From nobody Fri Oct 2 08:25:53 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6252B3FFF94 for ; Mon, 3 Aug 2026 13:38:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785764285; cv=none; b=A/88FJyDJr6UA28tl81DR9jRMOGyDSSQunsWb9g4koml0cbnCPUwBDleE2jepcGcHbA6+ANgYdAaxRo7ZZ0AChCtAnYwL1+b6VUzov9aUdUPanzR8ORn4sv2YynMRci1HAml5SOT7ZBw7kZPjMhazG21Sj+kXIyhvvmwDK+DVBQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785764285; c=relaxed/simple; bh=40q8fHgrl8IDhLHqWUcb4B48rq7YY/FRZG1EdbUo6Zc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=p5b5eKZC5qqOATFja2qyoZJ8K7fHrgSo5JRBFdLmTye2a7rjQtDItx/QB/Ux1EdNBoeNMbP8iqrTfna3softvrpKtUSgZgcww9ZvdVsglpJuCgioTt9TgBt6gzhdUoffdrMnwCyLTPWSucI4llwucp071TDG00BhafJ8C34GjzU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QPbS+zgo; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QPbS+zgo" Received: by smtp.kernel.org (Postfix) with ESMTPS id 08419C2BCF4; Mon, 3 Aug 2026 13:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1785764285; bh=40q8fHgrl8IDhLHqWUcb4B48rq7YY/FRZG1EdbUo6Zc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=QPbS+zgodnxPQGiJyFIgllRtmV8vNj/3Tv0CUylyalZ7OTfpaFQalUVs7/mNJVPBt ZDYvZly8ujRRcUUep0N0JqorzhPF8vvyszaL0DP7sb6o1aryPLyKDGuk3fn8prDjZP tS50PHX7A65A9xmKtD19ZUHHlczQHbumFWx8gap+KuGyrxhe6pHyv0j0UMEAY9W1xr gxNKVKwKS4f+JKuS4mj22rRbyXKBgjQGG8MnXyvMd+diOhPSQnyxtzLthj4o6igH9R wlMEp4lkItzyEBxAkUYjqD7JR+ScQSl5SbK3MY8UmXsNrGQw/N6i5XhY+aOccfwo48 AYPk3pfBOvQwQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA435C55179; Mon, 3 Aug 2026 13:38:04 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Mon, 03 Aug 2026 06:37:58 -0700 Subject: [PATCH v5 1/3] mm: hugetlb: Consolidate interpretation of gbl_chg within alloc_hugetlb_folio() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260803-hugetlb-mpol-interpretation-v5-1-af2b7089f8a9@google.com> References: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> In-Reply-To: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> To: Alistair Popple , Andrew Morton , Byungchul Park , David Hildenbrand , Gregory Price , Joshua Hahn , Matthew Brost , Muchun Song , Oscar Salvador , Rakie Kim , Ying Huang , Zi Yan , erdemaktas@google.com, fvdl@google.com, jiaqiyan@google.com, jthoughton@google.com, mhocko@kernel.org, michael.roth@amd.com, pasha.tatashin@soleen.com, pbonzini@redhat.com, peterx@redhat.com, pratyush@kernel.org, rick.p.edgecombe@intel.com, rientjes@google.com, roman.gushchin@linux.dev, seanjc@google.com, shakeel.butt@linux.dev, shivankg@amd.com, vannapurve@google.com, yan.y.zhao@intel.com, Jason Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1785764284; l=2991; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=rwfMlDQJWltPz5tqq1rs54f6f20kc49IZ7Zey0jTeJA=; b=2zSZQf9o6UpYJ9eX/dzPufzBYrXVNfD5XqllHda3DLhg9nu4sCYW4Poxxn/K+5QpGBoDsThlp LKnBnPTEUMdDj7Dri4sNbXQLoI9d8sPZXL/aAUEw2FfYdqAgMaCHYVy X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Ackerley Tng The dequeue_hugetlb_folio_vma() function currently handles the gbl_chg parameter to determine if a folio can be dequeued based on global page availability. This leaks reservation-specific logic into the dequeueing path. Relocate this logic to alloc_hugetlb_folio() so that dequeue_hugetlb_folio_vma() focuses solely on selecting and dequeuing a folio. In alloc_hugetlb_folio(), only attempt to dequeue a folio if a reservation exists (gbl_chg =3D=3D 0) or if there are available huge pages = in the global pool. No functional change intended. Reviewed-by: James Houghton Acked-by: Oscar Salvador Reviewed-by: Joshua Hahn Signed-off-by: Ackerley Tng Reviewed-by: Gregory Price --- mm/hugetlb.c | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e93c4d2456aa4..7985cfd21a03c 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1319,7 +1319,7 @@ static unsigned long available_huge_pages(struct hsta= te *h) =20 static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h, struct vm_area_struct *vma, - unsigned long address, long gbl_chg) + unsigned long address) { struct folio *folio =3D NULL; struct mempolicy *mpol; @@ -1327,13 +1327,6 @@ static struct folio *dequeue_hugetlb_folio_vma(struc= t hstate *h, nodemask_t *nodemask; int nid; =20 - /* - * gbl_chg=3D=3D1 means the allocation requires a new page that was not - * reserved before. Making sure there's at least one free page. - */ - if (gbl_chg && !available_huge_pages(h)) - goto err; - gfp_mask =3D htlb_alloc_mask(h); nid =3D huge_node(vma, address, gfp_mask, &mpol, &nodemask); =20 @@ -1351,9 +1344,6 @@ static struct folio *dequeue_hugetlb_folio_vma(struct= hstate *h, =20 mpol_cond_put(mpol); return folio; - -err: - return NULL; } =20 #if defined(CONFIG_ARCH_HAS_GIGANTIC_PAGE) && defined(CONFIG_CONTIG_ALLOC) @@ -2923,12 +2913,18 @@ struct folio *alloc_hugetlb_folio(struct vm_area_st= ruct *vma, goto out_uncharge_cgroup_reservation; =20 spin_lock_irq(&hugetlb_lock); + /* - * glb_chg is passed to indicate whether or not a page must be taken - * from the global free pool (global change). gbl_chg =3D=3D 0 indicates - * a reservation exists for the allocation. + * Try to dequeue from the pool if either: + * 1) A reservation exists (gbl_chg =3D=3D 0). + * 2) No reservation exists, but there are unreserved (available) + * pages in the pool; this prefers using pre-allocated pool + * pages over allocating fresh ones from the buddy allocator. */ - folio =3D dequeue_hugetlb_folio_vma(h, vma, addr, gbl_chg); 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Mon, 3 Aug 2026 13:38:04 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Mon, 03 Aug 2026 06:37:59 -0700 Subject: [PATCH v5 2/3] mm: hugetlb: Move mpol interpretation out of alloc_buddy_hugetlb_folio_with_mpol() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260803-hugetlb-mpol-interpretation-v5-2-af2b7089f8a9@google.com> References: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> In-Reply-To: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> To: Alistair Popple , Andrew Morton , Byungchul Park , David Hildenbrand , Gregory Price , Joshua Hahn , Matthew Brost , Muchun Song , Oscar Salvador , Rakie Kim , Ying Huang , Zi Yan , erdemaktas@google.com, fvdl@google.com, jiaqiyan@google.com, jthoughton@google.com, mhocko@kernel.org, michael.roth@amd.com, pasha.tatashin@soleen.com, pbonzini@redhat.com, peterx@redhat.com, pratyush@kernel.org, rick.p.edgecombe@intel.com, rientjes@google.com, roman.gushchin@linux.dev, seanjc@google.com, shakeel.butt@linux.dev, shivankg@amd.com, vannapurve@google.com, yan.y.zhao@intel.com, Jason Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1785764284; l=4762; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=wYqvllJ825+3G1PTvuHSW07dYvdU6Lqe0qHUWN7iPXg=; b=hhdnZtqqlVB1rX6spiHuGLYVsQxCacg57E65NcWdbiU0wvPTL175Kov8PdD4TlSirrYO3htAn 4qQJuOqkg4XBEUhakN6nChqbcwfRaPZo0EJDSqR5FQQpBB20TepPmHo X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Ackerley Tng Move memory policy interpretation out of alloc_buddy_hugetlb_folio_with_mpol() and into alloc_hugetlb_folio() to separate reading and interpretation of memory policy from actual allocation. This will later allow memory policy to be interpreted outside of the process of allocating a hugetlb folio entirely. This opens doors for other callers of the HugeTLB folio allocation function, such as guest_memfd, where memory may not