mm/page_alloc.c: fix a misleading comment
The comment says that the per-cpu batchsize and zone watermarks are
determined by present_pages which is definitely wrong, they are both
calculated from managed_pages. Fix it.
Signed-off-by: Yaowei Bai <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 9c3f2f8..a4482fc 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -349,7 +349,7 @@
(i < j):
zone[i]->protection[j]
- = (total sums of present_pages from zone[i+1] to zone[j] on the node)
+ = (total sums of managed_pages from zone[i+1] to zone[j] on the node)
/ lowmem_reserve_ratio[i];
(i = j):
(should not be protected. = 0;
@@ -360,7 +360,7 @@
256 (if zone[i] means DMA or DMA32 zone)
32 (others).
As above expression, they are reciprocal number of ratio.
-256 means 1/256. # of protection pages becomes about "0.39%" of total present
+256 means 1/256. # of protection pages becomes about "0.39%" of total managed
pages of higher zones on the node.
If you would like to protect more pages, smaller values are effective.
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index bdaa0cf..59abb47 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6022,7 +6022,7 @@
* set_dma_reserve - set the specified number of pages reserved in the first zone
* @new_dma_reserve: The number of pages to mark reserved
*
- * The per-cpu batchsize and zone watermarks are determined by present_pages.
+ * The per-cpu batchsize and zone watermarks are determined by managed_pages.
* In the DMA zone, a significant percentage may be consumed by kernel image
* and other unfreeable allocations which can skew the watermarks badly. This
* function may optionally be used to account for unfreeable pages in the
