[PATCH v2 0/2] Support ethtool ntuple rule count change

[PATCH v2 0/2] Support ethtool ntuple rule count change

[Sunil Goutham]

Some NICs share resources like packet filters across
multiple interfaces they support. From HW point of view
it is possible to use all filters for a single interface.
This 2 patch series adds support to modify ntuple rule
count for OcteonTx2 netdev.

Changes from v1:
   * No changes in code.
   * Previous discussion didn't conclude, submiting patches again to revive it.
   * Jakub suggested if devlink-resource can be used for this.
   * But since ntuple rule insert and delete are part of ethtool,
     I thought having this config also in ethtool makes sense ie
     all ntuple related stuff within one tool.
   * Also number of MCAM entries can be changed at runtime
     without a driver reload.

Sunil Goutham (2):
  net: ethtool: Support setting ntuple rule count
  octeontx2-pf: Support setting ntuple rule count

 .../ethernet/marvell/octeontx2/nic/otx2_common.h   |  1 +
 .../ethernet/marvell/octeontx2/nic/otx2_ethtool.c  |  3 +++
 .../ethernet/marvell/octeontx2/nic/otx2_flows.c    | 27 ++++++++++++++++++++--
 include/uapi/linux/ethtool.h                       |  1 +
 net/ethtool/ioctl.c                                |  1 +
 5 files changed, 31 insertions(+), 2 deletions(-)

-- 
2.7.4

[PATCH v2 1/2] net: ethtool: Support setting ntuple rule count

[Sunil Goutham]

Some NICs share resources like packet filters across
multiple interfaces they support. From HW point of view
it is possible to use all filters for a single interface.
Currently ethtool doesn't support modifying filter count so
that user can allocate more filters to a interface and less
to others. This patch adds ETHTOOL_SRXCLSRLCNT ioctl command
for modifying filter count.

example command:
./ethtool -U eth0 rule-count 256

Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
---
 include/uapi/linux/ethtool.h | 1 +
 net/ethtool/ioctl.c          | 1 +
 2 files changed, 2 insertions(+)

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 67aa713..178f346 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1552,6 +1552,7 @@ enum ethtool_fec_config_bits {
 #define ETHTOOL_PHY_STUNABLE	0x0000004f /* Set PHY tunable configuration */
 #define ETHTOOL_GFECPARAM	0x00000050 /* Get FEC settings */
 #define ETHTOOL_SFECPARAM	0x00000051 /* Set FEC settings */
+#define ETHTOOL_SRXCLSRLCNT	0x00000052 /* Set RX class rule count */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 6134b18..ca0f75e 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -2863,6 +2863,7 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_SRXFH:
 	case ETHTOOL_SRXCLSRLDEL:
 	case ETHTOOL_SRXCLSRLINS:
+	case ETHTOOL_SRXCLSRLCNT:
 		rc = ethtool_set_rxnfc(dev, ethcmd, useraddr);
 		break;
 	case ETHTOOL_FLASHDEV:
-- 
2.7.4

[PATCH v2 2/2] octeontx2-pf: Support setting ntuple rule count

[Sunil Goutham]

Added support for changing ethtool ntuple filter count.
Rule count change is supported only when there are no
ntuple filters installed.

Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
---
 .../ethernet/marvell/octeontx2/nic/otx2_common.h   |  1 +
 .../ethernet/marvell/octeontx2/nic/otx2_ethtool.c  |  3 +++
 .../ethernet/marvell/octeontx2/nic/otx2_flows.c    | 27 ++++++++++++++++++++--
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
index 8fd58cd..6fe2bf7 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
@@ -825,6 +825,7 @@ int otx2_get_all_flows(struct otx2_nic *pfvf,
 int otx2_add_flow(struct otx2_nic *pfvf,
 		  struct ethtool_rxnfc *nfc);
 int otx2_remove_flow(struct otx2_nic *pfvf, u32 location);
+int otx2_set_flow_rule_count(struct otx2_nic *pfvf, int count);
 int otx2_prepare_flow_request(struct ethtool_rx_flow_spec *fsp,
 			      struct npc_install_flow_req *req);
 void otx2_rss_ctx_flow_del(struct otx2_nic *pfvf, int ctx_id);
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
index 8df748e..753a8cf 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
@@ -690,6 +690,9 @@ static int otx2_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *nfc)
 		if (netif_running(dev) && ntuple)
 			ret = otx2_remove_flow(pfvf, nfc->fs.location);
 		break;
+	case ETHTOOL_SRXCLSRLCNT:
+		ret = otx2_set_flow_rule_count(pfvf, nfc->rule_cnt);
+		break;
 	default:
 		break;
 	}
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
index 4d9de52..ea2626c 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
@@ -123,12 +123,29 @@ static int otx2_alloc_ntuple_mcam_entries(struct otx2_nic *pfvf, u16 count)
 
