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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39B3EC19F21 for ; Wed, 27 Jul 2022 01:53:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C95BD6B0071; Tue, 26 Jul 2022 21:53:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BA8B3900002; Tue, 26 Jul 2022 21:53:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9D4566B0073; Tue, 26 Jul 2022 21:53:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 761E26B0071 for ; Tue, 26 Jul 2022 21:53:12 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 51E2580AF3 for ; Wed, 27 Jul 2022 01:53:12 +0000 (UTC) X-FDA: 79731207024.10.DDC3997 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf05.hostedemail.com (Postfix) with ESMTP id AC78810008F for ; Wed, 27 Jul 2022 01:53:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1658886791; x=1690422791; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=d+eyjwKRKtr2OzmTv9uExOvL3SJhLVSG/OVMV6nZByk=; b=GxEeg81H3F4uB9FfAPblCWO+6dcQ7rHTHQiAR6pnOV54OC/yq9+g8Yce Stuce83x4y/6bPBeGvEUW8FXNHcIQmm2WBUTbxHIdkG+uZ2q5vEGJERH1 Q+fXkUQjHoumW9IS+IRP0MBESuEsswEBYhauSiPuJNsW9yb3z31kD/tkk oCHvHDaOeO0FWt3woXBa4RWexpi8/eS7xpRIyBzqVg4/R+no/ew5YUv9v BMkiTkOkuzNHpBL8q4j2uqRz1g1vv6qocTRweTt4stYsMe+XtrvMpn6mu jde7yJ5cuRY0VwZSVrpnIIPghShDGxkr2LBbiFyx7ftOiNRYWr5JlGpRQ w==; X-IronPort-AV: E=McAfee;i="6400,9594,10420"; a="267888579" X-IronPort-AV: E=Sophos;i="5.93,194,1654585200"; d="scan'208";a="267888579" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2022 18:53:10 -0700 X-IronPort-AV: E=Sophos;i="5.93,194,1654585200"; d="scan'208";a="927598707" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.239.13.94]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2022 18:53:06 -0700 From: "Huang, Ying" To: Aneesh Kumar K V , Alistair Popple 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 , 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> <87fsiowmdt.fsf@yhuang6-desk2.ccr.corp.intel.com> <28582201-b438-9ac9-ca6b-1ee6e5794dd2@linux.ibm.com> Date: Wed, 27 Jul 2022 09:53:03 +0800 In-Reply-To: <28582201-b438-9ac9-ca6b-1ee6e5794dd2@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Tue, 26 Jul 2022 17:33:37 +0530") Message-ID: <87czdruxs0.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 ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=GxEeg81H; spf=pass (imf05.hostedemail.com: domain of ying.huang@intel.com designates 192.55.52.136 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1658886792; a=rsa-sha256; cv=none; b=cu8dVQfxjpq9zjAPun4XgZK4FBVer58wyIJrMN+WX2t15H/CnbAEbSOvg1VPbcVAXFq6of vh79ScJg+geLp4QTMczceqrjJG08HwMhn5lg9N1khiwD4XCuRXG293Oxg4DCRWtRfgL1Bn ZwRtzQYH53MSddD8Q7qj4ubIKmo/2T8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658886792; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=cd1hzycAOIDJ3+nVwYqum9sv6eKDXYRKzEGX2x9bVQU=; b=PDDvrayDSV9uB/n6Dum69863nWt4Dr7BDPGd2IMahmR36Hx95TAg7enhboRnA57CmFaNbM O6LqjuCEsWJgPiG4jpyz5s0ZIIdR2yUyvKREuWGcFTWVk/5IuxxFvt6f84DvOoY0hihQm3 wR14duUEBsqKg3ZnB8nRGlc3ho1o2Wc= X-Stat-Signature: k9ftka38wwqhgu1cj5y93s9hhzewpjzi X-Rspamd-Queue-Id: AC78810008F X-Rspam-User: Authentication-Results: imf05.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=GxEeg81H; spf=pass (imf05.hostedemail.com: domain of ying.huang@intel.com designates 192.55.52.136 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspamd-Server: rspam02 X-HE-Tag: 1658886791-472268 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: Aneesh Kumar K V writes: > On 7/26/22 9:33 AM, Huang, Ying wrote: >> "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()? > > That was done based on feedback from Alistair > > https://lore.kernel.org/linux-mm/87h73iapg1.fsf@nvdebian.thelocal > >> >>> +{ >>> + 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); >>> + } It's related to Alistair's comments too. When will memtier != NULL here? We may need just VM_WARN_ON() here? >>> + 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 > > > Will update the patch in next iteration to take care of other feedback. Thanks! Best Regards, Huang, Ying