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Date:   Wed, 10 Nov 2021 09:35:41 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Eric Dumazet <eric.dumazet@gmail.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        Eric Dumazet <edumazet@google.com>, jpoimboe@redhat.com,
        jbaron@akamai.com, rostedt@goodmis.org, ardb@kernel.org
Subject: Re: [PATCH 2/2] jump_label: refine placement of static_keys
Message-ID: <YYuEXQ7Ur9f88pCw@hirez.programming.kicks-ass.net>
References: <20211110010906.1923210-1-eric.dumazet@gmail.com>
 <20211110010906.1923210-3-eric.dumazet@gmail.com>
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On Tue, Nov 09, 2021 at 05:09:06PM -0800, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> With CONFIG_JUMP_LABEL=y, "struct static_key" content is only
> used for the control path.
> 
> Marking them __read_mostly is only needed when CONFIG_JUMP_LABEL=n.
> Otherwise we place them out of the way to increase data locality.
> 
> This patch adds __static_key to centralize this new policy.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  arch/x86/kvm/lapic.c       |  4 ++--
>  arch/x86/kvm/x86.c         |  2 +-
>  include/linux/jump_label.h | 25 +++++++++++++++++--------
>  kernel/events/core.c       |  2 +-
>  kernel/sched/fair.c        |  2 +-
>  net/core/dev.c             |  8 ++++----
>  net/netfilter/core.c       |  2 +-
>  net/netfilter/x_tables.c   |  2 +-
>  8 files changed, 28 insertions(+), 19 deletions(-)
> 

Hurmph, it's a bit cumbersome to always have to add this __static_key
attribute to every definition, and in fact you seem to have missed some.

Would something like:

	typedef struct static_key __static_key static_key_t;

work? I forever seem to forget the exact things you can make a typedef
do :/