IB/ehca: Rework irq handler
Rework ehca interrupt handling to avoid/reduce missed irq events.
Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ehca/ehca_irq.c b/drivers/infiniband/hw/ehca/ehca_irq.c
index 6c4f9f9..b923b5d 100644
--- a/drivers/infiniband/hw/ehca/ehca_irq.c
+++ b/drivers/infiniband/hw/ehca/ehca_irq.c
@@ -206,7 +206,7 @@
}
static void cq_event_callback(struct ehca_shca *shca,
- u64 eqe)
+ u64 eqe)
{
struct ehca_cq *cq;
unsigned long flags;
@@ -318,7 +318,7 @@
"disruptive port %x configuration change", port);
ehca_info(&shca->ib_device,
- "port %x is inactive.", port);
+ "port %x is inactive.", port);
event.device = &shca->ib_device;
event.event = IB_EVENT_PORT_ERR;
event.element.port_num = port;
@@ -326,7 +326,7 @@
ib_dispatch_event(&event);
ehca_info(&shca->ib_device,
- "port %x is active.", port);
+ "port %x is active.", port);
event.device = &shca->ib_device;
event.event = IB_EVENT_PORT_ACTIVE;
event.element.port_num = port;
@@ -401,87 +401,143 @@
return IRQ_HANDLED;
}
+
+static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
+{
+ u64 eqe_value;
+ u32 token;
+ unsigned long flags;
+ struct ehca_cq *cq;
+ eqe_value = eqe->entry;
+ ehca_dbg(&shca->ib_device, "eqe_value=%lx", eqe_value);
+ if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
+ ehca_dbg(&shca->ib_device, "... completion event");
+ 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 == 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);
+#ifdef CONFIG_INFINIBAND_EHCA_SCALING
+ queue_comp_task(cq);
+ spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
+#else
+ spin_unlock_irqrestore(&ehca_cq_idr_lock, flags);
+ comp_event_callback(cq);
+#endif
+ } else {
+ ehca_dbg(&shca->ib_device,
+ "Got non completion event");
+ parse_identifier(shca, eqe_value);
+ }
+}
+
+void ehca_process_eq(struct ehca_shca *shca, int is_irq)
+{
+ struct ehca_eq *eq = &shca->eq;
+ struct ehca_eqe_cache_entry *eqe_cache = eq->eqe_cache;
+ u64 eqe_value;
+ unsigned long flags;
+ int eqe_cnt, i;
+ int eq_empty = 0;
+
+ spin_lock_irqsave(&eq->irq_spinlock, flags);
+ if (is_irq) {
+ const int max_query_cnt = 100;
+ int query_cnt = 0;
+ int int_state = 1;
+ do {
+ int_state = hipz_h_query_int_state(
+ shca->ipz_hca_handle, eq->ist);
+ query_cnt++;
+ iosync();
+ } while (int_state && query_cnt < max_query_cnt);
+ if (unlikely((query_cnt == max_query_cnt)))
+ ehca_dbg(&shca->ib_device, "int_state=%x query_cnt=%x",
+ int_state, query_cnt);
+ }
+
+ /* read out all eqes */
+ eqe_cnt = 0;
+ do {
+ u32 token;
+ eqe_cache[eqe_cnt].eqe =
+ (struct ehca_eqe *)ehca_poll_eq(shca, eq);
+ if (!eqe_cache[eqe_cnt].eqe)
+ break;
+ eqe_value = eqe_cache[eqe_cnt].eqe->entry;
+ if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
+ 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) {
+ spin_unlock(&ehca_cq_idr_lock);
+ ehca_err(&shca->ib_device,
+ "Invalid eqe for non-existing cq "
+ "token=%x", token);
+ continue;
+ }
+ spin_unlock(&ehca_cq_idr_lock);
+ } else
+ eqe_cache[eqe_cnt].cq = NULL;
+ eqe_cnt++;
+ } while (eqe_cnt < EHCA_EQE_CACHE_SIZE);
+ if (!eqe_cnt) {
+ if (is_irq)
+ ehca_dbg(&shca->ib_device,
+ "No eqe found for irq event");
+ goto unlock_irq_spinlock;
+ } else if (!is_irq)
+ ehca_dbg(&shca->ib_device, "deadman found %x eqe", eqe_cnt);
