IB/ehca: Refactor sync between completions and destroy_cq using atomic_t

[linux-2.6-omap-h63xx.git] / drivers / infiniband / hw / ehca / ehca_irq.c

diff --git a/drivers/infiniband/hw/ehca/ehca_irq.c b/drivers/infiniband/hw/ehca/ehca_irq.c
index 100329ba33439f79c30c391e17c9e677dbe8c979..3e790a326d97601cef26978f0df2309349b14264 100644 (file)
--- a/drivers/infiniband/hw/ehca/ehca_irq.c
+++ b/drivers/infiniband/hw/ehca/ehca_irq.c
@@ -5,6 +5,8 @@
  *
  *  Authors: Heiko J Schick <schickhj@de.ibm.com>
  *           Khadija Souissi <souissi@de.ibm.com>
+ *           Hoang-Nam Nguyen <hnguyen@de.ibm.com>
+ *           Joachim Fenkes <fenkes@de.ibm.com>
  *
  *  Copyright (c) 2005 IBM Corporation
  *
@@ -212,6 +214,8 @@ static void cq_event_callback(struct ehca_shca *shca,
 
        spin_lock_irqsave(&ehca_cq_idr_lock, flags);
        cq = idr_find(&ehca_cq_idr, token);
+       if (cq)
+               atomic_inc(&cq->nr_events);
        spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
 
        if (!cq)
@@ -219,6 +223,9 @@ static void cq_event_callback(struct ehca_shca *shca,
 
        ehca_error_data(shca, cq, cq->ipz_cq_handle.handle);
 
+       if (atomic_dec_and_test(&cq->nr_events))
+               wake_up(&cq->wait_completion);
+
        return;
 }
 
@@ -414,25 +421,22 @@ static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
                token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
                spin_lock_irqsave(&ehca_cq_idr_lock, flags);
                cq = idr_find(&ehca_cq_idr, token);
+               if (cq)
+                       atomic_inc(&cq->nr_events);
+               spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
                if (cq == NULL) {
-                       spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
                        ehca_err(&shca->ib_device,
                                 "Invalid eqe for non-existing cq token=%x",
                                 token);
                        return;
                }
                reset_eq_pending(cq);
-               cq->nr_events++;
-               spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
                if (ehca_scaling_code)
                        queue_comp_task(cq);
                else {
                        comp_event_callback(cq);
-                       spin_lock_irqsave(&ehca_cq_idr_lock, flags);
-                       cq->nr_events--;
-                       if (!cq->nr_events)
+                       if (atomic_dec_and_test(&cq->nr_events))
                                wake_up(&cq->wait_completion);
-                       spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
                }
        } else {
                ehca_dbg(&shca->ib_device, "Got non completion event");
@@ -478,15 +482,15 @@ void ehca_process_eq(struct ehca_shca *shca, int is_irq)
                        token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
                        spin_lock(&ehca_cq_idr_lock);
                        eqe_cache[eqe_cnt].cq = idr_find(&ehca_cq_idr, token);
+                       if (eqe_cache[eqe_cnt].cq)
+                               atomic_inc(&eqe_cache[eqe_cnt].cq->nr_events);
+                       spin_unlock(&ehca_cq_idr_lock);
                        if (!eqe_cache[eqe_cnt].cq) {
-                               spin_unlock(&ehca_cq_idr_lock);
                                ehca_err(&shca->ib_device,
                                         "Invalid eqe for non-existing cq "
                                         "token=%x", token);
                                continue;
                        }
-                       eqe_cache[eqe_cnt].cq->nr_events++;
-                       spin_unlock(&ehca_cq_idr_lock);
                } else
                        eqe_cache[eqe_cnt].cq = NULL;
                eqe_cnt++;
@@ -517,11 +521,8 @@ void ehca_process_eq(struct ehca_shca *shca, int is_irq)
                        else {
                                struct ehca_cq *cq = eq->eqe_cache[i].cq;
                                comp_event_callback(cq);
-                               spin_lock(&ehca_cq_idr_lock);
-                               cq->nr_events--;
-                               if (!cq->nr_events)
+                               if (atomic_dec_and_test(&cq->nr_events))
                                        wake_up(&cq->wait_completion);
-                               spin_unlock(&ehca_cq_idr_lock);
                        }
                } else {
                        ehca_dbg(&shca->ib_device, "Got non completion event");
@@ -621,13 +622,10 @@ static void run_comp_task(struct ehca_cpu_comp_task* cct)
        while (!list_empty(&cct->cq_list)) {
                cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
                spin_unlock_irqrestore(&cct->task_lock, flags);
-               comp_event_callback(cq);
 
-               spin_lock_irqsave(&ehca_cq_idr_lock, flags);
-               cq->nr_events--;
-               if (!cq->nr_events)
+               comp_event_callback(cq);
+               if (atomic_dec_and_test(&cq->nr_events))
                        wake_up(&cq->wait_completion);
-               spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
 
                spin_lock_irqsave(&cct->task_lock, flags);
                spin_lock(&cq->task_lock);