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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2921BC433E4 for ; Wed, 22 Jul 2020 08:49:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA7912077D for ; Wed, 22 Jul 2020 08:49:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="eRc9g9Ie" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730971AbgGVIt0 (ORCPT ); Wed, 22 Jul 2020 04:49:26 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:29349 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726526AbgGVIt0 (ORCPT ); Wed, 22 Jul 2020 04:49:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595407764; 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: in-reply-to:in-reply-to:references:references; bh=ZUHpIDnSN/WmenwqHmZ9mTzcwD02l0uaA4Y7CipC5gk=; b=eRc9g9Iej4RwzWcV5KW0JeqzeMFdcPTU1L7NyuABhtF5qc5M/9uqfzBiMAq8Cm3tc9vuBD IPVfmEKQZQ06OdkoglkxMRsPJ/KspPLWNihVAiLwZsqi0AUPRQkChu4NbtYeYJTEJ6G3+v lX2+pGvN2T3lZS+pojzQHA0ZH1/v17A= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-375--Sve9uS6OuuqmTN1DPSUwQ-1; Wed, 22 Jul 2020 04:49:19 -0400 X-MC-Unique: -Sve9uS6OuuqmTN1DPSUwQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3185A800C64; Wed, 22 Jul 2020 08:49:18 +0000 (UTC) Received: from localhost (ovpn-12-70.pek2.redhat.com [10.72.12.70]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6C1E05C1C3; Wed, 22 Jul 2020 08:49:16 +0000 (UTC) Date: Wed, 22 Jul 2020 16:49:13 +0800 From: Baoquan He To: Mike Kravetz Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org Subject: Re: [PATCH 5/5] mm/hugetl.c: warn out if expected count of huge pages adjustment is not achieved Message-ID: <20200722084913.GO32539@MiWiFi-R3L-srv> References: <20200720062623.13135-1-bhe@redhat.com> <20200720062623.13135-6-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mike, On 07/20/20 at 05:38pm, Mike Kravetz wrote: > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > > index 467894d8332a..1dfb5d9e4e06 100644 > > --- a/mm/hugetlb.c > > +++ b/mm/hugetlb.c > > @@ -2661,7 +2661,7 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, > > static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, > > nodemask_t *nodes_allowed) > > { > > - unsigned long min_count, ret; > > + unsigned long min_count, ret, old_max; > > NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); > > > > /* > > @@ -2723,6 +2723,7 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, > > * pool might be one hugepage larger than it needs to be, but > > * within all the constraints specified by the sysctls. > > */ > > + old_max = persistent_huge_pages(h); > > while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { > > if (!adjust_pool_surplus(h, nodes_allowed, -1)) > > break; > > @@ -2779,6 +2780,16 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, > > } > > out: > > h->max_huge_pages = persistent_huge_pages(h); > > + if (count != h->max_huge_pages) { > > + char buf[32]; > > + > > + string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); > > + pr_warn("HugeTLB: %s %lu of page size %s failed. Only %s %lu hugepages.\n", > > + count > old_max ? "increasing" : "decreasing", > > + abs(count - old_max), buf, > > + count > old_max ? "increased" : "decreased", > > + abs(old_max - h->max_huge_pages)); > > + } > > spin_unlock(&hugetlb_lock); > > I would prefer if we drop the lock before logging the message. That would > involve grabbing the value of h->max_huge_pages before dropping the lock. Do you think the below change is OK to you to move the message logging after lock dropping? If yes, I will repost with updated patches. diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6a9b7556ce5b..b5aa32a13569 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2661,7 +2661,7 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, nodemask_t *nodes_allowed) { - unsigned long min_count, ret, old_max; + unsigned long min_count, ret, old_max, new_max; NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); /* @@ -2780,7 +2780,10 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, } out: h->max_huge_pages = persistent_huge_pages(h); - if (count != h->max_huge_pages) { + new_max = h->max_huge_pages; + spin_unlock(&hugetlb_lock); + + if (count != new_max) { char buf[32]; string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); @@ -2788,9 +2791,8 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, count > old_max ? "increasing" : "decreasing", abs(count - old_max), buf, count > old_max ? "increased" : "decreased", - abs(old_max - h->max_huge_pages)); + abs(old_max - new_max)); } - spin_unlock(&hugetlb_lock); NODEMASK_FREE(node_alloc_noretry);