diff options
Diffstat (limited to 'Documentation/vm/unevictable-lru.txt')
| -rw-r--r-- | Documentation/vm/unevictable-lru.txt | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt index 97bae3c..fa206cc 100644 --- a/Documentation/vm/unevictable-lru.txt +++ b/Documentation/vm/unevictable-lru.txt @@ -538,7 +538,7 @@ different reverse map mechanisms. process because mlocked pages are migratable. However, for reclaim, if the page is mapped into a VM_LOCKED VMA, the scan stops. - try_to_unmap_anon() attempts to acquire in read mode the mmap semphore of + try_to_unmap_anon() attempts to acquire in read mode the mmap semaphore of the mm_struct to which the VMA belongs. If this is successful, it will mlock the page via mlock_vma_page() - we wouldn't have gotten to try_to_unmap_anon() if the page were already mlocked - and will return @@ -619,11 +619,11 @@ all PTEs from the page. For this purpose, the unevictable/mlock infrastructure introduced a variant of try_to_unmap() called try_to_munlock(). try_to_munlock() calls the same functions as try_to_unmap() for anonymous and -mapped file pages with an additional argument specifing unlock versus unmap +mapped file pages with an additional argument specifying unlock versus unmap processing. Again, these functions walk the respective reverse maps looking for VM_LOCKED VMAs. When such a VMA is found for anonymous pages and file pages mapped in linear VMAs, as in the try_to_unmap() case, the functions -attempt to acquire the associated mmap semphore, mlock the page via +attempt to acquire the associated mmap semaphore, mlock the page via mlock_vma_page() and return SWAP_MLOCK. This effectively undoes the pre-clearing of the page's PG_mlocked done by munlock_vma_page. @@ -641,7 +641,7 @@ with it - the usual fallback position. Note that try_to_munlock()'s reverse map walk must visit every VMA in a page's reverse map to determine that a page is NOT mapped into any VM_LOCKED VMA. However, the scan can terminate when it encounters a VM_LOCKED VMA and can -successfully acquire the VMA's mmap semphore for read and mlock the page. +successfully acquire the VMA's mmap semaphore for read and mlock the page. Although try_to_munlock() might be called a great many times when munlocking a large region or tearing down a large address space that has been mlocked via mlockall(), overall this is a fairly rare event. |
