Re: [PATCH 3/6] x86: Allow the user not to build hw_breakpoints

From: Frederic Weisbecker
Date: Tue May 03 2011 - 19:12:50 EST


On Tue, May 03, 2011 at 08:35:53AM -0700, H. Peter Anvin wrote:
> On 04/27/2011 12:50 PM, Frederic Weisbecker wrote:
> > On Wed, Apr 27, 2011 at 11:54:17AM -0700, H. Peter Anvin wrote:
> >> Why do you have to be able to disable breakpoints to disable perf? That seems seriously backwards, especially since we had breakpoints long before perf...
> >
> > That started when we implemented breakpoints as counters. Then we realized that
> > ptrace had its own scheduling that was somehow duplicating what perf was doing.
> > So we have finally unified that under perf. The good point is that archs don't need
> > to care much about ptrace breakpoints tracking, just the interface.
> >
> > But yeah the bad point is that dependency.
>
> It really is very bad... without breakpoints, you lose almost all
> debugging support.

Right, so it should be fine for embedded environment to disable breakpoints.
It depends on CONFIG_EXPERT now.
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