Utilize READ_ONCE and WRITE_ONCE APIs for IO queue Tx/Rx variable access to prevent compiler optimization and reordering. Additionally, ensure IO queue OUT/IN_CNT registers are flushed by performing a read-back after writing. Relocate IQ/OQ IN/OUT_CNTS updates to occur before NAPI completion, and replace napi_complete with napi_complete_done. Fixes: 37d79d0596062 ("octeon_ep: add Tx/Rx processing and interrupt support") Signed-off-by: Sathesh Edara Signed-off-by: Shinas Rasheed Signed-off-by: Vimlesh Kumar --- .../ethernet/marvell/octeon_ep/octep_main.c | 40 +++++++++++++------ .../net/ethernet/marvell/octeon_ep/octep_rx.c | 27 +++++++++---- 2 files changed, 47 insertions(+), 20 deletions(-) diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c index bcea3fc26a8c..ccfb248d0914 100644 --- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c +++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c @@ -555,28 +555,43 @@ static void octep_clean_irqs(struct octep_device *oct) } /** - * octep_enable_ioq_irq() - Enable MSI-x interrupt of a Tx/Rx queue. + * octep_update_pkt() - Update IQ/OQ IN/OUT_CNT registers. * * @iq: Octeon Tx queue data structure. * @oq: Octeon Rx queue data structure. */ -static void octep_enable_ioq_irq(struct octep_iq *iq, struct octep_oq *oq) +static void octep_update_pkt(struct octep_iq *iq, struct octep_oq *oq) { - u32 pkts_pend = oq->pkts_pending; + u32 pkts_pend = READ_ONCE(oq->pkts_pending); + u32 last_pkt_count = READ_ONCE(oq->last_pkt_count); + u32 pkts_processed = READ_ONCE(iq->pkts_processed); + u32 pkt_in_done = READ_ONCE(iq->pkt_in_done); netdev_dbg(iq->netdev, "enabling intr for Q-%u\n", iq->q_no); - if (iq->pkts_processed) { - writel(iq->pkts_processed, iq->inst_cnt_reg); - iq->pkt_in_done -= iq->pkts_processed; - iq->pkts_processed = 0; + if (pkts_processed) { + writel(pkts_processed, iq->inst_cnt_reg); + readl(iq->inst_cnt_reg); + WRITE_ONCE(iq->pkt_in_done, (pkt_in_done - pkts_processed)); + WRITE_ONCE(iq->pkts_processed, 0); } - if (oq->last_pkt_count - pkts_pend) { - writel(oq->last_pkt_count - pkts_pend, oq->pkts_sent_reg); - oq->last_pkt_count = pkts_pend; + if (last_pkt_count - pkts_pend) { + writel(last_pkt_count - pkts_pend, oq->pkts_sent_reg); + readl(oq->pkts_sent_reg); + WRITE_ONCE(oq->last_pkt_count, pkts_pend); } /* Flush the previous wrties before writing to RESEND bit */ - wmb(); + smp_wmb(); +} + +/** + * octep_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_enable_ioq_irq(struct octep_iq *iq, struct octep_oq *oq) +{ writeq(1UL << OCTEP_OQ_INTR_RESEND_BIT, oq->pkts_sent_reg); writeq(1UL << OCTEP_IQ_INTR_RESEND_BIT, iq->inst_cnt_reg); } @@ -602,7 +617,8 @@ static int octep_napi_poll(struct napi_struct *napi, int budget) if (tx_pending || rx_done >= budget) return budget; - napi_complete(napi); + octep_update_pkt(ioq_vector->iq, ioq_vector->oq); + napi_complete_done(napi, rx_done); octep_enable_ioq_irq(ioq_vector->iq, ioq_vector->oq); return rx_done; } diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c index 82b6b19e76b4..11f1b45d0f92 100644 --- a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c +++ b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c @@ -318,10 +318,16 @@ static int octep_oq_check_hw_for_pkts(struct octep_device *oct, struct octep_oq *oq) { u32 pkt_count, new_pkts; + u32 last_pkt_count, pkts_pending; pkt_count = readl(oq->pkts_sent_reg); - new_pkts = pkt_count - oq->last_pkt_count; + last_pkt_count = READ_ONCE(oq->last_pkt_count); + new_pkts = pkt_count - last_pkt_count; + if (pkt_count < last_pkt_count) { + dev_err(oq->dev, "OQ-%u pkt_count(%u) < oq->last_pkt_count(%u)\n", + oq->q_no, pkt_count, last_pkt_count); + } /* Clear the hardware packets counter register if the rx queue is * being processed continuously with-in a single interrupt and * reached half its max value. @@ -332,8 +338,9 @@ static int octep_oq_check_hw_for_pkts(struct octep_device *oct, pkt_count = readl(oq->pkts_sent_reg); new_pkts += pkt_count; } - oq->last_pkt_count = pkt_count; - oq->pkts_pending += new_pkts; + WRITE_ONCE(oq->last_pkt_count, pkt_count); + pkts_pending = READ_ONCE(oq->pkts_pending); + WRITE_ONCE(oq->pkts_pending, (pkts_pending + new_pkts)); return new_pkts; } @@ -408,7 +415,7 @@ static int __octep_oq_process_rx(struct octep_device *oct, u16 rx_ol_flags; u32 read_idx; - read_idx = oq->host_read_idx; + read_idx = READ_ONCE(oq->host_read_idx); rx_bytes = 0; desc_used = 0; for (pkt = 0; pkt < pkts_to_process; pkt++) { @@ -493,7 +500,7 @@ static int __octep_oq_process_rx(struct octep_device *oct, napi_gro_receive(oq->napi, skb); } - oq->host_read_idx = read_idx; + WRITE_ONCE(oq->host_read_idx, read_idx); oq->refill_count += desc_used; oq->stats->packets += pkt; oq->stats->bytes += rx_bytes; @@ -516,22 +523,26 @@ int octep_oq_process_rx(struct octep_oq *oq, int budget) { u32 pkts_available, pkts_processed, total_pkts_processed; struct octep_device *oct = oq->octep_dev; + u32 pkts_pending; pkts_available = 0; pkts_processed = 0; total_pkts_processed = 0; while (total_pkts_processed < budget) { /* update pending count only when current one exhausted */ - if (oq->pkts_pending == 0) + pkts_pending = READ_ONCE(oq->pkts_pending); + if (pkts_pending == 0) octep_oq_check_hw_for_pkts(oct, oq); + pkts_pending = READ_ONCE(oq->pkts_pending); pkts_available = min(budget - total_pkts_processed, - oq->pkts_pending); + pkts_pending); if (!pkts_available) break; pkts_processed = __octep_oq_process_rx(oct, oq, pkts_available); - oq->pkts_pending -= pkts_processed; + pkts_pending = READ_ONCE(oq->pkts_pending); + WRITE_ONCE(oq->pkts_pending, (pkts_pending - pkts_processed)); total_pkts_processed += pkts_processed; } -- 2.47.0