Message-ID: <d0d7b726-7149-9982-e63e-8549dea8f915@amd.com>
Date:   Wed, 8 Mar 2023 10:02:46 -0600
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Reply-To: babu.moger@amd.com
Subject: Re: [PATCH] x86/resctrl: avoid compiler optimization in
 __resctrl_sched_in
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        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,
        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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From:   "Moger, Babu" <babu.moger@amd.com>
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On 3/7/23 15:06, Linus Torvalds wrote:
> On Tue, Mar 7, 2023 at 12:54 PM 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

Tested both on GCC and CLANG. Test passes and resctrl limits are working
fine. Thanks for the patch.

Tested-by: Babu Moger <babu.moger@amd.com>

-- 
Thanks
Babu Moger