Fri, Jun 23, 2023 at 09:29:15AM CEST, schakrabarti@linux.microsoft.com wrote:

From: Souradeep Chakrabarti schakrabarti@linux.microsoft.com

This patch addresses the VF unload issue, where mana_dealloc_queues()

double space here ^^

gets stuck in infinite while loop, because of host unresponsiveness. It adds a timeout in the while loop, to fix it.

Also this patch adds a new attribute in mana_context, which gets set when mana_hwc_send_request() hits a timeout because of host unresponsiveness. This flag then helps to avoid the timeouts in successive calls.

You aparently combine 2 patches together. Please split.

Signed-off-by: Souradeep Chakrabarti schakrabarti@linux.microsoft.com

Please provide a "Fixes" tag with pointer to the commit that introduced the problem.

---

V1 -> V2:

• Added net branch
• Removed the typecasting to (struct mana_context*) of void pointer
• Repositioned timeout variable in mana_dealloc_queues()
• Repositioned vf_unload_timeout in mana_context struct, to utilise the

6 bytes hole

.../net/ethernet/microsoft/mana/gdma_main.c | 4 +++- .../net/ethernet/microsoft/mana/hw_channel.c | 12 ++++++++++- drivers/net/ethernet/microsoft/mana/mana_en.c | 21 +++++++++++++++++-- include/net/mana/mana.h | 2 ++ 4 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index 8f3f78b68592..6411f01be0d9 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -946,10 +946,12 @@ int mana_gd_deregister_device(struct gdma_dev *gd) struct gdma_context *gc = gd->gdma_context; struct gdma_general_resp resp = {}; struct gdma_general_req req = {};

• struct mana_context *ac; int err;

  if (gd->pdid == INVALID_PDID) return -EINVAL;

• ac = gd->driver_data;

  mana_gd_init_req_hdr(&req.hdr, GDMA_DEREGISTER_DEVICE, sizeof(req), sizeof(resp));

@@ -957,7 +959,7 @@ int mana_gd_deregister_device(struct gdma_dev *gd) req.hdr.dev_id = gd->dev_id;

err = mana_gd_send_request(gc, sizeof(req), &req, sizeof(resp), &resp);

• if (err || resp.hdr.status) {

• if ((err || resp.hdr.status) && !ac->vf_unload_timeout) { dev_err(gc->dev, "Failed to deregister device: %d, 0x%x\n", err, resp.hdr.status); if (!err)

diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c b/drivers/net/ethernet/microsoft/mana/hw_channel.c index 9d1507eba5b9..492cb2c6e2cb 100644 --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c @@ -1,8 +1,10 @@ // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause /* Copyright (c) 2021, Microsoft Corporation. */

+#include "asm-generic/errno.h" #include <net/mana/gdma.h> #include <net/mana/hw_channel.h> +#include <net/mana/mana.h>

static int mana_hwc_get_msg_index(struct hw_channel_context *hwc, u16 *msg_id) { @@ -786,12 +788,19 @@ int mana_hwc_send_request(struct hw_channel_context *hwc, u32 req_len, struct hwc_wq *txq = hwc->txq; struct gdma_req_hdr *req_msg; struct hwc_caller_ctx *ctx;

• struct mana_context *ac; u32 dest_vrcq = 0; u32 dest_vrq = 0; u16 msg_id; int err;

  mana_hwc_get_msg_index(hwc, &msg_id);

• ac = hwc->gdma_dev->driver_data;

• if (ac->vf_unload_timeout) {

• dev_err(hwc->dev, "HWC: vport is already unloaded.\n");
  

• err = -ETIMEDOUT;
  

• goto out;
  

• }

  tx_wr = &txq->msg_buf->reqs[msg_id];

@@ -825,9 +834,10 @@ int mana_hwc_send_request(struct hw_channel_context *hwc, u32 req_len, goto out; }

• if (!wait_for_completion_timeout(&ctx->comp_event, 30 * HZ)) {

• if (!wait_for_completion_timeout(&ctx->comp_event, 5 * HZ)) { dev_err(hwc->dev, "HWC: Request timed out!\n"); err = -ETIMEDOUT;

• ac->vf_unload_timeout = true;
  

  goto out; }

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index d907727c7b7a..cb2080b3a00c 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -2329,7 +2329,10 @@ static int mana_dealloc_queues(struct net_device *ndev) { struct mana_port_context *apc = netdev_priv(ndev); struct gdma_dev *gd = apc->ac->gdma_dev;

• unsigned long timeout; struct mana_txq *txq;

• struct sk_buff *skb;

• struct mana_cq *cq; int i, err;

  if (apc->port_is_up)

@@ -2348,13 +2351,26 @@ static int mana_dealloc_queues(struct net_device *ndev) * * Drain all the in-flight TX packets */

• timeout = jiffies + 120 * HZ; for (i = 0; i < apc->num_queues; i++) { txq = &apc->tx_qp[i].txq;

• while (atomic_read(&txq->pending_sends) > 0)
  

• while (atomic_read(&txq->pending_sends) > 0 &&
  

•        time_before(jiffies, timeout)) {
  usleep_range(1000, 2000);
  

• }
  

  }

• for (i = 0; i < apc->num_queues; i++) {

• txq = &apc->tx_qp[i].txq;
  

• cq = &apc->tx_qp[i].tx_cq;
  

• while (atomic_read(&txq->pending_sends)) {
  

• 	skb = skb_dequeue(&txq->pending_skbs);
  

• 	mana_unmap_skb(skb, apc);
  

• 	napi_consume_skb(skb, cq->budget);
  

• 	atomic_sub(1, &txq->pending_sends);
  

• }
  

• } /* We're 100% sure the queues can no longer be woken up, because

  • we're sure now mana_poll_tx_cq() can't be running.

  */

@@ -2605,6 +2621,7 @@ int mana_probe(struct gdma_dev *gd, bool resuming) } }

• ac->vf_unload_timeout = false;

Pointless init. You have the struct zeroed during allocation.

err = add_adev(gd); out: if (err) diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h index 9eef19972845..5f5affdca1eb 100644 --- a/include/net/mana/mana.h +++ b/include/net/mana/mana.h @@ -358,6 +358,8 @@ struct mana_context {

u16 num_ports;

• bool vf_unload_timeout;

• struct mana_eq *eqs;

  struct net_device *ports[MAX_PORTS_IN_MANA_DEV];

-- 2.34.1