bnxt_en: query cfa flow stats periodically to compute 'lastused' attribute
authorSathya Perla <sathya.perla@broadcom.com>
Thu, 26 Oct 2017 15:51:31 +0000 (11:51 -0400)
committerDavid S. Miller <davem@davemloft.net>
Fri, 27 Oct 2017 15:02:45 +0000 (00:02 +0900)
This patch implements periodic querying of cfa flow stats
in batches to compute the 'lastused' attribute of TC flow stats.

Signed-off-by: Sathya Perla <sathya.perla@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/broadcom/bnxt/bnxt.c
drivers/net/ethernet/broadcom/bnxt/bnxt.h
drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c
drivers/net/ethernet/broadcom/bnxt/bnxt_tc.h

index c767291..bbf6da3 100644 (file)
@@ -6979,6 +6979,11 @@ static void bnxt_timer(unsigned long data)
                set_bit(BNXT_PERIODIC_STATS_SP_EVENT, &bp->sp_event);
                bnxt_queue_sp_work(bp);
        }
+
+       if (bnxt_tc_flower_enabled(bp)) {
+               set_bit(BNXT_FLOW_STATS_SP_EVENT, &bp->sp_event);
+               bnxt_queue_sp_work(bp);
+       }
 bnxt_restart_timer:
        mod_timer(&bp->timer, jiffies + bp->current_interval);
 }
@@ -7069,6 +7074,10 @@ static void bnxt_sp_task(struct work_struct *work)
                bnxt_get_port_module_status(bp);
                mutex_unlock(&bp->link_lock);
        }
+
+       if (test_and_clear_bit(BNXT_FLOW_STATS_SP_EVENT, &bp->sp_event))
+               bnxt_tc_flow_stats_work(bp);
+
        /* These functions below will clear BNXT_STATE_IN_SP_TASK.  They
         * must be the last functions to be called before exiting.
         */
index d88d864..b8343ee 100644 (file)
@@ -955,6 +955,11 @@ struct bnxt_coal {
        u8                      budget;
 };
 
+struct bnxt_tc_flow_stats {
+       u64             packets;
+       u64             bytes;
+};
+
 struct bnxt_tc_info {
        bool                            enabled;
 
@@ -980,6 +985,14 @@ struct bnxt_tc_info {
         */
        struct mutex                    lock;
 
+       /* Fields used for batching stats query */
+       struct rhashtable_iter          iter;
+#define BNXT_FLOW_STATS_BATCH_MAX      10
+       struct bnxt_tc_stats_batch {
+               void                      *flow_node;
+               struct bnxt_tc_flow_stats hw_stats;
+       } stats_batch[BNXT_FLOW_STATS_BATCH_MAX];
+
        /* Stat counter mask (width) */
        u64                             bytes_mask;
        u64                             packets_mask;
@@ -1282,6 +1295,7 @@ struct bnxt {
 #define BNXT_GENEVE_ADD_PORT_SP_EVENT  12
 #define BNXT_GENEVE_DEL_PORT_SP_EVENT  13
 #define BNXT_LINK_SPEED_CHNG_SP_EVENT  14
+#define BNXT_FLOW_STATS_SP_EVENT       15
 
        struct bnxt_pf_info     pf;
 #ifdef CONFIG_BNXT_SRIOV
index 0d258d3..71828a5 100644 (file)
@@ -504,81 +504,6 @@ static int bnxt_hwrm_cfa_flow_alloc(struct bnxt *bp, struct bnxt_tc_flow *flow,
        return rc;
 }
 
