Thread (49 messages) 49 messages, 5 authors, 2012-06-24

Re: [PATCH -V9 04/15] hugetlb: use mmu_gather instead of a temporary linked list for accumulating pages

From: Michal Hocko <hidden>
Date: 2012-06-14 07:16:39
Also in: linux-mm, lkml

On Wed 13-06-12 22:07:06, Aneesh Kumar K.V wrote:
Michal Hocko [off-list ref] writes:
quoted
On Wed 13-06-12 15:57:23, Aneesh Kumar K.V wrote:
quoted
From: "Aneesh Kumar K.V" <redacted>

Use a mmu_gather instead of a temporary linked list for accumulating
pages when we unmap a hugepage range
Sorry for coming up with the comment that late but you owe us an
explanation _why_ you are doing this.

I assume that this fixes a real problem when we take i_mmap_mutex
already up in 
unmap_mapping_range
  mutex_lock(&mapping->i_mmap_mutex);
  unmap_mapping_range_tree | unmap_mapping_range_list 
    unmap_mapping_range_vma
      zap_page_range_single
        unmap_single_vma
	  unmap_hugepage_range
	    mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex);

And that this should have been marked for stable as well (I haven't
checked when this has been introduced).
Switch to mmu_gather is to get rid of the use of page->lru so that i can use it for
active list.
So can we get this to the changelog please?

-- 
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9    
Czech Republic
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help