blkio: Core implementation of throttle policy
o Actual implementation of throttling policy in block layer. Currently it
implements READ and WRITE bytes per second throttling logic. IOPS throttling
comes in later patches.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index ca83a97..10a0c29 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -130,6 +130,8 @@
/* bio only flags */
__REQ_UNPLUG, /* unplug the immediately after submission */
__REQ_RAHEAD, /* read ahead, can fail anytime */
+ __REQ_THROTTLED, /* This bio has already been subjected to
+ * throttling rules. Don't do it again. */
/* request only flags */
__REQ_SORTED, /* elevator knows about this request */
@@ -172,6 +174,7 @@
#define REQ_UNPLUG (1 << __REQ_UNPLUG)
#define REQ_RAHEAD (1 << __REQ_RAHEAD)
+#define REQ_THROTTLED (1 << __REQ_THROTTLED)
#define REQ_SORTED (1 << __REQ_SORTED)
#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 780824e..1341df5 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -371,6 +371,11 @@
#if defined(CONFIG_BLK_DEV_BSG)
struct bsg_class_device bsg_dev;
#endif
+
+#ifdef CONFIG_BLK_DEV_THROTTLING
+ /* Throttle data */
+ struct throtl_data *td;
+#endif
};
#define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */
@@ -1131,6 +1136,7 @@
struct work_struct;
int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
+int kblockd_schedule_delayed_work(struct request_queue *q, struct delayed_work *dwork, unsigned long delay);
#ifdef CONFIG_BLK_CGROUP
/*
@@ -1174,6 +1180,24 @@
}
#endif
+#ifdef CONFIG_BLK_DEV_THROTTLING
+extern int blk_throtl_init(struct request_queue *q);
+extern void blk_throtl_exit(struct request_queue *q);
+extern int blk_throtl_bio(struct request_queue *q, struct bio **bio);
+extern void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay);
+extern void throtl_shutdown_timer_wq(struct request_queue *q);
+#else /* CONFIG_BLK_DEV_THROTTLING */
+static inline int blk_throtl_bio(struct request_queue *q, struct bio **bio)
+{
+ return 0;
+}
+
+static inline int blk_throtl_init(struct request_queue *q) { return 0; }
+static inline int blk_throtl_exit(struct request_queue *q) { return 0; }
+static inline void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay) {}
+static inline void throtl_shutdown_timer_wq(struct request_queue *q) {}
+#endif /* CONFIG_BLK_DEV_THROTTLING */
+
#define MODULE_ALIAS_BLOCKDEV(major,minor) \
MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \