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 <mhng-aac79f77-a392-42cd-a885-247e7625046c@palmer-mbp2014>
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From:   Huacai Chen <chenhuacai@gmail.com>
Date:   Sun, 1 May 2022 13:12:03 +0800
Message-ID: <CAAhV-H7zX+FdVLRuNDd6Nt4YJGumUsWgoJnEe4E3RuR+dXPraw@mail.gmail.com>
Subject: Re: [PATCH V9 16/24] LoongArch: Add misc common routines
To:     Palmer Dabbelt <palmer@dabbelt.com>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Huacai Chen <chenhuacai@loongson.cn>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Airlie <airlied@linux.ie>,
        Jonathan Corbet <corbet@lwn.net>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-arch <linux-arch@vger.kernel.org>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Li Xuefeng <lixuefeng@loongson.cn>,
        Yanteng Si <siyanteng@loongson.cn>,
        Guo Ren <guoren@kernel.org>, WANG Xuerui <kernel@xen0n.name>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>, guoren@linux.alibaba.com
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Hi, Palmer,

On Sat, Apr 30, 2022 at 9:22 PM Palmer Dabbelt <palmer@dabbelt.com> wrote:
>
> On Sat, 30 Apr 2022 03:41:59 PDT (-0700), Arnd Bergmann wrote:
> > On Sat, Apr 30, 2022 at 12:00 PM Huacai Chen <chenhuacai@gmail.com> wrote:
> >>
> >> On Sat, Apr 30, 2022 at 5:50 PM Arnd Bergmann <arnd@arndb.de> wrote:
> >> >
> >> > On Sat, Apr 30, 2022 at 11:05 AM Huacai Chen <chenhuacai@loongson.cn> wrote:
> >> >
> >> > > +unsigned long __xchg_small(volatile void *ptr, unsigned long val, unsigned int size)
> >> > > +{
> >> > > +       u32 old32, mask, temp;
> >> > > +       volatile u32 *ptr32;
> >> > > +       unsigned int shift;
> >> > > +
> >> > > +       /* Check that ptr is naturally aligned */
> >> >
> >> > As discussed, please remove this function and all the references to it.
> >>
> >> It seems that "generic ticket spinlock" hasn't been merged in 5.18?
> >
> > No, but we can merge it together with the loongarch architecture for 5.19.
> >
> > I suggested you coordinate with Guo Ren and Palmer Dabbelt about how
> > to best merge it. The latest version was pasted two weeks ago [1], and
> > it sounds like there are only minor issues to work out and that I can merge
> > v4 into the asm-generic tree before merging the loongarch code in the
> > same place.
> >
> >      Arnd
> >
> > [1] https://lore.kernel.org/lkml/20220414220214.24556-1-palmer@rivosinc.com/
>
> I can just send another version, IIRC it was just that discussion about
> the memory barrier and there's already prototype code so it shouldn't be
> too bad.  I was hoping to do it sooner, sorry.
I've seen your v4 patches, then I will adjust LoongArch code to use
generic ticket spinlocks.

Huacai