always be mapped and hence may not have an associated vma. Introduce struct mempolicy_interpreted to hold all the components of an interpreted memory policy. Rename alloc_buddy_hugetlb_folio_with_mpol() to alloc_buddy_hugetlb_folio() since the function no longer interprets memory policy. No functional change intended. Reviewed-by: James Houghton Acked-by: Oscar Salvador Signed-off-by: Ackerley Tng --- include/uapi/linux/mempolicy.h | 2 +- mm/hugetlb.c | 54 ++++++++++++++++++++++++++++----------= ---- 2 files changed, 37 insertions(+), 19 deletions(-) diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h index 6c962d866e864..7f6fc9599693b 100644 --- a/include/uapi/linux/mempolicy.h +++ b/include/uapi/linux/mempolicy.h @@ -16,7 +16,7 @@ */ =20 /* Policies */ -enum { +enum mempolicy_mode { MPOL_DEFAULT, MPOL_PREFERRED, MPOL_BIND, diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7985cfd21a03c..3a159de08a0b6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1317,6 +1317,12 @@ static unsigned long available_huge_pages(struct hst= ate *h) return h->free_huge_pages - h->resv_huge_pages; } =20 +struct mempolicy_interpreted { + int nid; + nodemask_t *nodemask; + enum mempolicy_mode mode; +}; + static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h, struct vm_area_struct *vma, unsigned long address) @@ -2138,32 +2144,28 @@ static struct folio *alloc_migrate_hugetlb_folio(st= ruct hstate *h, gfp_t gfp_mas return folio; } =20 -/* - * Use the VMA's mpolicy to allocate a huge page from the buddy. - */ static -struct folio *alloc_buddy_hugetlb_folio_with_mpol(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) +struct folio *alloc_buddy_hugetlb_folio(struct hstate *h, + gfp_t gfp_mask, struct mempolicy_interpreted *mpoli) { struct folio *folio =3D NULL; - struct mempolicy *mpol; - gfp_t gfp_mask =3D htlb_alloc_mask(h); - int nid; - nodemask_t *nodemask; + nodemask_t *nodemask =3D mpoli->nodemask; =20 - nid =3D huge_node(vma, addr, gfp_mask, &mpol, &nodemask); - if (mpol_is_preferred_many(mpol)) { + if (mpoli->mode =3D=3D MPOL_PREFERRED_MANY) { gfp_t gfp =3D gfp_mask & ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); =20 - folio =3D alloc_surplus_hugetlb_folio(h, gfp, nid, nodemask); + folio =3D alloc_surplus_hugetlb_folio(h, gfp, mpoli->nid, + nodemask); =20 /* Fallback to all nodes if page=3D=3DNULL */ nodemask =3D NULL; } =20 - if (!folio) - folio =3D alloc_surplus_hugetlb_folio(h, gfp_mask, nid, nodemask); - mpol_cond_put(mpol); + if (!folio) { + folio =3D alloc_surplus_hugetlb_folio(h, gfp_mask, mpoli->nid, + nodemask); + } + return folio; } =20 @@ -2853,7 +2855,7 @@ struct folio *alloc_hugetlb_folio(struct vm_area_stru= ct *vma, int ret, idx; struct hugetlb_cgroup *h_cg =3D NULL; struct hugetlb_cgroup *h_cg_rsvd =3D NULL; - gfp_t gfp =3D htlb_alloc_mask(h) | __GFP_RETRY_MAYFAIL; + gfp_t gfp =3D htlb_alloc_mask(h); =20 idx =3D hstate_index(h); =20 @@ -2926,8 +2928,24 @@ struct folio *alloc_hugetlb_folio(struct vm_area_str= uct *vma, folio =3D dequeue_hugetlb_folio_vma(h, vma, addr); =20 if (!folio) { + struct mempolicy_interpreted mpoli; + struct mempolicy *mpol; + nodemask_t *nodemask; + int nid; + spin_unlock_irq(&hugetlb_lock); - folio =3D alloc_buddy_hugetlb_folio_with_mpol(h, vma, addr); + nid =3D huge_node(vma, addr, gfp, &mpol, &nodemask); + mpoli =3D (struct mempolicy_interpreted){ + .nid =3D nid, +#ifdef CONFIG_NUMA + .mode =3D mpol ? mpol->mode : MPOL_DEFAULT, +#else + .mode =3D MPOL_DEFAULT, +#endif + .nodemask =3D nodemask, + }; + folio =3D alloc_buddy_hugetlb_folio(h, gfp, &mpoli); + mpol_cond_put(mpol); if (!folio) goto out_uncharge_cgroup; spin_lock_irq(&hugetlb_lock); @@ -2983,7 +3001,7 @@ struct folio *alloc_hugetlb_folio(struct vm_area_stru= ct *vma, } } =20 - ret =3D mem_cgroup_charge_hugetlb(folio, gfp); + ret =3D mem_cgroup_charge_hugetlb(folio, gfp | __GFP_RETRY_MAYFAIL); /* * Unconditionally increment NR_HUGETLB here. If it turns out that * mem_cgroup_charge_hugetlb failed, then immediately free the page and --=20 2.55.0.508.g3f0d502094-goog From nobody Fri Oct 2 08:25:53 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 624A83D7A01 for ; Mon, 3 Aug 2026 13:38:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785764285; cv=none; b=ID3kRfYzvCNgU28C0XFdMB2H4BKhSJjVFnc3DnbBS8eWn85teiBRGWCecLX1e94GIAQdAFLXrhlxIOfd1gpyNuymDXcLjbV/1uwcR8xQfzIEZEFBKKx4STBTZuVQ4qbazOxhzBD49It9IPOlA+AeRBxHJJi9YUNNd4WFsB/KKjg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785764285; c=relaxed/simple; bh=1sczfEuOl5XyE2+dFqSPsBh7HifK/3TttmuhFQr34MA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=RAUGYRs5qqsUS9flqqqza9ddutrkNlJXSmcVYe+73lZz1Gr++5Fsc686MMFZVOySl34lDUPTuDPtxsoePbadQQL39ycsc8QNrbv66A3Ckyb+XHhke+Y+stZd9OLsl7DntdOYngusYUdHQc1aLq2K2LbP+XzPLM+WtzWdKnJ6M8w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OAr+9fs8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OAr+9fs8" Received: by smtp.kernel.org (Postfix) with ESMTPS id 2C152C2BCF6; Mon, 3 Aug 2026 13:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1785764285; bh=1sczfEuOl5XyE2+dFqSPsBh7HifK/3TttmuhFQr34MA=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=OAr+9fs88Eie5X83EVkqf8msca0QFAUS4awl9Z+/gyCptTS+0PPtzO/Xe5udWhr6R N+YCHIMuu041rNUZE2LJ29wC/xgjNk6QnysCXJfnAOrFQkz5eC+kjAjgVebsLRhV06 hS4RRuC4DX7Nqcer2D0IuPIcle1imYrWEfyplyO4lHqkE5acNdKCaUgt+TPOuSCdkb ZvGtfS+01R8N/uzsIlDF/spCFPrZvIOz5ax66Ti0b5j897D2AxgI2XsGqCwiZtDYkl 90MXLyR6wU5cya6A5gPBgAtlcstm0BqNgxHQRa6UMk2VlpttUj1XNfOiY+eI+49cNX p4bRmcXlWCpoQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 112C4C55838; Mon, 3 Aug 2026 13:38:05 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Mon, 03 Aug 2026 06:38:00 -0700 Subject: [PATCH v5 3/3] mm: hugetlb: Move mpol interpretation out of dequeue_hugetlb_folio_vma() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260803-hugetlb-mpol-interpretation-v5-3-af2b7089f8a9@google.com> References: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> In-Reply-To: <20260803-hugetlb-mpol-interpretation-v5-0-af2b7089f8a9@google.com> To: Alistair Popple , Andrew Morton , Byungchul Park , David Hildenbrand , Gregory Price , Joshua Hahn , Matthew Brost , Muchun Song , Oscar Salvador , Rakie Kim , Ying Huang , Zi Yan , erdemaktas@google.com, fvdl@google.com, jiaqiyan@google.com, jthoughton@google.com, mhocko@kernel.org, michael.roth@amd.com, pasha.tatashin@soleen.com, pbonzini@redhat.com, peterx@redhat.com, pratyush@kernel.org, rick.p.edgecombe@intel.com, rientjes@google.com, roman.gushchin@linux.dev, seanjc@google.com, shakeel.butt@linux.dev, shivankg@amd.com, vannapurve@google.com, yan.y.zhao@intel.com, Jason Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1785764284; l=4241; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=mxYJ9ZfIJDNqqNET+i798zl+eMXnvPpSjYi2l1OPxHE=; b=QivN7sN8I31WwiKn12XzM7zIcnCzCJFKMeumY1BlC2xQSYMVmWvVkTmcw5squW1hr8iXtI4B0 wOnsLFdhs81A9khAN94v1qQa86hSPfKdAOJ4qgacYrp7gCr0+NrP8kz X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Ackerley Tng Move memory policy interpretation out of dequeue_hugetlb_folio_vma() and into alloc_hugetlb_folio() to separate reading and interpretation of memory policy from actual allocation. Also rename dequeue_hugetlb_folio_vma() to dequeue_hugetlb_folio_with_mpol() to remove association with vma and to align with