lkml.org 
[lkml]   [2008]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] x86: not overmap than end in init_memory_mapping - 64bit
Date

handle head and tail that can not aligned to big pages.

with this patch, on system that support gbpages
change
last_map_addr: 1080000000 end: 1078000000
to
last_map_addr: 1078000000 end: 1078000000

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>

---
arch/x86/mm/init_64.c | 77 ++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 65 insertions(+), 12 deletions(-)

Index: linux-2.6/arch/x86/mm/init_64.c
===================================================================
--- linux-2.6.orig/arch/x86/mm/init_64.c
+++ linux-2.6/arch/x86/mm/init_64.c
@@ -422,18 +422,25 @@ phys_pud_update(pgd_t *pgd, unsigned lon

static void __init find_early_table_space(unsigned long end)
{
- unsigned long puds, tables, start;
+ unsigned long puds, pmds, ptes, tables, start;

puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
- if (!direct_gbpages) {
- unsigned long pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
- tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
- }
- if (!cpu_has_pse) {
- unsigned long ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
- tables += round_up(ptes * sizeof(pte_t), PAGE_SIZE);
- }
+ if (direct_gbpages) {
+ unsigned long extra;
+ extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
+ pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
+ } else
+ pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
+ tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
+
+ if (cpu_has_pse) {
+ unsigned long extra;
+ extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
+ ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ } else
+ ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ tables += round_up(ptes * sizeof(pte_t), PAGE_SIZE);

/*
* RED-PEN putting page tables only on node 0 could
@@ -634,8 +641,9 @@ static unsigned long __init kernel_physi
unsigned long __init_refok init_memory_mapping(unsigned long start,
unsigned long end)
{
- unsigned long last_map_addr;
+ unsigned long last_map_addr = end;
unsigned long page_size_mask = 0;
+ unsigned long start_pfn, end_pfn;

printk(KERN_INFO "init_memory_mapping\n");

@@ -656,8 +664,53 @@ unsigned long __init_refok init_memory_m
if (cpu_has_pse)
page_size_mask |= 1 << PG_LEVEL_2M;

- last_map_addr = kernel_physical_mapping_init(start, end,
- page_size_mask);
+ /* head if not big page aligment ?*/
+ start_pfn = start >> PAGE_SHIFT;
+ end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn)
+ last_map_addr = kernel_physical_mapping_init(
+ start_pfn<<PAGE_SHIFT,
+ end_pfn<<PAGE_SHIFT, 0);
+
+ /* big page (2M) range*/
+ start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+ end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
+ << (PUD_SHIFT - PAGE_SHIFT);
+ if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
+ end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
+ if (start_pfn < end_pfn)
+ last_map_addr = kernel_physical_mapping_init(
+ start_pfn<<PAGE_SHIFT,
+ end_pfn<<PAGE_SHIFT,
+ page_size_mask & (1<<PG_LEVEL_2M));
+
+ /* big page (1G) range */
+ start_pfn = end_pfn;
+ end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn)
+ last_map_addr = kernel_physical_mapping_init(
+ start_pfn<<PAGE_SHIFT,
+ end_pfn<<PAGE_SHIFT,
+ page_size_mask & ((1<<PG_LEVEL_2M)
+ | (1<<PG_LEVEL_1G)));
+
+ /* tail is not big page (1G) alignment */
+ start_pfn = end_pfn;
+ end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn)
+ last_map_addr = kernel_physical_mapping_init(
+ start_pfn<<PAGE_SHIFT,
+ end_pfn<<PAGE_SHIFT,
+ page_size_mask & (1<<PG_LEVEL_2M));
+ /* tail is not big page (2M) alignment */
+ start_pfn = end_pfn;
+ end_pfn = end>>PAGE_SHIFT;
+ if (start_pfn < end_pfn)
+ last_map_addr = kernel_physical_mapping_init(
+ start_pfn<<PAGE_SHIFT,
+ end_pfn<<PAGE_SHIFT, 0);

if (!after_bootmem)
mmu_cr4_features = read_cr4();

\
 
 \ /
  Last update: 2008-07-08 10:47    [W:0.176 / U:38.128 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site