blk-throttle: choose a small throtl_slice for SSD

[mirror_ubuntu-bionic-kernel.git] / block / blk-throttle.c

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 93841da808a1b7746c450cec62a978cf9bf8fbce..d00c1c1e99e478099056eb2e592cddece6fe8a1a 100644 (file)
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -18,8 +18,9 @@ static int throtl_grp_quantum = 8;
 /* Total max dispatch from all groups in one round */
 static int throtl_quantum = 32;
 
-/* Throttling is performed over 100ms slice and after that slice is renewed */
-#define DFL_THROTL_SLICE (HZ / 10)
+/* Throttling is performed over a slice and after that slice is renewed */
+#define DFL_THROTL_SLICE_HD (HZ / 10)
+#define DFL_THROTL_SLICE_SSD (HZ / 50)
 #define MAX_THROTL_SLICE (HZ)
 
 static struct blkcg_policy blkcg_policy_throtl;
@@ -1961,7 +1962,6 @@ int blk_throtl_init(struct request_queue *q)
 
        q->td = td;
        td->queue = q;
-       td->throtl_slice = DFL_THROTL_SLICE;
 
        td->limit_valid[LIMIT_MAX] = true;
        td->limit_index = LIMIT_MAX;
@@ -1982,6 +1982,23 @@ void blk_throtl_exit(struct request_queue *q)
        kfree(q->td);
 }
 
+void blk_throtl_register_queue(struct request_queue *q)
+{
+       struct throtl_data *td;
+
+       td = q->td;
+       BUG_ON(!td);
+
+       if (blk_queue_nonrot(q))
+               td->throtl_slice = DFL_THROTL_SLICE_SSD;
+       else
+               td->throtl_slice = DFL_THROTL_SLICE_HD;
+#ifndef CONFIG_BLK_DEV_THROTTLING_LOW
+       /* if no low limit, use previous default */
+       td->throtl_slice = DFL_THROTL_SLICE_HD;
+#endif
+}
+
 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page)
 {