From: Hugh Dickins <hugh@veritas.com>
Remove the support for pte_chain rmap from page table initialization, just
continue to maintain nr_page_table_pages (but only for user page tables -
it also counted vmalloc page tables before, little need, and I'm unsure if
per-cpu stats are safe early enough on all arches). mm/memory.c is the
only core file affected.
But ppc and ppc64 have found the old rmap page table initialization useful
to support their ptep_test_and_clear_young: so transfer rmap's
initialization to them (even on kernel page tables? well, okay).
---
25-akpm/arch/arm/mm/mm-armv.c | 3 +--
25-akpm/arch/ppc/mm/pgtable.c | 28 +++++++++++++++++++---------
25-akpm/arch/ppc64/mm/hugetlbpage.c | 3 +--
25-akpm/arch/ppc64/mm/tlb.c | 4 ++--
25-akpm/include/asm-ppc64/pgalloc.h | 31 +++++++++++++++++++++++--------
25-akpm/mm/memory.c | 6 ++----
6 files changed, 48 insertions(+), 27 deletions(-)
diff -puN arch/arm/mm/mm-armv.c~rmap-12-pgtable-remove-rmap arch/arm/mm/mm-armv.c
--- 25/arch/arm/mm/mm-armv.c~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.953376640 -0700
+++ 25-akpm/arch/arm/mm/mm-armv.c 2004-04-27 01:30:24.963375120 -0700
@@ -18,7 +18,6 @@
#include <asm/pgalloc.h>
#include <asm/page.h>
-#include <asm/rmap.h>
#include <asm/io.h>
#include <asm/setup.h>
#include <asm/tlbflush.h>
@@ -231,7 +230,7 @@ void free_pgd_slow(pgd_t *pgd)
pte = pmd_page(*pmd);
pmd_clear(pmd);
- pgtable_remove_rmap(pte);
+ dec_page_state(nr_page_table_pages);
pte_free(pte);
pmd_free(pmd);
free:
diff -puN arch/ppc64/mm/hugetlbpage.c~rmap-12-pgtable-remove-rmap arch/ppc64/mm/hugetlbpage.c
--- 25/arch/ppc64/mm/hugetlbpage.c~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.954376488 -0700
+++ 25-akpm/arch/ppc64/mm/hugetlbpage.c 2004-04-27 01:30:24.963375120 -0700
@@ -24,7 +24,6 @@
#include <asm/machdep.h>
#include <asm/cputable.h>
#include <asm/tlb.h>
-#include <asm/rmap.h>
#include <linux/sysctl.h>
@@ -203,7 +202,7 @@ static int prepare_low_seg_for_htlb(stru
}
page = pmd_page(*pmd);
pmd_clear(pmd);
- pgtable_remove_rmap(page);
+ dec_page_state(nr_page_table_pages);
pte_free_tlb(tlb, page);
}
tlb_finish_mmu(tlb, start, end);
diff -puN arch/ppc64/mm/tlb.c~rmap-12-pgtable-remove-rmap arch/ppc64/mm/tlb.c
--- 25/arch/ppc64/mm/tlb.c~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.956376184 -0700
+++ 25-akpm/arch/ppc64/mm/tlb.c 2004-04-27 01:30:24.964374968 -0700
@@ -31,7 +31,6 @@
#include <asm/tlb.h>
#include <asm/hardirq.h>
#include <linux/highmem.h>
-#include <asm/rmap.h>
DEFINE_PER_CPU(struct ppc64_tlb_batch, ppc64_tlb_batch);
@@ -59,7 +58,8 @@ void hpte_update(pte_t *ptep, unsigned l
ptepage = virt_to_page(ptep);
mm = (struct mm_struct *) ptepage->mapping;
- addr = ptep_to_address(ptep);
+ addr = ptepage->index +
+ (((unsigned long)ptep & ~PAGE_MASK) * PTRS_PER_PTE);
if (REGION_ID(addr) == USER_REGION_ID)
context = mm->context.id;
diff -puN arch/ppc/mm/pgtable.c~rmap-12-pgtable-remove-rmap arch/ppc/mm/pgtable.c
--- 25/arch/ppc/mm/pgtable.c~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.957376032 -0700
+++ 25-akpm/arch/ppc/mm/pgtable.c 2004-04-27 01:30:24.965374816 -0700
@@ -86,9 +86,14 @@ pte_t *pte_alloc_one_kernel(struct mm_st
extern int mem_init_done;
extern void *early_get_page(void);
- if (mem_init_done)
+ if (mem_init_done) {
pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
- else
+ if (pte) {
+ struct page *ptepage = virt_to_page(pte);
+ ptepage->mapping = (void *) mm;
+ ptepage->index = address & PMD_MASK;
+ }
+ } else
pte = (pte_t *)early_get_page();
if (pte)
clear_page(pte);
