From: Christoph Lameter Subject: Move tlb flushing into free_pgtables Move the tlb flushing into free_pgtables. The conversion of the locks taken for reverse map scanning would require taking sleeping locks in free_pgtables. Moving the tlb flushing into free_pgtables allows sleeping in part of free_pgtables(). This means that we do a tlb_finish_mmu() before freeing the page tables. Strictly speaking there may not be the need to do another tlb flush after freeing the tables. But its the only way to free a series of pages from the tlb list. And we do not want to call into the page allocator for performance reasons. Signed-off-by: Christoph Lameter --- include/linux/mm.h | 4 ++-- mm/memory.c | 14 ++++++++++---- mm/mmap.c | 6 +++--- 3 files changed, 15 insertions(+), 9 deletions(-) Index: linux-2.6/include/linux/mm.h =================================================================== --- linux-2.6.orig/include/linux/mm.h 2008-03-19 13:30:51.460856986 -0700 +++ linux-2.6/include/linux/mm.h 2008-03-19 13:31:20.809377398 -0700 @@ -751,8 +751,8 @@ int walk_page_range(const struct mm_stru void *private); void free_pgd_range(struct mmu_gather **tlb, unsigned long addr, unsigned long end, unsigned long floor, unsigned long ceiling); -void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *start_vma, - unsigned long floor, unsigned long ceiling); +void free_pgtables(struct vm_area_struct *start_vma, unsigned long floor, + unsigned long ceiling); int copy_page_range(struct mm_struct *dst, struct mm_struct *src, struct vm_area_struct *vma); void unmap_mapping_range(struct address_space *mapping, Index: linux-2.6/mm/memory.c =================================================================== --- linux-2.6.orig/mm/memory.c 2008-03-19 13:29:06.007351495 -0700 +++ linux-2.6/mm/memory.c 2008-03-19 13:46:31.352774359 -0700 @@ -271,9 +271,11 @@ void free_pgd_range(struct mmu_gather ** } while (pgd++, addr = next, addr != end); } -void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *vma, - unsigned long floor, unsigned long ceiling) +void free_pgtables(struct vm_area_struct *vma, unsigned long floor, + unsigned long ceiling) { + struct mmu_gather *tlb; + while (vma) { struct vm_area_struct *next = vma->vm_next; unsigned long addr = vma->vm_start; @@ -285,8 +287,10 @@ void free_pgtables(struct mmu_gather **t unlink_file_vma(vma); if (is_vm_hugetlb_page(vma)) { - hugetlb_free_pgd_range(tlb, addr, vma->vm_end, + tlb = tlb_gather_mmu(vma->vm_mm, 0); + hugetlb_free_pgd_range(&tlb, addr, vma->vm_end, floor, next? next->vm_start: ceiling); + tlb_finish_mmu(tlb, addr, vma->vm_end); } else { /* * Optimization: gather nearby vmas into one call down @@ -298,8 +302,10 @@ void free_pgtables(struct mmu_gather **t anon_vma_unlink(vma); unlink_file_vma(vma); } - free_pgd_range(tlb, addr, vma->vm_end, + tlb = tlb_gather_mmu(vma->vm_mm, 0); + free_pgd_range(&tlb, addr, vma->vm_end, floor, next? next->vm_start: ceiling); + tlb_finish_mmu(tlb, addr, vma->vm_end); } vma = next; } Index: linux-2.6/mm/mmap.c =================================================================== --- linux-2.6.orig/mm/mmap.c 2008-03-19 13:29:48.659889667 -0700 +++ linux-2.6/mm/mmap.c 2008-03-19 13:30:36.296604891 -0700 @@ -1750,9 +1750,9 @@ static void unmap_region(struct mm_struc update_hiwater_rss(mm); unmap_vmas(&tlb, vma, start, end, &nr_accounted, NULL); vm_unacct_memory(nr_accounted); - free_pgtables(&tlb, vma, prev? prev->vm_end: FIRST_USER_ADDRESS, - next? next->vm_start: 0); tlb_finish_mmu(tlb, start, end); + free_pgtables(vma, prev? prev->vm_end: FIRST_USER_ADDRESS, + next? next->vm_start: 0); emm_notify(mm, emm_invalidate_end, start, end); } @@ -2049,8 +2049,8 @@ void exit_mmap(struct mm_struct *mm) /* Use -1 here to ensure all VMAs in the mm are unmapped */ end = unmap_vmas(&tlb, vma, 0, -1, &nr_accounted, NULL); vm_unacct_memory(nr_accounted); - free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, 0); tlb_finish_mmu(tlb, 0, end); + free_pgtables(vma, FIRST_USER_ADDRESS, 0); /* * Walk the list again, actually closing and freeing it,