[RFC] ratelimit: fix time interval by setting right start time

[Jaewon Kim <jaewon31.kim@gmail.com>]

rs->begin should be initialized to the current jiffies if the begin was 0.
Even when the time interval passes, the current resetting logic sets the begin
back to 0. So next interval starts from the next call rather than from the
current resetting call. This incurrs improper suppression.

For example:
B will be suppressed althouth 3 seconds passed.
	DEFINE_RATELIMIT_STATE(limit, HZ, 1);
	__ratelimit(&limit); /* A */
	sleep(3);
	__ratelimit(&limit); /* B */

Signed-off-by: Jaewon Kim <jaewon31.kim@gmail.com>
---
 lib/ratelimit.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 40e03ea..2c5de86 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -49,7 +49,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
 		if (rs->missed)
 			printk(KERN_WARNING "%s: %d callbacks suppressed\n",
 				func, rs->missed);
-		rs->begin   = 0;
+		rs->begin   = jiffies;
 		rs->printed = 0;
 		rs->missed  = 0;
 	}
-- 
1.9.1