ice: Implement aRFS

Enable accelerated Receive Flow Steering (aRFS). It is used to steer Rx
flows to a specific queue. This functionality is triggered by the network
stack through ndo_rx_flow_steer and requires Flow Director (ntuple on) to
function.

The fltr_info is used to add/remove/update flow rules in the HW, the
fltr_state is used to determine what to do with the filter with respect
to HW and/or SW, and the flow_id is used in co-ordination with the
network stack.

The work for aRFS is split into two paths: the ndo_rx_flow_steer
operation and the ice_service_task. The former is where the kernel hands
us an Rx SKB among other items to setup aRFS and the latter is where
the driver adds/updates/removes filter rules from HW and updates filter
state.

In the Rx path the following things can happen:
        1. New aRFS entries are added to the hash table and the state is
           set to ICE_ARFS_INACTIVE so the filter can be updated in HW
           by the ice_service_task path.
        2. aRFS entries have their Rx Queue updated if we receive a
           pre-existing flow_id and the filter state is ICE_ARFS_ACTIVE.
           The state is set to ICE_ARFS_INACTIVE so the filter can be
           updated in HW by the ice_service_task path.
        3. aRFS entries marked as ICE_ARFS_TODEL are deleted

In the ice_service_task path the following things can happen:
        1. New aRFS entries marked as ICE_ARFS_INACTIVE are added or
           updated in HW.
           and their state is updated to ICE_ARFS_ACTIVE.
        2. aRFS entries are deleted from HW and their state is updated
           to ICE_ARFS_TODEL.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Author: bcreeley13

drivers/net/ethernet/intel/ice/Makefile

@@ -26,4 +26,5 @@ ice-y := ice_main.o	\
 	 ice_ethtool.o
 ice-$(CONFIG_PCI_IOV) += ice_virtchnl_pf.o ice_sriov.o
 ice-$(CONFIG_DCB) += ice_dcb.o ice_dcb_nl.o ice_dcb_lib.o
+ice-$(CONFIG_RFS_ACCEL) += ice_arfs.o
 ice-$(CONFIG_XDP_SOCKETS) += ice_xsk.o

drivers/net/ethernet/intel/ice/ice.h

@@ -34,6 +34,7 @@
 #include <linux/ctype.h>
 #include <linux/bpf.h>
 #include <linux/avf/virtchnl.h>
+#include <linux/cpu_rmap.h>
 #include <net/devlink.h>
 #include <net/ipv6.h>
 #include <net/xdp_sock.h>
@@ -52,6 +53,7 @@
 #include "ice_sriov.h"
 #include "ice_fdir.h"
 #include "ice_xsk.h"
+#include "ice_arfs.h"
 
 extern const char ice_drv_ver[];
 #define ICE_BAR0		0
@@ -271,6 +273,14 @@ struct ice_vsi {
 	u8 *rss_lut_user;	/* User configured lookup table entries */
 	u8 rss_lut_type;	/* used to configure Get/Set RSS LUT AQ call */
 
+	/* aRFS members only allocated for the PF VSI */
+#define ICE_MAX_ARFS_LIST	1024
+#define ICE_ARFS_LST_MASK	(ICE_MAX_ARFS_LIST - 1)
+	struct hlist_head *arfs_fltr_list;
+	struct ice_arfs_active_fltr_cntrs *arfs_fltr_cntrs;
+	spinlock_t arfs_lock;	/* protects aRFS hash table and filter state */
+	atomic_t *arfs_last_fltr_id;
+
 	u16 max_frame;
 	u16 rx_buf_len;
 
@@ -558,6 +568,9 @@ int ice_schedule_reset(struct ice_pf *pf, enum ice_reset_req reset);
 void ice_print_link_msg(struct ice_vsi *vsi, bool isup);
 const char *ice_stat_str(enum ice_status stat_err);
 const char *ice_aq_str(enum ice_aq_err aq_err);
+int
+ice_fdir_write_fltr(struct ice_pf *pf, struct ice_fdir_fltr *input, bool add,
+		    bool is_tun);
 void ice_vsi_manage_fdir(struct ice_vsi *vsi, bool ena);
 int ice_add_fdir_ethtool(struct ice_vsi *vsi, struct ethtool_rxnfc *cmd);
 int ice_del_fdir_ethtool(struct ice_vsi *vsi, struct ethtool_rxnfc *cmd);
@@ -571,5 +584,6 @@ void ice_fdir_replay_fltrs(struct ice_pf *pf);
 int ice_fdir_create_dflt_rules(struct ice_pf *pf);
 int ice_open(struct net_device *netdev);
 int ice_stop(struct net_device *netdev);
+void ice_service_task_schedule(struct ice_pf *pf);
 
 #endif /* _ICE_H_ */