[PATCH] ARM: VDSO: put read only/mostly objects into proper sections

From: Jisheng Zhang
Date: Wed Aug 10 2016 - 16:24:26 EST


vdso_data_mapping is never modified, so mark it as const.

vdso_data_page and vdso_text_mapping are initialized by vdso_init(),
thereafter are mostly read during vdso special mapping handling.

The fact that they are mostly read and not written to makes them
candidates for __read_mostly declarations.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
arch/arm/kernel/vdso.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
index 994e971..c946092 100644
--- a/arch/arm/kernel/vdso.c
+++ b/arch/arm/kernel/vdso.c
@@ -47,13 +47,13 @@ unsigned int vdso_total_pages __read_mostly;
static union vdso_data_store vdso_data_store __page_aligned_data;
static struct vdso_data *vdso_data = &vdso_data_store.data;

-static struct page *vdso_data_page;
-static struct vm_special_mapping vdso_data_mapping = {
+static struct page *vdso_data_page __read_mostly;
+static const struct vm_special_mapping vdso_data_mapping = {
.name = "[vvar]",
.pages = &vdso_data_page,
};

-static struct vm_special_mapping vdso_text_mapping = {
+static struct vm_special_mapping vdso_text_mapping __read_mostly = {
.name = "[vdso]",
};

--
2.8.1