session: update fifo slice on session migration

Type: fix

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: Ic5fb0f95c58ad70925a365004fe911ac8f2d2382

5 files changed, 150 insertions, 24 deletions

diff --git a/src/svm/fifo_segment.c b/src/svm/fifo_segment.c
index eb240b0ada1..cfc795418b2 100644
--- a/src/svm/fifo_segment.c
+++ b/src/svm/fifo_segment.c
@@ -657,7 +657,7 @@ fs_try_alloc_fifo (fifo_segment_header_t * fsh, fifo_segment_slice_t * fss,
       ssvm_pop_heap (oldheap);
       if (f)
 	{
-	  fss->num_chunks[fl_index] += 1;
+	  clib_atomic_fetch_add_rel (&fss->num_chunks[fl_index], 1);
 	  fsh_free_bytes_sub (fsh, fifo_sz);
 	  goto done;
 	}
@@ -717,7 +717,7 @@ fsh_alloc_chunk (fifo_segment_header_t * fsh, u32 slice_index, u32 chunk_size)
 
 	  if (c)
 	    {
-	      fss->num_chunks[fl_index] += 1;
+	      clib_atomic_fetch_add_rel (&fss->num_chunks[fl_index], 1);
 	      fsh_free_bytes_sub (fsh, chunk_size + sizeof (*c));
 	      goto done;
 	    }
@@ -796,6 +796,31 @@ fsh_collect_chunks (fifo_segment_header_t * fsh, u32 slice_index,
   fsh_slice_collect_chunks (fsh, fss, c);
 }
 
+static inline void
+fss_fifo_add_active_list (fifo_segment_slice_t * fss, svm_fifo_t * f)
+{
+  if (fss->fifos)
+    {
+      fss->fifos->prev = f;
+      f->next = fss->fifos;
+    }
+  fss->fifos = f;
+}
+
+static inline void
+fss_fifo_del_active_list (fifo_segment_slice_t * fss, svm_fifo_t * f)
+{
+  if (f->flags & SVM_FIFO_F_LL_TRACKED)
+    {
+      if (f->prev)
+	f->prev->next = f->next;
+      else
+	fss->fifos = f->next;
+      if (f->next)
+	f->next->prev = f->prev;
+    }
+}
+
 /**
  * Allocate fifo in fifo segment
  */
@@ -824,12 +849,7 @@ fifo_segment_alloc_fifo_w_slice (fifo_segment_t * fs, u32 slice_index,
    * only one. */
   if (ftype == FIFO_SEGMENT_RX_FIFO)
     {
-      if (fss->fifos)
-	{
-	  fss->fifos->prev = f;
-	  f->next = fss->fifos;
-	}
-      fss->fifos = f;
+      fss_fifo_add_active_list (fss, f);
       f->flags |= SVM_FIFO_F_LL_TRACKED;
 
       svm_fifo_init_ooo_lookup (f, 0 /* ooo enq */ );
@@ -865,12 +885,7 @@ fifo_segment_free_fifo (fifo_segment_t * fs, svm_fifo_t * f)
   /* Remove from active list. Only rx fifos are tracked */
   if (f->flags & SVM_FIFO_F_LL_TRACKED)
     {
-      if (f->prev)
-	f->prev->next = f->next;
-      else
-	fss->fifos = f->next;
-      if (f->next)
-	f->next->prev = f->prev;
+      fss_fifo_del_active_list (fss, f);
       f->flags &= ~SVM_FIFO_F_LL_TRACKED;
     }
 
@@ -900,6 +915,52 @@ fifo_segment_free_fifo (fifo_segment_t * fs, svm_fifo_t * f)
   fsh_active_fifos_update (fsh, -1);
 }
 
