runtime: fix SetBlockProfileRate It doughtily misses all possible corner cases. In particular on machines with <1GHz processors, SetBlockProfileRate(1) disables profiling. Fixes issue 6114.
runtime: fix SetBlockProfileRate
It doughtily misses all possible corner cases.
In particular on machines with <1GHz processors,
SetBlockProfileRate(1) disables profiling.
Fixes issue 6114.

R=golang-dev, bradfitz, rsc
CC=golang-dev
https://codereview.appspot.com/12936043

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang