Received-SPF: pass (google.com: domain of linux-kernel+bounces-200235-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Content-Type: text/plain;
	charset=utf-8
Precedence: bulk
Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3774.500.171.1.1\))
Subject: Re: [PATCH] livepatch: introduce klp_func called interface
From: zhang warden <zhangwarden@gmail.com>
In-Reply-To: <alpine.LSU.2.21.2405311603260.8344@pobox.suse.cz>
Date: Tue, 4 Jun 2024 16:17:01 +0800
Cc: Petr Mladek <pmladek@suse.com>,
 Josh Poimboeuf <jpoimboe@kernel.org>,
 Jiri Kosina <jikos@kernel.org>,
 Joe Lawrence <joe.lawrence@redhat.com>,
 live-patching@vger.kernel.org,
 LKML <linux-kernel@vger.kernel.org>
Content-Transfer-Encoding: quoted-printable
Message-Id: <0C2ABDBE-FBBA-4CD6-A903-B146EBBF4AC8@gmail.com>
References: <20240520005826.17281-1-zhangwarden@gmail.com>
 <alpine.LSU.2.21.2405200845130.11413@pobox.suse.cz>
 <BBD2A553-6D44-4CD5-94DD-D8B2D5536F94@gmail.com>
 <alpine.LSU.2.21.2405210823590.4805@pobox.suse.cz>
 <ZkxVlIPj9VZ9NJC4@pathway.suse.cz>
 <2551BBD9-735E-4D1E-B1AE-F5A3F0C38815@gmail.com>
 <alpine.LSU.2.21.2405310918430.8344@pobox.suse.cz>
 <FF8C167F-1B6C-4E7D-81A0-CB34E082ACA5@gmail.com>
 <alpine.LSU.2.21.2405311603260.8344@pobox.suse.cz>
To: Miroslav Benes <mbenes@suse.cz>


> On May 31, 2024, at 22:06, Miroslav Benes <mbenes@suse.cz> wrote:
>=20
>> And for the unlikely branch, isn=E2=80=99t the complier will compile =
this branch=20
>> into a cold branch that will do no harm to the function performance?
>=20
> The test (cmp insn or something like that) still needs to be there. =
Since=20
> there is only a simple assignment in the branch, the compiler may just=20=

> choose not to have a cold branch in this case. The only difference is =
in=20
> which case you would jump here. You can see for yourself (and prove me=20=

> wrong if it comes to it).
>=20
> Miroslav

Hi Miroslav,

Yes, more tests should be done in this case according to your opinion.

Regards,
Wardenjohn