diff mbox series

[net-next,4/7] net: mscc: ocelot: don't rely on cached verify_status in ocelot_port_get_mm()

Message ID 20230415170551.3939607-5-vladimir.oltean@nxp.com
State New
Headers
Series Ocelot/Felix driver support for preemptible traffic classes |

Commit Message

Vladimir Oltean April 15, 2023, 5:05 p.m. UTC 
  ocelot_mm_update_port_status() updates mm->verify_status, but when the
verification state of a port changes, an IRQ isn't emitted, but rather,
only when the verification state reaches one of the final states (like
DISABLED, FAILED, SUCCEEDED) - things that would affect mm->tx_active,
which is what the IRQ *is* actually emitted for.

That is to say, user space may miss reports of an intermediary MAC Merge
verification state (like from INITIAL to VERIFYING), unless there was an
IRQ notifying the driver of the change in mm->tx_active as well.

This is not a huge deal, but for reliable reporting to user space, let's
call ocelot_mm_update_port_status() synchronously from
ocelot_port_get_mm(), which makes user space see the current MM status.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Diff: patch is new.

 drivers/net/ethernet/mscc/ocelot_mm.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Florian Fainelli April 17, 2023, 12:59 p.m. UTC | #1 
On 4/15/2023 10:05 AM, Vladimir Oltean wrote:
> ocelot_mm_update_port_status() updates mm->verify_status, but when the
> verification state of a port changes, an IRQ isn't emitted, but rather,
> only when the verification state reaches one of the final states (like
> DISABLED, FAILED, SUCCEEDED) - things that would affect mm->tx_active,
> which is what the IRQ *is* actually emitted for.
> 
> That is to say, user space may miss reports of an intermediary MAC Merge
> verification state (like from INITIAL to VERIFYING), unless there was an
> IRQ notifying the driver of the change in mm->tx_active as well.
> 
> This is not a huge deal, but for reliable reporting to user space, let's
> call ocelot_mm_update_port_status() synchronously from
> ocelot_port_get_mm(), which makes user space see the current MM status.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Simon Horman April 17, 2023, 1:01 p.m. UTC | #2 
On Sat, Apr 15, 2023 at 08:05:48PM +0300, Vladimir Oltean wrote:
> ocelot_mm_update_port_status() updates mm->verify_status, but when the
> verification state of a port changes, an IRQ isn't emitted, but rather,
> only when the verification state reaches one of the final states (like
> DISABLED, FAILED, SUCCEEDED) - things that would affect mm->tx_active,
> which is what the IRQ *is* actually emitted for.
> 
> That is to say, user space may miss reports of an intermediary MAC Merge
> verification state (like from INITIAL to VERIFYING), unless there was an
> IRQ notifying the driver of the change in mm->tx_active as well.
> 
> This is not a huge deal, but for reliable reporting to user space, let's
> call ocelot_mm_update_port_status() synchronously from
> ocelot_port_get_mm(), which makes user space see the current MM status.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Simon Horman <simon.horman@corigine.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mscc/ocelot_mm.c b/drivers/net/ethernet/mscc/ocelot_mm.c
index ce6429d46814..3e458f72f645 100644
--- a/drivers/net/ethernet/mscc/ocelot_mm.c
+++ b/drivers/net/ethernet/mscc/ocelot_mm.c
@@ -205,6 +205,7 @@  int ocelot_port_get_mm(struct ocelot *ocelot, int port,
 	state->tx_min_frag_size = ethtool_mm_frag_size_add_to_min(add_frag_size);
 	state->rx_min_frag_size = ETH_ZLEN;
 
+	ocelot_mm_update_port_status(ocelot, port);
 	state->verify_status = mm->verify_status;
 	state->tx_active = mm->tx_active;