dm: use time_in_range() and time_after()

To be future-proof and for better readability the time comparisons are modified
to use time_in_range() and time_after() instead of plain, error-prone math.

Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 4934789..0f78145 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -11,6 +11,7 @@
 #include <linux/device-mapper.h>
 #include <linux/dm-io.h>
 #include <linux/dm-kcopyd.h>
+#include <linux/jiffies.h>
 #include <linux/log2.h>
 #include <linux/list.h>
 #include <linux/rculist.h>
@@ -1700,8 +1701,8 @@
  */
 static int need_commit_due_to_time(struct pool *pool)
 {
-	return jiffies < pool->last_commit_jiffies ||
-	       jiffies > pool->last_commit_jiffies + COMMIT_PERIOD;
+	return !time_in_range(jiffies, pool->last_commit_jiffies,
+			      pool->last_commit_jiffies + COMMIT_PERIOD);
 }
 
 #define thin_pbd(node) rb_entry((node), struct dm_thin_endio_hook, rb_node)