From patchwork Thu Aug 11 13:36:49 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jisheng Zhang X-Patchwork-Id: 9275313 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1F6766022E for ; Thu, 11 Aug 2016 13:43:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E4CF28672 for ; Thu, 11 Aug 2016 13:43:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 029022867A; Thu, 11 Aug 2016 13:43:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 8918128672 for ; Thu, 11 Aug 2016 13:43:52 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bXqFk-00086W-KN; Thu, 11 Aug 2016 13:42:32 +0000 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bXqEq-0007lh-45 for linux-arm-kernel@lists.infradead.org; Thu, 11 Aug 2016 13:41:38 +0000 Received: from pps.filterd (m0045851.ppops.net [127.0.0.1]) by mx0b-0016f401.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u7BDeerj014666; Thu, 11 Aug 2016 06:41:08 -0700 Received: from sc-exch04.marvell.com ([199.233.58.184]) by mx0b-0016f401.pphosted.com with ESMTP id 24nfdkqnpx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Thu, 11 Aug 2016 06:41:08 -0700 Received: from SC-EXCH03.marvell.com (10.93.176.83) by SC-EXCH04.marvell.com (10.93.176.84) with Microsoft SMTP Server (TLS) id 15.0.1104.5; Thu, 11 Aug 2016 06:41:06 -0700 Received: from maili.marvell.com (10.93.176.43) by SC-EXCH03.marvell.com (10.93.176.83) with Microsoft SMTP Server id 15.0.1104.5 via Frontend Transport; Thu, 11 Aug 2016 06:41:06 -0700 Received: from xhacker.marvell.com (unknown [10.37.130.202]) by maili.marvell.com (Postfix) with ESMTP id CC1AF3F703F; Thu, 11 Aug 2016 06:41:04 -0700 (PDT) From: Jisheng Zhang To: , , , Subject: [PATCH v2 4/4] arm64: apply __ro_after_init to some objects Date: Thu, 11 Aug 2016 21:36:49 +0800 Message-ID: <1470922609-754-5-git-send-email-jszhang@marvell.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1470922609-754-1-git-send-email-jszhang@marvell.com> References: <1470922609-754-1-git-send-email-jszhang@marvell.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-08-11_10:, , signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1608110183 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160811_064136_477120_D3B46938 X-CRM114-Status: GOOD ( 14.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jisheng Zhang , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP These objects are set during initialization, thereafter are read only. Previously I only want to mark vdso_pages, vdso_spec, vectors_page and cpu_ops as __read_mostly from performance point of view. Then inspired by Kees's patch[1] to apply more __ro_after_init for arm, I think it's better to mark them as __ro_after_init. What's more, I find some more objects are also read only after init. So apply __ro_after_init to all of them. This patch also removes global vdso_pagelist and tries to clean up vdso_spec[] assignment code. [1] http://www.spinics.net/lists/arm-kernel/msg523188.html Signed-off-by: Jisheng Zhang --- arch/arm64/kernel/cpu_ops.c | 2 +- arch/arm64/kernel/kaslr.c | 2 +- arch/arm64/kernel/vdso.c | 27 +++++++++++++-------------- arch/arm64/mm/dma-mapping.c | 2 +- arch/arm64/mm/init.c | 4 ++-- arch/arm64/mm/mmu.c | 2 +- 6 files changed, 19 insertions(+), 20 deletions(-) diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c index c7cfb8f..6d32d1a 100644 --- a/arch/arm64/kernel/cpu_ops.c +++ b/arch/arm64/kernel/cpu_ops.c @@ -28,7 +28,7 @@ extern const struct cpu_operations smp_spin_table_ops; extern const struct cpu_operations acpi_parking_protocol_ops; extern const struct cpu_operations cpu_psci_ops; -const struct cpu_operations *cpu_ops[NR_CPUS]; +const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; static const struct cpu_operations *dt_supported_cpu_ops[] __initconst = { &smp_spin_table_ops, diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c index 8ebabc4..93c47e1 100644 --- a/arch/arm64/kernel/kaslr.c +++ b/arch/arm64/kernel/kaslr.c @@ -20,7 +20,7 @@ #include #include -u64 module_alloc_base __read_mostly; +u64 module_alloc_base __ro_after_init; u16 memstart_offset_seed __initdata; static __init u64 get_kaslr_seed(void *fdt) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 10ad8ab..0af41de 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -37,8 +37,7 @@ #include extern char vdso_start, vdso_end; -static unsigned long vdso_pages; -static struct page **vdso_pagelist; +static unsigned long vdso_pages __ro_after_init; /* * The vDSO data page. @@ -53,7 +52,7 @@ struct vdso_data *vdso_data = &vdso_data_store.data; /* * Create and map the vectors page for AArch32 tasks. */ -static struct page *vectors_page[1]; +static struct page *vectors_page[1] __ro_after_init; static int __init alloc_vectors_page(void) { @@ -110,11 +109,19 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) } #endif /* CONFIG_COMPAT */ -static struct vm_special_mapping vdso_spec[2]; +static struct vm_special_mapping vdso_spec[2] __ro_after_init = { + { + .name = "[vvar]", + }, + { + .name = "[vdso]", + }, +}; static int __init vdso_init(void) { int i; + struct page **vdso_pagelist; if (memcmp(&vdso_start, "\177ELF", 4)) { pr_err("vDSO is not a valid ELF object!\n"); @@ -138,16 +145,8 @@ static int __init vdso_init(void) for (i = 0; i < vdso_pages; i++) vdso_pagelist[i + 1] = pfn_to_page(PHYS_PFN(__pa(&vdso_start)) + i); - /* Populate the special mapping structures */ - vdso_spec[0] = (struct vm_special_mapping) { - .name = "[vvar]", - .pages = vdso_pagelist, - }; - - vdso_spec[1] = (struct vm_special_mapping) { - .name = "[vdso]", - .pages = &vdso_pagelist[1], - }; + vdso_spec[0].pages = vdso_pagelist; + vdso_spec[1].pages = &vdso_pagelist[1]; return 0; } diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index c4284c4..59d44e7 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -30,7 +30,7 @@ #include -static int swiotlb __read_mostly; +static int swiotlb __ro_after_init; static pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot, bool coherent) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index bbb7ee7..e8b81ea 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -55,8 +55,8 @@ * executes, which assigns it its actual value. So use a default value * that cannot be mistaken for a real physical address. */ -s64 memstart_addr __read_mostly = -1; -phys_addr_t arm64_dma_phys_limit __read_mostly; +s64 memstart_addr __ro_after_init = -1; +phys_addr_t arm64_dma_phys_limit __ro_after_init; #ifdef CONFIG_BLK_DEV_INITRD static int __init early_initrd(char *p) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 4989948..6029bed 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -46,7 +46,7 @@ u64 idmap_t0sz = TCR_T0SZ(VA_BITS); -u64 kimage_voffset __read_mostly; +u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); /*