diff options
| author | Mike Frysinger | 2009-04-23 21:28:32 +0000 |
|---|---|---|
| committer | Mike Frysinger | 2010-05-21 09:03:15 -0400 |
| commit | f074e48e0a54d8c1370f319ef95e71f796cd8048 (patch) | |
| tree | ee170cbbf14310c581a1f1b21e6215ede2a04eb1 | |
| parent | 7a9b149212f3716c598afe973b6261fd58453b7a (diff) | |
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>
| -rw-r--r-- | arch/blackfin/include/asm/pgtable.h | 3 | ||||
| -rw-r--r-- | arch/blackfin/mm/init.c | 29 |
2 files changed, 6 insertions, 26 deletions
diff --git a/arch/blackfin/include/asm/pgtable.h b/arch/blackfin/include/asm/pgtable.h index 821c699c2238..dcca3e6d6e80 100644 --- a/arch/blackfin/include/asm/pgtable.h +++ b/arch/blackfin/include/asm/pgtable.h @@ -80,7 +80,8 @@ PTE_BIT_FUNC(mkyoung, |= _PAGE_ACCESSED); * ZERO_PAGE is a global shared page that is always zero: used * 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); diff --git a/arch/blackfin/mm/init.c b/arch/blackfin/mm/init.c index 355b87aa6b93..10c8a59a96c5 100644 --- a/arch/blackfin/mm/init.c +++ b/arch/blackfin/mm/init.c @@ -15,23 +15,11 @@ #include "blackfin_sram.h" /* - * BAD_PAGE is the page that is used for page faults when linux - * is out-of-memory. Older versions of linux just did a - * 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. + * ZERO_PAGE is a special page that is used for zero-initialized data and COW. + * Let the bss do its zero-init magic so we don't have to do it ourselves. */ -static unsigned long empty_bad_page_table; - -static unsigned long empty_bad_page; - -static unsigned long empty_zero_page; +char empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); +EXPORT_SYMBOL(empty_zero_page); #ifndef CONFIG_EXCEPTION_L1_SCRATCH #if defined CONFIG_SYSCALL_TAB_L1 @@ -60,15 +48,6 @@ void __init paging_init(void) 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_fs(KERNEL_DS); |