From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f71.google.com (mail-pl0-f71.google.com [209.85.160.71]) by kanga.kvack.org (Postfix) with ESMTP id 7F6E06B0006 for ; Mon, 21 May 2018 11:20:43 -0400 (EDT) Received: by mail-pl0-f71.google.com with SMTP id x32-v6so10184253pld.16 for ; Mon, 21 May 2018 08:20:43 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id n3-v6sor556915pga.330.2018.05.21.08.20.42 for (Google Transport Security); Mon, 21 May 2018 08:20:42 -0700 (PDT) From: Huaisheng Ye Subject: [RFC PATCH v2 00/12] get rid of GFP_ZONE_TABLE/BAD Date: Mon, 21 May 2018 23:20:21 +0800 Message-Id: <1526916033-4877-1-git-send-email-yehs2007@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, linux-mm@kvack.org Cc: mhocko@suse.com, willy@infradead.org, vbabka@suse.cz, mgorman@techsingularity.net, kstewart@linuxfoundation.org, alexander.levin@verizon.com, gregkh@linuxfoundation.org, colyli@suse.de, chengnt@lenovo.com, hehy1@lenovo.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, xen-devel@lists.xenproject.org, linux-btrfs@vger.kernel.org, Huaisheng Ye From: Huaisheng Ye Replace GFP_ZONE_TABLE and GFP_ZONE_BAD with encoded zone number. Delete ___GFP_DMA, ___GFP_HIGHMEM and ___GFP_DMA32 from GFP bitmasks, the bottom three bits of GFP mask is reserved for storing encoded zone number. The encoding method is XOR. Get zone number from enum zone_type, then encode the number with ZONE_NORMAL by XOR operation. The goal is to make sure ZONE_NORMAL can be encoded to zero. So, the compatibility can be guaranteed, such as GFP_KERNEL and GFP_ATOMIC can be used as before. Reserve __GFP_MOVABLE in bit 3, so that it can continue to be used as a flag. Same as before, __GFP_MOVABLE respresents movable migrate type for ZONE_DMA, ZONE_DMA32, and ZONE_NORMAL. But when it is enabled with __GFP_HIGHMEM, ZONE_MOVABLE shall be returned instead of ZONE_HIGHMEM. __GFP_ZONE_MOVABLE is created to realize it. With this patch, just enabling __GFP_MOVABLE and __GFP_HIGHMEM is not enough to get ZONE_MOVABLE from gfp_zone. All callers should use GFP_HIGHUSER_MOVABLE or __GFP_ZONE_MOVABLE directly to achieve that. Decode zone number directly from bottom three bits of flags in gfp_zone. The theory of encoding and decoding is, A ^ B ^ B = A Changes since v1, v2: Add __GFP_ZONE_MOVABLE and modify GFP_HIGHUSER_MOVABLE to help callers to get ZONE_MOVABLE. Add __GFP_ZONE_MASK to mask lowest 3 bits of GFP bitmasks. Modify some callers' gfp flag to update usage of address zone modifiers. Modify inline function gfp_zone to get better performance according to Matthew's suggestion. Link: https://marc.info/?l=linux-mm&m=152596791931266&w=2 Huaisheng Ye (12): include/linux/gfp.h: get rid of GFP_ZONE_TABLE/BAD arch/x86/kernel/amd_gart_64: update usage of address zone modifiers arch/x86/kernel/pci-calgary_64: update usage of address zone modifiers drivers/iommu/amd_iommu: update usage of address zone modifiers include/linux/dma-mapping: update usage of address zone modifiers drivers/xen/swiotlb-xen: update usage of address zone modifiers fs/btrfs/extent_io: update usage of address zone modifiers drivers/block/zram/zram_drv: update usage of address zone modifiers mm/vmpressure: update usage of address zone modifiers mm/zsmalloc: update usage of address zone modifiers include/linux/highmem: update usage of movableflags arch/x86/include/asm/page.h: update usage of movableflags arch/x86/include/asm/page.h | 3 +- arch/x86/kernel/amd_gart_64.c | 2 +- arch/x86/kernel/pci-calgary_64.c | 2 +- drivers/block/zram/zram_drv.c | 6 +-- drivers/iommu/amd_iommu.c | 2 +- drivers/xen/swiotlb-xen.c | 2 +- fs/btrfs/extent_io.c | 2 +- include/linux/dma-mapping.h | 2 +- include/linux/gfp.h | 98 +++++----------------------------------- include/linux/highmem.h | 4 +- mm/vmpressure.c | 2 +- mm/zsmalloc.c | 4 +- 12 files changed, 26 insertions(+), 103 deletions(-) -- 1.8.3.1