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Date:   Mon, 20 Apr 2020 10:27:28 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>
Subject: Re: [GIT pull] perf/urgent for 5.7-rc2
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On Mon, Apr 20, 2020 at 09:48:45AM +0200, Ingo Molnar wrote:
> Fortunately, much of what objtool does against vmlinux.o can be 
> parallelized in a rather straightforward fashion I believe, if we build 
> with -ffunction-sections.

So that FGKASLR is going to get us -ffunction-sections, but
parallelizing objtool isn't going to be trivial, it's data structures
aren't really build for that, esp. decode_instructions() which actively
generates data.

Still, it's probably doable.