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Date:   Mon, 29 Mar 2021 13:29:54 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Guo Ren <guoren@kernel.org>,
        linux-riscv <linux-riscv@lists.infradead.org>,
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        Anup Patel <anup@brainfault.org>,
        Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Subject: Re: [PATCH v4 3/4] locking/qspinlock: Add
 ARCH_USE_QUEUED_SPINLOCKS_XCHG32
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On Mon, Mar 29, 2021 at 01:16:53PM +0200, Peter Zijlstra wrote:
> Anyway, an additional 'funny' is that I suspect you cannot prove fwd
> progress of the entire primitive with any of this on. But who cares
> about details anyway.. :/

What's the architectural guarantee on LL/SC progress for RISC-V ? And
what if you double loop it like cmpxchg() ?