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 C7694C19F2C for ; Mon, 1 Aug 2022 01:04:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238686AbiHABEb (ORCPT ); Sun, 31 Jul 2022 21:04:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231234AbiHABE2 (ORCPT ); Sun, 31 Jul 2022 21:04:28 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C3C61146C for ; Sun, 31 Jul 2022 18:04:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659315868; x=1690851868; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=MBsZNqKqs+B3csBGzjyuQ2OxAFygDzHNCmXM9erWVhI=; b=Qf2ObXLTuGbWJvPTcbs3Ifgiuzc1hvta6SAF0z+tPuwPwDDCjN0PoYEP vz7Wa/A6AY7p5BlAwQuM9TjhqgLmpgVhPwgU8nAX4D1j/IMDqXtk8Oj7L ExPy1+658bDqJXWvWNufrWvKZqE1KFmP7bbm9O3popeS4ThbLief3SJqO 4Fzopt74FckhgrJ3Yk6uhzUYVXTM2vL8ik5uxQfqyAxJjLPWV1eHFQyhX VYgGJ99cdH7dGjz+LFVnFZMnGr4fJElvgh+yH/IWYk5Qi4sO+JN1naHfg pis5dilK4ZstedOVTTLgNXjzt4eA86jSm65OkjgDW5iUtptATQGiFeJwq w==; X-IronPort-AV: E=McAfee;i="6400,9594,10425"; a="289053326" X-IronPort-AV: E=Sophos;i="5.93,206,1654585200"; d="scan'208";a="289053326" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2022 18:04:27 -0700 X-IronPort-AV: E=Sophos;i="5.93,206,1654585200"; d="scan'208";a="552346665" Received: from unknown (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2022 18:04:23 -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 8/8] mm/demotion: Update node_is_toptier to work with memory tiers References: <20220728190436.858458-1-aneesh.kumar@linux.ibm.com> <20220728190436.858458-9-aneesh.kumar@linux.ibm.com> <87sfmkl8x0.fsf@yhuang6-desk2.ccr.corp.intel.com> <9fa09da8-eff7-e39a-96b0-2bc51711f08f@linux.ibm.com> Date: Mon, 01 Aug 2022 09:04:08 +0800 In-Reply-To: (Aneesh Kumar K. V.'s message of "Fri, 29 Jul 2022 12:17:45 +0530") Message-ID: <87o7x4lqpj.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: > On 7/29/22 12:11 PM, Aneesh Kumar K V wrote: >> On 7/29/22 12:09 PM, Huang, Ying wrote: >>> "Aneesh Kumar K.V" writes: >>> >>>> With memory tiers support we can have memory only NUMA nodes >>>> in the top tier from which we want to avoid promotion tracking NUMA >>>> faults. Update node_is_toptier to work with memory tiers. >>>> All NUMA nodes are by default top tier nodes. With lower memory >>>> tiers added we consider all memory tiers above a memory tier having >>>> CPU NUMA nodes as a top memory tier >>>> >>>> Signed-off-by: Aneesh Kumar K.V >>>> --- >>>> include/linux/memory-tiers.h | 11 ++++++++++ >>>> include/linux/node.h | 5 ----- >>>> mm/huge_memory.c | 1 + >>>> mm/memory-tiers.c | 42 ++++++++++++++++++++++++++++++++++++ >>>> mm/migrate.c | 1 + >>>> mm/mprotect.c | 1 + >>>> 6 files changed, 56 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h >>>> index f8dbeda617a7..bc9fb9d39b2c 100644 >>>> --- a/include/linux/memory-tiers.h >>>> +++ b/include/linux/memory-tiers.h >>>> @@ -35,6 +35,7 @@ struct memory_dev_type *init_node_memory_type(int node, struct memory_dev_type * >>>> #ifdef CONFIG_MIGRATION >>>> int next_demotion_node(int node); >>>> void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets); >>>> +bool node_is_toptier(int node); >>>> #else >>>> static inline int next_demotion_node(int node) >>>> { >>>> @@ -45,6 +46,11 @@ static inline void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *target >>>> { >>>> *targets = NODE_MASK_NONE; >>>> } >>>> + >>>> +static inline bool node_is_toptier(int node) >>>> +{ >>>> + return true; >>>> +} >>>> #endif >>>> >>>> #else >>>> @@ -64,5 +70,10 @@ static inline void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *target >>>> { >>>> *targets = NODE_MASK_NONE; >>>> } >>>> + >>>> +static inline bool node_is_toptier(int node) >>>> +{ >>>> + return