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-rw-r--r--Documentation/vm/unevictable-lru.txt14
1 files changed, 5 insertions, 9 deletions
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt
index fa206cc..a68db769 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