2 files changed, 16 insertions, 1 deletions

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 006dcf7e808a..3f36d37ac5ba 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -232,6 +232,7 @@ enum {
         WQ_NON_REENTRANT        = 1 << 2, /* guarantee non-reentrance */
         WQ_RESCUER              = 1 << 3, /* has an rescue worker */
         WQ_HIGHPRI              = 1 << 4, /* high priority */
+        WQ_CPU_INTENSIVE        = 1 << 5, /* cpu instensive workqueue */
 
         WQ_MAX_ACTIVE           = 512,    /* I like 512, better ideas? */
         WQ_DFL_ACTIVE           = WQ_MAX_ACTIVE / 2,
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5775717288d5..6fa847c5c5e9 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -52,8 +52,10 @@ enum {
         WORKER_PREP             = 1 << 3,       /* preparing to run works */
         WORKER_ROGUE            = 1 << 4,       /* not bound to any cpu */
         WORKER_REBIND           = 1 << 5,       /* mom is home, come back */
+        WORKER_CPU_INTENSIVE    = 1 << 6,       /* cpu intensive */
 
-        WORKER_NOT_RUNNING      = WORKER_PREP | WORKER_ROGUE | WORKER_REBIND,
+        WORKER_NOT_RUNNING      = WORKER_PREP | WORKER_ROGUE | WORKER_REBIND |
+                                  WORKER_CPU_INTENSIVE,
 
         /* gcwq->trustee_state */
         TRUSTEE_START           = 0,            /* start */
@@ -1641,6 +1643,7 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
         struct cpu_workqueue_struct *cwq = get_work_cwq(work);
         struct global_cwq *gcwq = cwq->gcwq;
         struct hlist_head *bwh = busy_worker_head(gcwq, work);
+        bool cpu_intensive = cwq->wq->flags & WQ_CPU_INTENSIVE;
         work_func_t f = work->func;
         int work_color;
         struct worker *collision;
@@ -1692,6 +1695,13 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
                         gcwq->flags &= ~GCWQ_HIGHPRI_PENDING;
         }
 
+        /*
+         * CPU intensive works don't participate in concurrency
+         * management.  They're the scheduler's responsibility.
+         */
+        if (unlikely(cpu_intensive))
+                worker_set_flags(worker, WORKER_CPU_INTENSIVE, true);
+
         spin_unlock_irq(&gcwq->lock);
 
         work_clear_pending(work);
@@ -1713,6 +1723,10 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
 
         spin_lock_irq(&gcwq->lock);
 
+        /* clear cpu intensive status */
+        if (unlikely(cpu_intensive))
+                worker_clr_flags(worker, WORKER_CPU_INTENSIVE);
+
         /* we're done with it, release */
         hlist_del_init(&worker->hentry);
         worker->current_work = NULL;