[PATCH net v2 3/4] octeon_ep_vf: Relocate counter updates before NAPI

Vimlesh Kumar posted 4 patches 1 month ago
[PATCH net v2 3/4] octeon_ep_vf: Relocate counter updates before NAPI
Posted by Vimlesh Kumar 1 month ago
Relocate IQ/OQ IN/OUT_CNTS updates to occur before NAPI completion.
Moving the IQ/OQ counter updates before napi_complete_done ensures
1. Counter registers are updated before re-enabling interrupts.
2. Prevents a race where new packets arrive but counters aren't properly
   synchronized.

Fixes: 1cd3b407977c3 ("octeon_ep_vf: add Tx/Rx processing and interrupt support")
Signed-off-by: Sathesh Edara <sedara@marvell.com>
Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Signed-off-by: Vimlesh Kumar <vimleshk@marvell.com>
---
 .../marvell/octeon_ep_vf/octep_vf_main.c        | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
index 420c3f4cf741..e113c846f9d1 100644
--- a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
+++ b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
@@ -286,12 +286,13 @@ static void octep_vf_clean_irqs(struct octep_vf_device *oct)
 }
 
 /**
- * octep_vf_enable_ioq_irq() - Enable MSI-x interrupt of a Tx/Rx queue.
+ * octep_vf_update_pkt() - Update IQ/OQ IN/OUT_CNT registers.
  *
  * @iq: Octeon Tx queue data structure.
  * @oq: Octeon Rx queue data structure.
  */
-static void octep_vf_enable_ioq_irq(struct octep_vf_iq *iq, struct octep_vf_oq *oq)
+
+static void octep_vf_update_pkt(struct octep_vf_iq *iq, struct octep_vf_oq *oq)
 {
 	u32 pkts_pend = oq->pkts_pending;
 
@@ -308,6 +309,17 @@ static void octep_vf_enable_ioq_irq(struct octep_vf_iq *iq, struct octep_vf_oq *
 
 	/* Flush the previous wrties before writing to RESEND bit */
 	smp_wmb();
+}
+
+/**
+ * octep_vf_enable_ioq_irq() - Enable MSI-x interrupt of a Tx/Rx queue.
+ *
+ * @iq: Octeon Tx queue data structure.
+ * @oq: Octeon Rx queue data structure.
+ */
+static void octep_vf_enable_ioq_irq(struct octep_vf_iq *iq,
+				    struct octep_vf_oq *oq)
+{
 	writeq(1UL << OCTEP_VF_OQ_INTR_RESEND_BIT, oq->pkts_sent_reg);
 	writeq(1UL << OCTEP_VF_IQ_INTR_RESEND_BIT, iq->inst_cnt_reg);
 }
@@ -333,6 +345,7 @@ static int octep_vf_napi_poll(struct napi_struct *napi, int budget)
 	if (tx_pending || rx_done >= budget)
 		return budget;
 
+	octep_vf_update_pkt(ioq_vector->iq, ioq_vector->oq);
 	if (likely(napi_complete_done(napi, rx_done)))
 		octep_vf_enable_ioq_irq(ioq_vector->iq, ioq_vector->oq);
 
-- 
2.47.3