net: mana: Enable debugfs files for MANA device

Implement debugfs in MANA driver to be able to view RX,TX,EQ queue
specific attributes and dump their gdma queues.
These dumps can be used by other userspace utilities to improve
debuggability and troubleshooting

Following files are added in debugfs:

/sys/kernel/debug/mana/
|-------------- 1
    |--------------- EQs
    |                 |------- eq0
    |                 |          |---head
    |                 |          |---tail
    |                 |          |---eq_dump
    |                 |------- eq1
    |                 .
    |                 .
    |
    |--------------- adapter-MTU
    |--------------- vport0
                      |------- RX-0
                      |          |---cq_budget
                      |          |---cq_dump
                      |          |---cq_head
                      |          |---cq_tail
                      |          |---rq_head
                      |          |---rq_nbuf
                      |          |---rq_tail
                      |          |---rxq_dump
                      |------- RX-1
                      .
                      .
                      |------- TX-0
                      |          |---cq_budget
                      |          |---cq_dump
                      |          |---cq_head
                      |          |---cq_tail
                      |          |---sq_head
                      |          |---sq_pend_skb_qlen
                      |          |---sq_tail
                      |          |---txq_dump
                      |------- TX-1
                      .
                      .

Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 104 insertions, 1 deletions

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index c47266d1c7c2..57ac732e7707 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -3,6 +3,7 @@
 
 #include <uapi/linux/bpf.h>
 
+#include <linux/debugfs.h>
 #include <linux/inetdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
@@ -30,6 +31,21 @@ static void mana_adev_idx_free(int idx)
 	ida_free(&mana_adev_ida, idx);
 }
 
+static ssize_t mana_dbg_q_read(struct file *filp, char __user *buf, size_t count,
+			       loff_t *pos)
+{
+	struct gdma_queue *gdma_q = filp->private_data;
+
+	return simple_read_from_buffer(buf, count, pos, gdma_q->queue_mem_ptr,
+				       gdma_q->queue_size);
+}
+
+static const struct file_operations mana_dbg_q_fops = {
+	.owner  = THIS_MODULE,
+	.open   = simple_open,
+	.read   = mana_dbg_q_read,
+};
+
 /* Microsoft Azure Network Adapter (MANA) functions */
 
 static int mana_open(struct net_device *ndev)
@@ -721,6 +737,13 @@ static const struct net_device_ops mana_devops = {
 
 static void mana_cleanup_port_context(struct mana_port_context *apc)
 {
+	/*
+	 * at this point all dir/files under the vport directory
+	 * are already cleaned up.
+	 * We are sure the apc->mana_port_debugfs remove will not
+	 * cause any freed memory access issues
+	 */
+	debugfs_remove(apc->mana_port_debugfs);
 	kfree(apc->rxqs);
 	apc->rxqs = NULL;
 }
@@ -943,6 +966,8 @@ static int mana_query_device_cfg(struct mana_context *ac, u32 proto_major_ver,
 	else
 		gc->adapter_mtu = ETH_FRAME_LEN;
 
+	debugfs_create_u16("adapter-MTU", 0400, gc->mana_pci_debugfs, &gc->adapter_mtu);
+
 	return 0;
 }
 
@@ -1228,6 +1253,8 @@ static void mana_destroy_eq(struct mana_context *ac)
 	if (!ac->eqs)
 		return;
 
+	debugfs_remove_recursive(ac->mana_eqs_debugfs);
+
 	for (i = 0; i < gc->max_num_queues; i++) {
 		eq = ac->eqs[i].eq;
 		if (!eq)
@@ -1240,6 +1267,18 @@ static void mana_destroy_eq(struct mana_context *ac)
 	ac->eqs = NULL;
 }
 
+static void mana_create_eq_debugfs(struct mana_context *ac, int i)
+{
+	struct mana_eq eq = ac->eqs[i];
+	char eqnum[32];
+
+	sprintf(eqnum, "eq%d", i);
+	eq.mana_eq_debugfs = debugfs_create_dir(eqnum, ac->mana_eqs_debugfs);
+	debugfs_create_u32("head", 0400, eq.mana_eq_debugfs, &eq.eq->head);
+	debugfs_create_u32("tail", 0400, eq.mana_eq_debugfs, &eq.eq->tail);
+	debugfs_create_file("eq_dump", 0400, eq.mana_eq_debugfs, eq.eq, &mana_dbg_q_fops);
+}
+
 static int mana_create_eq(struct mana_context *ac)
 {
 	struct gdma_dev *gd = ac->gdma_dev;
@@ -1260,11 +1299,14 @@ static int mana_create_eq(struct mana_context *ac)
 	spec.eq.context = ac->eqs;
 	spec.eq.log2_throttle_limit = LOG2_EQ_THROTTLE;
 
+	ac->mana_eqs_debugfs = debugfs_create_dir("EQs", gc->mana_pci_debugfs);
+
 	for (i = 0; i < gc->max_num_queues; i++) {
 		spec.eq.msix_index = (i + 1) % gc->num_msix_usable;
 		err = mana_gd_create_mana_eq(gd, &spec, &ac->eqs[i].eq);
 		if (err)
 			goto out;
+		mana_create_eq_debugfs(ac, i);
 	}
 
 	return 0;
@@ -1871,6 +1913,8 @@ static void mana_destroy_txq(struct mana_port_context *apc)
 		return;
 
 	for (i = 0; i < apc->num_queues; i++) {
+		debugfs_remove_recursive(apc->tx_qp[i].mana_tx_debugfs);
+
 		napi = &apc->tx_qp[i].tx_cq.napi;
 		if (apc->tx_qp[i].txq.napi_initialized) {
 			napi_synchronize(napi);
@@ -1889,6 +1933,31 @@ static void mana_destroy_txq(struct mana_port_context *apc)
 	apc->tx_qp = NULL;
 }
 
