diff mbox series

[net-next] liquidio: Allow RX descriptors to be consumed before disabling NAPI.

Message ID 20180314231747.GA1263@felix-thinkpad.cavium.com
State Changes Requested, archived
Delegated to: David Miller
Headers show
Series [net-next] liquidio: Allow RX descriptors to be consumed before disabling NAPI. | expand

Commit Message

Manlunas, Felix March 14, 2018, 11:17 p.m. UTC 
From: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>

Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Acked-by: Derek Chickles <derek.chickles@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
---
 drivers/net/ethernet/cavium/liquidio/lio_core.c    | 23 ++++++++++++++++++++
 drivers/net/ethernet/cavium/liquidio/lio_main.c    | 25 +++++++++++++---------
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c | 23 ++++++++++++--------
 .../net/ethernet/cavium/liquidio/octeon_network.h  |  1 +
 4 files changed, 53 insertions(+), 19 deletions(-)

Comments

David Miller March 17, 2018, 9:01 p.m. UTC | #1 
From: Felix Manlunas <felix.manlunas@cavium.com>
Date: Wed, 14 Mar 2018 16:17:47 -0700

> From: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
> 
> Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
> Acked-by: Derek Chickles <derek.chickles@cavium.com>
> Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>

This must have a reasonable commit message added, and that commit
message must explain in detail what exactly is happening here.

But since I did read the patch I do not think that doing a looping
sleeping read is the way to fix this problem.

Instead, you should find some way to wait on the specific event that
needs to occur.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_core.c b/drivers/net/ethernet/cavium/liquidio/lio_core.c
index e7b6eb8..8e4716a 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_core.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_core.c
@@ -1157,3 +1157,26 @@  int liquidio_change_mtu(struct net_device *netdev, int new_mtu)
 	octeon_free_soft_command(oct, sc);
 	return 0;
 }
+
+int lio_wait_for_clean_oq(struct octeon_device *oct)
+{
+	int retry = 100, pending_pkts = 0;
+	int idx;
+
+	do {
+		pending_pkts = 0;
+
+		for (idx = 0; idx < MAX_OCTEON_OUTPUT_QUEUES(oct); idx++) {
+			if (!(oct->io_qmask.oq & BIT_ULL(idx)))
+				continue;
+			pending_pkts +=
+				atomic_read(&oct->droq[idx]->pkts_pending);
+		}
+
+		if (pending_pkts > 0)
+			schedule_timeout_uninterruptible(1);
+
+	} while (retry-- && pending_pkts);
+
+	return pending_pkts;
+}
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_main.c b/drivers/net/ethernet/cavium/liquidio/lio_main.c
index 140085b..345fe6e 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -2240,16 +2240,6 @@  static int liquidio_stop(struct net_device *netdev)
 	struct octeon_device *oct = lio->oct_dev;
 	struct napi_struct *napi, *n;
 
-	if (oct->props[lio->ifidx].napi_enabled) {
-		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
-			napi_disable(napi);
-
-		oct->props[lio->ifidx].napi_enabled = 0;
-
-		if (OCTEON_CN23XX_PF(oct))
-			oct->droq[0]->ops.poll_mode = 0;
-	}
-
 	ifstate_reset(lio, LIO_IFSTATE_RUNNING);
 
 	netif_tx_disable(netdev);
@@ -2275,6 +2265,21 @@  static int liquidio_stop(struct net_device *netdev)
 		lio->ptp_clock = NULL;
 	}
 
+	/* Wait for any pending Rx descriptors */
+	if (lio_wait_for_clean_oq(oct))
+		netif_info(lio, rx_err, lio->netdev,
+			   "Proceeding with stop interface after partial RX desc processing\n");
+
+	if (oct->props[lio->ifidx].napi_enabled == 1) {
+		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
+			napi_disable(napi);
+
+		oct->props[lio->ifidx].napi_enabled = 0;
+
+		if (OCTEON_CN23XX_PF(oct))
+			oct->droq[0]->ops.poll_mode = 0;
+	}
+
 	dev_info(&oct->pci_dev->dev, "%s interface is stopped\n", netdev->name);
 
 	return 0;
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
index 3342d64..66655df 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -1281,15 +1281,6 @@  static int liquidio_stop(struct net_device *netdev)
 	/* tell Octeon to stop forwarding packets to host */
 	send_rx_ctrl_cmd(lio, 0);
 
-	if (oct->props[lio->ifidx].napi_enabled) {
-		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
-			napi_disable(napi);
-
-		oct->props[lio->ifidx].napi_enabled = 0;
-
-		oct->droq[0]->ops.poll_mode = 0;
-	}
-
 	netif_info(lio, ifdown, lio->netdev, "Stopping interface!\n");
 	/* Inform that netif carrier is down */
 	lio->intf_open = 0;
@@ -1302,6 +1293,20 @@  static int liquidio_stop(struct net_device *netdev)
 
 	txqs_stop(netdev);
 
+	/* Wait for any pending Rx descriptors */
+	if (lio_wait_for_clean_oq(oct))
+		netif_info(lio, rx_err, lio->netdev,
+			   "Proceeding with stop interface after partial RX desc processing\n");
+
+	if (oct->props[lio->ifidx].napi_enabled == 1) {
+		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
+			napi_disable(napi);
+
+		oct->props[lio->ifidx].napi_enabled = 0;
+
+		oct->droq[0]->ops.poll_mode = 0;
+	}
+
 	dev_info(&oct->pci_dev->dev, "%s interface is stopped\n", netdev->name);
 
 	return 0;
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_network.h b/drivers/net/ethernet/cavium/liquidio/octeon_network.h
index 76803a5..b7ee2d3 100644
--- a/drivers/net/ethernet/cavium/liquidio/octeon_network.h
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_network.h
@@ -190,6 +190,7 @@  irqreturn_t liquidio_msix_intr_handler(int irq __attribute__((unused)),
 
 int octeon_setup_interrupt(struct octeon_device *oct, u32 num_ioqs);
 
+int lio_wait_for_clean_oq(struct octeon_device *oct);
 /**
  * \brief Register ethtool operations
  * @param netdev    pointer to network device