mm/readahead.c: simplify get_next_ra_size()
It's a trivial simplification for get_next_ra_size() and clear enough for
humans to understand.
It also fixes potential overflow if ra->size(< ra_pages) is too large.
Link: http://lkml.kernel.org/r/1540707206-19649-1-git-send-email-hsiangkao@aol.com
Signed-off-by: Gao Xiang <hsiangkao@aol.com>
Reviewed-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/readahead.c b/mm/readahead.c
index f3d6f96..1ae1652 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -270,17 +270,15 @@ static unsigned long get_init_ra_size(unsigned long size, unsigned long max)
* return it as the new window size.
*/
static unsigned long get_next_ra_size(struct file_ra_state *ra,
- unsigned long max)
+ unsigned long max)
{
unsigned long cur = ra->size;
- unsigned long newsize;
if (cur < max / 16)
- newsize = 4 * cur;
- else
- newsize = 2 * cur;
-
- return min(newsize, max);
+ return 4 * cur;
+ if (cur <= max / 2)
+ return 2 * cur;
+ return max;
}
/*
