From: Devesh Sharma <[email protected]>
Stale entries in the CQ being destroyed causes hardware to generate EQEs
indefinetly for a given CQ.
Thus causing uncontrolled execution of irq_handler. This patch fixes this using
following sementics:
* irq_handler will ring EQ doorbell atleast once and implement budgeting
scheme.
* cq_destroy will count number of valid entires during destroy and ring
cq-db so that hadrware does not generate uncontrolled EQE.
* cq_destroy will synchronize with last running irq_handler instance.
---
drivers/infiniband/hw/ocrdma/ocrdma.h | 15 ++++-
drivers/infiniband/hw/ocrdma/ocrdma_hw.c | 58 ++++++++++---------
drivers/infiniband/hw/ocrdma/ocrdma_verbs.c | 80 +++++++++++++++++++++++----
3 files changed, 111 insertions(+), 42 deletions(-)
diff --git a/drivers/infiniband/hw/ocrdma/ocrdma.h
b/drivers/infiniband/hw/ocrdma/ocrdma.h
index adc11d1..5747fde 100644
--- a/drivers/infiniband/hw/ocrdma/ocrdma.h
+++ b/drivers/infiniband/hw/ocrdma/ocrdma.h
@@ -183,8 +183,7 @@ struct ocrdma_cq {
*/
u32 max_hw_cqe;
bool phase_change;
- bool armed, solicited;
- bool arm_needed;
+ bool deferred_arm, deferred_sol;
spinlock_t cq_lock ____cacheline_aligned; /* provide synchronization
* to cq polling
@@ -197,6 +196,7 @@ struct ocrdma_cq {
struct ocrdma_ucontext *ucontext;
dma_addr_t pa;
u32 len;
+ u32 cqe_cnt;
/* head of all qp's sq and rq for which cqes need to be flushed
* by the software.
@@ -422,5 +422,16 @@ static inline int is_cqe_wr_imm(struct ocrdma_cqe *cqe)
OCRDMA_CQE_WRITE_IMM) ? 1 : 0;
}
+static inline int ocrdma_get_eq_table_index(struct ocrdma_dev *dev, int eqid)
+{
+ int indx;
+
+ for (indx = 0; indx < dev->eq_cnt; indx++) {
+ if (dev->eq_tbl[indx].q.id == eqid)
+ return indx;
+ }
+ return -EINVAL;
+}
+int ocrdma_get_irq(struct ocrdma_dev *dev, struct ocrdma_eq *eq);
#endif
diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_hw.c
b/drivers/infiniband/hw/ocrdma/ocrdma_hw.c
index 50219ab..9490b41 100644
--- a/drivers/infiniband/hw/ocrdma/ocrdma_hw.c
+++ b/drivers/infiniband/hw/ocrdma/ocrdma_hw.c
@@ -444,7 +444,7 @@ mbx_err:
return status;
}
-static int ocrdma_get_irq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
+int ocrdma_get_irq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
{
int irq;
@@ -526,6 +526,7 @@ static u32 ocrdma_encoded_q_len(int q_len)
return len_encoded;
}
+
static int ocrdma_mbx_create_mq(struct ocrdma_dev *dev,
struct ocrdma_queue_info *mq,
struct ocrdma_queue_info *cq)
@@ -574,6 +575,7 @@ static int ocrdma_create_mq(struct ocrdma_dev *dev)
if (status)
goto alloc_err;
+ dev->eq_tbl[0].cq_cnt++;
status = ocrdma_mbx_mq_cq_create(dev, &dev->mq.cq, &dev->eq_tbl[0].q);
if (status)
goto mbx_cq_free;
@@ -858,16 +860,8 @@ static void ocrdma_qp_cq_handler(struct ocrdma_dev *dev,
u16 cq_idx)
BUG();
cq = dev->cq_tbl[cq_idx];
- if (cq == NULL) {
- pr_err("%s%d invalid id=0x%x\n", __func__, dev->id, cq_idx);
+ if (cq == NULL)
return;
- }
- spin_lock_irqsave(&cq->cq_lock, flags);
- cq->armed = false;
- cq->solicited = false;
- spin_unlock_irqrestore(&cq->cq_lock, flags);
-
- ocrdma_ring_cq_db(dev, cq->id, false, false, 0);
if (cq->ibcq.comp_handler) {
spin_lock_irqsave(&cq->comp_handler_lock, flags);
@@ -892,27 +886,35 @@ static irqreturn_t ocrdma_irq_handler(int irq, void
