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 89C5AC00140 for ; Mon, 1 Aug 2022 02:06:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237625AbiHACG5 (ORCPT ); Sun, 31 Jul 2022 22:06:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233109AbiHACGx (ORCPT ); Sun, 31 Jul 2022 22:06:53 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 143E3DF77 for ; Sun, 31 Jul 2022 19:06:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659319612; x=1690855612; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=z3o9XhM+vgD3t9N8cNdE+UfIUMTL5F3Mmc63kX4QpwU=; b=HrR21sum+nTzOxu7oU+qDTUP8AAAXHAkxsaBdg/icuBytZYRVyW3ATI/ VnVQI8sj0JmXF1ilqbzCKlEBcluMS1WaMX1UP/1ULFM4DMq1WIlwf+bsa aiGDx74ISncqWuk+iZtjimJoFoQ76iLE7rPXcLF0ODuvIy4Knmnek4Tn4 z2XImQwFachuivu58Ejlk8d9h3a0NAcXRzcSWCM7ocfVLmsGKPU0xo/I6 RGZdCu0wqQQZte8NKhnVT9UvAEywnr0lh0zwCyBFs7hjOrQNq9YAgCaQg gHy8+nva/jSKD9Y/iatlkje+WeKpF5lLrWsw6ZDJlVYn5G2nD/7/o/mqq w==; X-IronPort-AV: E=McAfee;i="6400,9594,10425"; a="290254398" X-IronPort-AV: E=Sophos;i="5.93,206,1654585200"; d="scan'208";a="290254398" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2022 19:06:51 -0700 X-IronPort-AV: E=Sophos;i="5.93,206,1654585200"; d="scan'208";a="577612599" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2022 19:06:48 -0700 From: "Huang, Ying" To: "Aneesh Kumar K.V" Cc: linux-mm@kvack.org, akpm@linux-foundation.org, Wei Xu , Yang Shi , Davidlohr Bueso , Tim C Chen , Michal Hocko , Linux Kernel Mailing List , Hesham Almatary , Dave Hansen , Jonathan Cameron , Alistair Popple , Dan Williams , Johannes Weiner , jvgediya.oss@gmail.com Subject: Re: [PATCH v11 4/8] mm/demotion/dax/kmem: Set node's abstract distance to MEMTIER_ADISTANCE_PMEM References: <20220728190436.858458-1-aneesh.kumar@linux.ibm.com> <20220728190436.858458-5-aneesh.kumar@linux.ibm.com> <875yjgmocg.fsf@yhuang6-desk2.ccr.corp.intel.com> <87bkt8s7w9.fsf@linux.ibm.com> Date: Mon, 01 Aug 2022 10:06:44 +0800 In-Reply-To: <87bkt8s7w9.fsf@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Fri, 29 Jul 2022 12:49:34 +0530") Message-ID: <87k07slnt7.fsf@yhuang6-desk2.ccr.corp.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "Aneesh Kumar K.V" writes: > "Huang, Ying" writes: > >> "Aneesh Kumar K.V" writes: >> >>> By default, all nodes are assigned to the default memory tier which >>> is the memory tier designated for nodes with DRAM >>> >>> Set dax kmem device node's tier to slower memory tier by assigning >>> abstract distance to MEMTIER_ADISTANCE_PMEM. PMEM tier >>> appears below the default memory tier in demotion order. >>> >>> Signed-off-by: Aneesh Kumar K.V >>> --- >>> drivers/dax/kmem.c | 9 +++++++++ >>> include/linux/memory-tiers.h | 19 ++++++++++++++++++- >>> mm/memory-tiers.c | 28 ++++++++++++++++------------ >>> 3 files changed, 43 insertions(+), 13 deletions(-) >>> >>> diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c >>> index a37622060fff..6b0d5de9a3e9 100644 >>> --- a/drivers/dax/kmem.c >>> +++ b/drivers/dax/kmem.c >>> @@ -11,6 +11,7 @@ >>> #include >>> #include >>> #include >>> +#include >>> #include "dax-private.h" >>> #include "bus.h" >>> >>> @@ -41,6 +42,12 @@ struct dax_kmem_data { >>> struct resource *res[]; >>> }; >>> >>> +static struct memory_dev_type default_pmem_type = { >> >> Why is this named as default_pmem_type? We will not change the memory >> type of a node usually. >> > > Any other suggestion? pmem_dev_type? Or dax_pmem_type? DAX is used to enumerate the memory