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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 7 Mar 2023 13:06:29 -0800
Message-ID: <CAHk-=whCA4-uc5WV_-68Mpmu-TiSv6fxkSjZ19zzcW9jpSxDvA@mail.gmail.com>
Subject: Re: [PATCH] x86/resctrl: avoid compiler optimization in __resctrl_sched_in
To:     Jakub Jelinek <jakub@redhat.com>
Cc:     Segher Boessenkool <segher@kernel.crashing.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Stephane Eranian <eranian@google.com>,
        linux-kernel@vger.kernel.org, tony.luck@intel.com,
        reinette.chatre@intel.com, fenghua.yu@intel.com,
        peternewman@google.com, james.morse@arm.com, babu.moger@amd.com,
        ananth.narayan@amd.com, vschneid@redhat.com,
        Nathan Chancellor <nathan@kernel.org>,
        clang-built-linux <llvm@lists.linux.dev>,
        Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>, linux-toolchains@vger.kernel.org
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On Tue, Mar 7, 2023 at 12:54=E2=80=AFPM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> I think the problem is that the <asm/resctrl.h> code is disgusting and
> horrible in multiple ways:
>
>  (a) it shouldn't define and declare a static function in a header file
>
>  (b) the resctrl_sched_in() inline function is misdesigned to begin with

Ok, so here's a *ttoally* untested and mindless patch to maybe fix
what I dislike about that resctl code.

Does it fix the code generation issue? I have no idea. But this is
what I would suggest is the right answer, without actually knowing the
code any better, and just going on a mindless rampage.

It seems to compile for me, fwiw.

             Linus

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