[PATCH 1/7] Fragmentation Avoidance V19: 001_antidefrag_flags

Mel Gorman
2005-10-30T18:34:00Z

This patch adds two flags __GFP_EASYRCLM and __GFP_KERNRCLM that are used
to trap the type of allocation the caller is made. Allocations using
the __GFP_EASYRCLM flag are expected to be easily reclaimed by syncing
with backing storage (be it a file or swap) or cleaning the buffers and
discarding. Allocations using the __GFP_KERNRCLM flag belong to slab caches
that can be shrunk by the kernel.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/buffer.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/buffer.c
--- linux-2.6.14-rc5-mm1-clean/fs/buffer.c 2005-10-30 13:19:59.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/buffer.c 2005-10-30 13:34:50.000000000 +0000
@@ -1119,7 +1119,8 @@ grow_dev_page(struct block_device *bdev,
struct page *page;
struct buffer_head *bh;

- page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
+ page = find_or_create_page(inode->i_mapping, index,
+ GFP_NOFS|__GFP_EASYRCLM);
if (!page)
return NULL;

@@ -3058,7 +3059,8 @@ static void recalc_bh_state(void)

struct buffer_head *alloc_buffer_head(gfp_t gfp_flags)
{
- struct buffer_head *ret = kmem_cache_alloc(bh_cachep, gfp_flags);
+ struct buffer_head *ret = kmem_cache_alloc(bh_cachep,
+ gfp_flags|__GFP_KERNRCLM);
if (ret) {
get_cpu_var(bh_accounting).nr++;
recalc_bh_state();
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/compat.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/compat.c
--- linux-2.6.14-rc5-mm1-clean/fs/compat.c 2005-10-30 13:19:59.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/compat.c 2005-10-30 13:34:50.000000000 +0000
@@ -1363,7 +1363,7 @@ static int compat_copy_strings(int argc,
page = bprm->page[i];
new = 0;
if (!page) {
- page = alloc_page(GFP_HIGHUSER);
+ page = alloc_page(GFP_HIGHUSER|__GFP_EASYRCLM);
bprm->page[i] = page;
if (!page) {
ret = -ENOMEM;
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/dcache.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/dcache.c
--- linux-2.6.14-rc5-mm1-clean/fs/dcache.c 2005-10-30 13:19:59.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/dcache.c 2005-10-30 13:34:50.000000000 +0000
@@ -878,7 +878,7 @@ struct dentry *d_alloc(struct dentry * p
struct dentry *dentry;
char *dname;

- dentry = kmem_cache_alloc(dentry_cache, GFP_KERNEL);
+ dentry = kmem_cache_alloc(dentry_cache, GFP_KERNEL|__GFP_KERNRCLM);
if (!dentry)
return NULL;

diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/exec.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/exec.c
--- linux-2.6.14-rc5-mm1-clean/fs/exec.c 2005-10-30 13:19:59.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/exec.c 2005-10-30 13:34:50.000000000 +0000
@@ -237,7 +237,7 @@ static int copy_strings(int argc, char _
page = bprm->page[i];
new = 0;
if (!page) {
- page = alloc_page(GFP_HIGHUSER);
+ page = alloc_page(GFP_HIGHUSER|__GFP_EASYRCLM);
bprm->page[i] = page;
if (!page) {
ret = -ENOMEM;
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/ext2/super.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ext2/super.c
--- linux-2.6.14-rc5-mm1-clean/fs/ext2/super.c 2005-10-20 07:23:05.000000000 +0100
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ext2/super.c 2005-10-30 13:34:50.000000000 +0000
@@ -141,7 +141,8 @@ static kmem_cache_t * ext2_inode_cachep;
static struct inode *ext2_alloc_inode(struct super_block *sb)
{
struct ext2_inode_info *ei;
- ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, SLAB_KERNEL);
+ ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep,
+ SLAB_KERNEL|__GFP_KERNRCLM);
if (!ei)
return NULL;
#ifdef CONFIG_EXT2_FS_POSIX_ACL
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/ext3/super.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ext3/super.c
--- linux-2.6.14-rc5-mm1-clean/fs/ext3/super.c 2005-10-30 13:20:00.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ext3/super.c 2005-10-30 13:34:50.000000000 +0000
@@ -444,7 +444,7 @@ static struct inode *ext3_alloc_inode(st
{
struct ext3_inode_info *ei;

