Multicore support for vCGN

    Locks are used while populating DB, which is once
    once per entry. Therefore, it is not in the performance
    critical path. Each thread is a PMD, therefore, spin locks
    are used instead of mutexes.

Change-Id: I4bc297f73a8f3eafebed1f00e51ec75ca24163f6
Signed-off-by: Shesha Sreenivasamurthy <shesha@cisco.com>

1 files changed, 91 insertions, 5 deletions

diff --git a/vnet/vnet/vcgn/cnat_db_v2.c b/vnet/vnet/vcgn/cnat_db_v2.c
index 5a26fd99d6c..2b43849dca3 100644
--- a/vnet/vnet/vcgn/cnat_db_v2.c
+++ b/vnet/vnet/vcgn/cnat_db_v2.c
@@ -43,6 +43,12 @@
 u8 cnat_db_init_done = 0;
 
 typedef struct {
+  /* Locks for multi thread support */
+  CLIB_CACHE_LINE_ALIGN_MARK(cacheline0);
+  pthread_spinlock_t *main_db_lockp;
+  pthread_spinlock_t *user_db_lockp;
+  pthread_spinlock_t *session_db_lockp;
+
   u32 cached_next_index;
   /* $$$$ add data here */
 
@@ -543,6 +549,7 @@ void cnat_user_db_delete (cnat_user_db_entry_t *up)
         return;
     }
 
+    pthread_spin_lock(cnat_db_v2_main.user_db_lockp);
 #if 1
     if(PREDICT_FALSE(up->flags & CNAT_USER_DB_DSLITE_FLAG)) {
         dslite_key_t dk = {
@@ -589,6 +596,7 @@ void cnat_user_db_delete (cnat_user_db_entry_t *up)
 
  found:
     pool_put(cnat_user_db, up);    
+    pthread_spin_unlock(cnat_db_v2_main.user_db_lockp);
 }
 
 cnat_user_db_entry_t*
@@ -622,6 +630,7 @@ cnat_user_db_create_entry(cnat_db_key_bucket_t *uki,
 {
     cnat_user_db_entry_t *udb = NULL;
 
+    pthread_spin_lock(cnat_db_v2_main.user_db_lockp);
     pool_get(cnat_user_db, udb);
     memset(udb, 0, sizeof(*udb));
 
@@ -636,6 +645,7 @@ cnat_user_db_create_entry(cnat_db_key_bucket_t *uki,
 #ifndef NO_BULK_LOGGING
     INIT_BULK_CACHE(udb)
 #endif /* NO_BULK_LOGGING */
+    pthread_spin_unlock(cnat_db_v2_main.user_db_lockp);
     return udb;
 }
 
@@ -773,6 +783,7 @@ void cnat_delete_main_db_entry_v2 (cnat_main_db_entry_t *ep)
         return;
     }
 
+   pthread_spin_lock(cnat_db_v2_main.main_db_lockp);
    if(PREDICT_FALSE(ep->flags & 
         CNAT_DB_FLAG_PPTP_TUNNEL_ACTIVE)) {
       pptp_clear_all_channels(ep);
@@ -815,7 +826,7 @@ void cnat_delete_main_db_entry_v2 (cnat_main_db_entry_t *ep)
 #endif
         spp_printf(CNAT_INV_UNUSED_USR_INDEX, 1, (u32 *) &(ep->user_index));
         cnat_main_db_entry_dump(ep);
-        return;
+        goto unlock;
     }
 
     up = cnat_user_db + ep->user_index;
@@ -922,7 +933,9 @@ delete_entry:
 
     main_db_index = ep - cnat_main_db;
 
+    pthread_spin_lock(cnat_db_v2_main.user_db_lockp);
     up->ntranslations--;
+    pthread_spin_unlock(cnat_db_v2_main.user_db_lockp);
 
