Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 24 Jan 2022 14:28:00 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Yury Norov <yury.norov@gmail.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, Ariel Elior <aelior@marvell.com>,
        Manish Chopra <manishc@marvell.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org
Subject: Re: [PATCH 10/54] net: ethernet: replace bitmap_weight with
 bitmap_empty for qlogic
Message-ID: <Ye6bUC1GyLLUV37p@smile.fi.intel.com>
References: <20220123183925.1052919-1-yury.norov@gmail.com>
 <20220123183925.1052919-11-yury.norov@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20220123183925.1052919-11-yury.norov@gmail.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Precedence: bulk

On Sun, Jan 23, 2022 at 10:38:41AM -0800, Yury Norov wrote:
> qlogic/qed code calls bitmap_weight() to check if any bit of a given
> bitmap is set. It's better to use bitmap_empty() in that case because
> bitmap_empty() stops traversing the bitmap as soon as it finds first
> set bit, while bitmap_weight() counts all bits unconditionally.

> -		if (bitmap_weight((unsigned long *)&pmap[item], 64 * 8))
> +		if (!bitmap_empty((unsigned long *)&pmap[item], 64 * 8))

> -	    (bitmap_weight((unsigned long *)&pmap[item],
> +	    (!bitmap_empty((unsigned long *)&pmap[item],

Side note, these castings reminds me previous discussion and I'm wondering
if you have this kind of potentially problematic places in your TODO as
subject to fix.


-- 
With Best Regards,
Andy Shevchenko