+void
+fifo_segment_detach_fifo (fifo_segment_t * fs, svm_fifo_t * f)
+{
+  fifo_segment_slice_t *fss;
+  svm_fifo_chunk_t *c;
+  u32 fl_index;
+
+  ASSERT (f->refcnt == 1);
+
+  fss = fsh_slice_get (fs->h, f->slice_index);
+  fss->virtual_mem -= svm_fifo_size (f);
+  if (f->flags & SVM_FIFO_F_LL_TRACKED)
+    fss_fifo_del_active_list (fss, f);
+
+  c = f->start_chunk;
+  while (c)
+    {
+      fl_index = fs_freelist_for_size (c->length);
+      clib_atomic_fetch_sub_rel (&fss->num_chunks[fl_index], 1);
+      c = c->next;
+    }
+}
+
+void
+fifo_segment_attach_fifo (fifo_segment_t * fs, svm_fifo_t * f,
+			  u32 slice_index)
+{
+  fifo_segment_slice_t *fss;
+  svm_fifo_chunk_t *c;
+  u32 fl_index;
+
+  f->slice_index = slice_index;
+  fss = fsh_slice_get (fs->h, f->slice_index);
+  fss->virtual_mem += svm_fifo_size (f);
+  if (f->flags & SVM_FIFO_F_LL_TRACKED)
+    fss_fifo_add_active_list (fss, f);
+
+  c = f->start_chunk;
+  while (c)
+    {
+      fl_index = fs_freelist_for_size (c->length);
+      clib_atomic_fetch_add_rel (&fss->num_chunks[fl_index], 1);
+      c = c->next;
+    }
+}
+
 int
 fifo_segment_prealloc_fifo_hdrs (fifo_segment_t * fs, u32 slice_index,
 				 u32 batch_size)
diff --git a/src/svm/fifo_segment.h b/src/svm/fifo_segment.h
index 2e193029e85..ee5c24d04bb 100644
--- a/src/svm/fifo_segment.h
+++ b/src/svm/fifo_segment.h
@@ -120,6 +120,10 @@ svm_fifo_t *fifo_segment_alloc_fifo_w_slice (fifo_segment_t * fs,
  */
 void fifo_segment_free_fifo (fifo_segment_t * fs, svm_fifo_t * f);
 
+void fifo_segment_detach_fifo (fifo_segment_t * fs, svm_fifo_t * f);
+void fifo_segment_attach_fifo (fifo_segment_t * fs, svm_fifo_t * f,
+			       u32 slice_index);
+
 /**
  * Try to preallocate fifo headers
  *
diff --git a/src/vnet/session/segment_manager.c b/src/vnet/session/segment_manager.c
index 716f2a39a4e..b40675ad56f 100644
--- a/src/vnet/session/segment_manager.c
+++ b/src/vnet/session/segment_manager.c
@@ -743,6 +743,30 @@ segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo, svm_fifo_t * tx_fifo)
     segment_manager_segment_reader_unlock (sm);
 }
 
+void
+segment_manager_detach_fifo (segment_manager_t * sm, svm_fifo_t * f)
+{
+  fifo_segment_t *fs;
+
+  fs = segment_manager_get_segment_w_lock (sm, f->segment_index);
+  fifo_segment_detach_fifo (fs, f);
+  segment_manager_segment_reader_unlock (sm);
+}
+
+void
+segment_manager_attach_fifo (segment_manager_t * sm, svm_fifo_t * f,
+			     session_t * s)
+{
+  fifo_segment_t *fs;
+
+  fs = segment_manager_get_segment_w_lock (sm, f->segment_index);
+  fifo_segment_attach_fifo (fs, f, s->thread_index);
+  segment_manager_segment_reader_unlock (sm);
+
+  f->master_session_index = s->session_index;
+  f->master_thread_index = s->thread_index;
+}
+
 u32
 segment_manager_evt_q_expected_size (u32 q_len)
 {
diff --git a/src/vnet/session/segment_manager.h b/src/vnet/session/segment_manager.h
index cd02d5480ae..13b1fffa1e2 100644
--- a/src/vnet/session/segment_manager.h
+++ b/src/vnet/session/segment_manager.h
@@ -125,6 +125,9 @@ int segment_manager_try_alloc_fifos (fifo_segment_t * fs,
 				     svm_fifo_t ** tx_fifo);
 void segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo,
 				    svm_fifo_t * tx_fifo);
+void segment_manager_detach_fifo (segment_manager_t * sm, svm_fifo_t * f);
+void segment_manager_attach_fifo (segment_manager_t * sm, svm_fifo_t * f,
+				  session_t * s);
 
