Re: [RFC][PATCH 3/3] Covert objrmap to use prio_tree...

[Rajesh Venkatasubramanian <vrajesh@umich.edu>]

Convert mm/rmap.c to prio_tree...



 mm/rmap.c |   50 +++++++++++++++++++++++++++++++++++++++++++-------
 1 files changed, 43 insertions(+), 7 deletions(-)

diff -puN mm/rmap.c~objrmap_prio_tree mm/rmap.c
--- mmlinux-2.6/mm/rmap.c~objrmap_prio_tree	2004-03-21 16:25:12.000000000 -0500
+++ mmlinux-2.6-jaya/mm/rmap.c	2004-03-21 16:25:12.000000000 -0500
@@ -129,7 +129,7 @@ find_pte(struct vm_area_struct *vma, str
 	loffset = (page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT));
 	address = vma->vm_start + ((loffset - vma->vm_pgoff) << PAGE_SHIFT);
 	if (address < vma->vm_start || address >= vma->vm_end)
-		goto out;
+		BUG();

 	pgd = pgd_offset(mm, address);
 	if (!pgd_present(*pgd))
@@ -207,6 +207,8 @@ page_referenced_obj(struct page *page)
 {
 	struct address_space *mapping = page->mapping;
 	struct vm_area_struct *vma;
+	struct prio_tree_iter iter;
+	unsigned long loffset;
 	int referenced = 0;

 	if (!page->pte.mapcount)
@@ -221,11 +223,22 @@ page_referenced_obj(struct page *page)
 	if (down_trylock(&mapping->i_shared_sem))
 		return 1;

-	list_for_each_entry(vma, &mapping->i_mmap, shared)
+	loffset = (page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT));
+
+	vma = __vma_prio_tree_first(&mapping->i_mmap, &iter, loffset, loffset);
+	while (vma) {
 		referenced += page_referenced_obj_one(vma, page);
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap, &iter,
+				loffset, loffset);
+	}

-	list_for_each_entry(vma, &mapping->i_mmap_shared, shared)
+	vma = __vma_prio_tree_first(&mapping->i_mmap_shared, &iter, loffset,
+			loffset);
+	while (vma) {
 		referenced += page_referenced_obj_one(vma, page);
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap_shared, &iter,
+				loffset, loffset);
+	}

 	up(&mapping->i_shared_sem);

@@ -511,6 +524,8 @@ try_to_unmap_obj(struct page *page)
 {
 	struct address_space *mapping = page->mapping;
 	struct vm_area_struct *vma;
+	struct prio_tree_iter iter;
+	unsigned long loffset;
 	int ret = SWAP_AGAIN;

 	if (!mapping)
@@ -522,16 +537,25 @@ try_to_unmap_obj(struct page *page)
 	if (down_trylock(&mapping->i_shared_sem))
 		return ret;

-	list_for_each_entry(vma, &mapping->i_mmap, shared) {
+	loffset = (page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT));
+
+	vma = __vma_prio_tree_first(&mapping->i_mmap, &iter, loffset, loffset);
+	while (vma) {
 		ret = try_to_unmap_obj_one(vma, page);
 		if (ret == SWAP_FAIL || !page->pte.mapcount)
 			goto out;
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap, &iter,
+				loffset, loffset);
 	}

-	list_for_each_entry(vma, &mapping->i_mmap_shared, shared) {
+	vma = __vma_prio_tree_first(&mapping->i_mmap_shared, &iter, loffset,
+			loffset);
+	while (vma) {
 		ret = try_to_unmap_obj_one(vma, page);
 		if (ret == SWAP_FAIL || !page->pte.mapcount)
 			goto out;
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap_shared, &iter,
+				loffset, loffset);
 	}

 out:
@@ -749,6 +773,8 @@ int page_convert_anon(struct page *page)
 	struct address_space *mapping;
 	struct vm_area_struct *vma;
 	struct pte_chain *pte_chain = NULL;
+	struct prio_tree_iter iter;
+	unsigned long loffset;
 	pte_t *pte;
 	int err = 0;

@@ -783,7 +809,10 @@ int page_convert_anon(struct page *page)
 	 */
 	pte_chain_unlock(page);

-	list_for_each_entry(vma, &mapping->i_mmap, shared) {
+	loffset = (page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT));
+
+	vma = __vma_prio_tree_first(&mapping->i_mmap, &iter, loffset, loffset);
+	while (vma) {
 		if (!pte_chain) {
 			pte_chain = pte_chain_alloc(GFP_KERNEL);
 			if (!pte_chain) {
@@ -800,8 +829,13 @@ int page_convert_anon(struct page *page)
 			pte_unmap(pte);
 		}
 		spin_unlock(&vma->vm_mm->page_table_lock);
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap, &iter,
+				loffset, loffset);
 	}
-	list_for_each_entry(vma, &mapping->i_mmap_shared, shared) {
+
+	vma = __vma_prio_tree_first(&mapping->i_mmap_shared, &iter, loffset,
+			loffset);
+	while (vma) {
 		if (!pte_chain) {
 			pte_chain = pte_chain_alloc(GFP_KERNEL);
 			if (!pte_chain) {
@@ -818,6 +852,8 @@ int page_convert_anon(struct page *page)
 			pte_unmap(pte);
 		}
 		spin_unlock(&vma->vm_mm->page_table_lock);
+		vma = __vma_prio_tree_next(vma, &mapping->i_mmap_shared, &iter,
+				loffset, loffset);
 	}

 out_unlock:

_