-/* Add val to accum while handling a possible wraparound
- * of val. Eventhough val is of type u64, its actual width
- * is denoted by mask and will wrap-around beyond that width.
- */
-static void accumulate_val(u64 *accum, u64 val, u64 mask)
-{
-#define low_bits(x, mask)              ((x) & (mask))
-#define high_bits(x, mask)             ((x) & ~(mask))
-       bool wrapped = val < low_bits(*accum, mask);
-
-       *accum = high_bits(*accum, mask) + val;
-       if (wrapped)
-               *accum += (mask + 1);
-}
-
-/* The HW counters' width is much less than 64bits.
- * Handle possible wrap-around while updating the stat counters
- */
-static void bnxt_flow_stats_fix_wraparound(struct bnxt_tc_info *tc_info,
-                                          struct bnxt_tc_flow_stats *stats,
-                                          struct bnxt_tc_flow_stats *hw_stats)
-{
-       accumulate_val(&stats->bytes, hw_stats->bytes, tc_info->bytes_mask);
-       accumulate_val(&stats->packets, hw_stats->packets,
-                      tc_info->packets_mask);
-}
-
-/* Fix possible wraparound of the stats queried from HW, calculate
- * the delta from prev_stats, and also update the prev_stats.
- * The HW flow stats are fetched under the hwrm_cmd_lock mutex.
- * This routine is best called while under the mutex so that the
- * stats processing happens atomically.
- */
-static void bnxt_flow_stats_calc(struct bnxt_tc_info *tc_info,
-                                struct bnxt_tc_flow *flow,
-                                struct bnxt_tc_flow_stats *stats)
-{
-       struct bnxt_tc_flow_stats *acc_stats, *prev_stats;
-
-       acc_stats = &flow->stats;
-       bnxt_flow_stats_fix_wraparound(tc_info, acc_stats, stats);
-
-       prev_stats = &flow->prev_stats;
-       stats->bytes = acc_stats->bytes - prev_stats->bytes;
-       stats->packets = acc_stats->packets - prev_stats->packets;
-       *prev_stats = *acc_stats;
-}
-
-static int bnxt_hwrm_cfa_flow_stats_get(struct bnxt *bp,
-                                       __le16 flow_handle,
-                                       struct bnxt_tc_flow *flow,
-                                       struct bnxt_tc_flow_stats *stats)
-{
-       struct hwrm_cfa_flow_stats_output *resp = bp->hwrm_cmd_resp_addr;
-       struct hwrm_cfa_flow_stats_input req = { 0 };
-       int rc;
-
-       bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_CFA_FLOW_STATS, -1, -1);
-       req.num_flows = cpu_to_le16(1);
-       req.flow_handle_0 = flow_handle;
-
-       mutex_lock(&bp->hwrm_cmd_lock);
-       rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
-       if (!rc) {
-               stats->packets = le64_to_cpu(resp->packet_0);
-               stats->bytes = le64_to_cpu(resp->byte_0);
-               bnxt_flow_stats_calc(&bp->tc_info, flow, stats);
-       } else {
-               netdev_info(bp->dev, "error rc=%d", rc);
-       }
-
-       mutex_unlock(&bp->hwrm_cmd_lock);
-       return rc;
-}
-
 static int hwrm_cfa_decap_filter_alloc(struct bnxt *bp,
                                       struct bnxt_tc_flow *flow,
                                       struct bnxt_tc_l2_key *l2_info,
@@ -1306,6 +1231,8 @@ static int bnxt_tc_add_flow(struct bnxt *bp, u16 src_fid,
        if (rc)
                goto put_tunnel;
 
+       flow->lastused = jiffies;
+       spin_lock_init(&flow->stats_lock);
        /* add new flow to flow-table */
        rc = rhashtable_insert_fast(&tc_info->flow_table, &new_node->node,
                                    tc_info->flow_ht_params);
@@ -1352,10 +1279,11 @@ static int bnxt_tc_del_flow(struct bnxt *bp,
 static int bnxt_tc_get_flow_stats(struct bnxt *bp,
                                  struct tc_cls_flower_offload *tc_flow_cmd)
 {
+       struct bnxt_tc_flow_stats stats, *curr_stats, *prev_stats;
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        struct bnxt_tc_flow_node *flow_node;
-       struct bnxt_tc_flow_stats stats;
-       int rc;
+       struct bnxt_tc_flow *flow;
+       unsigned long lastused;
 
        flow_node = rhashtable_lookup_fast(&tc_info->flow_table,
                                           &tc_flow_cmd->cookie,
@@ -1366,15 +1294,183 @@ static int bnxt_tc_get_flow_stats(struct bnxt *bp,
                return -1;
        }
 
