From patchwork Wed Jul 15 07:19:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenyu Ye X-Patchwork-Id: 11664353 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 00334138C for ; Wed, 15 Jul 2020 07:20:17 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BD8E5206D5 for ; Wed, 15 Jul 2020 07:20:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD8E5206D5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4F0D28D0002; Wed, 15 Jul 2020 03:20:10 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 1E3B98D0006; Wed, 15 Jul 2020 03:20:10 -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 017C18D0002; Wed, 15 Jul 2020 03:20:09 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0046.hostedemail.com [216.40.44.46]) by kanga.kvack.org (Postfix) with ESMTP id D2B808D0005 for ; Wed, 15 Jul 2020 03:20:09 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 97AC6180AD801 for ; Wed, 15 Jul 2020 07:20:09 +0000 (UTC) X-FDA: 77039461338.25.books36_060459326ef7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id 6D70D1804E3AF for ; Wed, 15 Jul 2020 07:20:09 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,yezhenyu2@huawei.com,,RULES_HIT:30003:30034:30054:30070:30090,0,RBL:45.249.212.191:@huawei.com:.lbl8.mailshell.net-62.18.2.100 64.95.201.95;04yfx99j97oe7i8m6mp8uwxq6a3m9ypmihetofgbog8tjct8331kzg1sfcr9gtu.jswxe87kkwijh4k9kdztrndcbkrck9de771yoiogr9qat6menpzc8qzygs4646q.e-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: books36_060459326ef7 X-Filterd-Recvd-Size: 9398 Received: from huawei.com (szxga05-in.huawei.com [45.249.212.191]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Wed, 15 Jul 2020 07:20:08 +0000 (UTC) Received: from DGGEMS413-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 4FDBFEDC143ACF09E1A1; Wed, 15 Jul 2020 15:20:01 +0800 (CST) Received: from DESKTOP-KKJBAGG.china.huawei.com (10.174.186.75) by DGGEMS413-HUB.china.huawei.com (10.3.19.213) with Microsoft SMTP Server id 14.3.487.0; Wed, 15 Jul 2020 15:19:53 +0800 From: Zhenyu Ye To: , , , , , , CC: , , , , , , , , , Subject: [PATCH v3 3/3] arm64: tlb: Use the TLBI RANGE feature in arm64 Date: Wed, 15 Jul 2020 15:19:45 +0800 Message-ID: <20200715071945.897-4-yezhenyu2@huawei.com> X-Mailer: git-send-email 2.22.0.windows.1 In-Reply-To: <20200715071945.897-1-yezhenyu2@huawei.com> References: <20200715071945.897-1-yezhenyu2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.186.75] X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: 6D70D1804E3AF 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: Add __TLBI_VADDR_RANGE macro and rewrite __flush_tlb_range(). When cpu supports TLBI feature, the minimum range granularity is decided by 'scale', so we can not flush all pages by one instruction in some cases. For example, when the pages = 0xe81a, let's start 'scale' from maximum, and find right 'num' for each 'scale': 1. scale = 3, we can flush no pages because the minimum range is 2^(5*3 + 1) = 0x10000. 2. scale = 2, the minimum range is 2^(5*2 + 1) = 0x800, we can flush 0xe800 pages this time, the num = 0xe800/0x800 - 1 = 0x1c. Remaining pages is 0x1a; 3. scale = 1, the minimum range is 2^(5*1 + 1) = 0x40, no page can be flushed. 4. scale = 0, we flush the remaining 0x1a pages, the num = 0x1a/0x2 - 1 = 0xd. However, in most scenarios, the pages = 1 when flush_tlb_range() is called. Start from scale = 3 or other proper value (such as scale = ilog2(pages)), will incur extra overhead. So increase 'scale' from 0 to maximum, the flush order is exactly opposite to the example. Signed-off-by: Zhenyu Ye Link: https://lore.kernel.org/r/20200710094420.517-3-yezhenyu2@huawei.com [catalin.marinas@arm.com: removed unnecessary masks in __TLBI_VADDR_RANGE] [catalin.marinas@arm.com: __TLB_RANGE_NUM subtracts 1] [catalin.marinas@arm.com: minor adjustments to the comments] Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/tlbflush.h | 156 ++++++++++++++++++++++++------ 1 file changed, 127 insertions(+), 29 deletions(-) diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index 2cb275efcea3..4a21d8dc0312 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -60,6 +60,31 @@ __ta; \ }) +/* + * Get translation granule of the system, which is decided by + * PAGE_SIZE. Used by TTL. + * - 4KB : 1 + * - 16KB : 2 + * - 64KB : 3 + */ +#define TLBI_TTL_TG_4K 1 +#define TLBI_TTL_TG_16K 2 +#define TLBI_TTL_TG_64K 3 + +static inline unsigned long get_trans_granule(void) +{ + switch (PAGE_SIZE) { + case SZ_4K: + return TLBI_TTL_TG_4K; + case SZ_16K: + return TLBI_TTL_TG_16K; + case SZ_64K: + return TLBI_TTL_TG_64K; + default: + return 0; + } +} + /* * Level-based TLBI operations. * @@ -73,9 +98,6 @@ * in asm/stage2_pgtable.h. */ #define TLBI_TTL_MASK GENMASK_ULL(47, 44) -#define TLBI_TTL_TG_4K 1 -#define TLBI_TTL_TG_16K 2 -#define