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Date:   Wed, 22 Apr 2020 16:53:56 -0700
From:   Sami Tolvanen <samitolvanen@google.com>
To:     Will Deacon <will@kernel.org>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        James Morse <james.morse@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
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        Masahiro Yamada <masahiroy@kernel.org>,
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Subject: Re: [PATCH v12 03/12] scs: add support for stack usage debugging
Message-ID: <20200422235356.GA128062@google.com>
References: <20191018161033.261971-1-samitolvanen@google.com>
 <20200421021453.198187-1-samitolvanen@google.com>
 <20200421021453.198187-4-samitolvanen@google.com>
 <20200422174602.GB3121@willie-the-truck>
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On Wed, Apr 22, 2020 at 06:46:02PM +0100, Will Deacon wrote:
> > +static void scs_check_usage(struct task_struct *tsk)
> > +{
> > +	static unsigned long highest;
> > +	unsigned long used = __scs_used(tsk);
> > +	unsigned long prev;
> > +	unsigned long curr = highest;
> > +
> > +	while (used > curr) {
> > +		prev = cmpxchg(&highest, curr, used);
> 
> I think this can be cmpxchg_relaxed(), since we don't care about ordering
> here afaict.

Sure, I'll change this in v13. Thanks.

Sami