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Date:   Tue, 14 Apr 2020 23:17:54 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Matt Helsley <mhelsley@vmware.com>,
        Julien Thierry <jthierry@redhat.com>,
        linux-kernel@vger.kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
        Ingo Molnar <mingo@redhat.com>, Miroslav Benes <mbenes@suse.cz>
Subject: Re: [RFC][PATCH 00/36] objtool: Make recordmcount a subcommand
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On Tue, Apr 14, 2020 at 05:05:20PM -0400, Steven Rostedt wrote:
> On Tue, 14 Apr 2020 22:47:29 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Tue, Apr 14, 2020 at 01:09:10PM -0700, Matt Helsley wrote:
> > > I also noticed that, for example, sorttable uses the same ELF code /
> > > patterns as recordmcount -- like the double-include trick. Of course
> > > it operates on a larger scale than per-object-file and so there might
> > > only be code maintenance savings there...  
> > 
> > I'm >< close to having objtool run on vmlinux in the link stage too :-)
> 
> Do we want that? Matters how long that takes.

We do want that, however it is conditional on CONFIG_DEBUG_ENTRY and
does some rather specific validation. On a defconfig based kernel it
takes ~2.5 seconds, significantly more an an allyesconfig.