blk-mq: introduce blk_mq_hw_queue_first_cpu() to figure out first cpu

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

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 022a0de7319b97806c23544f47363e61ae28c4a9..3362f274d0861dfaf7e68013c6461f5e818c5db8 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1248,6 +1248,15 @@ static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx)
        }
 }
 
+static inline int blk_mq_first_mapped_cpu(struct blk_mq_hw_ctx *hctx)
+{
+       int cpu = cpumask_first_and(hctx->cpumask, cpu_online_mask);
+
+       if (cpu >= nr_cpu_ids)
+               cpu = cpumask_first(hctx->cpumask);
+       return cpu;
+}
+
 /*
  * It'd be great if the workqueue API had a way to pass
  * in a mask and had some smarts for more clever placement.
@@ -1267,14 +1276,7 @@ select_cpu:
                next_cpu = cpumask_next_and(next_cpu, hctx->cpumask,
                                cpu_online_mask);
                if (next_cpu >= nr_cpu_ids)
-                       next_cpu = cpumask_first_and(hctx->cpumask, cpu_online_mask);
-
-               /*
-                * No online CPU is found, so have to make sure hctx->next_cpu
-                * is set correctly for not breaking workqueue.
-                */
-               if (next_cpu >= nr_cpu_ids)
-                       next_cpu = cpumask_first(hctx->cpumask);
+                       next_cpu = blk_mq_first_mapped_cpu(hctx);
                hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH;
        }
 
@@ -2278,10 +2280,7 @@ static void blk_mq_map_swqueue(struct request_queue *q)
                /*
                 * Initialize batch roundrobin counts
                 */
-               hctx->next_cpu = cpumask_first_and(hctx->cpumask,
-                               cpu_online_mask);
-               if (hctx->next_cpu >= nr_cpu_ids)
-                       hctx->next_cpu = cpumask_first(hctx->cpumask);
+               hctx->next_cpu = blk_mq_first_mapped_cpu(hctx);
                hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH;
        }
 }