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Date:   Thu, 7 Mar 2019 18:38:10 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Anvin <hpa@zytor.com>,
        Julien Thierry <julien.thierry@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Ingo Molnar <mingo@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        James Morse <james.morse@arm.com>, valentin.schneider@arm.com,
        Brian Gerst <brgerst@gmail.com>,
        Andrew Lutomirski <luto@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH 00/20] objtool: UACCESS validation v3
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On Thu, Mar 07, 2019 at 11:17:09AM -0600, Josh Poimboeuf wrote:
> On Thu, Mar 07, 2019 at 09:00:49AM -0800, Linus Torvalds wrote:
> > But that macro really is the macro from hell regardless.
> > 
> > Do people really use CONFIG_PROFILE_ALL_BRANCHES?
> 
> IIRC, Steven runs it once a year or so...

That's TRACE_BRANCH_PROFILING; PROFILE_ALL_BRANCHES I don't know, that
mostly just gets in the way I think.

Also; it seems to me that something PT, or maybe even simply:

  perf -e branches -e branch-misses

would get you similar or sufficient information.