5 files changed, 29 insertions, 39 deletions

diff --git a/drivers/infiniband/hw/ehca/ehca_classes.h b/drivers/infiniband/hw/ehca/ehca_classes.h
index 3550047c1375..8580f2a0ea57 100644
--- a/drivers/infiniband/hw/ehca/ehca_classes.h
+++ b/drivers/infiniband/hw/ehca/ehca_classes.h
@@ -174,8 +174,8 @@ struct ehca_cq {
         spinlock_t cb_lock;
         struct hlist_head qp_hashtab[QP_HASHTAB_LEN];
         struct list_head entry;
-        u32 nr_callbacks; /* #events assigned to cpu by scaling code */
-        u32 nr_events;    /* #events seen */
+        u32 nr_callbacks;   /* #events assigned to cpu by scaling code */
+        atomic_t nr_events; /* #events seen */
         wait_queue_head_t wait_completion;
         spinlock_t task_lock;
         u32 ownpid;
diff --git a/drivers/infiniband/hw/ehca/ehca_cq.c b/drivers/infiniband/hw/ehca/ehca_cq.c
index 94bad273b34c..3729997457ca 100644
--- a/drivers/infiniband/hw/ehca/ehca_cq.c
+++ b/drivers/infiniband/hw/ehca/ehca_cq.c
@@ -146,6 +146,7 @@ struct ib_cq *ehca_create_cq(struct ib_device *device, int cqe, int comp_vector,
         spin_lock_init(&my_cq->spinlock);
         spin_lock_init(&my_cq->cb_lock);
         spin_lock_init(&my_cq->task_lock);
+        atomic_set(&my_cq->nr_events, 0);
         init_waitqueue_head(&my_cq->wait_completion);
         my_cq->ownpid = current->tgid;
 
@@ -303,16 +304,6 @@ create_cq_exit1:
         return cq;
 }
 
-static int get_cq_nr_events(struct ehca_cq *my_cq)
-{
-        int ret;
-        unsigned long flags;
-        spin_lock_irqsave(&ehca_cq_idr_lock, flags);
-        ret = my_cq->nr_events;
-        spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
-        return ret;
-}
-
 int ehca_destroy_cq(struct ib_cq *cq)
 {
         u64 h_ret;
@@ -339,17 +330,18 @@ int ehca_destroy_cq(struct ib_cq *cq)
                 }
         }
 
+        /*
+         * remove the CQ from the idr first to make sure
+         * no more interrupt tasklets will touch this CQ
+         */
         spin_lock_irqsave(&ehca_cq_idr_lock, flags);
-        while (my_cq->nr_events) {
-                spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
-                wait_event(my_cq->wait_completion, !get_cq_nr_events(my_cq));
-                spin_lock_irqsave(&ehca_cq_idr_lock, flags);
-                /* recheck nr_events to assure no cqe has just arrived */
-        }
-
         idr_remove(&ehca_cq_idr, my_cq->token);
         spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
 
+        /* now wait until all pending events have completed */
+        wait_event(my_cq->wait_completion, !atomic_read(&my_cq->nr_events));
+
+        /* nobody's using our CQ any longer -- we can destroy it */
         h_ret = hipz_h_destroy_cq(adapter_handle, my_cq, 0);
         if (h_ret == H_R_STATE) {
                 /* cq in err: read err data and destroy it forcibly */
diff --git a/drivers/infiniband/hw/ehca/ehca_irq.c b/drivers/infiniband/hw/ehca/ehca_irq.c
index 100329ba3343..3e790a326d97 100644
--- 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);
diff --git a/drivers/infiniband/hw/ehca/ehca_irq.h b/drivers/infiniband/hw/ehca/ehca_irq.h
index 6ed06ee033ed..3346cb06cea6 100644
--- a/drivers/infiniband/hw/ehca/ehca_irq.h
+++ b/drivers/infiniband/hw/ehca/ehca_irq.h
@@ -47,7 +47,6 @@ struct ehca_shca;
 
 #include <linux/interrupt.h>
 #include <linux/types.h>
-#include <asm/atomic.h>
 
 int ehca_error_data(struct ehca_shca *shca, void *data, u64 resource);
 
diff --git a/drivers/infiniband/hw/ehca/ehca_tools.h b/drivers/infiniband/hw/ehca/ehca_tools.h
index 973c4b591545..03b185f873da 100644
--- a/drivers/infiniband/hw/ehca/ehca_tools.h
+++ b/drivers/infiniband/hw/ehca/ehca_tools.h
@@ -59,6 +59,7 @@
 #include <linux/cpu.h>
 #include <linux/device.h>
 
+#include <asm/atomic.h>
 #include <asm/abs_addr.h>
 #include <asm/ibmebus.h>
 #include <asm/io.h>