OS-4018 lxbrand support TCP SO_REUSEPORT
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Cody Mello <cody.mello@joyent.com>

*** 404,413 ****
--- 404,429 ----
          uint32_t        tlc_cnt;
          int64_t         tlc_report_time;
          uint32_t        tlc_drop;
  } tcp_listen_cnt_t;
  
+ /*
+  * Track tcp_t entities bound to the same port/address tuple via SO_REUSEPORT.
+  * - tcprg_lock:        Protects the other fields
+  * - tcprg_size:        Allocated size (in entries) of tcprg_members array
+  * - tcprg_count:       Count of occupied tcprg_members slots
+  * - tcprg_active:      Count of members which still have SO_REUSEPORT set
+  * - tcprg_members:     Connections associated with address/port group
+  */
+ typedef struct tcp_rg_s {
+         kmutex_t        tcprg_lock;
+         unsigned int    tcprg_size;
+         unsigned int    tcprg_count;
+         unsigned int    tcprg_active;
+         tcp_t           **tcprg_members;
+ } tcp_rg_t;
+ 
  #define TCP_TLC_REPORT_INTERVAL (30 * MINUTES)
  
  #define TCP_DECR_LISTEN_CNT(tcp)                                        \
  {                                                                       \
          ASSERT((tcp)->tcp_listen_cnt->tlc_cnt > 0);                     \
*** 647,656 ****
--- 663,676 ----
  extern void     tcp_bind_hash_remove(tcp_t *);
  extern in_port_t        tcp_bindi(tcp_t *, in_port_t, const in6_addr_t *,
                              int, boolean_t, boolean_t, boolean_t);
  extern in_port_t        tcp_update_next_port(in_port_t, const tcp_t *,
                              boolean_t);
+ extern tcp_rg_t *tcp_rg_init(tcp_t *);
+ extern boolean_t tcp_rg_remove(tcp_rg_t *, tcp_t *);
+ extern void tcp_rg_destroy(tcp_rg_t *);
+ extern void tcp_rg_setactive(tcp_rg_t *, boolean_t);
  
  /*
   * Fusion related functions in tcp_fusion.c.
   */
  extern void     tcp_fuse(tcp_t *, uchar_t *, tcpha_t *);