 void segment_manager_set_watermarks (segment_manager_t * sm,
 				     u8 high_watermark, u8 low_watermark);
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 9d531240f27..1fa787217f3 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -809,6 +809,31 @@ session_ho_stream_connect_notify (transport_connection_t * tc,
   return session_stream_connect_notify_inline (tc, err, SESSION_STATE_OPENED);
 }
 
+static void
+session_switch_pool_reply (void *arg)
+{
+  u32 session_index = pointer_to_uword (arg);
+  segment_manager_t *sm;
+  app_worker_t *app_wrk;
+  session_t *s;
+
+  s = session_get_if_valid (session_index, vlib_get_thread_index ());
+  if (!s)
+    return;
+
+  app_wrk = app_worker_get_if_valid (s->app_wrk_index);
+  if (!app_wrk)
+    return;
+
+  /* Attach fifos to the right session and segment slice */
+  sm = app_worker_get_connect_segment_manager (app_wrk);
+  segment_manager_attach_fifo (sm, s->rx_fifo, s);
+  segment_manager_attach_fifo (sm, s->tx_fifo, s);
+
+  /* Notify app that it has data on the new session */
+  session_enqueue_notify (s);
+}
+
 typedef struct _session_switch_pool_args
 {
   u32 session_index;
@@ -824,28 +849,38 @@ static void
 session_switch_pool (void *cb_args)
 {
   session_switch_pool_args_t *args = (session_switch_pool_args_t *) cb_args;
+  session_handle_t new_sh;
+  segment_manager_t *sm;
   app_worker_t *app_wrk;
   session_t *s;
+  void *rargs;
 
   ASSERT (args->thread_index == vlib_get_thread_index ());
   s = session_get (args->session_index, args->thread_index);
-  s->tx_fifo->master_session_index = args->new_session_index;
-  s->tx_fifo->master_thread_index = args->new_thread_index;
+
   transport_cleanup (session_get_transport_proto (s), s->connection_index,
 		     s->thread_index);
 
+  new_sh = session_make_handle (args->new_session_index,
+				args->new_thread_index);
+
   app_wrk = app_worker_get_if_valid (s->app_wrk_index);
   if (app_wrk)
     {
-      session_handle_t new_sh;
-      new_sh = session_make_handle (args->new_session_index,
-				    args->new_thread_index);
-      app_worker_migrate_notify (app_wrk, s, new_sh);
+      /* Cleanup fifo segment slice state for fifos */
+      sm = app_worker_get_connect_segment_manager (app_wrk);
+      segment_manager_detach_fifo (sm, s->rx_fifo);
+      segment_manager_detach_fifo (sm, s->tx_fifo);
 
-      /* Trigger app read on the new thread */
-      session_enqueue_notify_thread (new_sh);
+      /* Notify app, using old session, about the migration event */
+      app_worker_migrate_notify (app_wrk, s, new_sh);
     }
 
+  /* Trigger app read and fifo updates on the new thread */
+  rargs = uword_to_pointer (args->new_session_index, void *);
+  session_send_rpc_evt_to_thread (args->new_thread_index,
+				  session_switch_pool_reply, rargs);
+
   session_free (s);
   clib_mem_free (cb_args);
 }
@@ -865,10 +900,9 @@ session_dgram_connect_notify (transport_connection_t * tc,
    */
   new_s = session_clone_safe (tc->s_index, old_thread_index);
   new_s->connection_index = tc->c_index;
-  new_s->rx_fifo->master_session_index = new_s->session_index;
-  new_s->rx_fifo->master_thread_index = new_s->thread_index;
   new_s->session_state = SESSION_STATE_READY;
   new_s->flags |= SESSION_F_IS_MIGRATING;
+
   session_lookup_add_connection (tc, session_handle (new_s));
 
   /*