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 0AB4622DFB1 for ; Tue, 6 May 2025 11:52:53 +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=1746532377; cv=none; b=ohopMDHumkvvqhipKLGjgMpomhM+GOhno5LaIDK/Zk4yHE9IiUsPP2ulVVCXFtGPRbidMSyE66zEEe7/ZHTWWSO8IA2B9N6rowqX3KF9c+r4dz/+v6iCRNu5ctxb3GJuZfep/sYqYUQxpVQBi2x2cfxi7fOIw5dtCUvRoQjohK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746532377; c=relaxed/simple; bh=4Dj8J1B6emEgedZ+BggE2aDkhwBb3aam1vzdhifBmI8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Y7t5MWRCgeerS6eXEfiPPoFecHEZc3LUt3EHPZ9czj7sCNu0jllOGFMQiS9jRZWweovCGr5lriIk6tB4BK1uslWr6li/mMHnlGbFSpclpun9A+hdfspbRkl51RMWZSadP2U46J70P4ML43Fzqz50j/+Fz0FDNtEiDO29Zj9Jrkk= 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 512CF113E; Tue, 6 May 2025 04:52:43 -0700 (PDT) Received: from [10.163.80.199] (unknown [10.163.80.199]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A5A223F58B; Tue, 6 May 2025 04:52:42 -0700 (PDT) Message-ID: <060ce34c-6729-4128-9190-264f7684e299@arm.com> Date: Tue, 6 May 2025 17:22:39 +0530 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 1/3] mm: Call pointers to ptes as ptep To: Lorenzo Stoakes Cc: akpm@linux-foundation.org, Liam.Howlett@oracle.com, vbabka@suse.cz, jannh@google.com, pfalcato@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@redhat.com, peterx@redhat.com, ryan.roberts@arm.com, mingo@kernel.org, libang.li@antgroup.com, maobibo@loongson.cn, zhengqi.arch@bytedance.com, baohua@kernel.org, anshuman.khandual@arm.com, willy@infradead.org, ioworker0@gmail.com, yang@os.amperecomputing.com References: <20250506050056.59250-1-dev.jain@arm.com> <20250506050056.59250-2-dev.jain@arm.com> <5c20ada8-4863-4a33-bb1d-3b5695d0bf66@lucifer.local> Content-Language: en-US From: Dev Jain In-Reply-To: <5c20ada8-4863-4a33-bb1d-3b5695d0bf66@lucifer.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 06/05/25 4:22 pm, Lorenzo Stoakes wrote: > On Tue, May 06, 2025 at 10:30:54AM +0530, Dev Jain wrote: >> Avoid confusion between pte_t* and pte_t data types by appending pointer >> type variables by p. No functional change. > > NIT: 'appending'->'suffixing' and 'by p' -> with p'. Thanks. > >> >> Signed-off-by: Dev Jain > > This looks generally fine, could you fix the nit below however... sorry to > be a pain! > > Thanks! > >> --- >> mm/mremap.c | 28 ++++++++++++++-------------- >> 1 file changed, 14 insertions(+), 14 deletions(-) >> >> diff --git a/mm/mremap.c b/mm/mremap.c >> index 7db9da609c84..1a08a7c3b92f 100644 >> --- a/mm/mremap.c >> +++ b/mm/mremap.c >> @@ -176,7 +176,7 @@ static int move_ptes(struct pagetable_move_control *pmc, >> struct vm_area_struct *vma = pmc->old; >> bool need_clear_uffd_wp = vma_has_uffd_without_event_remap(vma); >> struct mm_struct *mm = vma->vm_mm; >> - pte_t *old_pte, *new_pte, pte; >> + pte_t *old_ptep, *new_ptep, pte; > > While we're at it, can we please move the pte decl to a new line? Mixing > pointers and non-pointers is not great (I refactored it but mremap still > has a bunch of less-than-ideal stuff in it :) Sure. > >> pmd_t dummy_pmdval; >> spinlock_t *old_ptl, *new_ptl; >> bool force_flush = false; >> @@ -211,8 +211,8 @@ static int move_ptes(struct pagetable_move_control *pmc, >> * We don't have to worry about the ordering of src and dst >> * pte locks because exclusive mmap_lock prevents deadlock. >> */ >> - old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl); >> - if (!old_pte) { >> + old_ptep = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl); >> + if (!old_ptep) { >> err = -EAGAIN; >> goto out; >> } >> @@ -223,10 +223,10 @@ static int move_ptes(struct pagetable_move_control *pmc, >> * mmap_lock, so this new_pte page is stable, so there is no need to get >> * pmdval and do pmd_same() check. >> */ >> - new_pte = pte_offset_map_rw_nolock(mm, new_pmd, new_addr, &dummy_pmdval, >> + new_ptep = pte_offset_map_rw_nolock(mm, new_pmd, new_addr, &dummy_pmdval, >> &new_ptl); >> - if (!new_pte) { >> - pte_unmap_unlock(old_pte, old_ptl); >> + if (!new_ptep) { >> + pte_unmap_unlock(old_ptep, old_ptl); >> err = -EAGAIN; >> goto out; >> } >> @@ -235,12 +235,12 @@ static int move_ptes(struct pagetable_move_control *pmc, >> flush_tlb_batched_pending(vma->vm_mm); >> arch_enter_lazy_mmu_mode(); >> >> - for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE, >> - new_pte++, new_addr += PAGE_SIZE) { >> - if (pte_none(ptep_get(old_pte))) >> + for (; old_addr < old_end; old_ptep++, old_addr += PAGE_SIZE, >> + new_ptep++, new_addr += PAGE_SIZE) { >> + if (pte_none(ptep_get(old_ptep))) >> continue; >> >> - pte = ptep_get_and_clear(mm, old_addr, old_pte); >> + pte = ptep_get_and_clear(mm, old_addr, old_ptep); >> /* >> * If we are remapping a valid PTE, make sure >> * to flush TLB before we drop the PTL for the >> @@ -258,7 +258,7 @@ static int move_ptes(struct pagetable_move_control *pmc, >> pte = move_soft_dirty_pte(pte); >> >> if (need_clear_uffd_wp && pte_marker_uffd_wp(pte)) >> - pte_clear(mm, new_addr, new_pte); >> + pte_clear(mm, new_addr, new_ptep); >> else { >> if (need_clear_uffd_wp) { >> if (pte_present(pte)) >> @@ -266,7 +266,7 @@ static int move_ptes(struct pagetable_move_control *pmc, >> else if (is_swap_pte(pte)) >> pte = pte_swp_clear_uffd_wp(pte); >> } >> - set_pte_at(mm, new_addr, new_pte, pte); >> + set_pte_at(mm, new_addr, new_ptep, pte); >> } >> } >> >> @@ -275,8 +275,8 @@ static int move_ptes(struct pagetable_move_control *pmc, >> flush_tlb_range(vma, old_end - len, old_end); >> if (new_ptl != old_ptl) >> spin_unlock(new_ptl); >> - pte_unmap(new_pte - 1); >> - pte_unmap_unlock(old_pte - 1, old_ptl); >> + pte_unmap(new_ptep - 1); >> + pte_unmap_unlock(old_ptep - 1, old_ptl); >> out: >> if (pmc->need_rmap_locks) >> drop_rmap_locks(vma); >> -- >> 2.30.2 >>