[PATCH] rmap 19 arch prio_tree

From: Hugh Dickins
Date: Tue Apr 27 2004 - 19:17:29 EST

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The previous patches of this prio_tree batch have been to generic only.
Now the arm and parisc __flush_dcache_page are converted to using
vma_prio_tree_next, and benefit from its selection of relevant vmas.
They're still accessing the tree without i_shared_lock or any other,
that's not forgotten but still under investigation. Include pagemap.h
for the definition of PAGE_CACHE_SHIFT. s390 and x86_64 no longer
initialize vma's shared field (whose type has changed), done later.

arch/arm/mm/fault-armv.c | 59 ++++++++++++----------------------------
arch/parisc/kernel/cache.c | 49 ++++++++++++---------------------
arch/parisc/kernel/sys_parisc.c | 14 +--------
arch/s390/kernel/compat_exec.c | 1
arch/x86_64/ia32/ia32_binfmt.c | 1
5 files changed, 39 insertions(+), 85 deletions(-)

--- 2.6.6-rc2-mm2/arch/arm/mm/fault-armv.c 2004-04-21 06:28:40.000000000 +0100
+++ rmap19/arch/arm/mm/fault-armv.c 2004-04-27 19:19:17.337481856 +0100
@@ -16,6 +16,7 @@
#include <linux/bitops.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
+#include <linux/pagemap.h>

#include <asm/cacheflush.h>
#include <asm/io.h>
@@ -187,7 +188,10 @@ void __flush_dcache_page(struct page *pa
{
struct address_space *mapping = page_mapping(page);
struct mm_struct *mm = current->active_mm;
- struct list_head *l;
+ struct vm_area_struct *mpnt = NULL;
+ struct prio_tree_iter iter;
+ unsigned long offset;
+ pgoff_t pgoff;

__cpuc_flush_dcache_page(page_address(page));

@@ -198,26 +202,16 @@ void __flush_dcache_page(struct page *pa
* With a VIVT cache, we need to also write back
* and invalidate any user data.
*/
- list_for_each(l, &mapping->i_mmap_shared) {
- struct vm_area_struct *mpnt;
- unsigned long off;
-
- mpnt = list_entry(l, struct vm_area_struct, shared);
-
+ pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+ while ((mpnt = vma_prio_tree_next(mpnt, &mapping->i_mmap_shared,
+ &iter, pgoff, pgoff)) != NULL) {
/*
* If this VMA is not in our MM, we can ignore it.
*/
if (mpnt->vm_mm != mm)
continue;
-
- if (page->index < mpnt->vm_pgoff)
- continue;
-
- off = page->index - mpnt->vm_pgoff;
- if (off >= (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT)
- continue;
-
- flush_cache_page(mpnt, mpnt->vm_start + (off << PAGE_SHIFT));
+ offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+ flush_cache_page(mpnt, mpnt->vm_start + offset);
}
}

@@ -225,9 +219,11 @@ static void
make_coherent(struct vm_area_struct *vma, unsigned long addr, struct page *page, int dirty)
{
struct address_space *mapping = page_mapping(page);
- struct list_head *l;
struct mm_struct *mm = vma->vm_mm;
- unsigned long pgoff;
+ struct vm_area_struct *mpnt = NULL;
+ struct prio_tree_iter iter;
+ unsigned long offset;
+ pgoff_t pgoff;
int aliases = 0;

if (!mapping)
@@ -240,12 +236,8 @@ make_coherent(struct vm_area_struct *vma
* space, then we need to handle them specially to maintain
* cache coherency.
*/
- list_for_each(l, &mapping->i_mmap_shared) {
- struct vm_area_struct *mpnt;
- unsigned long off;
-
- mpnt = list_entry(l, struct vm_area_struct, shared);
-
+ while ((mpnt = vma_prio_tree_next(mpnt, &mapping->i_mmap_shared,
+ &iter, pgoff, pgoff)) != NULL) {
/*
* If this VMA is not in our MM, we can ignore it.
* Note that we intentionally mask out the VMA
@@ -253,23 +245,8 @@ make_coherent(struct vm_area_struct *vma
*/
if (mpnt->vm_mm != mm || mpnt == vma)
continue;
-
- /*
- * If the page isn't in this VMA, we can also ignore it.
- */
- if (pgoff < mpnt->vm_pgoff)
- continue;
-
- off = pgoff - mpnt->vm_pgoff;
- if (off >= (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT)
- continue;
-
- off = mpnt->vm_start + (off << PAGE_SHIFT);
-
- /*
- * Ok, it is within mpnt. Fix it up.
- */
- aliases += adjust_pte(mpnt, off);
+ offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+ aliases += adjust_pte(mpnt, mpnt->vm_start + offset);
}
if (aliases)
adjust_pte(vma, addr);
--- 2.6.6-rc2-mm2/arch/parisc/kernel/cache.c 2004-04-21 06:28:44.000000000 +0100
+++ rmap19/arch/parisc/kernel/cache.c 2004-04-27 19:19:17.338481704 +0100
@@ -17,6 +17,7 @@
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/seq_file.h>
+#include <linux/pagemap.h>