+static void mana_create_txq_debugfs(struct mana_port_context *apc, int idx)
+{
+	struct mana_tx_qp *tx_qp = &apc->tx_qp[idx];
+	char qnum[32];
+
+	sprintf(qnum, "TX-%d", idx);
+	tx_qp->mana_tx_debugfs = debugfs_create_dir(qnum, apc->mana_port_debugfs);
+	debugfs_create_u32("sq_head", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->txq.gdma_sq->head);
+	debugfs_create_u32("sq_tail", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->txq.gdma_sq->tail);
+	debugfs_create_u32("sq_pend_skb_qlen", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->txq.pending_skbs.qlen);
+	debugfs_create_u32("cq_head", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->tx_cq.gdma_cq->head);
+	debugfs_create_u32("cq_tail", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->tx_cq.gdma_cq->tail);
+	debugfs_create_u32("cq_budget", 0400, tx_qp->mana_tx_debugfs,
+			   &tx_qp->tx_cq.budget);
+	debugfs_create_file("txq_dump", 0400, tx_qp->mana_tx_debugfs,
+			    tx_qp->txq.gdma_sq, &mana_dbg_q_fops);
+	debugfs_create_file("cq_dump", 0400, tx_qp->mana_tx_debugfs,
+			    tx_qp->tx_cq.gdma_cq, &mana_dbg_q_fops);
+}
+
 static int mana_create_txq(struct mana_port_context *apc,
 			   struct net_device *net)
 {
@@ -2000,6 +2069,8 @@ static int mana_create_txq(struct mana_port_context *apc,
 
 		gc->cq_table[cq->gdma_id] = cq->gdma_cq;
 
+		mana_create_txq_debugfs(apc, i);
+
 		netif_napi_add_tx(net, &cq->napi, mana_poll);
 		napi_enable(&cq->napi);
 		txq->napi_initialized = true;
@@ -2027,6 +2098,8 @@ static void mana_destroy_rxq(struct mana_port_context *apc,
 	if (!rxq)
 		return;
 
+	debugfs_remove_recursive(rxq->mana_rx_debugfs);
+
 	napi = &rxq->rx_cq.napi;
 
 	if (napi_initialized) {
@@ -2308,6 +2381,28 @@ out:
 	return NULL;
 }
 
+static void mana_create_rxq_debugfs(struct mana_port_context *apc, int idx)
+{
+	struct mana_rxq *rxq;
+	char qnum[32];
+
+	rxq = apc->rxqs[idx];
+
+	sprintf(qnum, "RX-%d", idx);
+	rxq->mana_rx_debugfs = debugfs_create_dir(qnum, apc->mana_port_debugfs);
+	debugfs_create_u32("rq_head", 0400, rxq->mana_rx_debugfs, &rxq->gdma_rq->head);
+	debugfs_create_u32("rq_tail", 0400, rxq->mana_rx_debugfs, &rxq->gdma_rq->tail);
+	debugfs_create_u32("rq_nbuf", 0400, rxq->mana_rx_debugfs, &rxq->num_rx_buf);
+	debugfs_create_u32("cq_head", 0400, rxq->mana_rx_debugfs,
+			   &rxq->rx_cq.gdma_cq->head);
+	debugfs_create_u32("cq_tail", 0400, rxq->mana_rx_debugfs,
+			   &rxq->rx_cq.gdma_cq->tail);
+	debugfs_create_u32("cq_budget", 0400, rxq->mana_rx_debugfs, &rxq->rx_cq.budget);
+	debugfs_create_file("rxq_dump", 0400, rxq->mana_rx_debugfs, rxq->gdma_rq, &mana_dbg_q_fops);
+	debugfs_create_file("cq_dump", 0400, rxq->mana_rx_debugfs, rxq->rx_cq.gdma_cq,
+			    &mana_dbg_q_fops);
+}
+
 static int mana_add_rx_queues(struct mana_port_context *apc,
 			      struct net_device *ndev)
 {
@@ -2326,6 +2421,8 @@ static int mana_add_rx_queues(struct mana_port_context *apc,
 		u64_stats_init(&rxq->stats.syncp);
 
 		apc->rxqs[i] = rxq;
+
+		mana_create_rxq_debugfs(apc, i);
 	}
 
 	apc->default_rxobj = apc->rxqs[0]->rxobj;
@@ -2518,14 +2615,19 @@ void mana_query_gf_stats(struct mana_port_context *apc)
 static int mana_init_port(struct net_device *ndev)
 {
 	struct mana_port_context *apc = netdev_priv(ndev);
+	struct gdma_dev *gd = apc->ac->gdma_dev;
 	u32 max_txq, max_rxq, max_queues;
 	int port_idx = apc->port_idx;
+	struct gdma_context *gc;
+	char vport[32];
 	int err;
 
 	err = mana_init_port_context(apc);
 	if (err)
 		return err;
 
+	gc = gd->gdma_context;
+
 	err = mana_query_vport_cfg(apc, port_idx, &max_txq, &max_rxq,
 				   &apc->indir_table_sz);
 	if (err) {
@@ -2542,7 +2644,8 @@ static int mana_init_port(struct net_device *ndev)
 		apc->num_queues = apc->max_queues;
 
 	eth_hw_addr_set(ndev, apc->mac_addr);
-
+	sprintf(vport, "vport%d", port_idx);
+	apc->mana_port_debugfs = debugfs_create_dir(vport, gc->mana_pci_debugfs);
 	return 0;
 
 reset_apc: