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Message-ID: <972e4d0c69dea4e9659eb9459072b2b7b2fd963b.camel@xry111.site>
Subject: Re: [PATCH 1/4] LoongArch: Use trampoline for exception handlers
 and kill la.abs
From:   Xi Ruoyao <xry111@xry111.site>
To:     Huacai Chen <chenhuacai@kernel.org>,
        Jinyang He <hejinyang@loongson.cn>
Cc:     Youling Tang <tangyouling@loongson.cn>,
        Xuerui Wang <kernel@xen0n.name>, loongarch@lists.linux.dev,
        linux-kernel@vger.kernel.org
Date:   Mon, 16 Jan 2023 13:41:17 +0800
In-Reply-To: <CAAhV-H55Kj4gMnORHfQUYJ3KBueLv7j+ktkNP9cE-=32nEShzg@mail.gmail.com>
References: <1673255274-18238-1-git-send-email-tangyouling@loongson.cn>
         <1673255274-18238-2-git-send-email-tangyouling@loongson.cn>
         <6f1a1f3c-4569-c427-76ae-2f7093cb5e9f@loongson.cn>
         <CAAhV-H55Kj4gMnORHfQUYJ3KBueLv7j+ktkNP9cE-=32nEShzg@mail.gmail.com>
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On Mon, 2023-01-16 at 09:30 +0800, Huacai Chen wrote:
> On Sat, Jan 14, 2023 at 2:38 PM Jinyang He <hejinyang@loongson.cn>
> wrote:
> >=20
> > Hi, Ruoyao and Youling,
> >=20
> > I care about the performance when NUMA enabled. We set CSR.EENTRY
> > for each possible cpus where is NUMA-relative. So, I guess the more
> > codes in NUMA-relative memory makes more performance. If we just set
> > handler_trampoline as exception handler, the performance may be
> > influenced.
> So copying both the handlers and handler_trampoline can solve the
> problem? If that is possible, please do that on top of the latest code
> in
> https://github.com/loongson/linux/commits/loongarch-next

Hi folks,

I just wrote the trampoline code as a PoC to show "relocatable kernel
can work" and there must be some better way.  But I'm too sad to write
any serious code in this month, and I don't have access to a LoongArch
NUMA system.  So I think it's better to leave the job for you guys now
:).

Best regards

--=20
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University