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Date:   Sun, 13 Mar 2022 00:10:48 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Frederic Weisbecker <frederic@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>, Phil Auld <pauld@redhat.com>,
        Alex Belits <abelits@marvell.com>,
        Nicolas Saenz Julienne <nsaenz@kernel.org>,
        Xiongfeng Wang <wangxiongfeng2@huawei.com>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Yu Liao <liaoyu15@huawei.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        "Paul E . McKenney" <paulmck@kernel.org>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Uladzislau Rezki <uladzislau.rezki@sony.com>,
        Joel Fernandes <joel@joelfernandes.org>
Subject: Re: [PATCH 14/19] rcu/context-tracking: Move RCU-dynticks internal
 functions to context_tracking
Message-ID: <20220312231048.GI28057@worktop.programming.kicks-ass.net>
References: <20220302154810.42308-1-frederic@kernel.org>
 <20220302154810.42308-15-frederic@kernel.org>
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On Wed, Mar 02, 2022 at 04:48:05PM +0100, Frederic Weisbecker wrote:
> +noinstr unsigned long rcu_dynticks_inc(int incby)
> +{
> +	return arch_atomic_add_return(incby, this_cpu_ptr(&context_tracking.dynticks));
> +}

noinstr implies noinline, making the above a rather sad little function;
would it perhaps be better to make it __always_inline ?

Also; I could imagine myself doing an arch special for this such that
x86 generates:

	LOCK XADD	[reg], %gs:[var]

But that's for later I suppose, it would be but a little tweak to
perpcu_add_return_op()