From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20B4AC433F5 for ; Sun, 28 Nov 2021 18:10:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 99C856B0075; Sun, 28 Nov 2021 13:10:37 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 925596B0078; Sun, 28 Nov 2021 13:10:37 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 750CB6B007B; Sun, 28 Nov 2021 13:10:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0207.hostedemail.com [216.40.44.207]) by kanga.kvack.org (Postfix) with ESMTP id 60EBF6B0075 for ; Sun, 28 Nov 2021 13:10:37 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 19EA91848A1DF for ; Sun, 28 Nov 2021 18:10:27 +0000 (UTC) X-FDA: 78859128894.13.859C9D9 Received: from rere.qmqm.pl (rere.qmqm.pl [91.227.64.183]) by imf11.hostedemail.com (Postfix) with ESMTP id 90A88F000201 for ; Sun, 28 Nov 2021 18:10:26 +0000 (UTC) Received: from remote.user (localhost [127.0.0.1]) by rere.qmqm.pl (Postfix) with ESMTPSA id 4J2Gjn33d2zW8; Sun, 28 Nov 2021 19:10:21 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=rere.qmqm.pl; s=1; t=1638123024; bh=JZhqOAoOJwkFLsUnNQo8o++CiFK7HEGKhePgc/FSOF4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BSqkw57UlW2pW1NXQ5wZ96M5n0daMnNFg3ZZGk4QpT65f28st6tvSbAjCuaDYp0Y0 CmyX5dp3fxa/1bsCgFSoiXvYl/Ivrvk/XW5Lhr31jLklN0/6fnKbeszxM4AJMOo6b9 hs1WVqqJVnnkAxwtLxudxAhzHN+6r0DPz2i1TcI1//mgPfBMhwBro3m3CGjmkmEKO0 zFXYptfKQJ6Xhp//QSGLBmM8xlFJVmHJ9/rNfVpoRczyIK6/HJ5953QI6d4A5Zxyqw UnYVoDxFeKZcNpL0K/UJMA5pXP8gOMjtVWWYJxoXBIppSPMAs/Uq2+pv87S9vD8wOI LfWcTnK2w+pRg== X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.3 at mail Date: Sun, 28 Nov 2021 19:10:20 +0100 From: =?iso-8859-2?Q?Micha=B3_Miros=B3aw?= To: Yury Norov Cc: linux-kernel@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" , "Paul E. McKenney" , "Rafael J. Wysocki" , Alexander Shishkin , Alexey Klimov , Amitkumar Karwar , Andi Kleen , Andrew Lunn , Andrew Morton , Andy Gross , Andy Lutomirski , Andy Shevchenko , Anup Patel , Ard Biesheuvel , Arnaldo Carvalho de Melo , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christoph Hellwig , Christoph Lameter , Daniel Vetter , Dave Hansen , David Airlie , David Laight , Dennis Zhou , Dinh Nguyen , Geetha sowjanya , Geert Uytterhoeven , Greg Kroah-Hartman , Guo Ren , Hans de Goede , Heiko Carstens , Ian Rogers , Ingo Molnar , Jakub Kicinski , Jason Wessel , Jens Axboe , Jiri Olsa , Jonathan Cameron , Juri Lelli , Kalle Valo , Kees Cook , Krzysztof Kozlowski , Lee Jones , Marc Zyngier , Marcin Wojtas , Mark Gross , Mark Rutland , Matti Vaittinen , Mauro Carvalho Chehab , Mel Gorman , Michael Ellerman , Mike Marciniszyn , Nicholas Piggin , Palmer Dabbelt , Peter Zijlstra , Petr Mladek , Randy Dunlap , Rasmus Villemoes , Roy Pledge , Russell King , Saeed Mahameed , Sagi Grimberg , Sergey Senozhatsky , Solomon Peachy , Stephen Boyd , Stephen Rothwell , Steven Rostedt , Subbaraya Sundeep , Sudeep Holla , Sunil Goutham , Tariq Toukan , Tejun Heo , Thomas Bogendoerfer , Thomas Gleixner , Ulf Hansson , Vincent Guittot , Vineet Gupta , Viresh Kumar , Vivien Didelot , Vlastimil Babka , Will Deacon , bcm-kernel-feedback-list@broadcom.com, kvm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-csky@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-snps-arc@lists.infradead.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 2/9] lib/bitmap: implement bitmap_{empty,full} with bitmap_weight_eq() Message-ID: References: <20211128035704.270739-1-yury.norov@gmail.com> <20211128035704.270739-3-yury.norov@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline In-Reply-To: <20211128035704.270739-3-yury.norov@gmail.com> X-Stat-Signature: t49nehko885o7ob8xxpttqnf4g35w8xk X-Rspamd-Queue-Id: 90A88F000201 X-Rspamd-Server: rspam07 Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=rere.qmqm.pl header.s=1 header.b=BSqkw57U; spf=pass (imf11.hostedemail.com: domain of mirq-linux@rere.qmqm.pl designates 91.227.64.183 as permitted sender) smtp.mailfrom=mirq-linux@rere.qmqm.pl; dmarc=pass (policy=reject) header.from=rere.qmqm.pl X-HE-Tag: 1638123026-953047 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Nov 27, 2021 at 07:56:57PM -0800, Yury Norov wrote: > Now as we have bitmap_weight_eq(), switch bitmap_full() and > bitmap_empty() to using it. >=20 > Signed-off-by: Yury Norov > --- > include/linux/bitmap.h | 26 ++++++++++---------------- > 1 file changed, 10 insertions(+), 16 deletions(-) >=20 > diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h > index 996041f771c8..2d951e4dc814 100644 > --- a/include/linux/bitmap.h > +++ b/include/linux/bitmap.h > @@ -386,22 +386,6 @@ static inline int bitmap_subset(const unsigned lon= g *src1, > return __bitmap_subset(src1, src2, nbits); > } > =20 > -static inline bool bitmap_empty(const unsigned long *src, unsigned nbi= ts) > -{ > - if (small_const_nbits(nbits)) > - return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); > - > - return find_first_bit(src, nbits) =3D=3D nbits; > -} Since this is supposed to be an optimization, I would go all the way and replace this with the trivial implementation instead: bool bitmap_empty(long *bits, size_t nbits) { for (; nbits >=3D BITS_PER_LONG; ++bits, nbits -=3D BITS_PER_LONG) if (*bits) return false; if (nbits && *bits & BITMAP_LAST_WORD_MASK(nbits)) return false; return true; } =20 Best Regards Micha=B3 Miros=B3aw