blk-throttle: fix io hung due to configuration updates

[linux-block.git] / block / blk-throttle.h

diff --git a/block/blk-throttle.h b/block/blk-throttle.h
index ee7299e6dea911a0568a99d802947886bdede3c4..66b4292b1b92a6976e41e768edf2728c3f3ccfc6 100644 (file)
--- a/block/blk-throttle.h
+++ b/block/blk-throttle.h
@@ -121,6 +121,15 @@ struct throtl_grp {
        uint64_t last_bytes_disp[2];
        unsigned int last_io_disp[2];
 
+       /*
+        * The following two fields are updated when new configuration is
+        * submitted while some bios are still throttled, they record how many
+        * bytes/ios are waited already in previous configuration, and they will
+        * be used to calculate wait time under new configuration.
+        */
+       uint64_t carryover_bytes[2];
+       unsigned int carryover_ios[2];
+
        unsigned long last_check_time;
 
        unsigned long latency_target; /* us */