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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20AD6C54EE9 for ; Thu, 8 Sep 2022 22:18:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229789AbiIHWSg (ORCPT ); Thu, 8 Sep 2022 18:18:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229758AbiIHWSf (ORCPT ); Thu, 8 Sep 2022 18:18:35 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFBC5165BF for ; Thu, 8 Sep 2022 15:18:33 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8B8D961E15 for ; Thu, 8 Sep 2022 22:18:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DB04EC433C1; Thu, 8 Sep 2022 22:18:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1662675513; bh=O2ys2VyjCE5vA0H+MnUESCtQE2sKiZPiGGfKwVkcDms=; h=Date:To:From:Subject:From; b=XnzC9TrUlchCugYGKFe7/YQcmsme3iPGgBD/pDmHcVyanDxspqPncF6AaSZYhQEEd bOtyKeF/UYyw9dBUDZLmfxajT1Er4uJ/kq4vF9i9N21ihBv65HkXiyX8eVz3UWeQ0G hv/8/AKT7E8D/QXnWC7Fi5iXB8bKVIyUfQHzHTeM= Date: Thu, 08 Sep 2022 15:18:32 -0700 To: mm-commits@vger.kernel.org, ying.huang@intel.com, rientjes@google.com, rafael@kernel.org, osalvador@suse.de, mike.kravetz@oracle.com, gregkh@linuxfoundation.org, david@redhat.com, aneesh.kumar@linux.ibm.com, songmuchun@bytedance.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-hugetlb-eliminate-memory-less-nodes-handling.patch added to mm-unstable branch Message-Id: <20220908221832.DB04EC433C1@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm: hugetlb: eliminate memoryless nodes handling has been added to the -mm mm-unstable branch. Its filename is mm-hugetlb-eliminate-memory-less-nodes-handling.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb-eliminate-memory-less-nodes-handling.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Muchun Song Subject: mm: hugetlb: eliminate memoryless nodes handling Date: Thu, 8 Sep 2022 15:58:26 +0800 The memory-notify-based approach aims to handle meoryless nodes, however it just adds complexity to the code as pointed out by David in [1]. The handling of memoryless nodes is introduced by commit 4faf8d950ec4 ("hugetlb: handle memory hot-plug events"). In its commit message we cannot find any necessity of handling this case. So we can simply register/unregister sysfs entries in register_node/unregister_node to simlify the code. BTW, the hotplug callback was added because in hugetlb_register_all_nodes() we register sysfs nodes only for N_MEMORY nodes - see commit 9b5e5d0fdc91, which said it was a preparation for handling memoryless nodes via memory hotplug. Since we want to remove memory hotplug, make sure we only register per-node sysfs for online (N_ONLINE) nodes in hugetlb_register_all_nodes(). https://lore.kernel.org/linux-mm/60933ffc-b850-976c-78a0-0ee6e0ea9ef0@redhat.com/ [1] Link: https://lkml.kernel.org/r/20220908075826.37094-1-songmuchun@bytedance.com Signed-off-by: Muchun Song Suggested-by: David Hildenbrand Acked-by: David Hildenbrand Cc: "Aneesh Kumar K.V" Cc: David Rientjes Cc: Greg Kroah-Hartman Cc: "Huang, Ying" Cc: Mike Kravetz Cc: Muchun Song Cc: Oscar Salvador Cc: Rafael J. Wysocki Signed-off-by: Andrew Morton --- drivers/base/node.c | 8 ++- include/linux/hugetlb.h | 14 ++++++ mm/hugetlb.c | 82 +++++++++++++++++--------------------- 3 files changed, 58 insertions(+), 46 deletions(-) --- a/drivers/base/node.c~mm-hugetlb-eliminate-memory-less-nodes-handling +++ a/drivers/base/node.c @@ -20,6 +20,7 @@ #include #include #include +#include static struct bus_type node_subsys = { .name = "node", @@ -608,10 +609,12 @@ static int register_node(struct node *no node->dev.groups = node_dev_groups; error = device_register(&node->dev); - if (error) + if (error) { put_device(&node->dev); - else + } else { + hugetlb_register_node(node); compaction_register_node(node); + } return error; } @@ -625,6 +628,7 @@ static int register_node(struct node *no */ void unregister_node(struct node *node) { + hugetlb_unregister_node(node); compaction_unregister_node(node); node_remove_accesses(node); node_remove_caches(node); --- a/include/linux/hugetlb.h~mm-hugetlb-eliminate-memory-less-nodes-handling +++ a/include/linux/hugetlb.h @@ -16,6 +16,7 @@ struct ctl_table; struct user_struct; struct mmu_gather; +struct node; #ifndef is_hugepd typedef struct { unsigned long pd; } hugepd_t; @@ -935,6 +936,11 @@ static inline void huge_ptep_modify_prot } #endif +#ifdef CONFIG_NUMA +void hugetlb_register_node(struct node *node); +void