[PATCH V1] mm/damon: Modify damon_rand() macro to static inline function

From: Xin Hao
Date: Mon Dec 06 2021 - 07:41:39 EST


The damon_rand() func can not be implemented as a macro.
Example:
damon_rand(a++, b);
The value of 'a' will be incremented twice, This is obviously
unreasonable, So there fix it.

Fixes: b9a6ac4e4ede ("mm/damon: adaptively adjust regions")
Reported-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>
---
include/linux/damon.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index c6df025d8704..bc9c8932b1e8 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -19,7 +19,10 @@
#define DAMOS_MAX_SCORE (99)

/* Get a random number in [l, r) */
-#define damon_rand(l, r) (l + prandom_u32_max(r - l))
+static inline unsigned long damon_rand(unsigned long l, unsigned long r)
+{
+ return l + (r - l);
+}

/**
* struct damon_addr_range - Represents an address region of [@start, @end).
--
2.31.0