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 487B3C4167B for ; Mon, 11 Dec 2023 16:17:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D3DE26B014F; Mon, 11 Dec 2023 11:17:25 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CEDA76B0150; Mon, 11 Dec 2023 11:17:25 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB55F6B0151; Mon, 11 Dec 2023 11:17:25 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id A8A026B014F for ; Mon, 11 Dec 2023 11:17:25 -0500 (EST) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 6FD361207C9 for ; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 635D31A001C X-Rspam-User: X-Stat-Signature: xeretza7ihcaab9ei97e9eokwxexmd8b X-Rspamd-Server: rspam01 X-HE-Tag: 1702311443-770548 X-HE-Meta: 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 pUHY1IkF 0VxKUPWZXIyFlCKgepRQX3ZA68XGhZ162or4ouIJ+aUPqiyDdnkm6OpNn8BK/a8NvVy6zO/dMeFeUGixXr7VxN+ua07vePI5MctIuA+u2Q60TF6AfPW9XK5+c9hhXTDOU1y3T2IS3nzdga5/thUmlVvUg1GtOkwayf+Tar13fxZX9SMLVN+n+MPZs1d3MkReisal+cRC1Jrt6Cnrf7z7sqGL65lM2JZqHPpSZHP6WnZsnTXg7Bd3Ik10qUBiplKVOC9n0D0kytgOBx3FLC3VQZdngnccKTtN+94KoVmhITztyWUM= 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 11/12/2023 15:56, David Hildenbrand wrote: > hugetlb rmap handling differs quite a lot from "ordinary" rmap code. > For example, hugetlb currently only supports entire mappings, and treats > any mapping as mapped using a single "logical PTE". Let's move it out > of the way so we can overhaul our "ordinary" rmap. > implementation/interface. > > Right now we're using page_dup_file_rmap() in some cases where "ordinary" > rmap code would have used page_add_file_rmap(). So let's introduce and > use hugetlb_add_file_rmap() instead. We won't be adding a > "hugetlb_dup_file_rmap()" functon for the fork() case, as it would be > doing the same: "dup" is just an optimization for "add". > > What remains is a single page_dup_file_rmap() call in fork() code. > > Reviewed-by: Yin Fengwei > Signed-off-by: David Hildenbrand Reviewed-by: Ryan Roberts > --- > include/linux/rmap.h | 7 +++++++ > mm/hugetlb.c | 6 +++--- > mm/migrate.c | 2 +- > 3 files changed, 11 insertions(+), 4 deletions(-) > > diff --git a/include/linux/rmap.h b/include/linux/rmap.h > index d85bd1d4de04..91178d1aa028 100644 > --- a/include/linux/rmap.h > +++ b/include/linux/rmap.h > @@ -213,6 +213,13 @@ void hugetlb_add_anon_rmap(struct folio *, struct vm_area_struct *, > void hugetlb_add_new_anon_rmap(struct folio *, struct vm_area_struct *, > unsigned long address); > > +static inline void hugetlb_add_file_rmap(struct folio *folio) > +{ > + VM_WARN_ON_FOLIO(folio_test_anon(folio), folio); > + > + atomic_inc(&folio->_entire_mapcount); > +} > + > static inline void hugetlb_remove_rmap(struct folio *folio) > { > atomic_dec(&folio->_entire_mapcount); > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index ef48ae673890..57e898187931 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -5408,7 +5408,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, > * sleep during the process. > */ > if (!folio_test_anon(pte_folio)) { > - page_dup_file_rmap(&pte_folio->page, true); > + hugetlb_add_file_rmap(pte_folio); > } else if (page_try_dup_anon_rmap(&pte_folio->page, > true, src_vma)) { > pte_t src_pte_old = entry; > @@ -6279,7 +6279,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, > if (anon_rmap) > hugetlb_add_new_anon_rmap(folio, vma, haddr); > else > - page_dup_file_rmap(&folio->page, true); > + hugetlb_add_file_rmap(folio); > new_pte = make_huge_pte(vma, &folio->page, ((vma->vm_flags & VM_WRITE) > && (vma->vm_flags & VM_SHARED))); > /* > @@ -6730,7 +6730,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, > goto out_release_unlock; > > if (folio_in_pagecache) > - page_dup_file_rmap(&folio->page, true); > + hugetlb_add_file_rmap(folio); > else > hugetlb_add_new_anon_rmap(folio, dst_vma, dst_addr); > > diff --git a/mm/migrate.c b/mm/migrate.c > index 4cb849fa0dd2..de9d94b99ab7 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -252,7 +252,7 @@ static bool remove_migration_pte(struct folio *folio, > hugetlb_add_anon_rmap(folio, vma, pvmw.address, > rmap_flags); > else > - page_dup_file_rmap(new, true); > + hugetlb_add_file_rmap(folio); > set_huge_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte, > psize); > } else