From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 8DC42446048 for ; Wed, 15 Jul 2026 18:38:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784140689; cv=none; b=fR8Y/++R22DxUe9diC8+6Z4lY+Ym/nsx9QouzDYFdOPMumpBvbRAbUCXC4wqdkOhVWIxEBIenWtSrUUpeQHisUzXkAwxqi8WT8QVg6Ub4IQIEJI1lyJQAz2TXwJ+r3tdCZ8u6NqThXCYQmxx4JBwU+Ui8CaZtqim+wGQF4wZiww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784140689; c=relaxed/simple; bh=iecRMJsbLidYT6OodnLQO3p+tolNHM5n/uZDVan2S7I=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=GKqWf/gk8KsNO7o3VKNWTgZ5Q5UetQQNNDLZ85ZlJK2NktCjZof1YhYKU3MHKc2xlGAGdecCXlj+8dgAcCX+h40Z1Ah78ZNzwYWrkr+t9OSvqYBeVohsekjgy8W9Z/aw9wgDVzji67EAbHcTbmOCF5ZYGGQTKT/P+GULfrmCIO8= 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=R6YsU9y3; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="R6YsU9y3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECA981F000E9; Wed, 15 Jul 2026 18:37:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1784140680; bh=MVD5YICoFs6IGZko2faFmBTnBcS21tFoTzk2EZjj06c=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=R6YsU9y3n0TDYpeduksymjcvij1ta9ZUFduBjNE7KPDuG5FCrySIN/Cl0MsGX6Z/k DmTqgFlF9pAO0Rsv439GGi7L1XAUCT2c26cG8ZSzZlC/9K6gGkhbfaXOdFc2lrUQO0 LLG3nqzkh3F0SkMWkSaLYY9twTc7K23pSBMbE8OE= Date: Wed, 15 Jul 2026 11:37:59 -0700 From: Andrew Morton To: Wen Jiang Cc: catalin.marinas@arm.com, linux-mm@kvack.org, urezki@gmail.com, will@kernel.org, Xueyuan.chen21@gmail.com, ajd@linux.ibm.com, anshuman.khandual@arm.com, david@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, rppt@kernel.org, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, Wen Jiang Subject: Re: [PATCH v7 0/7] mm/vmalloc: Speed up ioremap, vmalloc and vmap with contiguous memory Message-Id: <20260715113759.74d68fef26f1df0c6bbcc85c@linux-foundation.org> In-Reply-To: <20260715120813.3609949-1-jiangwen6@xiaomi.com> References: <20260715120813.3609949-1-jiangwen6@xiaomi.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 15 Jul 2026 20:08:06 +0800 Wen Jiang wrote: > This patchset accelerates ioremap, vmalloc, and vmap when the memory > is physically fully or partially contiguous. Two techniques are used: Thanks, I've updated mm.git's mm-unstable branch to this version. > Changes since v6: > - Add a clarifying comment about the reuse of hugetlb helpers > by non-hugetlbfs(vmalloc) mm code (patch 1) > - Expand the arm64/vmalloc commit message and comment to clarify that > multi-CONT_PTE_SIZE values are vmalloc mapping spans, not HugeTLB > hstate sizes (patch 2) > - Move the local steps variable change in vmap_pte_range() into the > vmap_set_ptes() extraction patch (patch 3) > - Propagate vmap_pages_pte_range() errors through the upper > vmap_pages_*() levels instead of returning -ENOMEM for all failures > (patch 4) > - Add a preparatory vm_shift() helper patch before the batching patch > (patch 5) > - Guard the PFN alignment clamp in get_vmap_batch_order() against PFN 0 > before calling __ffs() (patch 6) > - Fix kmsan_vmap_pages_range_noflush() indentation in the batching path > (patch 6) Here's how v7 altered mm.git: arch/arm64/include/asm/vmalloc.h | 2 + arch/arm64/mm/hugetlbpage.c | 5 ++++ mm/vmalloc.c | 31 ++++++++++++++++------------- 3 files changed, 25 insertions(+), 13 deletions(-) --- a/arch/arm64/include/asm/vmalloc.h~b +++ a/arch/arm64/include/asm/vmalloc.h @@ -29,6 +29,8 @@ static inline unsigned long arch_vmap_pt * If the block is at least CONT_PTE_SIZE in size, and is naturally * aligned in both virtual and physical space, then we can pte-map the * block using the PTE_CONT bit for more efficient use of the TLB. + * The returned mapping size may cover multiple CONT_PTE_SIZE blocks, + * capped below PMD_SIZE. */ if (max_page_shift < CONT_PTE_SHIFT) return PAGE_SIZE; --- a/arch/arm64/mm/hugetlbpage.c~b +++ a/arch/arm64/mm/hugetlbpage.c @@ -94,6 +94,11 @@ static int find_num_contig(struct mm_str return CONT_PTES; } +/* + * num_contig_ptes(), set_huge_pte_at() and arch_make_huge_pte() can be + * used by non-hugetlbfs(vmalloc) mm code to set multiple huge mappings + * at the PTE level. + */ static inline int num_contig_ptes(unsigned long size, size_t *pgsize) { int contig_ptes = 1; --- a/mm/vmalloc.c~b +++ a/mm/vmalloc.c @@ -616,6 +616,7 @@ static int vmap_pages_pmd_range(pud_t *p { pmd_t *pmd; unsigned long next; + int err; pmd = pmd_alloc_track(&init_mm, pud, addr, mask); if (!pmd) @@ -642,8 +643,9 @@ static int vmap_pages_pmd_range(pud_t *p } } - if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask, shift)) - return -ENOMEM; + err = vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask, shift); + if (err) + return err; } while (pmd++, addr = next, addr != end); return 0; } @@ -654,14 +656,16 @@ static int vmap_pages_pud_range(p4d_t *p { pud_t *pud; unsigned long next; + int err; pud = pud_alloc_track(&init_mm, p4d, addr, mask); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); - if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask, shift)) - return -ENOMEM; + err = vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask, shift); + if (err) + return err; } while (pud++, addr = next, addr != end); return 0; } @@ -672,14 +676,16 @@ static int vmap_pages_p4d_range(pgd_t *p { p4d_t *p4d; unsigned long next; + int err; p4d = p4d_alloc_track(&init_mm, pgd, addr, mask); if (!p4d) return -ENOMEM; do { next = p4d_addr_end(addr, end); - if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask, shift)) - return -ENOMEM; + err = vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask, shift); + if (err) + return err; } while (p4d++, addr = next, addr != end); return 0; } @@ -3591,6 +3597,7 @@ static inline unsigned int vm_shift(pgpr static inline int get_vmap_batch_order(struct page **pages, pgprot_t prot, unsigned int max_steps, unsigned int idx) { + unsigned long pfn; unsigned int nr_contig; int order; @@ -3602,9 +3609,11 @@ static inline int get_vmap_batch_order(s return 0; order = ilog2(nr_contig); + pfn = page_to_pfn(pages[idx]); /* Limit order by pfn alignment */ - order = min_t(int, order, __ffs(page_to_pfn(pages[idx]))); + if (pfn > 0) + order = min_t(int, order, __ffs(pfn)); if (vm_shift(prot, PAGE_SIZE << order) == PAGE_SHIFT) return 0; @@ -3621,7 +3630,7 @@ static int vmap_pages_range_batched(unsi int err; err = kmsan_vmap_pages_range_noflush(addr, end, prot, pages, - PAGE_SHIFT, GFP_KERNEL); + PAGE_SHIFT, GFP_KERNEL); if (err) goto out; @@ -4199,11 +4208,7 @@ void *__vmalloc_node_range_noprof(unsign * supporting them. */ - if (arch_vmap_pmd_supported(prot) && size >= PMD_SIZE) - shift = PMD_SHIFT; - else - shift = arch_vmap_pte_supported_shift(size); - + shift = vm_shift(prot, size); align = max(original_align, 1UL << shift); } _