*handle)
struct ocrdma_dev *dev = eq->dev;
struct ocrdma_eqe eqe;
struct ocrdma_eqe *ptr;
- u16 eqe_popped = 0;
u16 cq_id;
- while (1) {
+ int budget = eq->cq_cnt;
+
+ do {
ptr = ocrdma_get_eqe(eq);
eqe = *ptr;
ocrdma_le32_to_cpu(&eqe, sizeof(eqe));
if ((eqe.id_valid & OCRDMA_EQE_VALID_MASK) == 0)
break;
- eqe_popped += 1;
+
ptr->id_valid = 0;
+ /* ring eq doorbell as soon as its consumed. */
+ ocrdma_ring_eq_db(dev, eq->q.id, false, true, 1);
/* check whether its CQE or not. */
if ((eqe.id_valid & OCRDMA_EQE_FOR_CQE_MASK) == 0) {
cq_id = eqe.id_valid >> OCRDMA_EQE_RESOURCE_ID_SHIFT;
ocrdma_cq_handler(dev, cq_id);
}
ocrdma_eq_inc_tail(eq);
- }
- ocrdma_ring_eq_db(dev, eq->q.id, true, true, eqe_popped);
- /* Ring EQ doorbell with num_popped to 0 to enable interrupts again. */
- if (dev->nic_info.intr_mode == BE_INTERRUPT_MODE_INTX)
- ocrdma_ring_eq_db(dev, eq->q.id, true, true, 0);
+
+ /* There can be a stale EQE after the last bound CQ is
+ * destroyed. EQE valid and budget == 0 implies this.
+ */
+ if (budget)
+ budget--;
+
+ } while (budget);
+
+ ocrdma_ring_eq_db(dev, eq->q.id, true, true, 0);
return IRQ_HANDLED;
}
@@ -1357,12 +1359,12 @@ static void ocrdma_unbind_eq(struct ocrdma_dev *dev,
u16 eq_id)
int i;
mutex_lock(&dev->dev_lock);
- for (i = 0; i < dev->eq_cnt; i++) {
- if (dev->eq_tbl[i].q.id != eq_id)
- continue;
- dev->eq_tbl[i].cq_cnt -= 1;
- break;
- }
+
+ i = ocrdma_get_eq_table_index(dev, eq_id);
+ if (i == -EINVAL)
+ BUG();
+ dev->eq_tbl[i].cq_cnt -= 1;
+
mutex_unlock(&dev->dev_lock);
}
@@ -1417,6 +1419,8 @@ int ocrdma_mbx_create_cq(struct ocrdma_dev *dev, struct
ocrdma_cq *cq,
cq->eqn = ocrdma_bind_eq(dev);
cmd->cmd.req.rsvd_version = OCRDMA_CREATE_CQ_VER3;
cqe_count = cq->len / cqe_size;
+ cq->cqe_cnt = cqe_count;
+
if (cqe_count > 1024) {
/* Set cnt to 3 to indicate more than 1024 cq entries */
cmd->cmd.ev_cnt_flags |= (0x3 << OCRDMA_CREATE_CQ_CNT_SHIFT);
@@ -1484,12 +1488,10 @@ int ocrdma_mbx_destroy_cq(struct ocrdma_dev *dev,
struct ocrdma_cq *cq)
(cq->id << OCRDMA_DESTROY_CQ_QID_SHIFT) &
OCRDMA_DESTROY_CQ_QID_MASK;
- ocrdma_unbind_eq(dev, cq->eqn);
status = ocrdma_mbx_cmd(dev, (struct ocrdma_mqe *)cmd);
- if (status)
- goto mbx_err;
+ ocrdma_unbind_eq(dev, cq->eqn);
dma_free_coherent(&dev->nic_info.pdev->dev, cq->len, cq->va, cq->pa);
-mbx_err:
+
kfree(cmd);
return status;
}
diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
index 69f1d12..e07b8c5 100644
--- a/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
+++ b/drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
@@ -927,9 +927,7 @@ struct ib_cq *ocrdma_create_cq(struct ib_device *ibdev, int
entries, int vector,
goto ctx_err;
}
cq->phase = OCRDMA_CQE_VALID;
- cq->arm_needed = true;
dev->cq_tbl[cq->id] = cq;
-
return &cq->ibcq;
ctx_err:
@@ -952,13 +950,53 @@ int ocrdma_resize_cq(struct ib_cq *ibcq, int new_cnt,
return status;
}
+void ocrdma_flush_cq(struct ocrdma_cq *cq)
+{
+ int cqe_cnt;
+ int valid_count = 0;
+ unsigned long flags;
+
+ struct ocrdma_dev *dev = get_ocrdma_dev(cq->ibcq.device);
+ struct ocrdma_cqe *cqe = NULL;
+
+ cqe = cq->va;
+ cqe_cnt = cq->cqe_cnt;
+
+ /* Last irq might have scheduled a polling thread
+ * sync-up with it before hard flushing.
