Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Date:   Tue, 8 Feb 2022 22:46:43 -0800
From:   Yury Norov <yury.norov@gmail.com>
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Andrew Morton <akpm@linux-foundation.org>,
        =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= <mirq-linux@rere.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        David Laight <David.Laight@aculab.com>,
        Joe Perches <joe@perches.com>, Dennis Zhou <dennis@kernel.org>,
        Emil Renner Berthing <kernel@esmil.dk>,
        Nicholas Piggin <npiggin@gmail.com>,
        Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>,
        Alexey Klimov <aklimov@redhat.com>,
        linux-kernel@vger.kernel.org, Sunil Goutham <sgoutham@marvell.com>,
        Geetha sowjanya <gakula@marvell.com>,
        Subbaraya Sundeep <sbhatta@marvell.com>,
        hariprasad <hkelam@marvell.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org
Subject: Re: [PATCH 33/54] net: ethernet: replace bitmap_weight with
 bitmap_weight_{eq,gt,ge,lt,le} for mellanox
Message-ID: <YgNjU8iXJ8WIyh/P@yury-laptop>
References: <20220123183925.1052919-1-yury.norov@gmail.com>
 <20220123183925.1052919-34-yury.norov@gmail.com>
 <Ye6gDK2MA+cshctS@smile.fi.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <Ye6gDK2MA+cshctS@smile.fi.intel.com>
Precedence: bulk

On Mon, Jan 24, 2022 at 02:48:12PM +0200, Andy Shevchenko wrote:
> On Sun, Jan 23, 2022 at 10:39:04AM -0800, Yury Norov wrote:
> > Mellanox code uses bitmap_weight() to compare the weight of bitmap with
> > a given number. We can do it more efficiently with bitmap_weight_{eq, ...}
> > because conditional bitmap_weight may stop traversing the bitmap earlier,
> > as soon as condition is met.
> 
> > -	if (port <= 0 || port > m)
> > +	if (port <= 0 || bitmap_weight_lt(actv_ports.ports, dev->caps.num_ports, port))
> >  		return -EINVAL;
> 
> Can we eliminate now the port <= 0 check? Or at least make it port == 0?

The port is a parameter of exported function. I'd rather not take this risk.
Even if it makes sense, it should be a separate patch anyways.