TLBI_TTL_TG_64K 3 #define __tlbi_level(op, addr, level) do { \ u64 arg = addr; \ @@ -83,19 +105,7 @@ if (cpus_have_const_cap(ARM64_HAS_ARMv8_4_TTL) && \ level) { \ u64 ttl = level & 3; \ - \ - switch (PAGE_SIZE) { \ - case SZ_4K: \ - ttl |= TLBI_TTL_TG_4K << 2; \ - break; \ - case SZ_16K: \ - ttl |= TLBI_TTL_TG_16K << 2; \ - break; \ - case SZ_64K: \ - ttl |= TLBI_TTL_TG_64K << 2; \ - break; \ - } \ - \ + ttl |= get_trans_granule() << 2; \ arg &= ~TLBI_TTL_MASK; \ arg |= FIELD_PREP(TLBI_TTL_MASK, ttl); \ } \ @@ -108,6 +118,44 @@ __tlbi_level(op, (arg | USER_ASID_FLAG), level); \ } while (0) +/* + * This macro creates a properly formatted VA operand for the TLB RANGE. + * The value bit assignments are: + * + * +----------+------+-------+-------+-------+----------------------+ + * | ASID | TG | SCALE | NUM | TTL | BADDR | + * +-----------------+-------+-------+-------+----------------------+ + * |63 48|47 46|45 44|43 39|38 37|36 0| + * + * The address range is determined by below formula: + * [BADDR, BADDR + (NUM + 1) * 2^(5*SCALE + 1) * PAGESIZE) + * + */ +#define __TLBI_VADDR_RANGE(addr, asid, scale, num, ttl) \ + ({ \ + unsigned long __ta = (addr) >> PAGE_SHIFT; \ + __ta &= GENMASK_ULL(36, 0); \ + __ta |= (unsigned long)(ttl) << 37; \ + __ta |= (unsigned long)(num) << 39; \ + __ta |= (unsigned long)(scale) << 44; \ + __ta |= get_trans_granule() << 46; \ + __ta |= (unsigned long)(asid) << 48; \ + __ta; \ + }) + +/* These macros are used by the TLBI RANGE feature. */ +#define __TLBI_RANGE_PAGES(num, scale) \ + ((unsigned long)((num) + 1) << (5 * (scale) + 1)) +#define MAX_TLBI_RANGE_PAGES __TLBI_RANGE_PAGES(31, 3) + +/* + * Generate 'num' values from -1 to 30 with -1 rejected by the + * __flush_tlb_range() loop below. + */ +#define TLBI_RANGE_MASK GENMASK_ULL(4, 0) +#define __TLBI_RANGE_NUM(pages, scale) \ + ((((pages) >> (5 * (scale) + 1)) & TLBI_RANGE_MASK) - 1) + /* * TLB Invalidation * ================ @@ -231,32 +279,82 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma, unsigned long stride, bool last_level, int tlb_level) { + int num = 0; + int scale = 0; unsigned long asid = ASID(vma->vm_mm); unsigned long addr; + unsigned long pages; start = round_down(start, stride); end = round_up(end, stride); + pages = (end - start) >> PAGE_SHIFT; - if ((end - start) >= (MAX_TLBI_OPS * stride)) { + /* + * When not uses TLB range ops, we can handle up to + * (MAX_TLBI_OPS - 1) pages; + * When uses TLB range ops, we can handle up to + * (MAX_TLBI_RANGE_PAGES - 1) pages. + */ + if ((!(cpus_have_const_cap(ARM64_HAS_TLB_RANGE) && + IS_ENABLED(CONFIG_ARM64_TLB_RANGE)) && + (end - start) >= (MAX_TLBI_OPS * stride)) || + pages >= MAX_TLBI_RANGE_PAGES) { flush_tlb_mm(vma->vm_mm); return; } - /* Convert the stride into units of 4k */ - stride >>= 12; + dsb(ishst); - start = __TLBI_VADDR(start, asid); - end = __TLBI_VADDR(end, asid); + /* + * When the CPU does not support TLB range operations, flush the TLB + * entries one by one at the granularity of 'stride'. If the the TLB + * range ops are supported, then: + * + * 1. If 'pages' is odd, flush the first page through non-range + * operations; + * + * 2. For remaining pages: the minimum range granularity is decided + * by 'scale', so multiple range TLBI operations may be required. + * Start from scale = 0, flush the corresponding number of pages + * ((num+1)*2^(5*scale+1) starting from 'addr'), then increase it + * until no pages left. + * + * Note that certain ranges can be represented by either num = 31 and + * scale or num = 0 and scale + 1. The loop below favours the latter + * since num is limited to 30 by the __TLBI_RANGE_NUM() macro. + */ + while (pages > 0) { + if (!IS_ENABLED(CONFIG_ARM64_TLB_RANGE) || + !cpus_have_const_cap(ARM64_HAS_TLB_RANGE) || + pages % 2 == 1) { + addr = __TLBI_VADDR(start, asid); + if (last_level) { + __tlbi_level(vale1is, addr, tlb_level); + __tlbi_user_level(vale1is, addr, tlb_level); + } else { + __tlbi_level(vae1is, addr, tlb_level); + __tlbi_user_level(vae1is, addr, tlb_level); + } + start += stride; + pages -= stride >> PAGE_SHIFT; + continue; + } - dsb(ishst); - for (addr = start; addr < end; addr += stride) { - if (last_level) { - __tlbi_level(vale1is, addr, tlb_level); - __tlbi_user_level(vale1is, addr, tlb_level); - } else { - __tlbi_level(vae1is, addr, tlb_level); - __tlbi_user_level(vae1is, addr, tlb_level); + num = __TLBI_RANGE_NUM(pages, scale); + if (num >= 0) { + addr = __TLBI_VADDR_RANGE(start, asid, scale, + num, tlb_level); + if (last_level) { + __tlbi(rvale1is, addr); + __tlbi_user(rvale1is, addr); + } else { + __tlbi(rvae1is, addr); + __tlbi_user(rvae1is, addr); + } + start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; + pages -= __TLBI_RANGE_PAGES(num, scale); } + scale++; } dsb(ish); }