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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A037910FC450 for ; Wed, 8 Apr 2026 21:58:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 10DFF6B0005; Wed, 8 Apr 2026 17:58:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0BF166B0088; Wed, 8 Apr 2026 17:58:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EF0336B0089; Wed, 8 Apr 2026 17:58:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id DF7466B0005 for ; Wed, 8 Apr 2026 17:58:43 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 507851B712C for ; Wed, 8 Apr 2026 21:58:43 +0000 (UTC) X-FDA: 84636753726.04.66C54CE Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf11.hostedemail.com (Postfix) with ESMTP id 8A6F040002 for ; Wed, 8 Apr 2026 21:58:41 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="jK/fHVBB"; spf=pass (imf11.hostedemail.com: domain of baohua@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=baohua@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1775685521; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=gLhQk/GcRQzTBdz6Sgw1idF6hAS9xniYesYPBlEvfFA=; b=Rd3sopyKamx1VWMXKqVK8NzaaJ32I8mH995d20WcasM7e70P7/VwDd15Nn+FAF1IJQYv8I q3dPGQV/KGHcA2eJItgIq4qq6BxWqZ3O9rFtoFw4nwam8wXV0Shu6Vstj0L9XmusqPlP7Y gdFyFQ90HsYXG4gEzQie4U+oNdKywJM= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1775685521; a=rsa-sha256; cv=none; b=LkkdgosBCkg6F5H7xnc63iiA/e101fNazXREBIOkhYzPbIM8NT+TOsjRWapy0V3VzQjtXS bxtCz7PWmD8z3kdwZ4yIVvIdkA09aIQdwng4DGOnCnlyjvdCl9BsmRdIZg73sIxXdCD5g6 ZiuhSB2rcEqSexvt5X7qjQ0u/pbnsPQ= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="jK/fHVBB"; spf=pass (imf11.hostedemail.com: domain of baohua@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=baohua@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 0B16E6011F for ; Wed, 8 Apr 2026 21:58:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3007C19421 for ; Wed, 8 Apr 2026 21:58:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775685520; bh=gLhQk/GcRQzTBdz6Sgw1idF6hAS9xniYesYPBlEvfFA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=jK/fHVBBlK8Ch5c2VQhERNpXDMnvynf/9nH2KPuDEBFwZfWST6DQyIjTJL3EvSm5f XPUnFmF6vlE22ttrL3Jxm5IeUhengTQK6+LQNaMQs7boykglCj82Fd6Y9n16TeJm8f FqIGhZGd8h2h+OkzfU/p7JCtkxvEQ0RsnFQ7UGzn4e+ROFoxZLKZ1M/5/2EW188Sc/ 6c3qeqfu+SKjWSpP2MuiMHWLyd6oWHCqJHIvhcKD5eJyCR4mlBSDvTfZuVcMS1wocG 1iFw2S0xyciWKypOtwhhwuy4DQsAYGEdMZWH0b8DxtbdffzjYzm4HNx7dDfWBPtxeW meWXSRtBZgU2g== Received: by mail-qt1-f175.google.com with SMTP id d75a77b69052e-50d58c513dbso2186211cf.2 for ; Wed, 08 Apr 2026 14:58:40 -0700 (PDT) X-Gm-Message-State: AOJu0Ywe6Ys72Emh1S86SYKe4vTWFNfEuce5lagXZDstc+mE6JNC8Z/H yTaE78mBxO0r5/yMVKz5koQ2wK2QfYxYE+jKM/qguf80Q/ziTcs881SKh49+0+kvARNm1NrdS6g 3eOSDm9GP/9B1iEl90kU7lnuj0Gmxkko= X-Received: by 2002:a05:620a:280c:b0:8cd:7271:65f0 with SMTP id af79cd13be357-8d41da56bfcmr3255803085a.44.1775685520089; Wed, 08 Apr 2026 14:58:40 -0700 (PDT) MIME-Version: 1.0 References: <20260408025115.27368-1-baohua@kernel.org> <20260408025115.27368-8-baohua@kernel.org> <90cfbbb4-9f75-4c67-a1c5-34780b2f7108@arm.com> In-Reply-To: <90cfbbb4-9f75-4c67-a1c5-34780b2f7108@arm.com> From: Barry Song Date: Thu, 9 Apr 2026 05:58:28 +0800 X-Gmail-Original-Message-ID: X-Gm-Features: AQROBzCoMjacDMsJOO1TbJJq704JVsHCBUimPGPOnAYdW4abGNDECmY_PU-x9sA Message-ID: Subject: Re: [RFC PATCH 7/8] mm/vmalloc: Coalesce same page_shift mappings in vmap to avoid pgtable zigzag To: Dev Jain Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, urezki@gmail.com, linux-kernel@vger.kernel.org, anshuman.khandual@arm.com, ryan.roberts@arm.com, ajd@linux.ibm.com, rppt@kernel.org, david@kernel.org, Xueyuan.chen21@gmail.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 8A6F040002 X-Stat-Signature: 34q49a8ak15w5zgroengmmmtukdb8pq6 X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1775685521-746862 X-HE-Meta: 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 XAotFs3Y cCAyEyQAKZRCnlkjRyXDh7zDS75TjaNtzjwGm9mMzXQBbaAHb5DYIRGpLXNjqG++1ffZoVLPP5XfSoHkz0rg7TjllHea1mJRaCPZ8bgboZVESBmNw5HYvplMsrZzI9O1aOxHofxg1BsiFvtFQ9k8Kjc2xZR137jhNWRwUZEEHSdoDIkcTDFtrJy3lbmR3sE7Yg7721aUCy6f1s3/xuHYY39scihhiKUceBjE9ed6tU35QNNRw75vRLoaMziQQzQCAMGE1yUW0io/t1tAwB4IlZ6u4WPlZLFwXu449AotA784oCBkLe4oCTpxpsdSalgmxsUC96cH8PxYFiO3kxKT302tIilZm+O4FPqU6i9ES+qUtCTZhb6mV1b/5Z1OCMcA1R0xVS9VxqtEufsnDKw4zJA2EweKfEAW1Ect5UdBTwCVz5Jbkrh7U3RZ5NjaK2DsO7Iwa Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Apr 8, 2026 at 7:36=E2=80=AFPM Dev Jain wrote: > > > > On 08/04/26 8:21 am, Barry Song (Xiaomi) wrote: > > For vmap(), detect pages with the same page_shift and map them in > > batches, avoiding the pgtable zigzag caused by per-page mapping. > > > > Signed-off-by: Barry Song (Xiaomi) > > --- > > In patch 4, you eliminate the pagetable rewalk, and in patch 5, > you re-introduce it, then in this patch you eliminate it again. > So please just squash this into #5. > Sure. I guess I revealed some of the development process in this patchset. The patch was initially written with page table rewalks for simplicity and then iteratively improved. I agree that nobody really cares how it was originally written :-) Best Regards Barry