[next,S70,10/12] i40e: use i40e_stop_rings_no_wait to implement PORT_SUSPENDED state

Message ID 20170413084555.6962-10-alice.michael@intel.com
State Accepted
Delegated to: Jeff Kirsher
Headers show

Commit Message

Alice Michael April 13, 2017, 8:45 a.m.
From: Jacob Keller <jacob.e.keller@intel.com>

This state bit was added as a way for DCB to avoid having to wait for
the queues to disable when handling LLDP events. The logic for this was
burried deep within stop Tx and stop Rx queue code. First, let's rename
it so that it does not appear to only affect Tx when infact it modifies
both Tx and Rx flow. Second we can move it up into the i40e_stop_rings()
function, and we can simply re-use the i40e_stop_rings_no_wait() so that
we don't have to bury the implementation as deep into the call stack.

An alternative might be to remove the state bit and instead attempt to
shut down everything directly in DCP flow. This, however, is not ideal
because it creates yet another separate shutdown routine that we'd have
to maintain. In the current implementation any changes will be made to
both flows.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Change-ID: I68e1ccb901af320862bca395e9c9746f08e8b17c
---
 drivers/net/ethernet/intel/i40e/i40e.h      |  2 +-
 drivers/net/ethernet/intel/i40e/i40e_main.c | 16 ++++++----------
 2 files changed, 7 insertions(+), 11 deletions(-)

Comments

Shannon Nelson April 14, 2017, 7:21 p.m. | #1
On 4/13/2017 1:45 AM, Alice Michael wrote:
> From: Jacob Keller <jacob.e.keller@intel.com>
>
> This state bit was added as a way for DCB to avoid having to wait for
> the queues to disable when handling LLDP events. The logic for this was
> burried deep within stop Tx and stop Rx queue code. First, let's rename

s/burried/buried/

> it so that it does not appear to only affect Tx when infact it modifies

s/infact/in fact/

> both Tx and Rx flow. Second we can move it up into the i40e_stop_rings()
> function, and we can simply re-use the i40e_stop_rings_no_wait() so that
> we don't have to bury the implementation as deep into the call stack.
>
> An alternative might be to remove the state bit and instead attempt to
> shut down everything directly in DCP flow. This, however, is not ideal
> because it creates yet another separate shutdown routine that we'd have
> to maintain. In the current implementation any changes will be made to
> both flows.
>
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> Change-ID: I68e1ccb901af320862bca395e9c9746f08e8b17c
> ---
>  drivers/net/ethernet/intel/i40e/i40e.h      |  2 +-
>  drivers/net/ethernet/intel/i40e/i40e_main.c | 16 ++++++----------
>  2 files changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
> index d35fec3..76bc404 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e.h
> +++ b/drivers/net/ethernet/intel/i40e/i40e.h
> @@ -149,7 +149,7 @@ enum i40e_state_t {
>  	__I40E_DOWN_REQUESTED,
>  	__I40E_FD_FLUSH_REQUESTED,
>  	__I40E_RESET_FAILED,
> -	__I40E_PORT_TX_SUSPENDED,
> +	__I40E_PORT_SUSPENDED,
>  	__I40E_VF_DISABLE,
>  };
>
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
> index 7ceb256..b9d7798 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_main.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
> @@ -4008,10 +4008,6 @@ static int i40e_vsi_control_tx(struct i40e_vsi *vsi, bool enable)
>  	for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
>  		i40e_control_tx_q(pf, pf_q, enable);
>
> -		/* Don't wait to disable when port Tx is suspended */
> -		if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
> -			continue;
> -
>  		/* wait for the change to finish */
>  		ret = i40e_pf_txq_wait(pf, pf_q, enable);
>  		if (ret) {
> @@ -4105,10 +4101,6 @@ static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
>  	for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
>  		i40e_control_rx_q(pf, pf_q, enable);
>
> -		/* Don't wait to disable when port Tx is suspended */
> -		if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
> -			continue;
> -
>  		/* wait for the change to finish */
>  		ret = i40e_pf_rxq_wait(pf, pf_q, enable);
>  		if (ret) {
> @@ -4151,6 +4143,10 @@ int i40e_vsi_start_rings(struct i40e_vsi *vsi)
>   **/
>  void i40e_vsi_stop_rings(struct i40e_vsi *vsi)
>  {
> +	/* When port TX is suspended, don't wait */
> +	if (test_bit(__I40E_PORT_SUSPENDED, &vsi->back->state))
> +		return i40e_vsi_stop_rings_no_wait(vsi);
> +
>  	/* do rx first for enable and last for disable
>  	 * Ignore return value, we need to shutdown whatever we can
>  	 */
> @@ -5986,7 +5982,7 @@ static int i40e_handle_lldp_event(struct i40e_pf *pf,
>  	else
>  		pf->flags &= ~I40E_FLAG_DCB_ENABLED;
>
> -	set_bit(__I40E_PORT_TX_SUSPENDED, &pf->state);
> +	set_bit(__I40E_PORT_SUSPENDED, &pf->state);
>  	/* Reconfiguration needed quiesce all VSIs */
>  	i40e_pf_quiesce_all_vsi(pf);
>
> @@ -5995,7 +5991,7 @@ static int i40e_handle_lldp_event(struct i40e_pf *pf,
>
>  	ret = i40e_resume_port_tx(pf);
>
> -	clear_bit(__I40E_PORT_TX_SUSPENDED, &pf->state);
> +	clear_bit(__I40E_PORT_SUSPENDED, &pf->state);
>  	/* In case of error no point in resuming VSIs */
>  	if (ret)
>  		goto exit;
>
Bowers, AndrewX April 17, 2017, 5:32 p.m. | #2
> -----Original Message-----
> From: Intel-wired-lan [mailto:intel-wired-lan-bounces@lists.osuosl.org] On
> Behalf Of Alice Michael
> Sent: Thursday, April 13, 2017 1:46 AM
> To: Michael, Alice <alice.michael@intel.com>; intel-wired-
> lan@lists.osuosl.org
> Subject: [Intel-wired-lan] [next PATCH S70 10/12] i40e: use
> i40e_stop_rings_no_wait to implement PORT_SUSPENDED state
> 
> From: Jacob Keller <jacob.e.keller@intel.com>
> 
> This state bit was added as a way for DCB to avoid having to wait for the
> queues to disable when handling LLDP events. The logic for this was burried
> deep within stop Tx and stop Rx queue code. First, let's rename it so that it
> does not appear to only affect Tx when infact it modifies both Tx and Rx flow.
> Second we can move it up into the i40e_stop_rings() function, and we can
> simply re-use the i40e_stop_rings_no_wait() so that we don't have to bury
> the implementation as deep into the call stack.
> 
> An alternative might be to remove the state bit and instead attempt to shut
> down everything directly in DCP flow. This, however, is not ideal because it
> creates yet another separate shutdown routine that we'd have to maintain.
> In the current implementation any changes will be made to both flows.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> Change-ID: I68e1ccb901af320862bca395e9c9746f08e8b17c
> ---
>  drivers/net/ethernet/intel/i40e/i40e.h      |  2 +-
>  drivers/net/ethernet/intel/i40e/i40e_main.c | 16 ++++++----------
>  2 files changed, 7 insertions(+), 11 deletions(-)

