perf test: Fix bpf test sample mismatch reporting

[linux-2.6-microblaze.git] / block / bfq-iosched.c

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 480e1a1..dd13c2b 100644 (file)
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2662,6 +2662,15 @@ bfq_setup_merge(struct bfq_queue *bfqq, struct bfq_queue *new_bfqq)
         * are likely to increase the throughput.
         */
        bfqq->new_bfqq = new_bfqq;
+       /*
+        * The above assignment schedules the following redirections:
+        * each time some I/O for bfqq arrives, the process that
+        * generated that I/O is disassociated from bfqq and
+        * associated with new_bfqq. Here we increases new_bfqq->ref
+        * in advance, adding the number of processes that are
+        * expected to be associated with new_bfqq as they happen to
+        * issue I/O.
+        */
        new_bfqq->ref += process_refs;
        return new_bfqq;
 }
@@ -2724,6 +2733,10 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 {
        struct bfq_queue *in_service_bfqq, *new_bfqq;
 
+       /* if a merge has already been setup, then proceed with that first */
+       if (bfqq->new_bfqq)
+               return bfqq->new_bfqq;
+
        /*
         * Check delayed stable merge for rotational or non-queueing
         * devs. For this branch to be executed, bfqq must not be
@@ -2825,9 +2838,6 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
        if (bfq_too_late_for_merging(bfqq))
                return NULL;
 
-       if (bfqq->new_bfqq)
-               return bfqq->new_bfqq;
-
        if (!io_struct || unlikely(bfqq == &bfqd->oom_bfqq))
                return NULL;