linux-kernel - Re: [PATCH 33/54] net: ethernet: replace bitmap_weight with bitmap_weight

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Message-ID: <Ye6gDK2MA+cshctS@smile.fi.intel.com>
Date:   Mon, 24 Jan 2022 14:48:12 +0200
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Yury Norov <yury.norov@...il.com>
Cc:     Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org, Sunil Goutham <sgoutham@...vell.com>,
        Geetha sowjanya <gakula@...vell.com>,
        Subbaraya Sundeep <sbhatta@...vell.com>,
        hariprasad <hkelam@...vell.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org
Subject: Re: [PATCH 33/54] net: ethernet: replace bitmap_weight with
 bitmap_weight_{eq,gt,ge,lt,le} for mellanox

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?

-- 
With Best Regards,
Andy Shevchenko