Tested-by: Andrew Bowers <andrewx.bowers@intel.com>

Patch

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index d35fec3..76bc404 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -149,7 +149,7 @@  enum i40e_state_t {
 	__I40E_DOWN_REQUESTED,
 	__I40E_FD_FLUSH_REQUESTED,
 	__I40E_RESET_FAILED,
-	__I40E_PORT_TX_SUSPENDED,
+	__I40E_PORT_SUSPENDED,
 	__I40E_VF_DISABLE,
 };
 
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 7ceb256..b9d7798 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4008,10 +4008,6 @@  static int i40e_vsi_control_tx(struct i40e_vsi *vsi, bool enable)
 	for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
 		i40e_control_tx_q(pf, pf_q, enable);
 
-		/* Don't wait to disable when port Tx is suspended */
-		if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
-			continue;
-
 		/* wait for the change to finish */
 		ret = i40e_pf_txq_wait(pf, pf_q, enable);
 		if (ret) {
@@ -4105,10 +4101,6 @@  static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
 	for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
 		i40e_control_rx_q(pf, pf_q, enable);
 
-		/* Don't wait to disable when port Tx is suspended */
-		if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
-			continue;
-
 		/* wait for the change to finish */
 		ret = i40e_pf_rxq_wait(pf, pf_q, enable);
 		if (ret) {
@@ -4151,6 +4143,10 @@  int i40e_vsi_start_rings(struct i40e_vsi *vsi)
  **/
 void i40e_vsi_stop_rings(struct i40e_vsi *vsi)
 {
+	/* When port TX is suspended, don't wait */
+	if (test_bit(__I40E_PORT_SUSPENDED, &vsi->back->state))
+		return i40e_vsi_stop_rings_no_wait(vsi);
+
 	/* do rx first for enable and last for disable
 	 * Ignore return value, we need to shutdown whatever we can
 	 */
@@ -5986,7 +5982,7 @@  static int i40e_handle_lldp_event(struct i40e_pf *pf,
 	else
 		pf->flags &= ~I40E_FLAG_DCB_ENABLED;
 
-	set_bit(__I40E_PORT_TX_SUSPENDED, &pf->state);
+	set_bit(__I40E_PORT_SUSPENDED, &pf->state);
 	/* Reconfiguration needed quiesce all VSIs */
 	i40e_pf_quiesce_all_vsi(pf);
 
@@ -5995,7 +5991,7 @@  static int i40e_handle_lldp_event(struct i40e_pf *pf,
 
 	ret = i40e_resume_port_tx(pf);
 
-	clear_bit(__I40E_PORT_TX_SUSPENDED, &pf->state);
+	clear_bit(__I40E_PORT_SUSPENDED, &pf->state);
 	/* In case of error no point in resuming VSIs */
 	if (ret)
 		goto exit;