- ei = kmem_cache_alloc(ext3_inode_cachep, SLAB_NOFS);
+ ei = kmem_cache_alloc(ext3_inode_cachep, SLAB_NOFS|__GFP_KERNRCLM);
if (!ei)
return NULL;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/inode.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/inode.c
--- linux-2.6.14-rc5-mm1-clean/fs/inode.c 2005-10-20 07:23:05.000000000 +0100
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/inode.c 2005-10-30 13:34:50.000000000 +0000
@@ -146,7 +146,7 @@ static struct inode *alloc_inode(struct
mapping->a_ops = &empty_aops;
mapping->host = inode;
mapping->flags = 0;
- mapping_set_gfp_mask(mapping, GFP_HIGHUSER);
+ mapping_set_gfp_mask(mapping, GFP_HIGHUSER|__GFP_EASYRCLM);
mapping->assoc_mapping = NULL;
mapping->backing_dev_info = &default_backing_dev_info;

diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/fs/ntfs/inode.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ntfs/inode.c
--- linux-2.6.14-rc5-mm1-clean/fs/ntfs/inode.c 2005-10-30 13:20:01.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/fs/ntfs/inode.c 2005-10-30 13:34:50.000000000 +0000
@@ -318,7 +318,7 @@ struct inode *ntfs_alloc_big_inode(struc
ntfs_inode *ni;

ntfs_debug("Entering.");
- ni = kmem_cache_alloc(ntfs_big_inode_cache, SLAB_NOFS);
+ ni = kmem_cache_alloc(ntfs_big_inode_cache, SLAB_NOFS|__GFP_KERNRCLM);
if (likely(ni != NULL)) {
ni->state = 0;
return VFS_I(ni);
@@ -343,7 +343,7 @@ static inline ntfs_inode *ntfs_alloc_ext
ntfs_inode *ni;

ntfs_debug("Entering.");
- ni = kmem_cache_alloc(ntfs_inode_cache, SLAB_NOFS);
+ ni = kmem_cache_alloc(ntfs_inode_cache, SLAB_NOFS|__GFP_KERNRCLM);
if (likely(ni != NULL)) {
ni->state = 0;
return ni;
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/include/asm-i386/page.h linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/asm-i386/page.h
--- linux-2.6.14-rc5-mm1-clean/include/asm-i386/page.h 2005-10-20 07:23:05.000000000 +0100
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/asm-i386/page.h 2005-10-30 13:34:50.000000000 +0000
@@ -36,7 +36,8 @@
#define clear_user_page(page, vaddr, pg) clear_page(page)
#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)

-#define alloc_zeroed_user_highpage(vma, vaddr) alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO, vma, vaddr)
+#define alloc_zeroed_user_highpage(vma, vaddr) \
+ alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | __GFP_EASYRCLM, vma, vaddr)
#define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE

/*
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/include/linux/gfp.h linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/linux/gfp.h
--- linux-2.6.14-rc5-mm1-clean/include/linux/gfp.h 2005-10-30 13:20:05.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/linux/gfp.h 2005-10-30 13:34:50.000000000 +0000
@@ -50,14 +50,27 @@ struct vm_area_struct;
#define __GFP_HARDWALL 0x40000u /* Enforce hardwall cpuset memory allocs */
#define __GFP_VALID 0x80000000u /* valid GFP flags */

-#define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */
+/*
+ * Allocation type modifiers, these are required to be adjacent
+ * __GFP_EASYRCLM: Easily reclaimed pages like userspace or buffer pages
+ * __GFP_KERNRCLM: Short-lived or reclaimable kernel allocation
+ * Both bits off: Kernel non-reclaimable or very hard to reclaim
+ * __GFP_EASYRCLM and __GFP_KERNRCLM should not be specified at the same time
+ * RCLM_SHIFT (defined elsewhere) depends on the location of these bits
+ */
+#define __GFP_EASYRCLM 0x80000u /* User and other easily reclaimed pages */
+#define __GFP_KERNRCLM 0x100000u /* Kernel page that is reclaimable */
+#define __GFP_RCLM_BITS (__GFP_EASYRCLM|__GFP_KERNRCLM)
+
+#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */
#define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)

