From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f44.google.com (mail-lf1-f44.google.com [209.85.167.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 82F062DAFCC for ; Wed, 20 May 2026 07:32:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779262348; cv=none; b=qQJXoOUbO3awEnyFZmKim2pofmrFnkZ7DbVf4LGJ77S/68lLOyOhBOLz+WhJbi+o+1fuZF2D+bpVVKblYR1HtifV6CNWVZYW94qe04IekYH68A5WapbuD7YVIOSRv4Dq2uvVXgRgwVaIDjENUGsgWjbO06RrVr68Wv1Hb3ZuKkc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779262348; c=relaxed/simple; bh=t8QVfFquUndm4EJddwB8yWSqtecdNWqOCsprpbJULRA=; h=From:Date:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EbafkD3T76b7kFpcVupIEi9KocQxjmhpB8HbSi3VWap3kPluZ8RAjtaPgOC20VCzPbS0I7MOMfzH8T96d8kOm59f40smcbkiyy1tucuivHuEKc903tH88Yj0eqLuXXspPB0dI4cVH7xMWRGfKvegfc8rwc8u3IQB7cUGVdpmj5E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=etfCBSRs; arc=none smtp.client-ip=209.85.167.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="etfCBSRs" Received: by mail-lf1-f44.google.com with SMTP id 2adb3069b0e04-5a88de2b52eso6295689e87.2 for ; Wed, 20 May 2026 00:32:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779262345; x=1779867145; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=+FrgwpGM2Ey9DAqvdXlbg9+ub1m+pVkWeD4ut37zc88=; b=etfCBSRsD44HLhHd/gombVrQESMXhE7GDIMmxV7igO+ioSYJYQbUsvo8gQ2t+wBkTc rLqC8ldDVJHmqSA6mzajkvMwInE59QGYfOe51GrRbWujmBwTvVIQMm3rTMW4cAIv9v3f ztxtsVceGMj60hvd0GBR1qanNfAVvtUXJBlFCSR8xdSj7Zr84LpYYPuCr/IfGUz0yDro o8YRQQhR3mr0pBCoKCS6nW1qMe47JEuL7kgxmjhizG4yFv/7ofHm8yNrhY2yLMEPGUUZ xJNFnlArovCIUtneUoanz6eOeAFhRUD0dgcb8oIx/PeCU7q0+rHvFclGb5MH8V0+uKY+ +Spw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779262345; x=1779867145; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+FrgwpGM2Ey9DAqvdXlbg9+ub1m+pVkWeD4ut37zc88=; b=NgC8znu802EAWL+nnmJ5lI4P/HpiCIC5tz/cKUeaPmuvHPWAKlBTQAZT1tDaBMC+RK /LO5F8/j23HqyARihnRdfxV6BGfcfp54iDfwCmu5iU2spqOIHIzi0xf7mePns+2nzPV+ hvyej+u8VHxxVjE51WbtpCCmFzaaxvjZ/DTGbsiG+jrB5Y2FVc24LrqZw4JuDIATisjD z5ptQnWwziVJOZlq6kel077cuidviqfV6ZDqRw/0m4KeP6pV5Hc2LRVUNSOFm24ogg6M 8bg/aP5CSRFbRHljzrVD3DY5mlVn2hb03+H/gWPO4jj6WnQimMjuuliMZlv53Ilpal30 u0hQ== X-Forwarded-Encrypted: i=1; AFNElJ/xSUpN3oEdSijshAevgBPCxwH2jY/IYeVDzTy5PLjIGFPMcBX9QLfpwtxwJID16GYOcTPlQYorfGiJDqE=@vger.kernel.org X-Gm-Message-State: AOJu0YyBYfGSEYT7IbnnHokYe/kdxlOtPXRadFvihskhlis+ezAtbjcf HC3kFArGPnfDkwotDLErl+VIQAfGVTolOA5mrt3nKZEJfQvFMNPtxyRB X-Gm-Gg: Acq92OE4vzTJS0cJV10FKrgntVZo80CxXQZQaxeKtvtFQ+WfOjj4oUmxxA8xA7X4gJH Xhw1eHvwuCmPfSo9vFDEl71XfjCNVa0A6FD39jUmiJJBbRdq6TfIH6kcJJJr7HB0m5FFtHH3VYl HYIXgf8Rz5iYZVjxigu0Owu/QeudxGR/si6+TWvcbStnW46L/uhVZirffHQ3C3Gm50+uzAMRO2W +LAaMkXkROiyqwLA6pAJYiq4xFiY4DMS9Ov1ye+tijMMyzxjwcR9asDYmAN50RF70VbvDOIJ93X bIXXogQ+eJz+64/N8C4aJwde+Mbob4R0cFsHV/sXh1Q34tzlC0D3plUiE6U/mz4F75y+O2ogRWP 6Zrno3lPIxRPhKP0hgpjvU79ukdgEcrzVnpksYMyUt4gQARVfTSKrwZr2AK4RFkBF X-Received: by 2002:a05:6512:1291:b0:5a3:fcb2:c6a1 with SMTP id 2adb3069b0e04-5aa0e614047mr7302936e87.13.1779262344292; Wed, 20 May 2026 00:32:24 -0700 (PDT) Received: from milan ([2001:9b1:d5a0:a500::24b]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-5a9164bc462sm4733129e87.45.2026.05.20.00.32.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 May 2026 00:32:23 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Wed, 20 May 2026 09:32:22 +0200 To: Wen Jiang 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, baohua@kernel.org, Xueyuan.chen21@gmail.com, dev.jain@arm.com, rppt@kernel.org, david@kernel.org, ryan.roberts@arm.com, anshuman.khandual@arm.com, ajd@linux.ibm.com, linux-kernel@vger.kernel.org, Wen Jiang Subject: Re: [PATCH v2 6/7] mm/vmalloc: align vm_area so vmap() can batch mappings Message-ID: References: <20260514094108.2016201-1-jiangwen6@xiaomi.com> <20260514094108.2016201-7-jiangwen6@xiaomi.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: <20260514094108.2016201-7-jiangwen6@xiaomi.com> On Thu, May 14, 2026 at 05:41:07PM +0800, Wen Jiang wrote: > From: "Barry Song (Xiaomi)" > > Try to align the vmap virtual address to PMD_SHIFT or a > larger PTE mapping size hinted by the architecture, so > contiguous pages can be batch-mapped when setting PMD or > PTE entries. > > Signed-off-by: Barry Song (Xiaomi) > Signed-off-by: Wen Jiang > Tested-by: Xueyuan Chen > --- > mm/vmalloc.c | 31 ++++++++++++++++++++++++++++++- > 1 file changed, 30 insertions(+), 1 deletion(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index c30a7673e..b3389c8f1 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3591,6 +3591,35 @@ static int __vmap_huge(unsigned long addr, unsigned long end, > return err; > } > > +static struct vm_struct *get_aligned_vm_area(unsigned long size, unsigned long flags) > +{ > + unsigned int shift = (size >= PMD_SIZE) ? PMD_SHIFT : > + arch_vmap_pte_supported_shift(size); > + struct vm_struct *vm_area = NULL; > + > + /* > + * Try to allocate an aligned vm_area so contiguous pages can be > + * mapped in batches. > + */ > + while (1) { > + unsigned long align = 1UL << shift; > + > + vm_area = __get_vm_area_node(size, align, PAGE_SHIFT, flags, > + VMALLOC_START, VMALLOC_END, > + NUMA_NO_NODE, GFP_KERNEL, > + __builtin_return_address(0)); > + if (vm_area || shift <= PAGE_SHIFT) > + goto out; > + if (shift == PMD_SHIFT) > + shift = arch_vmap_pte_supported_shift(size); > + else if (shift > PAGE_SHIFT) > + shift = PAGE_SHIFT; > + } > + > +out: > + return vm_area; > +} > + IMO, we should get rid of this while(1) loop. It looks like you need to handle just few cases. 3? shift min value is PAGE_SHIFT, could you please clarify when it can be less? -- Uladzislau Rezki