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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5AD57C43381 for ; Wed, 13 Mar 2019 05:21:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27B5F20693 for ; Wed, 13 Mar 2019 05:21:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552454486; bh=42gIq/hYXNzs43Y3q4Rwx65n3HY42N5F1KeLwLAdrvA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=e4FQXSoYbTRP8+XQXv+mo5OSTEbEVID+Cd627nXmLL0JdptkwGzhQJJOH8ocQ4ojj 9lrHgsJw2TqA7xs4GCHuSi1yPm+mtfA/MOzwEVWF/BlnO76qPvDuh8Pq7IfQpWqJPV QrgMI4FdweqmwITspFkEHQb2ttYZT3bUFPRgeqII= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726937AbfCMFVY (ORCPT ); Wed, 13 Mar 2019 01:21:24 -0400 Received: from wout2-smtp.messagingengine.com ([64.147.123.25]:45735 "EHLO wout2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbfCMFVW (ORCPT ); Wed, 13 Mar 2019 01:21:22 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.west.internal (Postfix) with ESMTP id 9D02838BD; Wed, 13 Mar 2019 01:21:20 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute3.internal (MEProxy); Wed, 13 Mar 2019 01:21:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; bh=aR78W31q72vxmgugCUO4zRYVwt/hNV8R2x/8ymYFgIU=; b=Y59tExhx GKNS4b5q5bZQhE8JfLu/yue+mnCE/qtxShZS6ONFIZCadUJmGwilY3O+AiZOo73g b6XQskb8KQcazK1o0Z9CCq5rHVGJv3fk4KfTwZWAw+cnC2Oxw9bSEGI9cdQKd8Rm BnlrynlD0UX/DNKn7kPHai/+kIufKApqtMtsEUlV/3i9jLyxk5jHjuykM7Z39/v6 Y0TybJ/0+fOy8/+josus7cXyZ0N4e2lV/CTWgnkwDCDLcMnKmE6LorOlGsy7TOWP 4vpxWGoWdYSYKjL18kPzkOXOgj0DA3OrHpOJNR+2y5hl1bx/3vrY9alD0UVeLpOD 079JXKsVGxtmCQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedutddrgeelgdekudcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkofgjfhgggfestdekredtredttdenucfhrhhomhepfdfvohgsihhn ucevrdcujfgrrhguihhnghdfuceothhosghinheskhgvrhhnvghlrdhorhhgqeenucfkph epuddvgedrudeiledrvdefrddukeegnecurfgrrhgrmhepmhgrihhlfhhrohhmpehtohgs ihhnsehkvghrnhgvlhdrohhrghenucevlhhushhtvghrufhiiigvpedv X-ME-Proxy: Received: from eros.localdomain (124-169-23-184.dyn.iinet.net.au [124.169.23.184]) by mail.messagingengine.com (Postfix) with ESMTPA id A7752E427E; Wed, 13 Mar 2019 01:21:16 -0400 (EDT) From: "Tobin C. Harding" To: Andrew Morton Cc: "Tobin C. Harding" , Roman Gushchin , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Matthew Wilcox , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 4/5] slob: Use slab_list instead of lru Date: Wed, 13 Mar 2019 16:20:29 +1100 Message-Id: <20190313052030.13392-5-tobin@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190313052030.13392-1-tobin@kernel.org> References: <20190313052030.13392-1-tobin@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently we use the page->lru list for maintaining lists of slabs. We have a list_head in the page structure (slab_list) that can be used for this purpose. Doing so makes the code cleaner since we are not overloading the lru list. The slab_list is part of a union within the page struct (included here stripped down): union { struct { /* Page cache and anonymous pages */ struct list_head lru; ... }; struct { dma_addr_t dma_addr; }; struct { /* slab, slob and slub */ union { struct list_head slab_list; struct { /* Partial pages */ struct page *next; int pages; /* Nr of pages left */ int pobjects; /* Approximate count */ }; }; ... Here we see that slab_list and lru are the same bits. We can verify that this change is safe to do by examining the object file produced from slob.c before and after this patch is applied. Steps taken to verify: 1. checkout current tip of Linus' tree commit a667cb7a94d4 ("Merge branch 'akpm' (patches from Andrew)") 2. configure and build (select SLOB allocator) CONFIG_SLOB=y CONFIG_SLAB_MERGE_DEFAULT=y 3. dissasemble object file `objdump -dr mm/slub.o > before.s 4. apply patch 5. build 6. dissasemble object file `objdump -dr mm/slub.o > after.s 7. diff before.s after.s Use slab_list list_head instead of the lru list_head for maintaining lists of slabs. Reviewed-by: Roman Gushchin Signed-off-by: Tobin C. Harding --- mm/slob.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/mm/slob.c b/mm/slob.c index 307c2c9feb44..ee68ff2a2833 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -112,13 +112,13 @@ static inline int slob_page_free(struct page *sp) static void set_slob_page_free(struct page *sp, struct list_head *list) { - list_add(&sp->lru, list); + list_add(&sp->slab_list, list); __SetPageSlobFree(sp); } static inline void clear_slob_page_free(struct page *sp) { - list_del(&sp->lru); + list_del(&sp->slab_list); __ClearPageSlobFree(sp); } @@ -283,7 +283,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) spin_lock_irqsave(&slob_lock, flags); /* Iterate through each partially free page, try to find room */ - list_for_each_entry(sp, slob_list, lru) { + list_for_each_entry(sp, slob_list, slab_list) { #ifdef CONFIG_NUMA /* * If there's a node specification, search for a partial @@ -297,7 +297,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) continue; /* Attempt to alloc */ - prev = sp->lru.prev; + prev = sp->slab_list.prev; b = slob_page_alloc(sp, size, align); if (!b) continue; @@ -323,7 +323,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) spin_lock_irqsave(&slob_lock, flags); sp->units = SLOB_UNITS(PAGE_SIZE); sp->freelist = b; - INIT_LIST_HEAD(&sp->lru); + INIT_LIST_HEAD(&sp->slab_list); set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); set_slob_page_free(sp, slob_list); b = slob_page_alloc(sp, size, align); -- 2.21.0