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 C062EC46CD2 for ; Tue, 23 Jan 2024 02:12:51 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2D0046B0087; Mon, 22 Jan 2024 21:12:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 280718D0001; Mon, 22 Jan 2024 21:12:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 148886B008C; Mon, 22 Jan 2024 21:12:51 -0500 (EST) 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 015E06B0087 for ; Mon, 22 Jan 2024 21:12:50 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id A14EB1A0478 for ; Tue, 23 Jan 2024 02:12:50 +0000 (UTC) X-FDA: 81708952500.20.0DCE8E4 Received: from out-179.mta1.migadu.com (out-179.mta1.migadu.com [95.215.58.179]) by imf09.hostedemail.com (Postfix) with ESMTP id 9614C140023 for ; Tue, 23 Jan 2024 02:12:48 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="BCY2542/"; spf=pass (imf09.hostedemail.com: domain of gang.li@linux.dev designates 95.215.58.179 as permitted sender) smtp.mailfrom=gang.li@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1705975969; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=JiqFJ3djgll3P+M/6YrFMCqE2soJCrfxlM6Qkrb0hJo=; b=Mo8KYZdeHEt6QjIevjsntdh/PTq8DCJIMyoI+NCUi4G6/RwjvltogxUMXTpHaluFvpKADU 3XmIrcfVQnsIcWBSnKa101ygNXLhrkilfFN9iZNN74hw2q0r9wAepGhiUzKRrgMnuY/nRQ ylviOnbgaeqPVdhIE8I0iVGheKOuqVU= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1705975969; a=rsa-sha256; cv=none; b=j4CqAODeQmLZIsDAPWI+ucabbi/qJo3CTFMfR/vTkasVSqre37mbYGRAA9cMhhakevhqiL 7Y8a8jOBDJBCg39CR/4mibqpbS1M58a+GvV7+nTSUs06gAtekCaAgAe9a92jBubx37/DOb ga5ZNLejn1JkPRoCFhzl2+yPxZyRxSU= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="BCY2542/"; spf=pass (imf09.hostedemail.com: domain of gang.li@linux.dev designates 95.215.58.179 as permitted sender) smtp.mailfrom=gang.li@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: <829fb129-f643-4960-a2da-cd38e5ee8f39@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1705975966; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JiqFJ3djgll3P+M/6YrFMCqE2soJCrfxlM6Qkrb0hJo=; b=BCY2542/N2/xlwmhTkgJ/YNu5Darjyl7TDWNmulm13er7a3H3uBw9LbPYgVz4DC4PACdWS pbjyfMHhyUcmDLDA1wp3PeNNIgbWYuh2XdtdxUKRUg/WQmpgEJ/M3ladQMN1PXx8RmVDVz FzYcU23dmCsIQqbnZlo8PLEU3kf9WxY= Date: Tue, 23 Jan 2024 10:12:18 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v4 6/7] hugetlb: parallelize 2M hugetlb allocation and initialization Content-Language: en-US To: Muchun Song Cc: David Hildenbrand , David Rientjes , Mike Kravetz , Andrew Morton , Tim Chen , Linux-MM , Gang Li , LKML , Gang Li References: <20240118123911.88833-1-gang.li@linux.dev> <20240118123911.88833-7-gang.li@linux.dev> <14e38e95-2bc6-4571-b502-4e3954b4bcc4@linux.dev> <849D7EA4-BCF4-4587-8A78-F3B35B63EAE9@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Gang Li In-Reply-To: <849D7EA4-BCF4-4587-8A78-F3B35B63EAE9@linux.dev> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 9614C140023 X-Rspam-User: X-Stat-Signature: ed1y4e7bpr1iegrhr9cubsps4fmr688h X-Rspamd-Server: rspam03 X-HE-Tag: 1705975968-772924 X-HE-Meta: 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 bry3iSmS R4+YMU3JX0QWWVZB/E9aogvTDLQ6h/uwDd2gGAxmOeMhAwg4ZxaZR1nw+/CAiNPouWdTZhacLI5xel+ejaBZTnaCqow== 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: List-Subscribe: List-Unsubscribe: On 2024/1/22 19:30, Muchun Song wrote: >> On Jan 22, 2024, at 18:12, Gang Li wrote: >> >> On 2024/1/22 15:10, Muchun Song wrote:> On 2024/1/18 20:39, Gang Li wrote: >>>> +static void __init hugetlb_alloc_node(unsigned long start, unsigned long end, void *arg) >>>> { >>>> - unsigned long i; >>>> + struct hstate *h = (struct hstate *)arg; >>>> + int i, num = end - start; >>>> + nodemask_t node_alloc_noretry; >>>> + unsigned long flags; >>>> + int next_node = 0; >>> This should be first_online_node which may be not zero. >> >> That's right. Thanks! >> >>>> - for (i = 0; i < h->max_huge_pages; ++i) { >>>> - if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE)) >>>> + /* Bit mask controlling how hard we retry per-node allocations.*/ >>>> + nodes_clear(node_alloc_noretry); >>>> + >>>> + for (i = 0; i < num; ++i) { >>>> + struct folio *folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY], >>>> + &node_alloc_noretry, &next_node); >>>> + if (!folio) >>>> break; >>>> + spin_lock_irqsave(&hugetlb_lock, flags); >>>> I suspect there will more contention on this lock when parallelizing. >> >> In the worst case, there are only 'numa node number' of threads in >> contention. And in my testing, it doesn't degrade performance, but >> rather improves performance due to the reduced granularity. > > So, the performance does not change if you move the lock out of > loop? > If we move the lock out of loop, then multi-threading becomes single-threading, which definitely reduces performance. ``` + spin_lock_irqsave(&hugetlb_lock, flags); for (i = 0; i < num; ++i) { struct folio *folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY], &node_alloc_noretry, &next_node); if (!folio) break; - spin_lock_irqsave(&hugetlb_lock, flags); __prep_account_new_huge_page(h, folio_nid(folio)); enqueue_hugetlb_folio(h, folio); - spin_unlock_irqrestore(&hugetlb_lock, flags); cond_resched(); } + spin_unlock_irqrestore(&hugetlb_lock, flags); } ```