alloc_buddy_hugetlb_folio_with_mpol(). This will later allow memory policy to be interpreted outside of the process of allocating a hugetlb folio entirely. This opens doors for other callers of the HugeTLB folio allocation function, such as guest_memfd, where memory may not always be mapped and hence may not have an associated vma. No functional change intended. Signed-off-by: Ackerley Tng Reviewed-by: James Houghton Reviewed-by: Gregory Price (Meta) --- mm/hugetlb.c | 66 +++++++++++++++++++++++++++++---------------------------= ---- 1 file changed, 32 insertions(+), 34 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3a159de08a0b6..a11cb919e00fe 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1323,32 +1323,26 @@ struct mempolicy_interpreted { enum mempolicy_mode mode; }; =20 -static struct folio *dequeue_hugetlb_folio_vma(struct hstate *h, - struct vm_area_struct *vma, - unsigned long address) +static struct folio *dequeue_hugetlb_folio(struct hstate *h, gfp_t gfp_mas= k, + struct mempolicy_interpreted *mpoli) { + nodemask_t *nodemask =3D mpoli->nodemask; struct folio *folio =3D NULL; - struct mempolicy *mpol; - gfp_t gfp_mask; - nodemask_t *nodemask; - int nid; - - gfp_mask =3D htlb_alloc_mask(h); - nid =3D huge_node(vma, address, gfp_mask, &mpol, &nodemask); =20 - if (mpol_is_preferred_many(mpol)) { + if (mpoli->mode =3D=3D MPOL_PREFERRED_MANY) { folio =3D dequeue_hugetlb_folio_nodemask(h, gfp_mask, - nid, nodemask); + mpoli->nid, + nodemask); =20 /* Fallback to all nodes if page=3D=3DNULL */ nodemask =3D NULL; } =20 - if (!folio) + if (!folio) { folio =3D dequeue_hugetlb_folio_nodemask(h, gfp_mask, - nid, nodemask); - - mpol_cond_put(mpol); + mpoli->nid, + nodemask); + } return folio; } =20 @@ -2855,7 +2849,11 @@ struct folio *alloc_hugetlb_folio(struct vm_area_str= uct *vma, int ret, idx; struct hugetlb_cgroup *h_cg =3D NULL; struct hugetlb_cgroup *h_cg_rsvd =3D NULL; + struct mempolicy_interpreted mpoli; gfp_t gfp =3D htlb_alloc_mask(h); + struct mempolicy *mpol; + nodemask_t *nodemask; + int nid; =20 idx =3D hstate_index(h); =20 @@ -2914,6 +2912,18 @@ struct folio *alloc_hugetlb_folio(struct vm_area_str= uct *vma, if (ret) goto out_uncharge_cgroup_reservation; =20 + /* Takes reference on mpol. */ + nid =3D huge_node(vma, addr, gfp, &mpol, &nodemask); + mpoli =3D (struct mempolicy_interpreted){ + .nid =3D nid, +#ifdef CONFIG_NUMA + .mode =3D mpol ? mpol->mode : MPOL_DEFAULT, +#else + .mode =3D MPOL_DEFAULT, +#endif + .nodemask =3D nodemask, + }; + spin_lock_irq(&hugetlb_lock); =20 /* @@ -2925,35 +2935,23 @@ struct folio *alloc_hugetlb_folio(struct vm_area_st= ruct *vma, */ folio =3D NULL; if (!gbl_chg || available_huge_pages(h)) - folio =3D dequeue_hugetlb_folio_vma(h, vma, addr); + folio =3D dequeue_hugetlb_folio(h, gfp, &mpoli); =20 if (!folio) { - struct mempolicy_interpreted mpoli; - struct mempolicy *mpol; - nodemask_t *nodemask; - int nid; - spin_unlock_irq(&hugetlb_lock); - nid =3D huge_node(vma, addr, gfp, &mpol, &nodemask); - mpoli =3D (struct mempolicy_interpreted){ - .nid =3D nid, -#ifdef CONFIG_NUMA - .mode =3D mpol ? mpol->mode : MPOL_DEFAULT, -#else - .mode =3D MPOL_DEFAULT, -#endif - .nodemask =3D nodemask, - }; folio =3D alloc_buddy_hugetlb_folio(h, gfp, &mpoli); - mpol_cond_put(mpol); - if (!folio) + if (!folio) { + mpol_cond_put(mpol); goto out_uncharge_cgroup; + } spin_lock_irq(&hugetlb_lock); list_add(&folio->lru, &h->hugepage_activelist); folio_ref_unfreeze(folio, 1); /* Fall through */ } =20 + mpol_cond_put(mpol); + /* * Either dequeued or buddy-allocated folio needs to add special * mark to the folio when it consumes a global reservation. --=20 2.55.0.508.g3f0d502094-goog