5de0a3e9da
In order to open perf events per core, we need to first get the list of core ids available in the system. So I'm adding a function that does that by parsing /proc/cpuinfo. That seems to be the simplest and most portable way to do that. Besides that, I made a few refactors and renames to reflect better that the cpu info that we use in lldb-server comes from procfs. Differential Revision: https://reviews.llvm.org/D124573