     /*
      * when user reaches max allowed port limit
@@ -975,6 +988,8 @@ delete_entry:
     }
     nat44_dslite_common_stats[instance].active_translations--;
     nat44_dslite_global_stats[!!(instance - 1)].translation_delete_count ++;
+unlock:
+    pthread_spin_unlock(cnat_db_v2_main.main_db_lockp);
 }
 
 cnat_main_db_entry_t*
@@ -1098,8 +1113,8 @@ void cnat_add_dest_n_log(
  * if reash per user port limit, 
  * set user_db_entry pointer, and error == CNAT_OUT_LIMIT
  */
-cnat_main_db_entry_t*
-cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
+static cnat_main_db_entry_t*
+_cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
                           port_pair_t port_pair_type,
                           port_type_t port_type,
                           cnat_gen_icmp_info *info,
@@ -1368,7 +1383,9 @@ cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
         /*
          * increment port in use for this user
          */
+        pthread_spin_lock(cnat_db_v2_main.user_db_lockp);
         udb->ntranslations += 1;
+        pthread_spin_unlock(cnat_db_v2_main.user_db_lockp);
 	
     } else {
         /*
@@ -1592,7 +1609,9 @@ cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
        db2->vrfmap_index = my_vrfmap - cnat_map_by_vrf;
        db2->entry_expires = cnat_current_time;
        db2->flags |= CNAT_DB_FLAG_ALG_ENTRY;
+       pthread_spin_lock(cnat_db_v2_main.user_db_lockp);
        udb->ntranslations += 1;
+       pthread_spin_unlock(cnat_db_v2_main.user_db_lockp);
        db2->dst_ipv4 = dest_info->k.ipv4;
        db2->dst_port = dest_info->k.port;
        db2->nsessions = 0; /* For ALG db, set sessions to 0 - CSCuf78420 */
@@ -1624,6 +1643,22 @@ cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
     return db;
 }
 
+cnat_main_db_entry_t*
+cnat_get_main_db_entry_v2(cnat_db_key_bucket_t *ki,
+                          port_pair_t port_pair_type,
+                          port_type_t port_type,
+                          cnat_gen_icmp_info *info,
+                          cnat_key_t *dest_info)
+{
+
+    cnat_main_db_entry_t *db;
+    pthread_spin_lock(cnat_db_v2_main.main_db_lockp);
+    db = _cnat_get_main_db_entry_v2(ki, port_pair_type,
+        port_type, info, dest_info);
+    pthread_spin_unlock(cnat_db_v2_main.main_db_lockp);
+    return db;
+}
+
 /*
  * this function is called from config handler only
  * to allocate a static port based db entry
@@ -1650,6 +1685,9 @@ cnat_create_static_main_db_entry_v2 (cnat_db_key_bucket_t *ki,
     int                 nfv9_log_req = BULK_ALLOC_NOT_ATTEMPTED;
 #endif
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     /* 
      * need to try lookup again because 
      * second pkt may come here before the entry is created
@@ -1984,6 +2022,8 @@ dslite_create_static_main_db_entry_v2 (dslite_db_key_bucket_t *ki,
     cnat_vrfmap_t       *my_vrfmap =0;
     u16                 my_vrfmap_index;    
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
     /* 
      * need to try lookup again because 
      * second pkt may come here before the entry is created
@@ -2416,6 +2456,9 @@ cnat_timeout_db_create (cnat_timeout_t t_entry)
     pool_header_t        *h;
     u32                  free;
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     db_index = cnat_timeout_db_hash_lookup(t_key);
 
     if(db_index != EMPTY) {
@@ -2457,6 +2500,9 @@ void cnat_timeout_db_delete(cnat_key_t t_key)
     u32 index, bucket;
     cnat_timeout_db_entry_t *this, *prev;
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     key.k.ipv4 = t_key.k.ipv4;
     key.k.port = t_key.k.port;
     key.k.vrf = t_key.k.vrf;
@@ -2629,6 +2675,7 @@ cnat_create_session_db_entry(cnat_key_t *ko,
         return NULL;
     }
 
+    pthread_spin_lock(cnat_db_v2_main.session_db_lockp);
     pool_get(cnat_session_db, db);
     memset(db, 0, sizeof(*db));
 