+ */
+ spin_lock_irqsave(&cq->cq_lock, flags);
+ while (cqe_cnt) {
+ if (is_cqe_valid(cq, cqe))
+ valid_count++;
+ cqe++;
+ cqe_cnt--;
+ }
+ ocrdma_ring_cq_db(dev, cq->id, false, false, valid_count);
+ spin_unlock_irqrestore(&cq->cq_lock, flags);
+}
+
int ocrdma_destroy_cq(struct ib_cq *ibcq)
{
int status;
struct ocrdma_cq *cq = get_ocrdma_cq(ibcq);
+ struct ocrdma_eq *eq = NULL;
struct ocrdma_dev *dev = get_ocrdma_dev(ibcq->device);
int pdid = 0;
+ u32 irq, indx;
+ dev->cq_tbl[cq->id] = NULL;
+
+ indx = ocrdma_get_eq_table_index(dev, cq->eqn);
+
+ if (indx == -EINVAL)
+ BUG();
+ eq = &dev->eq_tbl[indx];
+
+ irq = ocrdma_get_irq(dev, eq);
+ synchronize_irq(irq);
+
+ ocrdma_flush_cq(cq);
status = ocrdma_mbx_destroy_cq(dev, cq);
if (cq->ucontext) {
@@ -969,7 +1007,6 @@ int ocrdma_destroy_cq(struct ib_cq *ibcq)
ocrdma_get_db_addr(dev, pdid),
dev->nic_info.db_page_size);
}
- dev->cq_tbl[cq->id] = NULL;
kfree(cq);
return status;
@@ -2706,10 +2743,17 @@ expand_cqe:
}
stop_cqe:
cq->getp = cur_getp;
- if (polled_hw_cqes || expand || stop) {
- ocrdma_ring_cq_db(dev, cq->id, cq->armed, cq->solicited,
+ if (polled_hw_cqes && cq->deferred_arm) {
+ ocrdma_ring_cq_db(dev, cq->id, true, cq->deferred_sol,
+ polled_hw_cqes);
+ cq->deferred_arm = false;
+ cq->deferred_sol = false;
+ } else if (polled_hw_cqes) {
+ /* We need to pop the CQE. No need to arm */
+ ocrdma_ring_cq_db(dev, cq->id, false, false,
polled_hw_cqes);
}
+
return i;
}
@@ -2784,25 +2828,37 @@ int ocrdma_arm_cq(struct ib_cq *ibcq, enum
ib_cq_notify_flags cq_flags)
u16 cur_getp;
struct ocrdma_cqe *cqe;
unsigned long flags;
+ bool arm_needed = false, sol_needed = false;
cq_id = cq->id;
spin_lock_irqsave(&cq->cq_lock, flags);
if (cq_flags & IB_CQ_NEXT_COMP || cq_flags & IB_CQ_SOLICITED)
- cq->armed = true;
+ arm_needed = true;
if (cq_flags & IB_CQ_SOLICITED)
- cq->solicited = true;
+ sol_needed = true;
cur_getp = cq->getp;
cqe = cq->va + cur_getp;
/* check whether any valid cqe exist or not, if not then safe to
- * arm. If cqe is not yet consumed, then let it get consumed and then
- * we arm it to avoid false interrupts.
+ * arm. If cqe is not yet consumed, then we defer arming until first
+ * CQE is polled from CQ.
*/
- if (!is_cqe_valid(cq, cqe) || cq->arm_needed) {
- cq->arm_needed = false;
- ocrdma_ring_cq_db(dev, cq_id, cq->armed, cq->solicited, 0);
+ if (!is_cqe_valid(cq, cqe)) {
+ ocrdma_ring_cq_db(dev, cq_id, arm_needed, sol_needed, 0);
+ } else {
+ if (!arm_needed) {
+ /* Arming not required. Just notify the CQ
+ * for solicit requested.
+ */
+ ocrdma_ring_cq_db(dev, cq_id, false, sol_needed, 0);
+ cq->deferred_sol = false;
+ cq->deferred_arm = false;
+ } else {
+ cq->deferred_arm = arm_needed;
+ cq->deferred_sol = sol_needed;
+ }
}
spin_unlock_irqrestore(&cq->cq_lock, flags);
return 0;
--
1.7.1
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