 	if (allocated != count)
 		netdev_info(pfvf->netdev,
-			    "Unable to allocate %d MCAM entries for ntuple, got %d\n",
-			    count, allocated);
+			    "Unable to allocate %d MCAM entries above default rules' "
+			    "start index %d, got only %d\n",
+			    count, flow_cfg->def_ent[0], allocated);
 
 	return allocated;
 }
 
+int otx2_set_flow_rule_count(struct otx2_nic *pfvf, int count)
+{
+	struct otx2_flow_config *flow_cfg = pfvf->flow_cfg;
+
+	if (!flow_cfg)
+		return 0;
+
+	if (flow_cfg->nr_flows) {
+		netdev_err(pfvf->netdev,
+			   "Cannot change count when there are active rules\n");
+		return 0;
+	}
+
+	return otx2_alloc_ntuple_mcam_entries(pfvf, count);
+}
+
 int otx2_alloc_mcam_entries(struct otx2_nic *pfvf)
 {
 	struct otx2_flow_config *flow_cfg = pfvf->flow_cfg;
@@ -923,6 +940,12 @@ int otx2_add_flow(struct otx2_nic *pfvf, struct ethtool_rxnfc *nfc)
 	int err = 0;
 	u32 ring;
 
+	if (!flow_cfg->ntuple_max_flows) {
+		netdev_err(pfvf->netdev,
+			   "Ntuple rule count is 0, allocate and retry\n");
+		return -EINVAL;
+	}
+
 	ring = ethtool_get_flow_spec_ring(fsp->ring_cookie);
 	if (!(pfvf->flags & OTX2_FLAG_NTUPLE_SUPPORT))
 		return -ENOMEM;
-- 
2.7.4

Re: [PATCH v2 1/2] net: ethtool: Support setting ntuple rule count

[Andrew Lunn]

On Fri, Jul 23, 2021 at 11:46:45PM +0530, Sunil Goutham wrote:
> Some NICs share resources like packet filters across
> multiple interfaces they support. From HW point of view
> it is possible to use all filters for a single interface.
> Currently ethtool doesn't support modifying filter count so
> that user can allocate more filters to a interface and less
> to others. This patch adds ETHTOOL_SRXCLSRLCNT ioctl command
> for modifying filter count.
> 
> example command:
> ./ethtool -U eth0 rule-count 256

How can use see what the current usage is? How many in total you have
available?  What the current split is between the interfaces?

You say:

   * Jakub suggested if devlink-resource can be used for this.

devlink-resource provides you a standardised mechanism to answer the
questions i just asked. So i would have to agree with Jakub.

	  Andrew

Re: [PATCH v2 1/2] net: ethtool: Support setting ntuple rule count

[Saeed Mahameed]

On Sat, 2021-07-24 at 19:23 +0200, Andrew Lunn wrote:
> On Fri, Jul 23, 2021 at 11:46:45PM +0530, Sunil Goutham wrote:
> > Some NICs share resources like packet filters across
> > multiple interfaces they support. From HW point of view
> > it is possible to use all filters for a single interface.
> > Currently ethtool doesn't support modifying filter count so
> > that user can allocate more filters to a interface and less
> > to others. This patch adds ETHTOOL_SRXCLSRLCNT ioctl command
> > for modifying filter count.
> > 
> > example command:
> > ./ethtool -U eth0 rule-count 256
> 
> How can use see what the current usage is? How many in total you have
> available?  What the current split is between the interfaces?
> 

There is no point of adding this ethtool interface if the orchestration
tool already knows the "rule-count" in advance, it's just redundant to
have a user managed limiting device in ethtool.

> You say:
> 
>    * Jakub suggested if devlink-resource can be used for this.
> 
> devlink-resource provides you a standardised mechanism to answer the
> questions i just asked. So i would have to agree with Jakub.
> 

+1, devlink is your address when a single device is shared across
multiple interfaces.

>           Andrew