device. > >>> + .adistance = MEMTIER_ADISTANCE_PMEM, >>> + .tier_sibiling = LIST_HEAD_INIT(default_pmem_type.tier_sibiling), >>> + .nodes = NODE_MASK_NONE, >>> +}; >>> + >>> static int dev_dax_kmem_probe(struct dev_dax *dev_dax) >>> { >>> struct device *dev = &dev_dax->dev; >>> @@ -62,6 +69,8 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) >>> return -EINVAL; >>> } >>> >>> + init_node_memory_type(numa_node, &default_pmem_type); >>> + >> >> The memory hot-add below may fail. So the error handling needs to be >> added. >> >> And, it appears that the memory type and memory tier of a node may be >> fully initialized here before NUMA hot-adding started. So I suggest to >> set node_memory_types[] here only. And set memory_dev_type->nodes in >> node hot-add callback. I think there is the proper place to complete >> the initialization. >> >> And, in theory dax/kmem.c can be unloaded. So we need to clear >> node_memory_types[] for nodes somewhere. >> > > I guess by module exit we can be sure that all the memory managed > by dax/kmem is hotplugged out. How about something like below? Because we set node_memorty_types[] in dev_dax_kmem_probe(), it's natural to clear it in dev_dax_kmem_remove(). Best Regards, Huang, Ying > diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c > index 6b0d5de9a3e9..eb4e158012a9 100644 > --- a/drivers/dax/kmem.c > +++ b/drivers/dax/kmem.c > @@ -248,6 +248,7 @@ static void __exit dax_kmem_exit(void) > dax_driver_unregister(&device_dax_kmem_driver); > if (!any_hotremove_failed) > kfree_const(kmem_name); > + unregister_memory_type(&default_pmem_type); > } > > MODULE_AUTHOR("Intel Corporation"); > diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h > index fc6b7a14da51..8355baf5b8b4 100644 > --- a/include/linux/memory-tiers.h > +++ b/include/linux/memory-tiers.h > @@ -31,6 +31,7 @@ struct memory_dev_type { > #ifdef CONFIG_NUMA > extern bool numa_demotion_enabled; > void init_node_memory_type(int node, struct memory_dev_type *default_type); > +void unregister_memory_type(struct memory_dev_type *memtype); > #ifdef CONFIG_MIGRATION > int next_demotion_node(int node); > void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets); > @@ -57,6 +58,10 @@ static inline bool node_is_toptier(int node) > #define numa_demotion_enabled false > static inline void init_node_memory_type(int node, struct memory_dev_type *default_type) > { > +} > + > +static inline void unregister_memory_type(struct memory_dev_type *memtype) > +{ > > } > > diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c > index 064e0f932795..4d29ebd4c4f3 100644 > --- a/mm/memory-tiers.c > +++ b/mm/memory-tiers.c > @@ -500,6 +500,28 @@ void init_node_memory_type(int node, struct memory_dev_type *default_type) > mutex_unlock(&memory_tier_lock); > } > > +void unregister_memory_type(struct memory_dev_type *memtype) > +{ > + int node; > + struct memory_tier *memtier = memtype->memtier; > + > + mutex_lock(&memory_tier_lock); > + for(node = 0; node < MAX_NUMNODES; node++) { > + if (node_memory_types[node] == memtype) { > + if (!nodes_empty(memtype->nodes)) > + WARN_ON(1); > + node_memory_types[node] = NULL; > + } > + } > + > + list_del(&memtype->tier_sibiling); > + memtype->memtier = NULL; > + if (list_empty(&memtier->memory_types)) > + destroy_memory_tier(memtier); > + > + mutex_unlock(&memory_tier_lock); > +} > + > void update_node_adistance(int node, struct memory_dev_type *memtype) > { > pg_data_t *pgdat;