diff options
Diffstat (limited to 'Documentation/vm/unevictable-lru.txt')
| -rw-r--r-- | Documentation/vm/unevictable-lru.txt | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt index fa206cccf89..a68db7692ee 100644 --- a/Documentation/vm/unevictable-lru.txt +++ b/Documentation/vm/unevictable-lru.txt @@ -197,12 +197,8 @@ the pages are also "rescued" from the unevictable list in the process of freeing them. page_evictable() also checks for mlocked pages by testing an additional page -flag, PG_mlocked (as wrapped by PageMlocked()). If the page is NOT mlocked, -and a non-NULL VMA is supplied, page_evictable() will check whether the VMA is -VM_LOCKED via is_mlocked_vma(). is_mlocked_vma() will SetPageMlocked() and -update the appropriate statistics if the vma is VM_LOCKED. This method allows -efficient "culling" of pages in the fault path that are being faulted in to -VM_LOCKED VMAs. +flag, PG_mlocked (as wrapped by PageMlocked()), which is set when a page is +faulted into a VM_LOCKED vma, or found in a vma being VM_LOCKED. VMSCAN'S HANDLING OF UNEVICTABLE PAGES @@ -371,8 +367,8 @@ mlock_fixup() filters several classes of "special" VMAs: mlock_fixup() will call make_pages_present() in the hugetlbfs VMA range to allocate the huge pages and populate the ptes. -3) VMAs with VM_DONTEXPAND or VM_RESERVED are generally userspace mappings of - kernel pages, such as the VDSO page, relay channel pages, etc. These pages +3) VMAs with VM_DONTEXPAND are generally userspace mappings of kernel pages, + such as the VDSO page, relay channel pages, etc. These pages are inherently unevictable and are not managed on the LRU lists. mlock_fixup() treats these VMAs the same as hugetlbfs VMAs. It calls make_pages_present() to populate the ptes. @@ -651,7 +647,7 @@ PAGE RECLAIM IN shrink_*_list() ------------------------------- shrink_active_list() culls any obviously unevictable pages - i.e. -!page_evictable(page, NULL) - diverting these to the unevictable list. +!page_evictable(page) - diverting these to the unevictable list. However, shrink_active_list() only sees unevictable pages that made it onto the active/inactive lru lists. Note that these pages do not have PageUnevictable set - otherwise they would be on the unevictable list and shrink_active_list |