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Subject: Re: [PATCH] livepatch: introduce klp_func called interface
From: zhang warden <zhangwarden@gmail.com>
In-Reply-To: <ZkxVlIPj9VZ9NJC4@pathway.suse.cz>
Date: Fri, 24 May 2024 16:09:10 +0800
Cc: Miroslav Benes <mbenes@suse.cz>,
 Josh Poimboeuf <jpoimboe@kernel.org>,
 Jiri Kosina <jikos@kernel.org>,
 Joe Lawrence <joe.lawrence@redhat.com>,
 live-patching@vger.kernel.org,
 linux-kernel@vger.kernel.org
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References: <20240520005826.17281-1-zhangwarden@gmail.com>
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To: Petr Mladek <pmladek@suse.com>


> On May 21, 2024, at 16:04, Petr Mladek <pmladek@suse.com> wrote:
>=20
> Another motivation to use ftrace for testing is that it does not
> affect the performance in production.
>=20
> We should keep klp_ftrace_handler() as fast as possible so that we
> could livepatch also performance sensitive functions.
>=20

How about using unlikely() for branch testing? If we use unlikely, maybe =
there is no negative effect to klp_ftrace_handler() once this function =
is called.

Regards,
Wardenjohn