linux/arch/ia64/mm/hugetlbpage.c
Mel Gorman d9c2340052 Do not depend on MAX_ORDER when grouping pages by mobility
Currently mobility grouping works at the MAX_ORDER_NR_PAGES level.  This makes
sense for the majority of users where this is also the huge page size.
However, on platforms like ia64 where the huge page size is runtime
configurable it is desirable to group at a lower order.  On x86_64 and
occasionally on x86, the hugepage size may not always be MAX_ORDER_NR_PAGES.

This patch groups pages together based on the value of HUGETLB_PAGE_ORDER.  It
uses a compile-time constant if possible and a variable where the huge page
size is runtime configurable.

It is assumed that grouping should be done at the lowest sensible order and
that the user would not want to override this.  If this is not true,
page_block order could be forced to a variable initialised via a boot-time
kernel parameter.

One potential issue with this patch is that IA64 now parses hugepagesz with
early_param() instead of __setup().  __setup() is called after the memory
allocator has been initialised and the pageblock bitmaps already setup.  In
tests on one IA64 there did not seem to be any problem with using
early_param() and in fact may be more correct as it guarantees the parameter
is handled before the parsing of hugepages=.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:00 -07:00

199 lines
4.7 KiB
C

/*
* IA-64 Huge TLB Page Support for Kernel.
*
* Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com>
* Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com>
*
* Sep, 2003: add numa support
* Feb, 2004: dynamic hugetlb page size via boot parameter
*/
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/log2.h>
#include <asm/mman.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT;
pte_t *
huge_pte_alloc (struct mm_struct *mm, unsigned long addr)
{
unsigned long taddr = htlbpage_to_page(addr);
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte = NULL;
pgd = pgd_offset(mm, taddr);
pud = pud_alloc(mm, pgd, taddr);
if (pud) {
pmd = pmd_alloc(mm, pud, taddr);
if (pmd)
pte = pte_alloc_map(mm, pmd, taddr);
}
return pte;
}
pte_t *
huge_pte_offset (struct mm_struct *mm, unsigned long addr)
{
unsigned long taddr = htlbpage_to_page(addr);
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte = NULL;
pgd = pgd_offset(mm, taddr);
if (pgd_present(*pgd)) {
pud = pud_offset(pgd, taddr);
if (pud_present(*pud)) {
pmd = pmd_offset(pud, taddr);
if (pmd_present(*pmd))
pte = pte_offset_map(pmd, taddr);
}
}
return pte;
}
int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
{
return 0;
}
#define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; }
/*
* Don't actually need to do any preparation, but need to make sure
* the address is in the right region.
*/
int prepare_hugepage_range(unsigned long addr, unsigned long len)
{
if (len & ~HPAGE_MASK)
return -EINVAL;
if (addr & ~HPAGE_MASK)
return -EINVAL;
if (REGION_NUMBER(addr) != RGN_HPAGE)
return -EINVAL;
return 0;
}
struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write)
{
struct page *page;
pte_t *ptep;
if (REGION_NUMBER(addr) != RGN_HPAGE)
return ERR_PTR(-EINVAL);
ptep = huge_pte_offset(mm, addr);
if (!ptep || pte_none(*ptep))
return NULL;
page = pte_page(*ptep);
page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT);
return page;
}
int pmd_huge(pmd_t pmd)
{
return 0;
}
struct page *
follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write)
{
return NULL;
}
void hugetlb_free_pgd_range(struct mmu_gather **tlb,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
/*
* This is called to free hugetlb page tables.
*
* The offset of these addresses from the base of the hugetlb
* region must be scaled down by HPAGE_SIZE/PAGE_SIZE so that
* the standard free_pgd_range will free the right page tables.
*
* If floor and ceiling are also in the hugetlb region, they
* must likewise be scaled down; but if outside, left unchanged.
*/
addr = htlbpage_to_page(addr);
end = htlbpage_to_page(end);
if (REGION_NUMBER(floor) == RGN_HPAGE)
floor = htlbpage_to_page(floor);
if (REGION_NUMBER(ceiling) == RGN_HPAGE)
ceiling = htlbpage_to_page(ceiling);
free_pgd_range(tlb, addr, end, floor, ceiling);
}
unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags)
{
struct vm_area_struct *vmm;
if (len > RGN_MAP_LIMIT)
return -ENOMEM;
if (len & ~HPAGE_MASK)
return -EINVAL;
/* Handle MAP_FIXED */
if (flags & MAP_FIXED) {
if (prepare_hugepage_range(addr, len))
return -EINVAL;
return addr;
}
/* This code assumes that RGN_HPAGE != 0. */
if ((REGION_NUMBER(addr) != RGN_HPAGE) || (addr & (HPAGE_SIZE - 1)))
addr = HPAGE_REGION_BASE;
else
addr = ALIGN(addr, HPAGE_SIZE);
for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
/* At this point: (!vmm || addr < vmm->vm_end). */
if (REGION_OFFSET(addr) + len > RGN_MAP_LIMIT)
return -ENOMEM;
if (!vmm || (addr + len) <= vmm->vm_start)
return addr;
addr = ALIGN(vmm->vm_end, HPAGE_SIZE);
}
}
static int __init hugetlb_setup_sz(char *str)
{
u64 tr_pages;
unsigned long long size;
if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0)
/*
* shouldn't happen, but just in case.
*/
tr_pages = 0x15557000UL;
size = memparse(str, &str);
if (*str || !is_power_of_2(size) || !(tr_pages & size) ||
size <= PAGE_SIZE ||
size >= (1UL << PAGE_SHIFT << MAX_ORDER)) {
printk(KERN_WARNING "Invalid huge page size specified\n");
return 1;
}
hpage_shift = __ffs(size);
/*
* boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT
* override here with new page shift.
*/
ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2);
return 0;
}
early_param("hugepagesz", hugetlb_setup_sz);