From mboxrd@z Thu Jan 1 00:00:00 1970 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 C5264189910 for ; Tue, 8 Oct 2024 18:20:57 +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=1728411657; cv=none; b=GJaodKZikktSobqowddFVl78heQREPacxEYQxX14LKTGMN9tnQxhh9Db5huOjkuHZUJih0fz2LNzO/e4ZbI0roAjCt1jiEEosHGzn4qOXlnLXp6cwB1UKjYLV12ek797BokgISDsw/WzXV+xzNrY/hhSP7M9iYxgIVwBpYyIxEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728411657; c=relaxed/simple; bh=bOfJV47m5I4ivzO4TmtgeU1KXkoCWt09KtaPmeoSj2M=; h=Date:To:From:Subject:Message-Id; b=iLXbMv3fIrecOT2CqwYhMctjEp50qyktTlKz/A8vJbX7RLMqT/P+LkIVjqgayP7tGyADPuAoP7jSbZWQqLhhpQvtvJBIq88tH+td9EKi5wyEDNo9dt5IIlczDcRlBdPQGUV/xoX+csknCSySk/Ll1X1EomTPCvpaw6cclgUgn1U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=jmSDF8ci; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="jmSDF8ci" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B6FCC4CECF; Tue, 8 Oct 2024 18:20:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1728411657; bh=bOfJV47m5I4ivzO4TmtgeU1KXkoCWt09KtaPmeoSj2M=; h=Date:To:From:Subject:From; b=jmSDF8ciV70qeDIf2Oz1n4YSGbjQTymL5oMTj1mZtfhqzHGRImAzHsLokdvtLCEFV lMyYUbCCa3tU0oY+dMivs5etDJopYblSEoDqFX9BUY8lL+Z/UZd5m5o1EqrUITUMh2 4kHlz7vMxjhySBrb9b9Co/XZmM4Mq3JAmGkk9KJc= Date: Tue, 08 Oct 2024 11:20:56 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,yang@os.amperecomputing.com,willy@infradead.org,will@kernel.org,wangkefeng.wang@huawei.com,vbabka@suse.cz,ryan.roberts@arm.com,peterx@redhat.com,mhocko@suse.com,mark.rutland@arm.com,kirill.shutemov@linux.intel.com,jack@suse.cz,ioworker0@gmail.com,hughd@google.com,david@redhat.com,dave.hansen@linux.intel.com,cl@gentwo.org,catalin.marinas@arm.com,baohua@kernel.org,apopple@nvidia.com,anshuman.khandual@arm.com,aneesh.kumar@kernel.org,dev.jain@arm.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-allocate-thp-on-hugezeropage-wp-fault.patch added to mm-unstable branch Message-Id: <20241008182057.3B6FCC4CECF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm: allocate THP on hugezeropage wp-fault has been added to the -mm mm-unstable branch. Its filename is mm-allocate-thp-on-hugezeropage-wp-fault.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-allocate-thp-on-hugezeropage-wp-fault.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Dev Jain Subject: mm: allocate THP on hugezeropage wp-fault Date: Tue, 8 Oct 2024 11:47:46 +0530 Introduce do_huge_zero_wp_pmd() to handle wp-fault on a hugezeropage and replace it with a PMD-mapped THP. Remember to flush TLB entry corresponding to the hugezeropage. In case of failure, fallback to splitting the PMD. Link: https://lkml.kernel.org/r/20241008061746.285961-3-dev.jain@arm.com Signed-off-by: Dev Jain Acked-by: David Hildenbrand Reviewed-by: Kefeng Wang Cc: Alistair Popple Cc: Aneesh Kumar K.V Cc: Anshuman Khandual Cc: Barry Song Cc: Catalin Marinas Cc: Christoph Lameter Cc: Dave Hansen Cc: Dev Jain Cc: Hugh Dickins Cc: Jan Kara Cc: Kirill A. Shutemov Cc: Lance Yang Cc: Mark Rutland Cc: Matthew Wilcox Cc: Michal Hocko Cc: Peter Xu Cc: Ryan Roberts Cc: Vlastimil Babka Cc: Will Deacon Cc: Yang Shi Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/huge_memory.c | 41 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) --- a/mm/huge_memory.c~mm-allocate-thp-on-hugezeropage-wp-fault +++ a/mm/huge_memory.c @@ -1792,6 +1792,38 @@ unlock: spin_unlock(vmf->ptl); } +static vm_fault_t do_huge_zero_wp_pmd(struct vm_fault *vmf) +{ + unsigned long haddr = vmf->address & HPAGE_PMD_MASK; + struct vm_area_struct *vma = vmf->vma; + struct mmu_notifier_range range; + struct folio *folio; + vm_fault_t ret = 0; + + folio = vma_alloc_anon_folio_pmd(vma, vmf->address); + if (unlikely(!folio)) + return VM_FAULT_FALLBACK; + + mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma->vm_mm, haddr, + haddr + HPAGE_PMD_SIZE); + mmu_notifier_invalidate_range_start(&range); + vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); + if (unlikely(!pmd_same(pmdp_get(vmf->pmd), vmf->orig_pmd))) + goto release; + ret = check_stable_address_space(vma->vm_mm); + if (ret) + goto release; + (void)pmdp_huge_clear_flush(vma, haddr, vmf->pmd); + map_anon_folio_pmd(folio, vmf->pmd, vma, haddr); + goto unlock; +release: + folio_put(folio); +unlock: + spin_unlock(vmf->ptl); + mmu_notifier_invalidate_range_end(&range); + return ret; +} + vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf) { const bool unshare = vmf->flags & FAULT_FLAG_UNSHARE; @@ -1804,8 +1836,15 @@ vm_fault_t do_huge_pmd_wp_page(struct vm vmf->ptl = pmd_lockptr(vma->vm_mm, vmf->pmd); VM_BUG_ON_VMA(!vma->anon_vma, vma); - if (is_huge_zero_pmd(orig_pmd)) + if (is_huge_zero_pmd(orig_pmd)) { + vm_fault_t ret = do_huge_zero_wp_pmd(vmf); + + if (!(ret & VM_FAULT_FALLBACK)) + return ret; + + /* Fallback to splitting PMD if THP cannot be allocated */ goto fallback; + } spin_lock(vmf->ptl); _ Patches currently in -mm which might be from dev.jain@arm.com are mm-abstract-thp-allocation.patch mm-allocate-thp-on-hugezeropage-wp-fault.patch