From f2919e92d213feaad4b34ea7133bee6a8d27aed1 Mon Sep 17 00:00:00 2001
From: Vivek Goyal <vgoyal@redhat.com>
Date: Fri, 1 Oct 2010 21:16:42 +0200
Subject: [PATCH] --- yaml --- r: 213067 b: refs/heads/master c:
 c49c06e4960949a9bced708858433fcf6ca36a9c h: refs/heads/master i:   213065:
 2e1f3c8dca9fdb0d69c4c0bbdd5dda1d3785ea27   213063:
 e66dc18835141b672f0355e00b1504c89ff0cc96 v: v3

---
 [refs]                     |  2 +-
 trunk/block/blk-throttle.c | 16 +++++++++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index cf28bdc36a48..8c1d1aaeab87 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9355aede5a3c4975e0ba8bbfe2b9d1fd73308916
+refs/heads/master: c49c06e4960949a9bced708858433fcf6ca36a9c
diff --git a/trunk/block/blk-throttle.c b/trunk/block/blk-throttle.c
index c1bc1b6c887a..56ad4531b412 100644
--- a/trunk/block/blk-throttle.c
+++ b/trunk/block/blk-throttle.c
@@ -430,6 +430,7 @@ static bool tg_with_in_iops_limit(struct throtl_data *td, struct throtl_grp *tg,
 	bool rw = bio_data_dir(bio);
 	unsigned int io_allowed;
 	unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd;
+	u64 tmp;
 
 	jiffy_elapsed = jiffy_elapsed_rnd = jiffies - tg->slice_start[rw];
 
@@ -439,7 +440,20 @@ static bool tg_with_in_iops_limit(struct throtl_data *td, struct throtl_grp *tg,
 
 	jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, throtl_slice);
 
-	io_allowed = (tg->iops[rw] * jiffy_elapsed_rnd) / HZ;
+	/*
+	 * jiffy_elapsed_rnd should not be a big value as minimum iops can be
+	 * 1 then at max jiffy elapsed should be equivalent of 1 second as we
+	 * will allow dispatch after 1 second and after that slice should
+	 * have been trimmed.
+	 */
+
+	tmp = (u64)tg->iops[rw] * jiffy_elapsed_rnd;
+	do_div(tmp, HZ);
+
+	if (tmp > UINT_MAX)
+		io_allowed = UINT_MAX;
+	else
+		io_allowed = tmp;
 
 	if (tg->io_disp[rw] + 1 <= io_allowed) {
 		if (wait)