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| author | Andy Lutomirski <luto@mit.edu> | 2011-07-21 15:47:10 -0400 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2011-07-21 13:41:53 -0700 |
| commit | aafade242ff24fac3aabf61c7861dfa44a3c2445 (patch) | |
| tree | e28352a5883b5684466ea44f3caebe99c088eaf7 | |
| parent | ae7bd11b471931752e5609094ca0a49386590524 (diff) | |
| download | linux-next-aafade242ff24fac3aabf61c7861dfa44a3c2445.tar.gz | |
x86-64, vdso: Do not allocate memory for the vDSO
We can map the vDSO straight from kernel data, saving a few page
allocations. As an added bonus, the deleted code contained a memory
leak.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/2c4ed5c2c2e93603790229e0c3403ae506ccc0cb.1311277573.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| -rw-r--r-- | arch/x86/vdso/vdso.S | 15 | ||||
| -rw-r--r-- | arch/x86/vdso/vma.c | 25 |
2 files changed, 19 insertions, 21 deletions
diff --git a/arch/x86/vdso/vdso.S b/arch/x86/vdso/vdso.S index 1d3aa6b87181..1b979c12ba85 100644 --- a/arch/x86/vdso/vdso.S +++ b/arch/x86/vdso/vdso.S @@ -1,10 +1,21 @@ +#include <asm/page_types.h> +#include <linux/linkage.h> #include <linux/init.h> -__INITDATA +__PAGE_ALIGNED_DATA .globl vdso_start, vdso_end + .align PAGE_SIZE vdso_start: .incbin "arch/x86/vdso/vdso.so" vdso_end: -__FINIT +.previous + + .globl vdso_pages + .bss + .align 8 + .type vdso_pages, @object +vdso_pages: + .zero (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE * 8 + .size vdso_pages, .-vdso_pages diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index c39938d1332f..316fbca3490e 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -14,13 +14,14 @@ #include <asm/vgtod.h> #include <asm/proto.h> #include <asm/vdso.h> +#include <asm/page.h> unsigned int __read_mostly vdso_enabled = 1; extern char vdso_start[], vdso_end[]; extern unsigned short vdso_sync_cpuid; -static struct page **vdso_pages; +extern struct page *vdso_pages[]; static unsigned vdso_size; static void __init patch_vdso(void *vdso, size_t len) @@ -54,7 +55,7 @@ found: apply_alternatives(alt_data, alt_data + alt_sec->sh_size); } -static int __init init_vdso_vars(void) +static int __init init_vdso(void) { int npages = (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE; int i; @@ -62,26 +63,12 @@ static int __init init_vdso_vars(void) patch_vdso(vdso_start, vdso_end - vdso_start); vdso_size = npages << PAGE_SHIFT; - vdso_pages = kmalloc(sizeof(struct page *) * npages, GFP_KERNEL); - if (!vdso_pages) - goto oom; - for (i = 0; i < npages; i++) { - struct page *p; - p = alloc_page(GFP_KERNEL); - if (!p) - goto oom; - vdso_pages[i] = p; - copy_page(page_address(p), vdso_start + i*PAGE_SIZE); - } + for (i = 0; i < npages; i++) + vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE); return 0; - - oom: - printk("Cannot allocate vdso\n"); - vdso_enabled = 0; - return -ENOMEM; } -subsys_initcall(init_vdso_vars); +subsys_initcall(init_vdso); struct linux_binprm; |