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From: Jisheng Zhang <jszhang@kernel.org>
To: linux-riscv@lists.infradead.org,
	PalmerDabbelt <palmer@dabbelt.com>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Albert Ou <aou@eecs.berkeley.edu>, Evan Green <evan@rivosinc.com>
Subject: boot time regressed a lot due to misaligned access probe
Date: Wed, 13 Sep 2023 08:14:08 +0800	[thread overview]
Message-ID: <ZQD+0BWNU8wlnC9d@xhacker> (raw)

Hi all,

Probing one cpu for misaligned access cost about 0.06s, so it will cost
about 3.8s on platforms with 64 CPUs, for example, milkv pioneer which
is powered by sg2042.

I'm not sure the reason of probing misaligned access for all CPUs. If
the HW doesn't behave as SMP from misalligned access side, then unless
userspace processes force cpu affinity, they always suffer from this
non-SMP pain.

So, can we only probe the boot cpu?

Thanks

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             reply	other threads:[~2023-09-13  0:26 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-13  0:14 Jisheng Zhang [this message]
2023-09-13 10:46 ` boot time regressed a lot due to misaligned access probe Ben Dooks
2023-09-13 15:11   ` Jisheng Zhang
2023-09-13 19:50     ` Evan Green
2023-09-13 19:53       ` Palmer Dabbelt
2023-09-15  0:55       ` Jisheng Zhang

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