[PATCH] fix free swap cache latency

[linux-2.6-omap-h63xx.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index d8dde07a36566fc6463b7b9b95305d9b0505427e..85e80a57db29e2412ef766268996ec005c3e16c8 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -82,6 +82,16 @@ EXPORT_SYMBOL(num_physpages);
 EXPORT_SYMBOL(high_memory);
 EXPORT_SYMBOL(vmalloc_earlyreserve);
 
+int randomize_va_space __read_mostly = 1;
+
+static int __init disable_randmaps(char *s)
+{
+       randomize_va_space = 0;
+       return 0;
+}
+__setup("norandmaps", disable_randmaps);
+
+
 /*
  * If a p?d_bad entry is found while walking page tables, report
  * the error, before resetting entry to p?d_none.  Usually (but
@@ -613,11 +623,12 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
                        (*zap_work)--;
                        continue;
                }
+
+               (*zap_work) -= PAGE_SIZE;
+
                if (pte_present(ptent)) {
                        struct page *page;
 
-                       (*zap_work) -= PAGE_SIZE;
-
                        page = vm_normal_page(vma, addr, ptent);
                        if (unlikely(details) && page) {
                                /*
@@ -1498,7 +1509,7 @@ gotten:
                update_mmu_cache(vma, address, entry);
                lazy_mmu_prot_update(entry);
                lru_cache_add_active(new_page);
-               page_add_anon_rmap(new_page, vma, address);
+               page_add_new_anon_rmap(new_page, vma, address);
 
                /* Free the old page.. */
                new_page = old_page;
@@ -1770,9 +1781,32 @@ out_big:
 out_busy:
        return -ETXTBSY;
 }
-
 EXPORT_SYMBOL(vmtruncate);
 
+int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
+{
+       struct address_space *mapping = inode->i_mapping;
+
+       /*
+        * If the underlying filesystem is not going to provide
+        * a way to truncate a range of blocks (punch a hole) -
+        * we should return failure right now.
+        */
+       if (!inode->i_op || !inode->i_op->truncate_range)
+               return -ENOSYS;
+
+       mutex_lock(&inode->i_mutex);
+       down_write(&inode->i_alloc_sem);
+       unmap_mapping_range(mapping, offset, (end - offset), 1);
+       truncate_inode_pages_range(mapping, offset, end);
+       inode->i_op->truncate_range(inode, offset, end);
+       up_write(&inode->i_alloc_sem);
+       mutex_unlock(&inode->i_mutex);
+
+       return 0;
+}
+EXPORT_SYMBOL(vmtruncate_range);
+
 /* 
  * Primitive swap readahead code. We simply read an aligned block of
  * (1 << page_cluster) entries in the swap area. This method is chosen
@@ -1848,6 +1882,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
                goto out;
 
        entry = pte_to_swp_entry(orig_pte);
+again:
        page = lookup_swap_cache(entry);
        if (!page) {
                swapin_readahead(entry, address, vma);
@@ -1871,6 +1906,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 
        mark_page_accessed(page);
        lock_page(page);
+       if (!PageSwapCache(page)) {
+               /* Page migration has occured */
+               unlock_page(page);
+               page_cache_release(page);
+               goto again;
+       }
 
        /*
         * Back out if somebody else already faulted in this pte.
@@ -1954,8 +1995,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
                        goto release;
                inc_mm_counter(mm, anon_rss);
                lru_cache_add_active(page);
-               SetPageReferenced(page);
-               page_add_anon_rmap(page, vma, address);
+               page_add_new_anon_rmap(page, vma, address);
        } else {
                /* Map the ZERO_PAGE - vm_page_prot is readonly */
                page = ZERO_PAGE(address);
@@ -2086,7 +2126,7 @@ retry:
                if (anon) {
                        inc_mm_counter(mm, anon_rss);
                        lru_cache_add_active(new_page);
-                       page_add_anon_rmap(new_page, vma, address);
+                       page_add_new_anon_rmap(new_page, vma, address);
                } else {
                        inc_mm_counter(mm, file_rss);
                        page_add_file_rmap(new_page);
@@ -2245,6 +2285,8 @@ int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
 }
 
+EXPORT_SYMBOL_GPL(__handle_mm_fault);
+
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * Allocate page upper directory.