blk-mq: avoid sysfs buffer overflow with too many CPU cores

[platform/kernel/linux-rpi.git] / block / bfq-iosched.h

diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index a8a2e5a..a41e988 100644 (file)
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -351,6 +351,32 @@ struct bfq_queue {
        unsigned long split_time; /* time of last split */
 
        unsigned long first_IO_time; /* time of first I/O for this queue */
+
+       /* max service rate measured so far */
+       u32 max_service_rate;
+       /*
+        * Ratio between the service received by bfqq while it is in
+        * service, and the cumulative service (of requests of other
+        * queues) that may be injected while bfqq is empty but still
+        * in service. To increase precision, the coefficient is
+        * measured in tenths of unit. Here are some example of (1)
+        * ratios, (2) resulting percentages of service injected
+        * w.r.t. to the total service dispatched while bfqq is in
+        * service, and (3) corresponding values of the coefficient:
+        * 1 (50%) -> 10
+        * 2 (33%) -> 20
+        * 10 (9%) -> 100
+        * 9.9 (9%) -> 99
+        * 1.5 (40%) -> 15
+        * 0.5 (66%) -> 5
+        * 0.1 (90%) -> 1
+        *
+        * So, if the coefficient is lower than 10, then
+        * injected service is more than bfqq service.
+        */
+       unsigned int inject_coeff;
+       /* amount of service injected in current service slot */
+       unsigned int injected_service;
 };
 
 /**
@@ -469,6 +495,9 @@ struct bfq_data {
        /* on-disk position of the last served request */
        sector_t last_position;
 
+       /* position of the last served request for the in-service queue */
+       sector_t in_serv_last_pos;
+
        /* time of last request completion (ns) */
        u64 last_completion;