-       rc = bnxt_hwrm_cfa_flow_stats_get(bp, flow_node->flow_handle,
-                                         &flow_node->flow, &stats);
+       flow = &flow_node->flow;
+       curr_stats = &flow->stats;
+       prev_stats = &flow->prev_stats;
+
+       spin_lock(&flow->stats_lock);
+       stats.packets = curr_stats->packets - prev_stats->packets;
+       stats.bytes = curr_stats->bytes - prev_stats->bytes;
+       *prev_stats = *curr_stats;
+       lastused = flow->lastused;
+       spin_unlock(&flow->stats_lock);
+
+       tcf_exts_stats_update(tc_flow_cmd->exts, stats.bytes, stats.packets,
+                             lastused);
+       return 0;
+}
+
+static int
+bnxt_hwrm_cfa_flow_stats_get(struct bnxt *bp, int num_flows,
+                            struct bnxt_tc_stats_batch stats_batch[])
+{
+       struct hwrm_cfa_flow_stats_output *resp = bp->hwrm_cmd_resp_addr;
+       struct hwrm_cfa_flow_stats_input req = { 0 };
+       __le16 *req_flow_handles = &req.flow_handle_0;
+       int rc, i;
+
+       bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_CFA_FLOW_STATS, -1, -1);
+       req.num_flows = cpu_to_le16(num_flows);
+       for (i = 0; i < num_flows; i++) {
+               struct bnxt_tc_flow_node *flow_node = stats_batch[i].flow_node;
+
+               req_flow_handles[i] = flow_node->flow_handle;
+       }
+
+       mutex_lock(&bp->hwrm_cmd_lock);
+       rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+       if (!rc) {
+               __le64 *resp_packets = &resp->packet_0;
+               __le64 *resp_bytes = &resp->byte_0;
+
+               for (i = 0; i < num_flows; i++) {
+                       stats_batch[i].hw_stats.packets =
+                                               le64_to_cpu(resp_packets[i]);
+                       stats_batch[i].hw_stats.bytes =
+                                               le64_to_cpu(resp_bytes[i]);
+               }
+       } else {
+               netdev_info(bp->dev, "error rc=%d", rc);
+       }
+
+       mutex_unlock(&bp->hwrm_cmd_lock);
+       return rc;
+}
+
+/* Add val to accum while handling a possible wraparound
+ * of val. Eventhough val is of type u64, its actual width
+ * is denoted by mask and will wrap-around beyond that width.
+ */
+static void accumulate_val(u64 *accum, u64 val, u64 mask)
+{
+#define low_bits(x, mask)              ((x) & (mask))
+#define high_bits(x, mask)             ((x) & ~(mask))
+       bool wrapped = val < low_bits(*accum, mask);
+
+       *accum = high_bits(*accum, mask) + val;
+       if (wrapped)
+               *accum += (mask + 1);
+}
+
+/* The HW counters' width is much less than 64bits.
+ * Handle possible wrap-around while updating the stat counters
+ */
+static void bnxt_flow_stats_accum(struct bnxt_tc_info *tc_info,
+                                 struct bnxt_tc_flow_stats *acc_stats,
+                                 struct bnxt_tc_flow_stats *hw_stats)
+{
+       accumulate_val(&acc_stats->bytes, hw_stats->bytes, tc_info->bytes_mask);
+       accumulate_val(&acc_stats->packets, hw_stats->packets,
+                      tc_info->packets_mask);
+}
+
+static int
+bnxt_tc_flow_stats_batch_update(struct bnxt *bp, int num_flows,
+                               struct bnxt_tc_stats_batch stats_batch[])
+{
+       struct bnxt_tc_info *tc_info = &bp->tc_info;
+       int rc, i;
+
+       rc = bnxt_hwrm_cfa_flow_stats_get(bp, num_flows, stats_batch);
        if (rc)
                return rc;
 
-       tcf_exts_stats_update(tc_flow_cmd->exts, stats.bytes, stats.packets, 0);
+       for (i = 0; i < num_flows; i++) {
+               struct bnxt_tc_flow_node *flow_node = stats_batch[i].flow_node;
+               struct bnxt_tc_flow *flow = &flow_node->flow;
+
+               spin_lock(&flow->stats_lock);
+               bnxt_flow_stats_accum(tc_info, &flow->stats,
+                                     &stats_batch[i].hw_stats);
+               if (flow->stats.packets != flow->prev_stats.packets)
+                       flow->lastused = jiffies;
+               spin_unlock(&flow->stats_lock);
+       }
+
        return 0;
 }
 
