From nobody Wed Feb 11 05:41:25 2026 Received: from out30-124.freemail.mail.aliyun.com (out30-124.freemail.mail.aliyun.com [115.124.30.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 041235D750 for ; Wed, 6 Mar 2024 10:13:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709720023; cv=none; b=MusrVvZHrbsTnpUyZOXZwmnSBXRRF9Zbs7ObEcklZlHCHZvlMlgy8KTG0+KbQsH8yX95NfCTzQrvuaR4l2Hc6SeRJy0jOjs8FEAaMxiJEg2q+czdHm/nzLQnNzhuN1sFa7Sb+PLwrkwvrHrV4Yx4IyqVpw1SUIbvm8Wr8bRWyIE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709720023; c=relaxed/simple; bh=MzCC0AE/rUvpEAo4tb5cVZ7cGsewHKgZszzxyYlWgms=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=foAprtJ0H+fGcIz4XPbPNRAhY935n/+B6B8RZibPe80XKR0g/n0TKrliKrklrxgYo03xj/EGaw6ob3JSkkmDAEWpmI/+qo07/D10xj++eNB4S7TIkVZI8tDMjNmfSwlWp2xIDi/68x8qdKaHFyuyG+tz/pg6QItpn7+L7BrbJEg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=aVH/oJsK; arc=none smtp.client-ip=115.124.30.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="aVH/oJsK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1709720018; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=jQS6ixAjVk0AC8cKYwTBDAm2HkLKEDsUdifzfOmBcs0=; b=aVH/oJsKmuK6AiXGW+Yhae9St6wsrA+7CYmVTQyL6WXrMA45Ym8q7cE4mc3QAGNjSve/8uzcXVWPvHkxX9Lo1UKlrEko+TNsrrsRzfrKXLFO6PYLgwM5NjXyyZfAuimM0UZnYzeqp8abGal/E6v5Vx+OfdCGAPr9JhSCGrzwp24= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R131e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046060;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0W1xC4Y-_1709720017; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W1xC4Y-_1709720017) by smtp.aliyun-inc.com; Wed, 06 Mar 2024 18:13:38 +0800 From: Baolin Wang To: akpm@linux-foundation.org Cc: muchun.song@linux.dev, osalvador@suse.de, david@redhat.com, linmiaohe@huawei.com, naoya.horiguchi@nec.com, mhocko@kernel.org, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] docs: hugetlbpage.rst: add hugetlb migration description Date: Wed, 6 Mar 2024 18:13:28 +0800 Message-Id: <63fb16e7a4ebc5cb69ce655af86e29b2d8e9ba34.1709719720.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add some description of the hugetlb migration strategy. Signed-off-by: Baolin Wang --- Documentation/admin-guide/mm/hugetlbpage.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/admin-guide/mm/hugetlbpage.rst b/Documentation/a= dmin-guide/mm/hugetlbpage.rst index e4d4b4a8dc97..f34a0d798d5b 100644 --- a/Documentation/admin-guide/mm/hugetlbpage.rst +++ b/Documentation/admin-guide/mm/hugetlbpage.rst @@ -376,6 +376,13 @@ Note that the number of overcommit and reserve pages r= emain global quantities, as we don't know until fault time, when the faulting task's mempolicy is applied, from which node the huge page allocation will be attempted. =20 +The hugetlb may be migrated between the per-node hugepages pool in the fol= lowing +scenarios: memory offline, memory failure, longterm pinning, syscalls(mbin= d, +migrate_pages and move_pages), alloc_contig_range() and alloc_contig_pages= (). +Now only memory offline, memory failure and syscalls allow fallbacking to = allocate +a new hugetlb on a different node if the current node is unable to allocat= e during +hugetlb migration, that means these 3 cases can break the per-node hugepag= es pool. + .. _using_huge_pages: =20 Using Huge Pages --=20 2.39.3