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 97D4BA95E for ; Fri, 4 Apr 2025 04:54:26 +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=1743742469; cv=none; b=N8kS/Ijz21rjXUCF6bhR/q6oqCS8znvqFrqghmJJPGNnxoDQPZJ1AxmCfvXDAZN+f6XKWS3d7DsdUpeNayfIEDwEaFctRX7eVd/suTKEQ/MdiPvCq5bZ+I2GY26L6dqzsj8OMNaJwpZLUixdEOQXA6WG/bDI0K6n6E0cpW36nSY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743742469; c=relaxed/simple; bh=DVsGWBffIxs5oGnbNeh2kPBlbJNcw8YtrJF5Mx0qJaU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YlSQQCvwMml+ZoNLrBX9A+PyHV2WGBuVBZpsP/4mTh0RLJcQI3U3TKRuu28TWW8NdVE0Br2BPGDptjCgUwRBEg2eZQtQw9ABfnIJSg7+hUJ2WN63kpVV2xhwOaXc3Jo1yUD0oolM83ZvXSe3xN6pYIZONnwh9xm5t2XGjoc66DQ= 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 3AE2A1516; Thu, 3 Apr 2025 21:54:28 -0700 (PDT) Received: from [10.162.40.17] (a077893.blr.arm.com [10.162.40.17]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E5A633F59E; Thu, 3 Apr 2025 21:54:20 -0700 (PDT) Message-ID: <39d4d1d4-3d22-4d31-bfc6-1d583e9d3f9b@arm.com> Date: Fri, 4 Apr 2025 10:24:17 +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 v3 10/11] mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes To: Ryan Roberts , Catalin Marinas , Will Deacon , Pasha Tatashin , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , David Hildenbrand , "Matthew Wilcox (Oracle)" , Mark Rutland , Alexandre Ghiti , Kevin Brodsky Cc: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20250304150444.3788920-1-ryan.roberts@arm.com> <20250304150444.3788920-11-ryan.roberts@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20250304150444.3788920-11-ryan.roberts@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/4/25 20:34, Ryan Roberts wrote: > Wrap vmalloc's pte table manipulation loops with > arch_enter_lazy_mmu_mode() / arch_leave_lazy_mmu_mode(). This provides > the arch code with the opportunity to optimize the pte manipulations. > > Note that vmap_pfn() already uses lazy mmu mode since it delegates to > apply_to_page_range() which enters lazy mmu mode for both user and > kernel mappings. > > These hooks will shortly be used by arm64 to improve vmalloc > performance. > > Signed-off-by: Ryan Roberts > --- > mm/vmalloc.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 6111ce900ec4..b63ca0b7dd40 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -104,6 +104,9 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, > pte = pte_alloc_kernel_track(pmd, addr, mask); > if (!pte) > return -ENOMEM; > + > + arch_enter_lazy_mmu_mode(); > + > do { > if (unlikely(!pte_none(ptep_get(pte)))) { > if (pfn_valid(pfn)) { > @@ -127,6 +130,8 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, > set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); > pfn++; > } while (pte += PFN_DOWN(size), addr += size, addr != end); > + > + arch_leave_lazy_mmu_mode(); > *mask |= PGTBL_PTE_MODIFIED; > return 0; > } > @@ -354,6 +359,8 @@ static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, > unsigned long size = PAGE_SIZE; > > pte = pte_offset_kernel(pmd, addr); > + arch_enter_lazy_mmu_mode(); > + > do { > #ifdef CONFIG_HUGETLB_PAGE > size = arch_vmap_pte_range_unmap_size(addr, pte); > @@ -370,6 +377,8 @@ static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, > ptent = ptep_get_and_clear(&init_mm, addr, pte); > WARN_ON(!pte_none(ptent) && !pte_present(ptent)); > } while (pte += (size >> PAGE_SHIFT), addr += size, addr != end); > + > + arch_leave_lazy_mmu_mode(); > *mask |= PGTBL_PTE_MODIFIED; > } > > @@ -515,6 +524,9 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr, > pte = pte_alloc_kernel_track(pmd, addr, mask); > if (!pte) > return -ENOMEM; > + > + arch_enter_lazy_mmu_mode(); > + > do { > struct page *page = pages[*nr]; > > @@ -528,6 +540,8 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr, > set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); > (*nr)++; > } while (pte++, addr += PAGE_SIZE, addr != end); > + > + arch_leave_lazy_mmu_mode(); > *mask |= PGTBL_PTE_MODIFIED; > return 0; > } Reviewed-by: Anshuman Khandual