[PATCH 2/3] arm64: vdso: put read only/mostly objects into proper sections
From: Jisheng Zhang <hidden>
Date: 2016-08-10 20:29:57
Also in:
lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
vdso_pages and vdso_spec are initialized by vdso_init(), thereafter are mostly read during vdso special mapping handling. vectors_page is initialized by alloc_vectors_page(), thereafter is mostly read during aarch32 vectors special mapping handling. The fact that they are mostly read and not written to makes them candidates for __read_mostly declarations. The vm_special_mapping spec is never modified, so mark it as const. This patch also removes global vdso_pagelist. Signed-off-by: Jisheng Zhang <redacted> --- arch/arm64/kernel/vdso.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-)
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index e320e8f..e62da76 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c@@ -37,8 +37,7 @@ #include <asm/vdso_datapage.h> extern char vdso_start, vdso_end; -static unsigned long vdso_pages; -static struct page **vdso_pagelist; +static unsigned long vdso_pages __read_mostly; /* * 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] __read_mostly; static int __init alloc_vectors_page(void) {
@@ -88,7 +87,7 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) { struct mm_struct *mm = current->mm; unsigned long addr = AARCH32_VECTORS_BASE; - static struct vm_special_mapping spec = { + static const struct vm_special_mapping spec = { .name = "[vectors]", .pages = vectors_page,
@@ -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] __read_mostly = { + { + .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; }
--
2.8.1