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Thu, 10 Apr 2025 14:13:08 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id v1s6F/TR92dxdgAAD6G6ig (envelope-from ); Thu, 10 Apr 2025 14:13:08 +0000 Date: Thu, 10 Apr 2025 16:12:57 +0200 From: Oscar Salvador To: David Hildenbrand Cc: Gavin Shan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, adityag@linux.ibm.com, donettom@linux.ibm.com, gregkh@linuxfoundation.org, rafael@kernel.org, dakr@kernel.org, akpm@linux-foundation.org, shan.gavin@gmail.com Subject: Re: [PATCH] drivers/base/memory: Avoid overhead from for_each_present_section_nr() Message-ID: References: <20250410125110.1232329-1-gshan@redhat.com> <9deb3725-8991-43d1-8c3d-56523fabff28@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 165FC1F444 X-Spam-Level: X-Spamd-Result: default: False [-3.01 / 50.00]; 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ASN(0.00)[asn:25478, ipnet:::/0, country:RU]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,suse.de:dkim,localhost.localdomain:mid] X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spam-Score: -3.01 X-Spam-Flag: NO On Thu, Apr 10, 2025 at 03:55:19PM +0200, Oscar Salvador wrote: > All in all, I think we are better, and the code is slightly simpler? One thing to notice is that maybe we could further improve and leap 'nr' by the number of sections_per_block, so in those scenarios where a memory-block spans multiple sections this could be faster? Just a thought, and maybe not worth it. In the end, we have payed more than once the price of trying to be too smart wrt. sections and boot tricks :-). -- Oscar Salvador SUSE Labs