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 5F3BACCA489 for ; Tue, 26 Jul 2022 04:04:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237563AbiGZEEJ (ORCPT ); Tue, 26 Jul 2022 00:04:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237556AbiGZEEH (ORCPT ); Tue, 26 Jul 2022 00:04:07 -0400 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C302E2A27E for ; Mon, 25 Jul 2022 21:04:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1658808246; x=1690344246; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=oVa3FHsyt3TXJj0D7uZDaBI94swmdsKGF+L8lychpBU=; b=cqiBVEtrM21gcwPcxhTsz848PuaSWhs94FNGh3Hi0w4WF0jw3MKB6gSl 4KXoKszKfAGxpGfjqmbARYneV1U4eyfUY69Ek/gm6CPTaJ8VTM/9rZuMS 78UTsRelDdEBfdyT+wCmhtv6W2ROgoTJ8Rcd/b5Amp/1hkCUg6q8t4o1F lfLbXOmDh5PcbGAZhGgvwFtROq96QAA0aYCK0o9FNjGpR4aJBPqiG28lM 6bX5bALAdHxn8GoQ5qDq45Gxwnzv4SrD5R2xm5JNT/jE/145WUR/xfoPa an4+ID6JyxRzei6VnohlMHFzr64fxnXiLPutwgWtAsoZYpnPm1Ks37nwu Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10419"; a="268244298" X-IronPort-AV: E=Sophos;i="5.93,193,1654585200"; d="scan'208";a="268244298" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Jul 2022 21:04:06 -0700 X-IronPort-AV: E=Sophos;i="5.93,193,1654585200"; d="scan'208";a="575326791" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.239.13.94]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Jul 2022 21:04:02 -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 v10 3/8] mm/demotion: Add hotplug callbacks to handle new numa node onlined References: <20220720025920.1373558-1-aneesh.kumar@linux.ibm.com> <20220720025920.1373558-4-aneesh.kumar@linux.ibm.com> Date: Tue, 26 Jul 2022 12:03:58 +0800 In-Reply-To: <20220720025920.1373558-4-aneesh.kumar@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Wed, 20 Jul 2022 08:29:15 +0530") Message-ID: <87fsiowmdt.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: > If the new NUMA node onlined doesn't have a performance level assigned, > the kernel adds the NUMA node to default memory tier. > > Signed-off-by: Aneesh Kumar K.V > --- > include/linux/memory-tiers.h | 1 + > mm/memory-tiers.c | 75 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 76 insertions(+) > > diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h > index ef380a39db3a..3d5f14d57ae6 100644 > --- a/include/linux/memory-tiers.h > +++ b/include/linux/memory-tiers.h > @@ -14,6 +14,7 @@ > #define MEMTIER_PERF_LEVEL_DRAM (1 << (MEMTIER_CHUNK_BITS + 2)) > /* leave one tier below this slow pmem */ > #define MEMTIER_PERF_LEVEL_PMEM (1 << MEMTIER_CHUNK_BITS) > +#define MEMTIER_HOTPLUG_PRIO 100 > > extern bool numa_demotion_enabled; > > diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c > index 41a21cc5ae55..cc3a47ec18e4 100644 > --- a/mm/memory-tiers.c > +++ b/mm/memory-tiers.c > @@ -5,6 +5,7 @@ > #include > #include > #include > +#include > #include > > struct memory_tier { > @@ -64,6 +65,78 @@ static struct memory_tier *find_create_memory_tier(unsigned int perf_level) > return new_memtier; > } > > +static struct memory_tier *__node_get_memory_tier(int node) > +{ > + struct memory_tier *memtier; > + > + list_for_each_entry(memtier, &memory_tiers, list) { > + if (node_isset(node, memtier->nodelist)) > + return memtier; > + } > + return NULL; > +} > + > +static void init_node_memory_tier(int node) set_node_memory_tier()? > +{ > + int perf_level; > + struct memory_tier *memtier; > + > + mutex_lock(&memory_tier_lock); > + > + memtier = __node_get_memory_tier(node); > + if (!memtier) { > + perf_level = node_devices[node]->perf_level; > + memtier = find_create_memory_tier(perf_level); > + node_set(node, memtier->nodelist); > + } > + mutex_unlock(&memory_tier_lock); > +} > + > +static void clear_node_memory_tier(int node) > +{ > + struct memory_tier *memtier; > + > + mutex_lock(&memory_tier_lock); > + memtier = __node_get_memory_tier(node); > + if (memtier) > + node_clear(node, memtier->nodelist); When memtier->nodelist becomes empty, we need to free memtier? > + mutex_unlock(&memory_tier_lock); > +} > + > +/* > + * This runs whether reclaim-based migration is enabled or not, > + * which ensures that the user can turn reclaim-based migration > + * at any time without needing to recalculate migration targets. > + */ The comments doesn't apply here. > +static int __meminit migrate_on_reclaim_callback(struct notifier_block *self, > + unsigned long action, void *_arg) Now we are building memory tiers instead of working on demotion. So I think we should rename the function to memtier_hotplug_callback(). > +{ > + struct memory_notify *arg = _arg; > + > + /* > + * Only update the node migration order when a node is > + * changing status, like online->offline. > + */ > + if (arg->status_change_nid < 0) > + return notifier_from_errno(0); > + > + switch (action) { > + case MEM_OFFLINE: > + clear_node_memory_tier(arg->status_change_nid); > + break; > + case MEM_ONLINE: > + init_node_memory_tier(arg->status_change_nid); > + break; > + } > + > + return notifier_from_errno(0); > +} > + > +static void __init migrate_on_reclaim_init(void) > +{ > + hotplug_memory_notifier(migrate_on_reclaim_callback, MEMTIER_HOTPLUG_PRIO); > +} I suggest to call hotplug_memory_notifier() in memory_tier_init() directly. We are not working on demotion here. > + > static int __init memory_tier_init(void) > { > int node; > @@ -96,6 +169,8 @@ static int __init memory_tier_init(void) > node_property->perf_level = default_memtier_perf_level; > } > mutex_unlock(&memory_tier_lock); > + > + migrate_on_reclaim_init(); > return 0; > } > subsys_initcall(memory_tier_init); Best Regards, Huang, Ying