Date: Sun, 19 Aug 2012 17:09:52 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
        x86@kernel.org, mmarek@suse.cz, linux-kbuild@vger.kernel.org,
        JBeulich@suse.com, akpm@linux-foundation.org,
        Andi Kleen <ak@linux.intel.com>, Marcelo Tosatti <mtosatti@redhat.com>,
        KVM list <kvm@vger.kernel.org>
Subject: Re: [PATCH 37/74] lto, KVM: Don't assume asm statements end up in the same assembler file
Message-ID: <20120819150951.GR11413@one.firstfloor.org>
References: <1345345030-22211-1-git-send-email-andi@firstfloor.org> <1345345030-22211-38-git-send-email-andi@firstfloor.org> <5030AB00.3090908@redhat.com>
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> The reason we use a local label is so that we the function isn't split
> into two from the profiler's point of view.  See cd2276a795b013d1.

Hmm that commit message is not very enlightening.

The goal was to force a compiler error?

With LTO there is no way to force two functions be in the same assembler
file. The partitioner is always allowed to split.

> 
> One way to fix this is to have a .data variable initialized to point to
> .Lkvm_vmx_return (this can be done from the same asm statement in
> vmx_vcpu_run), and reference that variable in
> vmx_set_constant_host_state().  If no one comes up with a better idea,
> I'll write a patch doing this.

I'm not clear how that is better than my patch.

-andi

-- 
ak@linux.intel.com -- Speaking for myself only.
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