#include <asm/pdc.h>
#include <asm/cache.h>
@@ -231,34 +232,30 @@ void __flush_dcache_page(struct page *pa
{
struct address_space *mapping = page_mapping(page);
struct mm_struct *mm = current->active_mm;
- struct list_head *l;
+ struct vm_area_struct *mpnt = NULL;
+ struct prio_tree_iter iter;
+ unsigned long offset;
+ pgoff_t pgoff;

flush_kernel_dcache_page(page_address(page));

if (!mapping)
return;
- /* check shared list first if it's not empty...it's usually
- * the shortest */
- list_for_each(l, &mapping->i_mmap_shared) {
- struct vm_area_struct *mpnt;
- unsigned long off;

- mpnt = list_entry(l, struct vm_area_struct, shared);
+ pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);

+ /* check shared list first if it's not empty...it's usually
+ * the shortest */
+ while ((mpnt = vma_prio_tree_next(mpnt, &mapping->i_mmap_shared,
+ &iter, pgoff, pgoff)) != NULL) {
/*
* If this VMA is not in our MM, we can ignore it.
*/
if (mpnt->vm_mm != mm)
continue;

- if (page->index < mpnt->vm_pgoff)
- continue;
-
- off = page->index - mpnt->vm_pgoff;
- if (off >= (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT)
- continue;
-
- flush_cache_page(mpnt, mpnt->vm_start + (off << PAGE_SHIFT));
+ offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+ flush_cache_page(mpnt, mpnt->vm_start + offset);

/* All user shared mappings should be equivalently mapped,
* so once we've flushed one we should be ok
@@ -268,24 +265,16 @@ void __flush_dcache_page(struct page *pa

/* then check private mapping list for read only shared mappings
* which are flagged by VM_MAYSHARE */
- list_for_each(l, &mapping->i_mmap) {
- struct vm_area_struct *mpnt;
- unsigned long off;
-
- mpnt = list_entry(l, struct vm_area_struct, shared);
-
-
+ while ((mpnt = vma_prio_tree_next(mpnt, &mapping->i_mmap,
+ &iter, pgoff, pgoff)) != NULL) {
+ /*
+ * If this VMA is not in our MM, we can ignore it.
+ */
if (mpnt->vm_mm != mm || !(mpnt->vm_flags & VM_MAYSHARE))
continue;

- if (page->index < mpnt->vm_pgoff)
- continue;
-
- off = page->index - mpnt->vm_pgoff;
- if (off >= (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT)
- continue;
-
- flush_cache_page(mpnt, mpnt->vm_start + (off << PAGE_SHIFT));
+ offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+ flush_cache_page(mpnt, mpnt->vm_start + offset);

/* All user shared mappings should be equivalently mapped,
* so once we've flushed one we should be ok
--- 2.6.6-rc2-mm2/arch/parisc/kernel/sys_parisc.c 2004-04-04 03:38:55.000000000 +0100
+++ rmap19/arch/parisc/kernel/sys_parisc.c 2004-04-27 19:19:17.339481552 +0100
@@ -68,17 +68,8 @@ static unsigned long get_unshared_area(u
* existing mapping and use the same offset. New scheme is to use the
* address of the kernel data structure as the seed for the offset.
* We'll see how that works...
- */
-#if 0
-static int get_offset(struct address_space *mapping)
-{
- struct vm_area_struct *vma = list_entry(mapping->i_mmap_shared.next,
- struct vm_area_struct, shared);
- return (vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT)) &
- (SHMLBA - 1);
-}
-#else
-/* The mapping is cacheline aligned, so there's no information in the bottom
+ *
+ * The mapping is cacheline aligned, so there's no information in the bottom
* few bits of the address. We're looking for 10 bits (4MB / 4k), so let's
* drop the bottom 8 bits and use bits 8-17.
*/
@@ -87,7 +78,6 @@ static int get_offset(struct address_spa
int offset = (unsigned long) mapping << (PAGE_SHIFT - 8);
return offset & 0x3FF000;
}
-#endif

static unsigned long get_shared_area(struct address_space *mapping,
unsigned long addr, unsigned long len, unsigned long pgoff)
--- 2.6.6-rc2-mm2/arch/s390/kernel/compat_exec.c 2004-04-26 12:39:39.560193296 +0100
+++ rmap19/arch/s390/kernel/compat_exec.c 2004-04-27 19:19:17.340481400 +0100
@@ -73,7 +73,6 @@ int setup_arg_pages32(struct linux_binpr
mpnt->vm_pgoff = 0;
mpnt->vm_file = NULL;
mpol_set_vma_default(mpnt);
- INIT_LIST_HEAD(&mpnt->shared);
mpnt->vm_private_data = (void *) 0;
insert_vm_struct(mm, mpnt);
mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
--- 2.6.6-rc2-mm2/arch/x86_64/ia32/ia32_binfmt.c 2004-04-26 12:39:40.006125504 +0100
+++ rmap19/arch/x86_64/ia32/ia32_binfmt.c 2004-04-27 19:19:17.341481248 +0100
@@ -366,7 +366,6 @@ int setup_arg_pages(struct linux_binprm
mpnt->vm_pgoff = 0;
mpnt->vm_file = NULL;
mpol_set_vma_default(mpnt);
- INIT_LIST_HEAD(&mpnt->shared);
mpnt->vm_private_data = (void *) 0;
insert_vm_struct(mm, mpnt);
mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;

-
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Next message: Richard B. Johnson: "Re: [CHECKER] Implementation inconsistencies in 2.6.3"
Previous message: Carl-Daniel Hailfinger: "Re: [PATCH] Blacklist binary-only modules lying about their license"
In reply to: Hugh Dickins: "[PATCH] rmap 17 real prio_tree"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]