mm: search from free_area_cache for the bigger size

[mv-sheeva.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index da15a79b1441b665b0e4b962eea38a92407018fd..9e0c0de2e7e38c5735cfe27d35bee09f0453b6e3 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1426,10 +1426,8 @@ void arch_unmap_area(struct mm_struct *mm, unsigned long addr)
        /*
         * Is this a new hole at the lowest possible address?
         */
-       if (addr >= TASK_UNMAPPED_BASE && addr < mm->free_area_cache) {
+       if (addr >= TASK_UNMAPPED_BASE && addr < mm->free_area_cache)
                mm->free_area_cache = addr;
-               mm->cached_hole_size = ~0UL;
-       }
 }
 
 /*
@@ -1444,7 +1442,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 {
        struct vm_area_struct *vma;
        struct mm_struct *mm = current->mm;
-       unsigned long addr = addr0;
+       unsigned long addr = addr0, start_addr;
 
        /* requested length too big for entire address space */
        if (len > TASK_SIZE)
@@ -1468,22 +1466,14 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
                mm->free_area_cache = mm->mmap_base;
        }
 
+try_again:
        /* either no address requested or can't fit in requested address hole */
-       addr = mm->free_area_cache;
-
-       /* make sure it can fit in the remaining address space */
-       if (addr > len) {
-               vma = find_vma(mm, addr-len);
-               if (!vma || addr <= vma->vm_start)
-                       /* remember the address as a hint for next time */
-                       return (mm->free_area_cache = addr-len);
-       }
-
-       if (mm->mmap_base < len)
-               goto bottomup;
+       start_addr = addr = mm->free_area_cache;
 
-       addr = mm->mmap_base-len;
+       if (addr < len)
+               goto fail;
 
+       addr -= len;
        do {
                /*
                 * Lookup failure means no vma is above this address,
@@ -1503,7 +1493,21 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
                addr = vma->vm_start-len;
        } while (len < vma->vm_start);
 
-bottomup:
+fail:
+       /*
+        * if hint left us with no space for the requested
+        * mapping then try again:
+        *
+        * Note: this is different with the case of bottomup
+        * which does the fully line-search, but we use find_vma
+        * here that causes some holes skipped.
+        */
+       if (start_addr != mm->mmap_base) {
+               mm->free_area_cache = mm->mmap_base;
+               mm->cached_hole_size = 0;
+               goto try_again;
+       }
+
        /*
         * A failed mmap() very likely causes application failure,
         * so fall back to the bottom-up function here. This scenario