[dpdk-dev] [PATCH] common/sfc_efx/base: do not validate MAE action COUNT order

[dpdk-dev] [PATCH] common/sfc_efx/base: do not validate MAE action COUNT order

[Ivan Malov]

In DPDK + Open vSwitch use case, action COUNT is always the
first one to be added. In particular, it goes before action
DECAP in that use case. The current code enforces the right
order (DECAP goes before COUNT), and this provokes failures.
As an exception, do not validate the order for action COUNT.

Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>
---
 drivers/common/sfc_efx/base/efx.h     | 12 ++++++++++++
 drivers/common/sfc_efx/base/efx_mae.c |  1 +
 2 files changed, 13 insertions(+)

diff --git a/drivers/common/sfc_efx/base/efx.h b/drivers/common/sfc_efx/base/efx.h
index b2301b845a..24e1314cc3 100644
--- a/drivers/common/sfc_efx/base/efx.h
+++ b/drivers/common/sfc_efx/base/efx.h
@@ -4310,6 +4310,18 @@ efx_mae_action_set_populate_encap(
 /*
  * Use efx_mae_action_set_fill_in_counter_id() to set ID of a counter
  * in the specification prior to action set allocation.
+ *
+ * NOTICE: the HW will conduct action COUNT after actions DECAP,
+ * VLAN_POP, VLAN_PUSH (if any) have been applied to the packet,
+ * but, as a workaround, this order is not validated by the API.
+ *
+ * The workaround helps to unblock DPDK + Open vSwitch use case.
+ * In Open vSwitch, this action is always the first to be added,
+ * in particular, it's known to be inserted before action DECAP,
+ * so enforcing the right order here would cause runtime errors.
+ * The existing behaviour in Open vSwitch is unlikely to change
+ * any time soon, and the workaround is a good solution because
+ * in fact the real COUNT order is a don't care to Open vSwitch.
  */
 LIBEFX_API
 extern	__checkReturn			efx_rc_t
diff --git a/drivers/common/sfc_efx/base/efx_mae.c b/drivers/common/sfc_efx/base/efx_mae.c
index 47e809a22f..c22206e227 100644
--- a/drivers/common/sfc_efx/base/efx_mae.c
+++ b/drivers/common/sfc_efx/base/efx_mae.c
@@ -1547,6 +1547,7 @@ static const uint32_t efx_mae_action_ordered_map =
  * strictly ordered actions.
  */
 static const uint32_t efx_mae_action_nonstrict_map =
+	(1U << EFX_MAE_ACTION_COUNT) |
 	(1U << EFX_MAE_ACTION_FLAG) |
 	(1U << EFX_MAE_ACTION_MARK);
 
-- 
2.20.1

Re: [dpdk-dev] [PATCH] common/sfc_efx/base: do not validate MAE action COUNT order

[Thomas Monjalon]

29/07/2021 11:32, Ivan Malov:
> In DPDK + Open vSwitch use case, action COUNT is always the
> first one to be added. In particular, it goes before action
> DECAP in that use case. The current code enforces the right
> order (DECAP goes before COUNT), and this provokes failures.
> As an exception, do not validate the order for action COUNT.
> 
> Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
> Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> Reviewed-by: Andy Moreton <amoreton@xilinx.com>

Applied, thanks