From: Gao Xiang <hsiangkao@aol.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Fengguang Wu <fengguang.wu@intel.com>,
Gao Xiang <hsiangkao@aol.com>
Subject: [PATCH] mm: simplify get_next_ra_size
Date: Sun, 28 Oct 2018 14:13:26 +0800 [thread overview]
Message-ID: <1540707206-19649-1-git-send-email-hsiangkao@aol.com> (raw)
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.
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Gao Xiang <hsiangkao@aol.com>
---
mm/readahead.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/mm/readahead.c b/mm/readahead.c
index 4e63014..205ac34 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -272,17 +272,15 @@ 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;
}
/*
--
2.7.4
next reply other threads:[~2018-10-28 6:14 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-28 6:13 Gao Xiang [this message]
2018-10-28 6:27 ` [PATCH] mm: simplify get_next_ra_size Fengguang Wu
2018-10-28 7:05 ` Gao Xiang
2018-10-28 10:23 ` Matthew Wilcox
2018-10-28 11:05 ` Gao Xiang
2020-11-02 19:01 The Dellia’s
2020-11-02 21:00 ` The Dellia’s
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