fib_trie: Optimize fib_table_insert

[cascardo/linux.git] / mm / fadvise.c

diff --git a/mm/fadvise.c b/mm/fadvise.c
index 3bcfd81..2ad7adf 100644 (file)
--- a/mm/fadvise.c
+++ b/mm/fadvise.c
@@ -117,7 +117,11 @@ SYSCALL_DEFINE4(fadvise64_64, int, fd, loff_t, offset, loff_t, len, int, advice)
                        __filemap_fdatawrite_range(mapping, offset, endbyte,
                                                   WB_SYNC_NONE);
 
-               /* First and last FULL page! */
+               /*
+                * First and last FULL page! Partial pages are deliberately
+                * preserved on the expectation that it is better to preserve
+                * needed memory than to discard unneeded memory.
+                */
                start_index = (offset+(PAGE_CACHE_SIZE-1)) >> PAGE_CACHE_SHIFT;
                end_index = (endbyte >> PAGE_CACHE_SHIFT);