From nobody Tue Dec 23 14:23:44 2025 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) (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 70F1D53369 for ; Thu, 1 Feb 2024 13:31:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706794293; cv=none; b=JQvFSgLKpTJjcqCJru3T9SOUBP+Si5isW7DyWxhKTKU9I5JDOB0Y+R1n+OuynzW7qUKUcMjT/Jq1agCe5K0GGxZYOscBHyatGacKEQaE1KRCf3lfodVTlCFUvht/ZPqrrjwVUd3ZJHCX3pJ8q0BmSOn8Oeu61mTnNJ/adK/eV/M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706794293; c=relaxed/simple; bh=T6/oMqfm0cTUFZu7aG4cysOe/uV1jAyX0rldyapQGag=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=p/JOYhiYGrZYvZou20wIJAP/KzzqmUOK6l73sUF8G3e20YogeDhkVAKbSIZ3zstGpi4op34oT2arprOEWUjnjC9kDTRiNP0+gJolmg1ETgslXjEQxDfiKxGqOhnuSRy/U6B+KWLWwXTmgb1hpkgGyN5JvO1sVv0dnl/NCueX7GU= 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=f2iaxKHw; arc=none smtp.client-ip=115.124.30.131 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="f2iaxKHw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1706794282; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=YTeBhqdSU74IlpwBPcbqYdhQu9vEwdBX/KgZ9rQ8d00=; b=f2iaxKHwRYfdAnZsvsKvJF84+YvPrP0z41Chw6K2IlkPvjTa1JgXVk90orxqOZbWD3bLUDazHvrpUFatRJ5iCjwcphwIznGP+He9MaaZEsk7kNgSfO632hLR9WSMsT6Eqw/qa8dkVp82cC1OXrl8JgUyMbTERCb6Wpm5x5TkNqA= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046059;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0W.tpA.q_1706794281; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W.tpA.q_1706794281) by smtp.aliyun-inc.com; Thu, 01 Feb 2024 21:31:22 +0800 From: Baolin Wang To: akpm@linux-foundation.org, muchun.song@linux.dev Cc: osalvador@suse.de, david@redhat.com, mhocko@kernel.org, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH] mm: hugetlb: remove __GFP_THISNODE flag when dissolving the old hugetlb Date: Thu, 1 Feb 2024 21:31:13 +0800 Message-Id: <6f26ce22d2fcd523418a085f2c588fe0776d46e7.1706794035.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 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" Since commit 369fa227c219 ("mm: make alloc_contig_range handle free hugetlb pages"), the alloc_contig_range() can handle free hugetlb pages by allocating a new fresh hugepage, and replacing the old one in the free hugepage pool. However, our customers can still see the failure of alloc_contig_range() when seeing a free hugetlb page. The reason is that, there are few memory on the old hugetlb page's node, and it can not allocate a fresh hugetlb page on the old hugetlb page's node in isolate_or_dissolve_huge_page() with setting __GFP_THISNODE flag. This makes sense to some degree. Later, the commit ae37c7ff79f1 (" mm: make alloc_contig_range handle in-use hugetlb pages") handles the in-use hugetlb pages by isolating it and doing migration in __alloc_contig_migrate_range(), but it can allow fallbacking to other numa node when allocating a new hugetlb in alloc_migration_target(). This introduces inconsistency to handling free and in-use hugetlb. Considering the CMA allocation and memory hotplug relying on the alloc_contig_range() are important in some scenarios, as well as keeping the consistent hugetlb handling, we should remove the __GFP_THISNODE flag in isolate_or_dissolve_huge_page() to allow fallbacking to other numa node, which can solve the failure of alloc_contig_range() in our case. Signed-off-by: Baolin Wang --- mm/hugetlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 9d996fe4ecd9..9c832709728e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3029,7 +3029,7 @@ void restore_reserve_on_error(struct hstate *h, struc= t vm_area_struct *vma, static int alloc_and_dissolve_hugetlb_folio(struct hstate *h, struct folio *old_folio, struct list_head *list) { - gfp_t gfp_mask =3D htlb_alloc_mask(h) | __GFP_THISNODE; + gfp_t gfp_mask =3D htlb_alloc_mask(h); int nid =3D folio_nid(old_folio); struct folio *new_folio; int ret =3D 0; @@ -3088,7 +3088,7 @@ static int alloc_and_dissolve_hugetlb_folio(struct hs= tate *h, * Ref count on new_folio is already zero as it was dropped * earlier. It can be directly added to the pool free list. */ - __prep_account_new_huge_page(h, nid); + __prep_account_new_huge_page(h, folio_nid(new_folio)); enqueue_hugetlb_folio(h, new_folio); =20 /* --=20 2.39.3