/* if you forget to add the bitmask here kernel will crash, period */
#define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
__GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
__GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
- __GFP_NOMEMALLOC|__GFP_NORECLAIM|__GFP_HARDWALL)
+ __GFP_NOMEMALLOC|__GFP_NORECLAIM|__GFP_HARDWALL| \
+ __GFP_EASYRCLM|__GFP_KERNRCLM)

#define GFP_ATOMIC (__GFP_VALID | __GFP_HIGH)
#define GFP_NOIO (__GFP_VALID | __GFP_WAIT)
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/include/linux/highmem.h linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/linux/highmem.h
--- linux-2.6.14-rc5-mm1-clean/include/linux/highmem.h 2005-10-20 07:23:05.000000000 +0100
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/include/linux/highmem.h 2005-10-30 13:34:50.000000000 +0000
@@ -47,7 +47,8 @@ static inline void clear_user_highpage(s
static inline struct page *
alloc_zeroed_user_highpage(struct vm_area_struct *vma, unsigned long vaddr)
{
- struct page *page = alloc_page_vma(GFP_HIGHUSER, vma, vaddr);
+ struct page *page = alloc_page_vma(GFP_HIGHUSER|__GFP_EASYRCLM,
+ vma, vaddr);

if (page)
clear_user_highpage(page, vaddr);
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/mm/memory.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/memory.c
--- linux-2.6.14-rc5-mm1-clean/mm/memory.c 2005-10-30 13:20:06.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/memory.c 2005-10-30 13:34:50.000000000 +0000
@@ -1295,7 +1295,8 @@ static int do_wp_page(struct mm_struct *
if (!new_page)
goto oom;
} else {
- new_page = alloc_page_vma(GFP_HIGHUSER, vma, address);
+ new_page = alloc_page_vma(GFP_HIGHUSER|__GFP_EASYRCLM,
+ vma, address);
if (!new_page)
goto oom;
copy_user_highpage(new_page, old_page, address);
@@ -1858,7 +1859,8 @@ retry:

if (unlikely(anon_vma_prepare(vma)))
goto oom;
- page = alloc_page_vma(GFP_HIGHUSER, vma, address);
+ page = alloc_page_vma(GFP_HIGHUSER|__GFP_EASYRCLM,
+ vma, address);
if (!page)
goto oom;
copy_user_highpage(page, new_page, address);
diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/mm/shmem.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/shmem.c
--- linux-2.6.14-rc5-mm1-clean/mm/shmem.c 2005-10-30 13:20:06.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/shmem.c 2005-10-30 13:34:50.000000000 +0000
@@ -906,7 +906,7 @@ shmem_alloc_page(unsigned long gfp, stru
pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
pvma.vm_pgoff = idx;
pvma.vm_end = PAGE_SIZE;
- page = alloc_page_vma(gfp | __GFP_ZERO, &pvma, 0);
+ page = alloc_page_vma(gfp | __GFP_ZERO | __GFP_EASYRCLM, &pvma, 0);
mpol_free(pvma.vm_policy);
return page;
}
@@ -921,7 +921,7 @@ shmem_swapin(struct shmem_inode_info *in
static inline struct page *
shmem_alloc_page(gfp_t gfp,struct shmem_inode_info *info, unsigned long idx)
{
- return alloc_page(gfp | __GFP_ZERO);
+ return alloc_page(gfp | __GFP_ZERO | __GFP_EASYRCLM);
}
#endif

diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-clean/mm/swap_state.c linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/swap_state.c
--- linux-2.6.14-rc5-mm1-clean/mm/swap_state.c 2005-10-30 13:20:06.000000000 +0000
+++ linux-2.6.14-rc5-mm1-001_antidefrag_flags/mm/swap_state.c 2005-10-30 13:34:50.000000000 +0000
@@ -341,7 +341,8 @@ struct page *read_swap_cache_async(swp_e
* Get a new page to read into from swap.
*/
if (!new_page) {
- new_page = alloc_page_vma(GFP_HIGHUSER, vma, addr);
+ new_page = alloc_page_vma(GFP_HIGHUSER|__GFP_EASYRCLM,
+ vma, addr);
if (!new_page)
break; /* Out of memory */
}