+static int
+bnxt_tc_flow_stats_batch_prep(struct bnxt *bp,
+                             struct bnxt_tc_stats_batch stats_batch[],
+                             int *num_flows)
+{
+       struct bnxt_tc_info *tc_info = &bp->tc_info;
+       struct rhashtable_iter *iter = &tc_info->iter;
+       void *flow_node;
+       int rc, i;
+
+       rc = rhashtable_walk_start(iter);
+       if (rc && rc != -EAGAIN) {
+               i = 0;
+               goto done;
+       }
+
+       rc = 0;
+       for (i = 0; i < BNXT_FLOW_STATS_BATCH_MAX; i++) {
+               flow_node = rhashtable_walk_next(iter);
+               if (IS_ERR(flow_node)) {
+                       i = 0;
+                       if (PTR_ERR(flow_node) == -EAGAIN) {
+                               continue;
+                       } else {
+                               rc = PTR_ERR(flow_node);
+                               goto done;
+                       }
+               }
+
+               /* No more flows */
+               if (!flow_node)
+                       goto done;
+
+               stats_batch[i].flow_node = flow_node;
+       }
+done:
+       rhashtable_walk_stop(iter);
+       *num_flows = i;
+       return rc;
+}
+
+void bnxt_tc_flow_stats_work(struct bnxt *bp)
+{
+       struct bnxt_tc_info *tc_info = &bp->tc_info;
+       int num_flows, rc;
+
+       num_flows = atomic_read(&tc_info->flow_table.nelems);
+       if (!num_flows)
+               return;
+
+       rhashtable_walk_enter(&tc_info->flow_table, &tc_info->iter);
+
+       for (;;) {
+               rc = bnxt_tc_flow_stats_batch_prep(bp, tc_info->stats_batch,
+                                                  &num_flows);
+               if (rc) {
+                       if (rc == -EAGAIN)
+                               continue;
+                       break;
+               }
+
+               if (!num_flows)
+                       break;
+
+               bnxt_tc_flow_stats_batch_update(bp, num_flows,
+                                               tc_info->stats_batch);
+       }
+
+       rhashtable_walk_exit(&tc_info->iter);
+}
+
 int bnxt_tc_setup_flower(struct bnxt *bp, u16 src_fid,
                         struct tc_cls_flower_offload *cls_flower)
 {
index 2beccd4..404f98d 100644 (file)
@@ -78,11 +78,6 @@ struct bnxt_tc_actions {
        struct ip_tunnel_key            tun_encap_key;
 };
 
-struct bnxt_tc_flow_stats {
-       u64             packets;
-       u64             bytes;
-};
-
 struct bnxt_tc_flow {
        u32                             flags;
 #define BNXT_TC_FLOW_FLAGS_ETH_ADDRS           BIT(1)
@@ -119,6 +114,10 @@ struct bnxt_tc_flow {
        /* previous snap-shot of stats */
        struct bnxt_tc_flow_stats       prev_stats;
        unsigned long                   lastused; /* jiffies */
+       /* for calculating delta from prev_stats and
+        * updating prev_stats atomically.
+        */
+       spinlock_t                      stats_lock;
 };
 
 /* Tunnel encap/decap hash table
@@ -195,6 +194,12 @@ int bnxt_tc_setup_flower(struct bnxt *bp, u16 src_fid,
                         struct tc_cls_flower_offload *cls_flower);
 int bnxt_init_tc(struct bnxt *bp);
 void bnxt_shutdown_tc(struct bnxt *bp);
+void bnxt_tc_flow_stats_work(struct bnxt *bp);
+
+static inline bool bnxt_tc_flower_enabled(struct bnxt *bp)
+{
+       return bp->tc_info.enabled;
+}
 
 #else /* CONFIG_BNXT_FLOWER_OFFLOAD */
 
@@ -212,5 +217,14 @@ static inline int bnxt_init_tc(struct bnxt *bp)
 static inline void bnxt_shutdown_tc(struct bnxt *bp)
 {
 }
+
+static inline void bnxt_tc_flow_stats_work(struct bnxt *bp)
+{
+}
+
+static inline bool bnxt_tc_flower_enabled(struct bnxt *bp)
+{
+       return false;
+}
 #endif /* CONFIG_BNXT_FLOWER_OFFLOAD */
 #endif /* BNXT_TC_H */