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Date:   Mon, 15 Mar 2021 19:34:15 +0100
From:   Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
To:     Vipin Sharma <vipinsh@google.com>
Cc:     tj@kernel.org, rdunlap@infradead.org, thomas.lendacky@amd.com,
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Subject: Re: [Patch v3 1/2] cgroup: sev: Add misc cgroup controller
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References: <20210304231946.2766648-1-vipinsh@google.com>
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On Fri, Mar 12, 2021 at 11:07:14AM -0800, Vipin Sharma <vipinsh@google.com>=
 wrote:
> We should be fine without atomic64_t because we are using unsigned
> long and not 64 bit explicitly. This will work on both 32 and 64 bit
> machines.
I see.

> But I will add READ_ONCE and WRITE_ONCE because of potential chances of
> load tearing and store tearing.
>=20
> Do you agree?
Yes.

> This was only here to avoid multiple reads of capacity and making sure
> if condition and seq_print will see the same value.
Aha.

> Also, I was not aware of load and store tearing of properly aligned
> and machine word size variables. I will add READ_ONCE and WRITE_ONCE
> at other places.
Yeah, although it's theoretical, I think it also serves well to annotate
such unsychronized accesses.

Thanks,
Michal

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