+ if (unlikely(eqe_cnt == EHCA_EQE_CACHE_SIZE))
+ ehca_dbg(&shca->ib_device, "too many eqes for one irq event");
+ /* enable irq for new packets */
+ for (i = 0; i < eqe_cnt; i++) {
+ if (eq->eqe_cache[i].cq)
+ reset_eq_pending(eq->eqe_cache[i].cq);
+ }
+ /* check eq */
+ spin_lock(&eq->spinlock);
+ eq_empty = (!ipz_eqit_eq_peek_valid(&shca->eq.ipz_queue));
+ spin_unlock(&eq->spinlock);
+ /* call completion handler for cached eqes */
+ for (i = 0; i < eqe_cnt; i++)
+ if (eq->eqe_cache[i].cq) {
+#ifdef CONFIG_INFINIBAND_EHCA_SCALING
+ spin_lock(&ehca_cq_idr_lock);
+ queue_comp_task(eq->eqe_cache[i].cq);
+ spin_unlock(&ehca_cq_idr_lock);
+#else
+ comp_event_callback(eq->eqe_cache[i].cq);
+#endif
+ } else {
+ ehca_dbg(&shca->ib_device, "Got non completion event");
+ parse_identifier(shca, eq->eqe_cache[i].eqe->entry);
+ }
+ /* poll eq if not empty */
+ if (eq_empty)
+ goto unlock_irq_spinlock;
+ do {
+ struct ehca_eqe *eqe;
+ eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->eq);
+ if (!eqe)
+ break;
+ process_eqe(shca, eqe);
+ eqe_cnt++;
+ } while (1);
+
+unlock_irq_spinlock:
+ spin_unlock_irqrestore(&eq->irq_spinlock, flags);
+}
+
void ehca_tasklet_eq(unsigned long data)
{
- struct ehca_shca *shca = (struct ehca_shca*)data;
- struct ehca_eqe *eqe;
- int int_state;
- int query_cnt = 0;
-
- do {
- eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->eq);
-
- if ((shca->hw_level >= 2) && eqe)
- int_state = 1;
- else
- int_state = 0;
-
- while ((int_state == 1) || eqe) {
- while (eqe) {
- u64 eqe_value = eqe->entry;
-
- ehca_dbg(&shca->ib_device,
- "eqe_value=%lx", eqe_value);
-
- /* TODO: better structure */
- if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT,
- eqe_value)) {
- unsigned long flags;
- u32 token;
- struct ehca_cq *cq;
-
- ehca_dbg(&shca->ib_device,
- "... completion event");
- 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 == NULL) {
- spin_unlock_irqrestore(&ehca_cq_idr_lock,
- flags);
- break;
- }
-
- reset_eq_pending(cq);
-#ifdef CONFIG_INFINIBAND_EHCA_SCALING
- queue_comp_task(cq);
- spin_unlock_irqrestore(&ehca_cq_idr_lock,
- flags);
-#else
- spin_unlock_irqrestore(&ehca_cq_idr_lock,
- flags);
- comp_event_callback(cq);
-#endif
- } else {
- ehca_dbg(&shca->ib_device,
- "... non completion event");
- parse_identifier(shca, eqe_value);
- }
- eqe =
- (struct ehca_eqe *)ehca_poll_eq(shca,
- &shca->eq);
- }
-
- if (shca->hw_level >= 2) {
- int_state =
- hipz_h_query_int_state(shca->ipz_hca_handle,
- shca->eq.ist);
- query_cnt++;
- iosync();
- if (query_cnt >= 100) {
- query_cnt = 0;
- int_state = 0;
- }
- }
- eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->eq);
-
- }
- } while (int_state != 0);
-
- return;
+ ehca_process_eq((struct ehca_shca*)data, 1);
}
#ifdef CONFIG_INFINIBAND_EHCA_SCALING
@@ -654,11 +710,11 @@
list_splice_init(&cct->cq_list, &list);
while(!list_empty(&list)) {
- cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
+ cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
- list_del(&cq->entry);
- __queue_comp_task(cq, per_cpu_ptr(pool->cpu_comp_tasks,
- smp_processor_id()));
+ list_del(&cq->entry);
+ __queue_comp_task(cq, per_cpu_ptr(pool->cpu_comp_tasks,
+ smp_processor_id()));
}
spin_unlock_irqrestore(&cct->task_lock, flags_cct);