From: Michel Lespinasse Date: Fri, 9 Nov 2012 03:04:25 +0000 (+1100) Subject: mm: use vm_unmapped_area() in hugetlbfs on i386 architecture X-Git-Tag: next-20121113~6^2~174 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=17ab8963b4034943be11848637879c5ec6855e56;p=karo-tx-linux.git mm: use vm_unmapped_area() in hugetlbfs on i386 architecture Update the i386 hugetlb_get_unmapped_area function to make use of vm_unmapped_area() instead of implementing a brute force search. Signed-off-by: Michel Lespinasse Reviewed-by: Rik van Riel Cc: Hugh Dickins Cc: Russell King Cc: Ralf Baechle Cc: Paul Mundt Cc: "David S. Miller" Cc: Chris Metcalf Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton --- diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index 937bff5cdaa7..c00c4a4cd564 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -274,42 +274,15 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file, unsigned long pgoff, unsigned long flags) { struct hstate *h = hstate_file(file); - struct mm_struct *mm = current->mm; - struct vm_area_struct *vma; - unsigned long start_addr; - - if (len > mm->cached_hole_size) { - start_addr = mm->free_area_cache; - } else { - start_addr = TASK_UNMAPPED_BASE; - mm->cached_hole_size = 0; - } - -full_search: - addr = ALIGN(start_addr, huge_page_size(h)); - - for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { - /* At this point: (!vma || addr < vma->vm_end). */ - if (TASK_SIZE - len < addr) { - /* - * Start a new search - just in case we missed - * some holes. - */ - if (start_addr != TASK_UNMAPPED_BASE) { - start_addr = TASK_UNMAPPED_BASE; - mm->cached_hole_size = 0; - goto full_search; - } - return -ENOMEM; - } - if (!vma || addr + len <= vma->vm_start) { - 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 = ALIGN(vma->vm_end, huge_page_size(h)); - } + struct vm_unmapped_area_info info; + + info.flags = 0; + info.length = len; + info.low_limit = TASK_UNMAPPED_BASE; + info.high_limit = TASK_SIZE; + info.align_mask = PAGE_MASK & ~huge_page_mask(h); + info.align_offset = 0; + return vm_unmapped_area(&info); } static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, @@ -317,83 +290,30 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long pgoff, unsigned long flags) { struct hstate *h = hstate_file(file); - struct mm_struct *mm = current->mm; - struct vm_area_struct *vma; - unsigned long base = mm->mmap_base; - unsigned long addr = addr0; - unsigned long largest_hole = mm->cached_hole_size; - unsigned long start_addr; - - /* don't allow allocations above current base */ - if (mm->free_area_cache > base) - mm->free_area_cache = base; - - if (len <= largest_hole) { - largest_hole = 0; - mm->free_area_cache = base; - } -try_again: - start_addr = mm->free_area_cache; - - /* make sure it can fit in the remaining address space */ - if (mm->free_area_cache < len) - goto fail; - - /* either no address requested or can't fit in requested address hole */ - addr = (mm->free_area_cache - len) & huge_page_mask(h); - do { - /* - * Lookup failure means no vma is above this address, - * i.e. return with success: - */ - vma = find_vma(mm, addr); - if (!vma) - return addr; + struct vm_unmapped_area_info info; + unsigned long addr; - if (addr + len <= vma->vm_start) { - /* remember the address as a hint for next time */ - mm->cached_hole_size = largest_hole; - return (mm->free_area_cache = addr); - } else if (mm->free_area_cache == vma->vm_end) { - /* pull free_area_cache down to the first hole */ - mm->free_area_cache = vma->vm_start; - mm->cached_hole_size = largest_hole; - } + info.flags = VM_UNMAPPED_AREA_TOPDOWN; + info.length = len; + info.low_limit = PAGE_SIZE; + info.high_limit = mm->mmap_base; + info.align_mask = PAGE_MASK & ~huge_page_mask(h); + info.align_offset = 0; + addr = vm_unmapped_area(&info); - /* remember the largest hole we saw so far */ - if (addr + largest_hole < vma->vm_start) - largest_hole = vma->vm_start - addr; - - /* try just below the current vma->vm_start */ - addr = (vma->vm_start - len) & huge_page_mask(h); - } while (len <= vma->vm_start); - -fail: - /* - * if hint left us with no space for the requested - * mapping then try again: - */ - if (start_addr != base) { - mm->free_area_cache = base; - largest_hole = 0; - goto try_again; - } /* * A failed mmap() very likely causes application failure, * so fall back to the bottom-up function here. This scenario * can happen with large stack limits and large mmap() * allocations. */ - mm->free_area_cache = TASK_UNMAPPED_BASE; - mm->cached_hole_size = ~0UL; - addr = hugetlb_get_unmapped_area_bottomup(file, addr0, - len, pgoff, flags); - - /* - * Restore the topdown base: - */ - mm->free_area_cache = base; - mm->cached_hole_size = ~0UL; + if (addr & ~PAGE_MASK) { + VM_BUG_ON(addr != -ENOMEM); + info.flags = 0; + info.low_limit = TASK_UNMAPPED_BASE; + info.high_limit = TASK_SIZE; + addr = vm_unmapped_area(&info); + } return addr; }