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Date:   Tue, 5 Jul 2022 19:08:53 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Nicholas Piggin <npiggin@gmail.com>
Cc:     Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Waiman Long <longman@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 05/13] locking/qspinlock: be less clever with the
 preprocessor
Message-ID: <YsRwJdjJqpXEFTnO@worktop.programming.kicks-ass.net>
References: <20220704143820.3071004-1-npiggin@gmail.com>
 <20220704143820.3071004-6-npiggin@gmail.com>
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On Tue, Jul 05, 2022 at 12:38:12AM +1000, Nicholas Piggin wrote:
> Stop qspinlock.c including itself and avoid most of the function
> renaming with the preprocessor.
> 
> This is mostly done by having the common slowpath code take a 'bool
> paravirt' argument and adjusting code based on that.

What does code-gen do? Is it clever enough to constant fold the lot?

Should we be using __always_inline to ensure the compiler doesn't decide
against inlining because $raisin and then emitting extra condtionals?