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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 930CBC2BA1A for ; Tue, 7 Apr 2020 03:06:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 573EB214DB for ; Tue, 7 Apr 2020 03:06:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="JXczy0Ja" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 573EB214DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 06B398E0039; Mon, 6 Apr 2020 23:06:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F376C8E0001; Mon, 6 Apr 2020 23:06:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DFDAB8E0039; Mon, 6 Apr 2020 23:06:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0056.hostedemail.com [216.40.44.56]) by kanga.kvack.org (Postfix) with ESMTP id C17C38E0001 for ; Mon, 6 Apr 2020 23:06:42 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 7FC81181AEF31 for ; Tue, 7 Apr 2020 03:06:42 +0000 (UTC) X-FDA: 76679571444.25.wrist09_74ba5a64ac314 X-HE-Tag: wrist09_74ba5a64ac314 X-Filterd-Recvd-Size: 5683 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf25.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:06:42 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 029D420BED; Tue, 7 Apr 2020 03:06:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586228801; bh=7DTRInISwtaNaS6TlXlKWd7h+CeQu3l1RwpBDyc0azI=; h=Date:From:To:Subject:In-Reply-To:From; b=JXczy0JacGlO82oFIGGJu+43hbnmoZblGjv0MuJE28gk+rhrUZ4ZPRacPp0Pbb/Fr YkCJ+gzd9OV/w6/FL7OPpz/EmQ/oD60RLY3mtT9Z2OhWbIAuqkXbj1uPcRn0yZJk2i foVoK41ycllFrWIBTsndP55gRmsKoGIw6sGLwYk8= Date: Mon, 06 Apr 2020 20:06:40 -0700 From: Andrew Morton To: akpm@linux-foundation.org, anshuman.khandual@arm.com, dan.j.williams@intel.com, david@redhat.com, gregkh@linuxfoundation.org, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, pasha.tatashin@soleen.com, rafael@kernel.org, torvalds@linux-foundation.org Subject: [patch 052/166] drivers/base/memory.c: drop section_count Message-ID: <20200407030640.V1fjjVZd6%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: David Hildenbrand Subject: drivers/base/memory.c: drop section_count Patch series "mm: drop superfluous section checks when onlining/offlining". Let's drop some superfluous section checks on the onlining/offlining path. This patch (of 3): Since commit c5e79ef561b0 ("mm/memory_hotplug.c: don't allow to online/offline memory blocks with holes") we have a generic check in offline_pages() that disallows offlining memory blocks with holes. Memory blocks with missing sections are just another variant of these type of blocks. We can stop checking (and especially storing) present sections. A proper error message is now printed why offlining failed. section_count was initially introduced in commit 07681215975e ("Driver core: Add section count to memory_block struct") in order to detect when it is okay to remove a memory block. It was used in commit 26bbe7ef6d5c ("drivers/base/memory.c: prohibit offlining of memory blocks with missing sections") to disallow offlining memory blocks with missing sections. As we refactored creation/removal of memory devices and have a proper check for holes in place, we can drop the section_count. This also removes a leftover comment regarding the mem_sysfs_mutex, which was removed in commit 848e19ad3c33 ("drivers/base/memory.c: drop the mem_sysfs_mutex"). Link: http://lkml.kernel.org/r/20200127110424.5757-2-david@redhat.com Signed-off-by: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Michal Hocko Cc: Dan Williams Cc: Pavel Tatashin Cc: Anshuman Khandual Signed-off-by: Andrew Morton --- drivers/base/memory.c | 17 +++-------------- include/linux/memory.h | 1 - 2 files changed, 3 insertions(+), 15 deletions(-) --- a/drivers/base/memory.c~drivers-base-memoryc-drop-section_count +++ a/drivers/base/memory.c @@ -267,10 +267,6 @@ static int memory_subsys_offline(struct if (mem->state == MEM_OFFLINE) return 0; - /* Can't offline block with non-present sections */ - if (mem->section_count != sections_per_block) - return -EINVAL; - return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE); } @@ -627,7 +623,7 @@ static int init_memory_block(struct memo static int add_memory_block(unsigned long base_section_nr) { - int ret, section_count = 0; + int section_count = 0; struct memory_block *mem; unsigned long nr; @@ -638,12 +634,8 @@ static int add_memory_block(unsigned lon if (section_count == 0) return 0; - ret = init_memory_block(&mem, base_memory_block_id(base_section_nr), - MEM_ONLINE); - if (ret) - return ret; - mem->section_count = section_count; - return 0; + return init_memory_block(&mem, base_memory_block_id(base_section_nr), + MEM_ONLINE); } static void unregister_memory(struct memory_block *memory) @@ -679,7 +671,6 @@ int create_memory_block_devices(unsigned ret = init_memory_block(&mem, block_id, MEM_OFFLINE); if (ret) break; - mem->section_count = sections_per_block; } if (ret) { end_block_id = block_id; @@ -688,7 +679,6 @@ int create_memory_block_devices(unsigned mem = find_memory_block_by_id(block_id); if (WARN_ON_ONCE(!mem)) continue; - mem->section_count = 0; unregister_memory(mem); } } @@ -717,7 +707,6 @@ void remove_memory_block_devices(unsigne mem = find_memory_block_by_id(block_id); if (WARN_ON_ONCE(!mem)) continue; - mem->section_count = 0; unregister_memory_block_under_nodes(mem); unregister_memory(mem); } --- a/include/linux/memory.h~drivers-base-memoryc-drop-section_count +++ a/include/linux/memory.h @@ -26,7 +26,6 @@ struct memory_block { unsigned long start_section_nr; unsigned long state; /* serialized by the dev->lock */ - int section_count; /* serialized by mem_sysfs_mutex */ int online_type; /* for passing data to online routine */ int phys_device; /* to which fru does this belong? */ struct device dev; _