hugetlb_unregister_node(struct node *node); +#endif + #else /* CONFIG_HUGETLB_PAGE */ struct hstate {}; @@ -1109,6 +1115,14 @@ static inline void set_huge_pte_at(struc pte_t *ptep, pte_t pte) { } + +static inline void hugetlb_register_node(struct node *node) +{ +} + +static inline void hugetlb_unregister_node(struct node *node) +{ +} #endif /* CONFIG_HUGETLB_PAGE */ static inline spinlock_t *huge_pte_lock(struct hstate *h, --- a/mm/hugetlb.c~mm-hugetlb-eliminate-memory-less-nodes-handling +++ a/mm/hugetlb.c @@ -3864,24 +3864,14 @@ static int hugetlb_sysfs_add_hstate(stru return 0; } -static void __init hugetlb_sysfs_init(void) -{ - struct hstate *h; - int err; - - hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); - if (!hugepages_kobj) - return; +#ifdef CONFIG_NUMA +static bool hugetlb_sysfs_initialized __ro_after_init; - for_each_hstate(h) { - err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, - hstate_kobjs, &hstate_attr_group); - if (err) - pr_err("HugeTLB: Unable to add hstate %s", h->name); - } +static inline void hugetlb_mark_sysfs_initialized(void) +{ + hugetlb_sysfs_initialized = true; } -#ifdef CONFIG_NUMA /* * node_hstate/s - associate per node hstate attributes, via their kobjects, @@ -3937,7 +3927,7 @@ static struct hstate *kobj_to_node_hstat * Unregister hstate attributes from a single node device. * No-op if no hstate attributes attached. */ -static void hugetlb_unregister_node(struct node *node) +void hugetlb_unregister_node(struct node *node) { struct hstate *h; struct node_hstate *nhs = &node_hstates[node->dev.id]; @@ -3967,19 +3957,22 @@ static void hugetlb_unregister_node(stru * Register hstate attributes for a single node device. * No-op if attributes already registered. */ -static int hugetlb_register_node(struct node *node) +void hugetlb_register_node(struct node *node) { struct hstate *h; struct node_hstate *nhs = &node_hstates[node->dev.id]; int err; + if (!hugetlb_sysfs_initialized) + return; + if (nhs->hugepages_kobj) - return 0; /* already allocated */ + return; /* already allocated */ nhs->hugepages_kobj = kobject_create_and_add("hugepages", &node->dev.kobj); if (!nhs->hugepages_kobj) - return -ENOMEM; + return; for_each_hstate(h) { err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, @@ -3989,28 +3982,9 @@ static int hugetlb_register_node(struct pr_err("HugeTLB: Unable to add hstate %s for node %d\n", h->name, node->dev.id); hugetlb_unregister_node(node); - return -ENOMEM; + break; } } - return 0; -} - -static int __meminit hugetlb_memory_callback(struct notifier_block *self, - unsigned long action, void *arg) -{ - int ret = 0; - struct memory_notify *mnb = arg; - int nid = mnb->status_change_nid; - - if (nid == NUMA_NO_NODE) - return NOTIFY_DONE; - - if (action == MEM_GOING_ONLINE) - ret = hugetlb_register_node(node_devices[nid]); - else if (action == MEM_CANCEL_ONLINE || action == MEM_OFFLINE) - hugetlb_unregister_node(node_devices[nid]); - - return notifier_from_errno(ret); } /* @@ -4022,11 +3996,8 @@ static void __init hugetlb_register_all_ { int nid; - get_online_mems(); - hotplug_memory_notifier(hugetlb_memory_callback, 0); - for_each_node_state(nid, N_MEMORY) + for_each_online_node(nid) hugetlb_register_node(node_devices[nid]); - put_online_mems(); } #else /* !CONFIG_NUMA */ @@ -4040,8 +4011,32 @@ static struct hstate *kobj_to_node_hstat static void hugetlb_register_all_nodes(void) { } +static inline void hugetlb_mark_sysfs_initialized(void) +{ +} + #endif +static void __init hugetlb_sysfs_init(void) +{ + struct hstate *h; + int err; + + hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); + if (!hugepages_kobj) + return; + + for_each_hstate(h) { + err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, + hstate_kobjs, &hstate_attr_group); + if (err) + pr_err("HugeTLB: Unable to add hstate %s", h->name); + } + + hugetlb_mark_sysfs_initialized(); + hugetlb_register_all_nodes(); +} + #ifdef CONFIG_CMA static void __init hugetlb_cma_check(void); #else @@ -4104,7 +4099,6 @@ static int __init hugetlb_init(void) report_hugepages(); hugetlb_sysfs_init(); - hugetlb_register_all_nodes(); hugetlb_cgroup_file_init(); #ifdef CONFIG_SMP _ Patches currently in -mm which might be from songmuchun@bytedance.com are mm-hugetlb_vmemmap-simplify-reset_struct_pages.patch mm-hugetlb-simplify-per-node-sysfs-creation-and-removal.patch mm-hugetlb-eliminate-memory-less-nodes-handling.patch