true; >>>> +} >>>> #endif /* CONFIG_NUMA */ >>>> #endif /* _LINUX_MEMORY_TIERS_H */ >>>> diff --git a/include/linux/node.h b/include/linux/node.h >>>> index 40d641a8bfb0..9ec680dd607f 100644 >>>> --- a/include/linux/node.h >>>> +++ b/include/linux/node.h >>>> @@ -185,9 +185,4 @@ static inline void register_hugetlbfs_with_node(node_registration_func_t reg, >>>> >>>> #define to_node(device) container_of(device, struct node, dev) >>>> >>>> -static inline bool node_is_toptier(int node) >>>> -{ >>>> - return node_state(node, N_CPU); >>>> -} >>>> - >>>> #endif /* _LINUX_NODE_H_ */ >>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c >>>> index 834f288b3769..8405662646e9 100644 >>>> --- a/mm/huge_memory.c >>>> +++ b/mm/huge_memory.c >>>> @@ -35,6 +35,7 @@ >>>> #include >>>> #include >>>> #include >>>> +#include >>>> >>>> #include >>>> #include >>>> diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c >>>> index 84e2be31a853..36d87dc422ab 100644 >>>> --- a/mm/memory-tiers.c >>>> +++ b/mm/memory-tiers.c >>>> @@ -30,6 +30,7 @@ static DEFINE_MUTEX(memory_tier_lock); >>>> static LIST_HEAD(memory_tiers); >>>> struct memory_dev_type *node_memory_types[MAX_NUMNODES]; >>>> #ifdef CONFIG_MIGRATION >>>> +static int top_tier_adistance; >>>> /* >>>> * node_demotion[] examples: >>>> * >>>> @@ -159,6 +160,31 @@ static struct memory_tier *__node_get_memory_tier(int node) >>>> } >>>> >>>> #ifdef CONFIG_MIGRATION >>>> +bool node_is_toptier(int node) >>>> +{ >>>> + bool toptier; >>>> + pg_data_t *pgdat; >>>> + struct memory_tier *memtier; >>>> + >>>> + pgdat = NODE_DATA(node); >>>> + if (!pgdat) >>>> + return false; >>>> + >>>> + rcu_read_lock(); >>>> + memtier = rcu_dereference(pgdat->memtier); >>>> + if (!memtier) { >>>> + toptier = true; >>>> + goto out; >>>> + } >>>> + if (memtier->adistance_start >= top_tier_adistance) >>>> + toptier = true; >>>> + else >>>> + toptier = false; >>>> +out: >>>> + rcu_read_unlock(); >>>> + return toptier; >>>> +} >>>> + >>>> void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets) >>>> { >>>> struct memory_tier *memtier; >>>> @@ -315,6 +341,22 @@ static void establish_demotion_targets(void) >>>> } >>>> } while (1); >>>> } >>>> + /* >>>> + * Promotion is allowed from a memory tier to higher >>>> + * memory tier only if the memory tier doesn't include >>>> + * compute. We want to skip promotion from a memory tier, >>>> + * if any node that is part of the memory tier have CPUs. >>>> + * Once we detect such a memory tier, we consider that tier >>>> + * as top tiper from which promotion on is not allowed. >>>> + */ >>>> + list_for_each_entry(memtier, &memory_tiers, list) { >>>> + tier_nodes = get_memtier_nodemask(memtier); >>>> + nodes_and(tier_nodes, node_states[N_CPU], tier_nodes); >>>> + if (!nodes_empty(tier_nodes)) { >>>> + top_tier_adistance = memtier->adistance_start; >>> >>> IMHO, this should be, >>> >>> top_tier_adistance = memtier->adistance_start + MEMTIER_CHUNK_SIZE; >>> >> >> Good catch. Will update. BTW i did send v12 version of the patchset already to the list. >> >> > > Checking this again, we consider a node top tier if the node's memtier abstract distance > satisfy the below. > > if (memtier->adistance_start <= top_tier_adistance) > toptier = true; I admit that this works correctly. And I think that the following code is even more correct conceptually. If so, why not help the code reader to understand it more easily? if (memtier->adistance_start + MEMTIER_CHUNK_SIZE <= top_tier_adistance) toptier = true; Best Regards, Huang, Ying > With that we should be good with the current code. But I agree with you that top_tier_distance > should cover the full range of the top memory tier. > > -aneesh