From nobody Wed Dec 17 08:57:19 2025 Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) (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 AC7A618EAB for ; Tue, 13 May 2025 06:57:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747119443; cv=none; b=jK5Gsi81thgwOIDbZjVkr9mHBN3rkW9/NQVCcI0gxiwegMUxF3VA7wVH1EXqFeJHNnJjsNotSBNZEUJoRCMVGvnsRBgbUttQ/DE8PgCmyZ/iYl4/g+Snl8wn6sxADdjc+u/pOWxsfWgNis3DvRECFBaTgdR2T06oeuxHampoj4A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747119443; c=relaxed/simple; bh=wWBSbQEhRhPMzGf67h4+e4/npWtlFLmds1lYZF9ydfU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=GlayXwGfKMTDjDV7ypqz+YuUTxhXSmOjxdnU9uXGOaKBYBIsbBqYfpEn8o+ib0fT6b7IGa1WWJaVK0UuVyMYpXBHtE4LlcOivp3sGrZeGM/1eBKdIInwsqQ2XaJzS4f5eoTQUnUzrdeBKo2WMHtJ2B7Z7x5Juwsh3qci7ig/Ptg= 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=QEXSuvJO; arc=none smtp.client-ip=115.124.30.133 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="QEXSuvJO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1747119435; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=edxi2BtbIftkD9Lsw4c9tFqAnSMnCehdjxij2qYlJH4=; b=QEXSuvJOmCeruRXV9rWKcRYZ9EPxPPdgX47DbvnUDfZixpJhvVluHYvS455Eqhd7aIBseGI90rkeluQd/MfsgpdCFqB2IobeXuiOeBKW5d1PVTOfhiUDE95OQLr7TTte9pyfvxo6FJBst2RPGboRER8wuB7XXM5X63kySglRbKA= Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0WaVI5CS_1747119433 cluster:ay36) by smtp.aliyun-inc.com; Tue, 13 May 2025 14:57:14 +0800 From: Baolin Wang To: akpm@linux-foundation.org, david@redhat.com Cc: lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, ziy@nvidia.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH] mm: khugepaged: decouple SHMEM and file folios' collapse Date: Tue, 13 May 2025 14:56:35 +0800 Message-ID: X-Mailer: git-send-email 2.43.5 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" Originally, the file pages collapse was intended for tmpfs/shmem to merge into THP in the background. However, now not only tmpfs/shmem can support large folios, but some other file systems (such as XFS, erofs ...) also support large folios. Therefore, it is time to decouple the support of file folios collapse from SHMEM. Signed-off-by: Baolin Wang Acked-by: David Hildenbrand --- Changes from RFC: - Add acked tag from David. Thanks. - Remove CONFIG_SHMEM in khugepaged.h file. --- include/linux/khugepaged.h | 8 -------- mm/Kconfig | 2 +- mm/khugepaged.c | 13 ++----------- 3 files changed, 3 insertions(+), 20 deletions(-) diff --git a/include/linux/khugepaged.h b/include/linux/khugepaged.h index 1f46046080f5..b8d69cfbb58b 100644 --- a/include/linux/khugepaged.h +++ b/include/linux/khugepaged.h @@ -15,16 +15,8 @@ extern void khugepaged_enter_vma(struct vm_area_struct *= vma, unsigned long vm_flags); extern void khugepaged_min_free_kbytes_update(void); extern bool current_is_khugepaged(void); -#ifdef CONFIG_SHMEM extern int collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long add= r, bool install_pmd); -#else -static inline int collapse_pte_mapped_thp(struct mm_struct *mm, - unsigned long addr, bool install_pmd) -{ - return 0; -} -#endif =20 static inline void khugepaged_fork(struct mm_struct *mm, struct mm_struct = *oldmm) { diff --git a/mm/Kconfig b/mm/Kconfig index d4fd40f56178..79237842f7e2 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -898,7 +898,7 @@ config THP_SWAP =20 config READ_ONLY_THP_FOR_FS bool "Read-only THP for filesystems (EXPERIMENTAL)" - depends on TRANSPARENT_HUGEPAGE && SHMEM + depends on TRANSPARENT_HUGEPAGE =20 help Allow khugepaged to put read-only file-backed pages in THP. diff --git a/mm/khugepaged.c b/mm/khugepaged.c index ebcd7c8a4b44..cdf5a581368b 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1464,7 +1464,6 @@ static void collect_mm_slot(struct khugepaged_mm_slot= *mm_slot) } } =20 -#ifdef CONFIG_SHMEM /* folio must be locked, and mmap_lock must be held */ static int set_huge_pmd(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmdp, struct folio *folio, struct page *page) @@ -2353,14 +2352,6 @@ static int hpage_collapse_scan_file(struct mm_struct= *mm, unsigned long addr, trace_mm_khugepaged_scan_file(mm, folio, file, present, swap, result); return result; } -#else -static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long ad= dr, - struct file *file, pgoff_t start, - struct collapse_control *cc) -{ - BUILD_BUG(); -} -#endif =20 static unsigned int khugepaged_scan_mm_slot(unsigned int pages, int *resul= t, struct collapse_control *cc) @@ -2436,7 +2427,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned = int pages, int *result, VM_BUG_ON(khugepaged_scan.address < hstart || khugepaged_scan.address + HPAGE_PMD_SIZE > hend); - if (IS_ENABLED(CONFIG_SHMEM) && !vma_is_anonymous(vma)) { + if (!vma_is_anonymous(vma)) { struct file *file =3D get_file(vma->vm_file); pgoff_t pgoff =3D linear_page_index(vma, khugepaged_scan.address); @@ -2782,7 +2773,7 @@ int madvise_collapse(struct vm_area_struct *vma, stru= ct vm_area_struct **prev, mmap_assert_locked(mm); memset(cc->node_load, 0, sizeof(cc->node_load)); nodes_clear(cc->alloc_nmask); - if (IS_ENABLED(CONFIG_SHMEM) && !vma_is_anonymous(vma)) { + if (!vma_is_anonymous(vma)) { struct file *file =3D get_file(vma->vm_file); pgoff_t pgoff =3D linear_page_index(vma, addr); =20 --=20 2.43.5