Re: [Intel-wired-lan] [PATCH iwl-next v1 3/6] ice: add Tx hang devlink health reporter

From: Simon Horman
Date: Mon Jul 08 2024 - 08:41:08 EST


On Wed, Jul 03, 2024 at 08:59:19AM -0400, Mateusz Polchlopek wrote:
> From: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>
>
> Add Tx hang devlink health reporter, see struct ice_tx_hang_event to see
> what is reported.
>
> Subsequent commits will extend it by more info, for now it dumps
> descriptors with little metadata.
>
> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>
> Reviewed-by: Igor Bagnucki <igor.bagnucki@xxxxxxxxx>
> Reviewed-by: Wojciech Drewek <wojciech.drewek@xxxxxxxxx>
> Signed-off-by: Mateusz Polchlopek <mateusz.polchlopek@xxxxxxxxx>

...

> +/**
> + * ice_fmsg_put_ptr - put hex value of pointer into fmsg
> + *
> + * @fmsg: devlink fmsg under construction
> + * @name: name to pass
> + * @ptr: 64 bit value to print as hex and put into fmsg
> + */
> +static void ice_fmsg_put_ptr(struct devlink_fmsg *fmsg, const char *name,
> + void *ptr)
> +{
> + char buf[sizeof(ptr) * 3];
> +
> + sprintf(buf, "%p", ptr);
> + devlink_fmsg_put(fmsg, name, buf);
> +}

...

> +static int ice_tx_hang_reporter_dump(struct devlink_health_reporter *reporter,
> + struct devlink_fmsg *fmsg, void *priv_ctx,
> + struct netlink_ext_ack *extack)
> +{
> + struct ice_tx_hang_event *event = priv_ctx;
> +
> + devlink_fmsg_obj_nest_start(fmsg);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, head);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, intr);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, vsi_num);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, queue);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, next_to_clean);
> + ICE_DEVLINK_FMSG_PUT_FIELD(fmsg, event, next_to_use);
> + devlink_fmsg_put(fmsg, "irq-mapping", event->tx_ring->q_vector->name);
> + ice_fmsg_put_ptr(fmsg, "desc-ptr", event->tx_ring->desc);
> + ice_fmsg_put_ptr(fmsg, "dma-ptr", (void *)event->tx_ring->dma);

As reported by the kernel test robot, GCC 13 complains about this cast:

.../devlink_health.c: In function 'ice_tx_hang_reporter_dump':
.../devlink_health.c:76:43: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
76 | ice_fmsg_put_ptr(fmsg, "dma-ptr", (void *)event->tx_ring->dma);
|

Perhaps a good solution is to add a helper similar to ice_fmsg_put_ptr,
but which takes a dma_buf_t rather than a void * as it's last argument.

> + devlink_fmsg_binary_pair_put(fmsg, "desc", event->tx_ring->desc,
> + size_mul(event->tx_ring->count,
> + sizeof(struct ice_tx_desc)));
> + devlink_fmsg_obj_nest_end(fmsg);
> +
> + return 0;
> +}