From patchwork Wed Feb 5 15:09:54 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 13961383 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ECFF7C02192 for ; Wed, 5 Feb 2025 15:31:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QIxxSOtTOWfkgJ6ZPTh9wpPoFqmWlmW/dFwplfHXX5c=; b=FVh+3VQyaSbVyB401SzwBJZjki 0pCbQoRZaSwhxL4PVV7/qbtT8eb0R/tQ1StdeskvBKxRf9cwCO/5B2WdigL6dEz4V9rPEfwPU+A88 dN/Dv36kLNac2XqSVBHRr2CwlHsjkARbTQkJ5JJg5x9fAdmxE+4vo0yZCgpoMIhW0NWJnXjTyBrbM PXG16INzDjgpIxnP4PRg994dVq/eE/wk31DJ0DKh4vftKANOdLl3iKPKlOafgIUOdHaK1+pR08bzm DXlbm9QBeqZV62ZBwYJ7IyhUitdqXMDXmIIm/B+DTKaPqAxeJ7S73iWBeA6HtU680NBfUv4EO/0wx hIr+QJNA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tfhN1-00000003mBp-3bTg; Wed, 05 Feb 2025 15:31:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tfh3S-00000003iNi-4BAX for linux-arm-kernel@lists.infradead.org; Wed, 05 Feb 2025 15:11:08 +0000 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 439D7165C; Wed, 5 Feb 2025 07:11:30 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 27B823F5A1; Wed, 5 Feb 2025 07:11:04 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Muchun Song , Pasha Tatashin , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Mark Rutland , Ard Biesheuvel , Anshuman Khandual , Dev Jain , Alexandre Ghiti , Steve Capper , Kevin Brodsky Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v1 14/16] mm/vmalloc: Batch arch_sync_kernel_mappings() more efficiently Date: Wed, 5 Feb 2025 15:09:54 +0000 Message-ID: <20250205151003.88959-15-ryan.roberts@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250205151003.88959-1-ryan.roberts@arm.com> References: <20250205151003.88959-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250205_071107_126309_28DEC353 X-CRM114-Status: GOOD ( 15.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When page_shift is greater than PAGE_SIZE, __vmap_pages_range_noflush() will call vmap_range_noflush() for each individual huge page. But vmap_range_noflush() would previously call arch_sync_kernel_mappings() directly so this would end up being called for every huge page. We can do better than this; refactor the call into the outer __vmap_pages_range_noflush() so that it is only called once for the entire batch operation. This will benefit performance for arm64 which is about to opt-in to using the hook. Signed-off-by: Ryan Roberts --- mm/vmalloc.c | 60 ++++++++++++++++++++++++++-------------------------- 1 file changed, 30 insertions(+), 30 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 68950b1824d0..50fd44439875 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -285,40 +285,38 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, static int vmap_range_noflush(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, - unsigned int max_page_shift) + unsigned int max_page_shift, pgtbl_mod_mask *mask) { pgd_t *pgd; - unsigned long start; unsigned long next; int err; - pgtbl_mod_mask mask = 0; might_sleep(); BUG_ON(addr >= end); - start = addr; pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, - max_page_shift, &mask); + max_page_shift, mask); if (err) break; } while (pgd++, phys_addr += (next - addr), addr = next, addr != end); - if (mask & ARCH_PAGE_TABLE_SYNC_MASK) - arch_sync_kernel_mappings(start, end); - return err; } int vmap_page_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { + pgtbl_mod_mask mask = 0; int err; err = vmap_range_noflush(addr, end, phys_addr, pgprot_nx(prot), - ioremap_max_page_shift); + ioremap_max_page_shift, &mask); + if (mask & ARCH_PAGE_TABLE_SYNC_MASK) + arch_sync_kernel_mappings(addr, end); + flush_cache_vmap(addr, end); if (!err) err = kmsan_ioremap_page_range(addr, end, phys_addr, prot, @@ -587,29 +585,24 @@ static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr, } static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, - pgprot_t prot, struct page **pages) + pgprot_t prot, struct page **pages, pgtbl_mod_mask *mask) { - unsigned long start = addr; pgd_t *pgd; unsigned long next; int err = 0; int nr = 0; - pgtbl_mod_mask mask = 0; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); if (pgd_bad(*pgd)) - mask |= PGTBL_PGD_MODIFIED; - err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask); + *mask |= PGTBL_PGD_MODIFIED; + err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, mask); if (err) break; } while (pgd++, addr = next, addr != end); - if (mask & ARCH_PAGE_TABLE_SYNC_MASK) - arch_sync_kernel_mappings(start, end); - return err; } @@ -626,26 +619,33 @@ int __vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift) { unsigned int i, nr = (end - addr) >> PAGE_SHIFT; + unsigned long start = addr; + pgtbl_mod_mask mask = 0; + int err = 0; WARN_ON(page_shift < PAGE_SHIFT); if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) || - page_shift == PAGE_SHIFT) - return vmap_small_pages_range_noflush(addr, end, prot, pages); - - for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) { - int err; - - err = vmap_range_noflush(addr, addr + (1UL << page_shift), - page_to_phys(pages[i]), prot, - page_shift); - if (err) - return err; + page_shift == PAGE_SHIFT) { + err = vmap_small_pages_range_noflush(addr, end, prot, pages, + &mask); + } else { + for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) { + err = vmap_range_noflush(addr, + addr + (1UL << page_shift), + page_to_phys(pages[i]), prot, + page_shift, &mask); + if (err) + break; - addr += 1UL << page_shift; + addr += 1UL << page_shift; + } } - return 0; + if (mask & ARCH_PAGE_TABLE_SYNC_MASK) + arch_sync_kernel_mappings(start, end); + + return err; } int vmap_pages_range_noflush(unsigned long addr, unsigned long end,