@@ -2688,6 +2735,7 @@ cnat_create_session_db_entry(cnat_key_t *ko,
        newly established sessions */
     db->entry_expires = cnat_current_time;
     nat44_dslite_common_stats[instance].sessions++;
+    pthread_spin_unlock(cnat_db_v2_main.session_db_lockp);
     return db;
 }
 
@@ -2739,7 +2787,8 @@ cnat_dest_update_session2main(cnat_main_db_entry_t *mdb,
     mdb->dst_port = sdb->v4_dest_key.k.port;
 }
 
-void cnat_delete_session_db_entry (cnat_session_entry_t *ep, u8 log)
+static void
+_cnat_delete_session_db_entry (cnat_session_entry_t *ep, u8 log)
 {
     u32  session_db_index;
     u32  bdb_len;
@@ -2807,7 +2856,7 @@ void cnat_delete_session_db_entry (cnat_session_entry_t *ep, u8 log)
         ASSERT(sdb_last != NULL);
 
         cnat_dest_update_session2main(be, sdb_last);
-        cnat_delete_session_db_entry(sdb_last, FALSE);
+        _cnat_delete_session_db_entry(sdb_last, FALSE);
     }
 
     /* Remove from session DB hashes */
@@ -2817,6 +2866,13 @@ void cnat_delete_session_db_entry (cnat_session_entry_t *ep, u8 log)
     pool_put(cnat_session_db, ep);
 }
 
+void cnat_delete_session_db_entry (cnat_session_entry_t *ep, u8 log)
+{
+    pthread_spin_lock(cnat_db_v2_main.session_db_lockp);
+    _cnat_delete_session_db_entry (ep, log);
+    pthread_spin_unlock(cnat_db_v2_main.session_db_lockp);
+}
+
 cnat_main_db_entry_t*
 dslite_main_db_lookup_entry(dslite_db_key_bucket_t *ki)
 {
@@ -2899,6 +2955,9 @@ dslite_user_db_create_entry(dslite_db_key_bucket_t *uki,
 {
     cnat_user_db_entry_t *udb = NULL;
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     pool_get(cnat_user_db, udb);
     memset(udb, 0, sizeof(*udb));
 
@@ -2943,6 +3002,9 @@ dslite_create_main_db_entry_and_hash(dslite_db_key_bucket_t *ki,
     u32 db_index;
     cnat_main_db_entry_t *db = NULL;
 
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     pool_get(cnat_main_db, db);
     memset(db, 0, sizeof(*db));
 
@@ -3086,6 +3148,10 @@ dslite_get_main_db_entry_v2(dslite_db_key_bucket_t *ki,
 #ifndef NO_BULK_LOGGING
     int nfv9_log_req = BULK_ALLOC_NOT_ATTEMPTED;
 #endif
+
+    /* UNUSED. Therefore not ported to be multi-thread friendly */
+    ASSERT(0);
+
     /* 
      * need to try lookup again because 
      * second pkt may come here before the entry is created
@@ -3709,6 +3775,26 @@ void cnat_db_v2_init (void)
         svi_params_array[i].svi_type = CGSE_SVI_TYPE_INFRA;
     }
 #endif
+
+    cnat_db_v2_main.main_db_lockp =
+        clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
+            CLIB_CACHE_LINE_BYTES);
+
+    cnat_db_v2_main.user_db_lockp =
+        clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
+            CLIB_CACHE_LINE_BYTES);
+
+    cnat_db_v2_main.session_db_lockp =
+        clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
+            CLIB_CACHE_LINE_BYTES);
+
+    ASSERT (pthread_spin_init(cnat_db_v2_main.main_db_lockp,
+        PTHREAD_PROCESS_PRIVATE) == 0);
+    ASSERT (pthread_spin_init(cnat_db_v2_main.user_db_lockp,
+        PTHREAD_PROCESS_PRIVATE) == 0);
+    ASSERT (pthread_spin_init(cnat_db_v2_main.session_db_lockp,
+        PTHREAD_PROCESS_PRIVATE) == 0);
+
     cnat_db_init_done = 1;
     printf("CNAT DB init is successful\n");
     return;