The tmpfs superblock grants an offset for each inode as they are created. Each
inode then uses that offset to provide a preferred first node for its interleave
in the shmem_interleave.
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Lee Schermerhorn <lee.schermerhorn@xxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Nathan T Zimmer <nzimmer@xxxxxxx>
---
include/linux/mm.h | 6 ++++++
include/linux/shmem_fs.h | 2 ++
mm/mempolicy.c | 4 ++++
mm/shmem.c | 14 ++++++++++++++
4 files changed, 26 insertions(+), 0 deletions(-)
Index: linux/include/linux/mm.h
===================================================================
--- linux.orig/include/linux/mm.h 2012-07-02 10:38:25.090169183 -0500
+++ linux/include/linux/mm.h 2012-07-02 10:38:30.714072182 -0500
@@ -238,6 +238,12 @@ struct vm_operations_struct {
*/
struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
unsigned long addr);
+
+ /*
+ * If the policy is interleave allow the vma to suggest a node.
+ */
+ unsigned long (*interleave)( struct vm_area_struct *vma, unsigned long addr);
+
int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
const nodemask_t *to, unsigned long flags);
#endif
Index: linux/include/linux/shmem_fs.h
===================================================================
--- linux.orig/include/linux/shmem_fs.h 2012-07-02 10:38:25.090169183 -0500
+++ linux/include/linux/shmem_fs.h 2012-07-02 10:38:30.714072182 -0500
@@ -17,6 +17,7 @@ struct shmem_inode_info {
char *symlink; /* unswappable short symlink */
};
struct shared_policy policy; /* NUMA memory alloc policy */
+ unsigned long node_offset; /* bias for interleaved nodes */
struct list_head swaplist; /* chain of maybes on swap */
struct list_head xattr_list; /* list of shmem_xattr */
struct inode vfs_inode;
@@ -32,6 +33,7 @@ struct shmem_sb_info {
kgid_t gid; /* Mount gid for root directory */
umode_t mode; /* Mount mode for root directory */
struct mempolicy *mpol; /* default memory policy for mappings */
+ unsigned long next_pref_node; /* next interleave bias to suggest for inodes */
};
static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
Index: linux/mm/mempolicy.c
===================================================================
--- linux.orig/mm/mempolicy.c 2012-07-02 10:38:25.090169183 -0500
+++ linux/mm/mempolicy.c 2012-07-02 10:38:30.738071768 -0500
@@ -1663,6 +1663,10 @@ static inline unsigned interleave_nid(st
{
if (vma) {
unsigned long off;
+ if (vma->vm_ops && vma->vm_ops->interleave) {
+ off = vma->vm_ops->interleave( vma, addr );
+ return offset_il_node(pol, vma, off );
+ }
/*
* for small pages, there is no difference between
Index: linux/mm/shmem.c
===================================================================
--- linux.orig/mm/shmem.c 2012-07-02 10:38:25.090169183 -0500
+++ linux/mm/shmem.c 2012-07-02 10:40:44.635767155 -0500
@@ -922,6 +922,7 @@ static struct page *shmem_swapin(swp_ent
pvma.vm_start = 0;
pvma.vm_pgoff = index;
pvma.vm_policy = spol;
+ pvma.vm_private_data = (void*)info->node_offset;
if( pvma.vm_policy )
pvma.vm_ops = &shmem_vm_ops;
else
@@ -938,6 +939,7 @@ static struct page *shmem_alloc_page(gfp
pvma.vm_start = 0;
pvma.vm_pgoff = index;
pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, index);
+ pvma.vm_private_data = (void*)info->node_offset;
if( pvma.vm_policy )
pvma.vm_ops = &shmem_vm_ops;
else
@@ -1314,6 +1316,18 @@ static struct mempolicy *shmem_get_polic
index = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy, index);
}
+
+static unsigned long shmem_interleave( struct vm_area_struct *vma, unsigned long addr)
+{
+ unsigned offset;
+
+ // Use the vm_files prefered node as the initial offset
+ offset = (unsigned long)vma->vm_private_data;
+
+ offset += ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+
+ return offset;
+}
#endif
int shmem_lock(struct file *file, int lock, struct user_struct *user)
@@ -2871,6 +2885,7 @@ static const struct super_operations shm
static const struct vm_operations_struct shmem_vm_ops = {
.fault = shmem_fault,
#ifdef CONFIG_NUMA
+ .interleave = shmem_interleave,
.set_policy = shmem_set_policy,
.get_policy = shmem_get_policy,
#endif
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>