[PATCH] Avoiding mmap fragmentation

[linux-2.6] / arch / sh / kernel / sys_sh.c

diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
index df5ac294c37906cd575a9bd482b2478cdfbd4805..917b2f32f260888b2a84b272303edce8d0b5c1b6 100644 (file)
--- a/arch/sh/kernel/sys_sh.c
+++ b/arch/sh/kernel/sys_sh.c
@@ -79,6 +79,10 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
                    (!vma || addr + len <= vma->vm_start))
                        return addr;
        }
+       if (len <= mm->cached_hole_size) {
+               mm->cached_hole_size = 0;
+               mm->free_area_cache = TASK_UNMAPPED_BASE;
+       }
        if (flags & MAP_PRIVATE)
                addr = PAGE_ALIGN(mm->free_area_cache);
        else
@@ -95,6 +99,7 @@ full_search:
                         */
                        if (start_addr != TASK_UNMAPPED_BASE) {
                                start_addr = addr = TASK_UNMAPPED_BASE;
+                               mm->cached_hole_size = 0;
                                goto full_search;
                        }
                        return -ENOMEM;
@@ -106,6 +111,9 @@ full_search:
                        mm->free_area_cache = addr + len;
                        return addr;
                }
+               if (addr + mm->cached_hole_size < vma->vm_start)
+                       mm->cached_hole_size = vma->vm_start - addr;
+
                addr = vma->vm_end;
                if (!(flags & MAP_PRIVATE))
                        addr = COLOUR_ALIGN(addr);