From patchwork Thu Jun 18 01:15:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 11611103 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 98E7092A for ; Thu, 18 Jun 2020 01:16:37 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 615F0221FB for ; Thu, 18 Jun 2020 01:16:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 615F0221FB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9549B6B000C; Wed, 17 Jun 2020 21:16:36 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 904E76B000D; Wed, 17 Jun 2020 21:16:36 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7F49E6B000E; Wed, 17 Jun 2020 21:16:36 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0209.hostedemail.com [216.40.44.209]) by kanga.kvack.org (Postfix) with ESMTP id 66C3F6B000C for ; Wed, 17 Jun 2020 21:16:36 -0400 (EDT) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 1ED0A8245571 for ; Thu, 18 Jun 2020 01:16:36 +0000 (UTC) X-FDA: 76940567592.23.wave44_06131ae26e0c Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin23.hostedemail.com (Postfix) with ESMTP id E48E237604 for ; Thu, 18 Jun 2020 01:16:35 +0000 (UTC) X-Spam-Summary: 2,0,0,8ccdb1a881bbcb04,d41d8cd98f00b204,anshuman.khandual@arm.com,,RULES_HIT:2:41:69:355:379:541:800:960:966:968:973:988:989:1260:1261:1345:1359:1431:1437:1535:1730:1747:1777:1792:1963:2196:2198:2199:2200:2393:2559:2562:2693:2890:2898:3138:3139:3140:3141:3142:3354:3740:3865:3866:3867:3868:3870:3871:4042:4050:4119:4321:4385:5007:6117:6261:6742:8603:8634:8784:8957:9036:10004:11026:11232:11233:11473:11658:11914:12043:12291:12296:12297:12438:12555:12683:12895:12986:13161:13229:13255:14096:14394:21080:21433:21450:21451:21627:21990:30001:30054:30070,0,RBL:217.140.110.172:@arm.com:.lbl8.mailshell.net-64.100.201.201 62.2.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: wave44_06131ae26e0c X-Filterd-Recvd-Size: 8800 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf23.hostedemail.com (Postfix) with ESMTP for ; Thu, 18 Jun 2020 01:16:35 +0000 (UTC) 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 BB8A912FC; Wed, 17 Jun 2020 18:16:34 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.80.176]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 20DE83F6CF; Wed, 17 Jun 2020 18:16:29 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mark Rutland , Steve Capper , David Hildenbrand , Yu Zhao , Hsin-Yi Wang , Thomas Gleixner , Andrew Morton , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH V3 (RESEND) 3/3] arm64/mm: Enable vmem_altmap support for vmemmap mappings Date: Thu, 18 Jun 2020 06:45:30 +0530 Message-Id: <1592442930-9380-4-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1592442930-9380-1-git-send-email-anshuman.khandual@arm.com> References: <1592442930-9380-1-git-send-email-anshuman.khandual@arm.com> X-Rspamd-Queue-Id: E48E237604 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Device memory ranges when getting hot added into ZONE_DEVICE, might require their vmemmap mapping's backing memory to be allocated from their own range instead of consuming system memory. This prevents large system memory usage for potentially large device memory ranges. Device driver communicates this request via vmem_altmap structure. Architecture needs to take this request into account while creating and tearing down vemmmap mappings. This enables vmem_altmap support in vmemmap_populate() and vmemmap_free() which includes vmemmap_populate_basepages() used for ARM64_16K_PAGES and ARM64_64K_PAGES configs. Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Steve Capper Cc: David Hildenbrand Cc: Yu Zhao Cc: Hsin-Yi Wang Cc: Thomas Gleixner Cc: Andrew Morton Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Tested-by: Jia He Signed-off-by: Anshuman Khandual Reviewed-by: Catalin Marinas --- arch/arm64/mm/mmu.c | 58 +++++++++++++++++++++++++++++---------------- 1 file changed, 38 insertions(+), 20 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 7ca21adb4412..f2ad5b94a235 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -759,15 +759,20 @@ int kern_addr_valid(unsigned long addr) } #ifdef CONFIG_MEMORY_HOTPLUG -static void free_hotplug_page_range(struct page *page, size_t size) +static void free_hotplug_page_range(struct page *page, size_t size, + struct vmem_altmap *altmap) { - WARN_ON(PageReserved(page)); - free_pages((unsigned long)page_address(page), get_order(size)); + if (altmap) { + vmem_altmap_free(altmap, size >> PAGE_SHIFT); + } else { + WARN_ON(PageReserved(page)); + free_pages((unsigned long)page_address(page), get_order(size)); + } } static void free_hotplug_pgtable_page(struct page *page) { - free_hotplug_page_range(page, PAGE_SIZE); + free_hotplug_page_range(page, PAGE_SIZE, NULL); } static bool pgtable_range_aligned(unsigned long start, unsigned long end, @@ -790,7 +795,8 @@ static bool pgtable_range_aligned(unsigned long start, unsigned long end, } static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { pte_t *ptep, pte; @@ -804,12 +810,14 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, pte_clear(&init_mm, addr, ptep); flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) - free_hotplug_page_range(pte_page(pte), PAGE_SIZE); + free_hotplug_page_range(pte_page(pte), + PAGE_SIZE, altmap); } while (addr += PAGE_SIZE, addr < end); } static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; pmd_t *pmdp, pmd; @@ -832,16 +840,17 @@ static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr, flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) free_hotplug_page_range(pmd_page(pmd), - PMD_SIZE); + PMD_SIZE, altmap); continue; } WARN_ON(!pmd_table(pmd)); - unmap_hotplug_pte_range(pmdp, addr, next, free_mapped); + unmap_hotplug_pte_range(pmdp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; pud_t *pudp, pud; @@ -864,16 +873,17 @@ static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr, flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) free_hotplug_page_range(pud_page(pud), - PUD_SIZE); + PUD_SIZE, altmap); continue; } WARN_ON(!pud_table(pud)); - unmap_hotplug_pmd_range(pudp, addr, next, free_mapped); + unmap_hotplug_pmd_range(pudp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr, - unsigned long end, bool free_mapped) + unsigned long end, bool free_mapped, + struct vmem_altmap *altmap) { unsigned long next; p4d_t *p4dp, p4d; @@ -886,16 +896,24 @@ static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr, continue; WARN_ON(!p4d_present(p4d)); - unmap_hotplug_pud_range(p4dp, addr, next, free_mapped); + unmap_hotplug_pud_range(p4dp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } static void unmap_hotplug_range(unsigned long addr, unsigned long end, - bool free_mapped) + bool free_mapped, struct vmem_altmap *altmap) { unsigned long next; pgd_t *pgdp, pgd; + /* + * altmap can only be used as vmemmap mapping backing memory. + * In case the backing memory itself is not being freed, then + * altmap is irrelevant. Warn about this inconsistency when + * encountered. + */ + WARN_ON(!free_mapped && altmap); + do { next = pgd_addr_end(addr, end); pgdp = pgd_offset_k(addr); @@ -904,7 +922,7 @@ static void unmap_hotplug_range(unsigned long addr, unsigned long end, continue; WARN_ON(!pgd_present(pgd)); - unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped); + unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped, altmap); } while (addr = next, addr < end); } @@ -1068,7 +1086,7 @@ static void free_empty_tables(unsigned long addr, unsigned long end, int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { - return vmemmap_populate_basepages(start, end, node, NULL); + return vmemmap_populate_basepages(start, end, node, altmap); } #else /* !ARM64_SWAPPER_USES_SECTION_MAPS */ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, @@ -1101,7 +1119,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, void *p = NULL; p = vmemmap_alloc_block_buf(PMD_SIZE, node, - NULL, false); + altmap, false); if (!p) return -ENOMEM; @@ -1119,7 +1137,7 @@ void vmemmap_free(unsigned long start, unsigned long end, #ifdef CONFIG_MEMORY_HOTPLUG WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END)); - unmap_hotplug_range(start, end, true); + unmap_hotplug_range(start, end, true, altmap); free_empty_tables(start, end, VMEMMAP_START, VMEMMAP_END); #endif } @@ -1410,7 +1428,7 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size) WARN_ON(pgdir != init_mm.pgd); WARN_ON((start < PAGE_OFFSET) || (end > PAGE_END)); - unmap_hotplug_range(start, end, false); + unmap_hotplug_range(start, end, false, NULL); free_empty_tables(start, end, PAGE_OFFSET, PAGE_END); }