From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4D9184CE09 for ; Tue, 2 Jul 2024 08:18:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719908341; cv=none; b=T1b9iJHipv+XbCLBI86b6rwIcon1YGGqbOpmQNkHGhv1iEWAtAupwZDZCkj0vaqUxmOxOFAsdZ9eN53EGkKKC0A8+eqfRT6ns90gDN7IRyiKZkl1jxW9BRzSn6iSDx2sXq8pdJQiDD/6TflBWnsV6eMF/U3enmxBGUBLWPD6VGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719908341; c=relaxed/simple; bh=kkKIITcUg9oP9Wi1l5zsvVb76B8TQyoXp2TAZv6UER8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sRpk0rV9RNN2whGeScxbbpCnOmbvIPXST9MecP+tXEb7zUy1Np3nFRzm9WWU79x3L4clY17lmIRis1Y4oLYjLjFbXI64I5GPQ/EDx04KYlFiDMPaOPakZhEax0psyAxrAfkbbWxtSJaIMIrJRTTpVg2Z6RzwLKEZRhr+0sDEBwg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D40B0339; Tue, 2 Jul 2024 01:19:16 -0700 (PDT) Received: from [10.57.72.41] (unknown [10.57.72.41]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4DCA03F766; Tue, 2 Jul 2024 01:18:50 -0700 (PDT) Message-ID: <507da6d0-77c5-46ca-8351-53b405ecb131@arm.com> Date: Tue, 2 Jul 2024 09:18:48 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] mm: thp: support "THPeligible" semantics for mTHP with anonymous shmem Content-Language: en-GB To: Bang Li , ughd@google.com, akpm@linux-foundation.org Cc: david@redhat.com, wangkefeng.wang@huawei.com, baolin.wang@linux.alibaba.com, ioworker0@gmail.com, ziy@nvidia.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20240702023401.41553-1-libang.li@antgroup.com> From: Ryan Roberts In-Reply-To: <20240702023401.41553-1-libang.li@antgroup.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 02/07/2024 03:34, Bang Li wrote: > After the commit 7fb1b252afb5 ("mm: shmem: add mTHP support for > anonymous shmem"), we can configure different policies through > the multi-size THP sysfs interface for anonymous shmem. But > currently "THPeligible" indicates only whether the mapping is > eligible for allocating THP-pages as well as the THP is PMD > mappable or not for anonymous shmem, we need to support semantics > for mTHP with anonymous shmem similar to those for mTHP with > anonymous memory. > > Signed-off-by: Bang Li > --- > Changes since v1 [1]: > - Put anonymous shmem mthp related logic into > thp_vma_allowable_orders() (per David) > > [1] https://lore.kernel.org/linux-mm/20240628104926.34209-1-libang.li@antgroup.com/ > --- > include/linux/huge_mm.h | 11 +++++++++++ > mm/huge_memory.c | 13 +++++++++---- > mm/shmem.c | 9 +-------- > 3 files changed, 21 insertions(+), 12 deletions(-) > > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > index 212cca384d7e..f87136f38aa1 100644 > --- a/include/linux/huge_mm.h > +++ b/include/linux/huge_mm.h > @@ -267,6 +267,10 @@ unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, > return __thp_vma_allowable_orders(vma, vm_flags, tva_flags, orders); > } > > +unsigned long shmem_allowable_huge_orders(struct inode *inode, > + struct vm_area_struct *vma, pgoff_t index, > + bool global_huge); > + > struct thpsize { > struct kobject kobj; > struct list_head node; > @@ -460,6 +464,13 @@ static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, > return 0; > } > > +static inline unsigned long shmem_allowable_huge_orders(struct inode *inode, > + struct vm_area_struct *vma, pgoff_t index, > + bool global_huge) > +{ > + return 0; > +} > + > #define transparent_hugepage_flags 0UL > > #define thp_get_unmapped_area NULL > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index c7ce28f6b7f3..ea377bb4af91 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -151,10 +151,15 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, > * Must be done before hugepage flags check since shmem has its > * own flags. > */ > - if (!in_pf && shmem_file(vma->vm_file)) > - return shmem_is_huge(file_inode(vma->vm_file), vma->vm_pgoff, > - !enforce_sysfs, vma->vm_mm, vm_flags) > - ? orders : 0; > + if (!in_pf && shmem_file(vma->vm_file)) { > + bool global_huge = shmem_is_huge(file_inode(vma->vm_file), vma->vm_pgoff, > + !enforce_sysfs, vma->vm_mm, vm_flags); > + > + if (!vma_is_anon_shmem(vma)) > + return global_huge? orders : 0; nit: missing space before '?' > + return shmem_allowable_huge_orders(file_inode(vma->vm_file), > + vma, vma->vm_pgoff, global_huge); What's the rationale for splitting these functions into shmem_is_huge() and shmem_allowable_huge_orders()? Why not just have a single shmem_allowable_huge_orders() that tells you the answer? > + } > > if (!vma_is_anonymous(vma)) { > /* > diff --git a/mm/shmem.c b/mm/shmem.c > index d495c0701a83..aa85df9c662a 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -1622,7 +1622,7 @@ static gfp_t limit_gfp_mask(gfp_t huge_gfp, gfp_t limit_gfp) > } > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > -static unsigned long shmem_allowable_huge_orders(struct inode *inode, > +unsigned long shmem_allowable_huge_orders(struct inode *inode, > struct vm_area_struct *vma, pgoff_t index, > bool global_huge) > { > @@ -1707,13 +1707,6 @@ static unsigned long shmem_suitable_orders(struct inode *inode, struct vm_fault > return orders; > } > #else > -static unsigned long shmem_allowable_huge_orders(struct inode *inode, > - struct vm_area_struct *vma, pgoff_t index, > - bool global_huge) > -{ > - return 0; > -} > - > static unsigned long shmem_suitable_orders(struct inode *inode, struct vm_fault *vmf, > struct address_space *mapping, pgoff_t index, > unsigned long orders)