UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

Blackfin: drop unused bad_page pages and move zero_page to the bss 

The empty_bad_page/empty_bad_page_table pages are unused, so punt them.
The zero_page is always allocated, so push it out to the bss to speed up
the booting process a bit and pack data nicer.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
This commit is contained in:
Mike Frysinger 2009-04-23 21:28:32 +00:00
parent 7a9b149212
commit f074e48e0a
2 changed files with 6 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/blackfin/include/asm/pgtable.h
View File

@ -80,7 +80,8 @@ PTE_BIT_FUNC(mkyoung, |= _PAGE_ACCESSED);
* ZERO_PAGE is a global shared page that is always zero: used * ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc.. * for zero-mapped memory areas etc..
*/ */
#define ZERO_PAGE(vaddr) (virt_to_page(0)) #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
extern char empty_zero_page[];
extern unsigned int kobjsize(const void *objp); extern unsigned int kobjsize(const void *objp);

29
arch/blackfin/mm/init.c
View File

@ -15,23 +15,11 @@
#include "blackfin_sram.h" #include "blackfin_sram.h"
/* /*
* BAD_PAGE is the page that is used for page faults when linux * ZERO_PAGE is a special page that is used for zero-initialized data and COW.
* is out-of-memory. Older versions of linux just did a * Let the bss do its zero-init magic so we don't have to do it ourselves.
* do_exit(), but using this instead means there is less risk
* for a process dying in kernel mode, possibly leaving a inode
* unused etc..
*
* BAD_PAGETABLE is the accompanying page-table: it is initialized
* to point to BAD_PAGE entries.
*
* ZERO_PAGE is a special page that is used for zero-initialized
* data and COW.
*/ */
static unsigned long empty_bad_page_table; char empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
EXPORT_SYMBOL(empty_zero_page);
static unsigned long empty_bad_page;
static unsigned long empty_zero_page;
#ifndef CONFIG_EXCEPTION_L1_SCRATCH #ifndef CONFIG_EXCEPTION_L1_SCRATCH
#if defined CONFIG_SYSCALL_TAB_L1 #if defined CONFIG_SYSCALL_TAB_L1
@ -59,15 +47,6 @@ void __init paging_init(void)
pr_debug("start_mem is %#lx virtual_end is %#lx\n", PAGE_ALIGN(memory_start), end_mem); pr_debug("start_mem is %#lx virtual_end is %#lx\n", PAGE_ALIGN(memory_start), end_mem);
/*
* initialize the bad page table and bad page to point
* to a couple of allocated pages
*/
empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
memset((void *)empty_zero_page, 0, PAGE_SIZE);
/* /*
* Set up SFC/DFC registers (user data space) * Set up SFC/DFC registers (user data space)
*/ */