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Subject: Re: [PATCH 14/17] KVM: monolithic: x86: inline more exit handlers in
 vmx.c
To:     Andrea Arcangeli <aarcange@redhat.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Peter Xu <peterx@redhat.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
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 <20190920212509.2578-15-aarcange@redhat.com>
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 <20190924010056.GB4658@redhat.com>
 <a75d04e1-cfd6-fa2e-6120-1f3956e14153@redhat.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Wed, 25 Sep 2019 09:52:52 +0200
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On 24/09/19 03:55, Andrea Arcangeli wrote:
>> So it's forty bytes.  I think we can leave this out.
> This commit I reverted adds literally 3 inlines called by 3 functions,
> in a very fast path, how many bytes of .text difference did you expect
> by dropping some call/ret from a very fast path when you asked me to
> test it? I mean it's just a couple of insn each.

Actually I was either expecting the difference to be zero, meaning GCC
was already inlining them.

I think it is not inlining the functions because they are still
referenced by vmx_exit_handlers.  After patch 15 you could drop them
from the array, and then GCC should inline them.

Paolo