08 22:38:53 2019 +0000
committer Ryan Savitski <rsavitski@google.com> Tue Jan 08 22:38:53 2019 +0000
tree 83653217b7ce5315d8d15999a247f7912774d61c
parent 4f115007206c8b8cccf48cafa663c1653986a68f

heapprofd: fork model mode-select groundwork

This patch introduces:
 * the flags necessary for heapprofd to start as a "child" for a given
   process.
 * logic to fork-exec heapprofd in malloc hook initialization.

If using the fork model, both the hook & private heapprofd exit without
doing much for now.

On user builds (based on "ro.build.type" sysprop), we always select the
fork model. On userdebug/eng, we consult a secondary sysprop,
"heapprofd.userdebug.mode", and use fork if it's set to "fork".

Aside: note that I'm proposing userdebug mode-selection to be global in
nature (not per-datasource).

Bug: 120185246
Change-Id: I9afbc725a2a626c40a0af358536e001a280e53a9