On Fri, Oct 04, 2019 at 12:21:33PM +0300, Ioana Ciornei wrote:
> From: Ioana Radulescu <ruxandra.radule...@nxp.com>
>
> Throughout the driver there are several places where we wait
> indefinitely for DPIO portal commands to be executed, while
> the portal returns a busy response code.
>
> Even though in theory we are guaranteed the portals become
> available eventually, in practice the QBMan hardware module
> may become unresponsive in various corner cases.
>
> Make sure we can never get stuck in an infinite while loop
> by adding a retry counter for all portal commands.
>
> Signed-off-by: Ioana Radulescu <ruxandra.radule...@nxp.com>
> Signed-off-by: Ioana Ciornei <ioana.cior...@nxp.com>
> ---
> drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 30
> ++++++++++++++++++++----
> drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h | 8 +++++++
> 2 files changed, 33 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> index 2c5072fa9aa0..29702756734c 100644
> --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> @@ -221,6 +221,7 @@ static void xdp_release_buf(struct dpaa2_eth_priv *priv,
> struct dpaa2_eth_channel *ch,
> dma_addr_t addr)
> {
> + int retries = 0;
> int err;
>
> ch->xdp.drop_bufs[ch->xdp.drop_cnt++] = addr;
> @@ -229,8 +230,11 @@ static void xdp_release_buf(struct dpaa2_eth_priv *priv,
>
> while ((err = dpaa2_io_service_release(ch->dpio, priv->bpid,
> ch->xdp.drop_bufs,
> - ch->xdp.drop_cnt)) == -EBUSY)
> + ch->xdp.drop_cnt)) == -EBUSY) {
> + if (retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES)
> + break;
> cpu_relax();
> + }
>
> if (err) {
> free_bufs(priv, ch->xdp.drop_bufs, ch->xdp.drop_cnt);
> @@ -458,7 +462,7 @@ static int consume_frames(struct dpaa2_eth_channel *ch,
> struct dpaa2_eth_fq *fq = NULL;
> struct dpaa2_dq *dq;
> const struct dpaa2_fd *fd;
> - int cleaned = 0;
> + int cleaned = 0, retries = 0;
> int is_last;
>
> do {
> @@ -469,6 +473,11 @@ static int consume_frames(struct dpaa2_eth_channel *ch,
> * the store until we get some sort of valid response
> * token (either a valid frame or an "empty dequeue")
> */
> + if (retries++ >= DPAA2_ETH_SWP_BUSY_RETRIES) {
> + netdev_err_once(priv->net_dev,
> + "Unable to read a valid dequeue
> response\n");
> + return 0;
> + }
> continue;
Hi Ioana
It seems a bit odd that here you could return -ETIMEDOUT, but you
print an error, and return 0. But in the two cases above in void
functions, you don't print anything.
Please at least return -ETIMEDOUT when you can.
Andrew
