Ben Gamari authored Jan 22, 2016 and Ben Gamari committed Jan 22, 2016

Trac #9105 notes significant CPU usage by an otherwise idle process when
compiled with profiling. The reason for this is that we keep the tick
timer active in the profiling RTS even if profiling wasn't requested at
runtime.

If the user requests any sort of profiling then we need to keep the
timer active to ensure that samples are collected.

Test Plan: Validate, check CPU usage, ensure profiling still works

Reviewers: simonmar, austin

Reviewed By: simonmar, austin

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1822

GHC Trac Issues: #9105