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Date:   Mon, 31 Jul 2023 18:26:46 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     axboe@kernel.dk, linux-kernel@vger.kernel.org, mingo@redhat.com,
        dvhart@infradead.org, dave@stgolabs.net, andrealmeid@igalia.com,
        Andrew Morton <akpm@linux-foundation.org>, urezki@gmail.com,
        hch@infradead.org, lstoakes@gmail.com,
        Arnd Bergmann <arnd@arndb.de>, linux-api@vger.kernel.org,
        linux-mm@kvack.org, linux-arch@vger.kernel.org,
        malteskarupke@web.de
Subject: Re: [PATCH v1 03/14] futex: Flag conversion
Message-ID: <20230731162646.GO29590@hirez.programming.kicks-ass.net>
References: <20230721102237.268073801@infradead.org>
 <20230721105743.887106899@infradead.org>
 <87bkfsnja3.ffs@tglx>
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On Mon, Jul 31, 2023 at 06:21:56PM +0200, Thomas Gleixner wrote:
> On Fri, Jul 21 2023 at 12:22, Peter Zijlstra wrote:
> > +
> > +static inline bool futex_flags_valid(unsigned int flags)
> > +{
> > +	/* Only 64bit futexes for 64bit code */
> > +	if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) {
> > +		if ((flags & FLAGS_SIZE_MASK) == FLAGS_SIZE_64)
> > +			return false;
> > +	}
> > +
> > +	/* Only 32bit futexes are implemented -- for now */
> > +	if ((flags & FLAGS_SIZE_MASK) != FLAGS_SIZE_32)
> > +		return false;
> > +
> > +	return true;
> > +}
> > +
> > +static inline unsigned int futex_size(unsigned int flags)
> > +{
> > +	unsigned int size = flags & FLAGS_SIZE_MASK;
> > +	return 1 << size; /* {0,1,2,3} -> {1,2,4,8} */
> 
> Lacks a new line and the comment is both misplaced and kinda obvious, no?

Yeah, it was a more complicated transform at some point, I'll fix.