@@ -97,7 +102,7 @@ pte_t *pte_alloc_one_kernel(struct mm_st
struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
- struct page *pte;
+ struct page *ptepage;
#ifdef CONFIG_HIGHPTE
int flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
@@ -105,10 +110,13 @@ struct page *pte_alloc_one(struct mm_str
int flags = GFP_KERNEL | __GFP_REPEAT;
#endif
- pte = alloc_pages(flags, 0);
- if (pte)
- clear_highpage(pte);
- return pte;
+ ptepage = alloc_pages(flags, 0);
+ if (ptepage) {
+ ptepage->mapping = (void *) mm;
+ ptepage->index = address & PMD_MASK;
+ clear_highpage(ptepage);
+ }
+ return ptepage;
}
void pte_free_kernel(pte_t *pte)
@@ -116,15 +124,17 @@ void pte_free_kernel(pte_t *pte)
#ifdef CONFIG_SMP
hash_page_sync();
#endif
+ virt_to_page(pte)->mapping = NULL;
free_page((unsigned long)pte);
}
-void pte_free(struct page *pte)
+void pte_free(struct page *ptepage)
{
#ifdef CONFIG_SMP
hash_page_sync();
#endif
- __free_page(pte);
+ ptepage->mapping = NULL;
+ __free_page(ptepage);
}
#ifndef CONFIG_44x
diff -puN include/asm-ppc64/pgalloc.h~rmap-12-pgtable-remove-rmap include/asm-ppc64/pgalloc.h
--- 25/include/asm-ppc64/pgalloc.h~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.958375880 -0700
+++ 25-akpm/include/asm-ppc64/pgalloc.h 2004-04-27 01:30:24.965374816 -0700
@@ -48,28 +48,43 @@ pmd_free(pmd_t *pmd)
pmd_populate_kernel(mm, pmd, page_address(pte_page))
static inline pte_t *
-pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
+pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
- return kmem_cache_alloc(zero_cache, GFP_KERNEL|__GFP_REPEAT);
+ pte_t *pte;
+ pte = kmem_cache_alloc(zero_cache, GFP_KERNEL|__GFP_REPEAT);
+ if (pte) {
+ struct page *ptepage = virt_to_page(pte);
+ ptepage->mapping = (void *) mm;
+ ptepage->index = address & PMD_MASK;
+ }
+ return pte;
}
static inline struct page *
pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
- pte_t *pte = pte_alloc_one_kernel(mm, address);
-
- if (pte)
- return virt_to_page(pte);
-
+ pte_t *pte;
+ pte = kmem_cache_alloc(zero_cache, GFP_KERNEL|__GFP_REPEAT);
+ if (pte) {
+ struct page *ptepage = virt_to_page(pte);
+ ptepage->mapping = (void *) mm;
+ ptepage->index = address & PMD_MASK;
+ return ptepage;
+ }
return NULL;
}
static inline void pte_free_kernel(pte_t *pte)
{
+ virt_to_page(pte)->mapping = NULL;
kmem_cache_free(zero_cache, pte);
}
-#define pte_free(pte_page) pte_free_kernel(page_address(pte_page))
+static inline void pte_free(struct page *ptepage)
+{
+ ptepage->mapping = NULL;
+ kmem_cache_free(zero_cache, page_address(ptepage));
+}
struct pte_freelist_batch
{
diff -puN mm/memory.c~rmap-12-pgtable-remove-rmap mm/memory.c
--- 25/mm/memory.c~rmap-12-pgtable-remove-rmap 2004-04-27 01:30:24.959375728 -0700
+++ 25-akpm/mm/memory.c 2004-04-27 01:30:24.966374664 -0700
@@ -48,7 +48,6 @@
#include <linux/init.h>
#include <asm/pgalloc.h>
-#include <asm/rmap.h>
#include <asm/uaccess.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
@@ -105,7 +104,7 @@ static inline void free_one_pmd(struct m
}
page = pmd_page(*dir);
pmd_clear(dir);
- pgtable_remove_rmap(page);
+ dec_page_state(nr_page_table_pages);
pte_free_tlb(tlb, page);
}
@@ -164,7 +163,7 @@ pte_t fastcall * pte_alloc_map(struct mm
pte_free(new);
goto out;
}
- pgtable_add_rmap(new, mm, address);
+ inc_page_state(nr_page_table_pages);
pmd_populate(mm, pmd, new);
}
out:
@@ -190,7 +189,6 @@ pte_t fastcall * pte_alloc_kernel(struct
pte_free_kernel(new);
goto out;
}
- pgtable_add_rmap(virt_to_page(new), mm, address);
pmd_populate_kernel(mm, pmd, new);
}
out:
_