Merge branch 'rickard/barriers/OTP-9281' into dev

* rickard/barriers/OTP-9281:
  Silence warnings
  Fix build with hipe on amd64
  Reduce number of atomic ops
  Use 32-bit atomic for port snapshot
  Remove pointless erts_ports_alive variable
  Ensure quick break
  Ensure that all rehashing information are seen when done
  Ensure that stack updates are seen when stack is released
  Add needed barriers for write_concurrency tables
  Homogenize memory barriers on atomics

1 files changed, 4 insertions, 5 deletions

diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 30b0a60611..499bdd77ba 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -183,7 +183,7 @@ struct port {
 				    process to get (line oriented I/O)*/
     Uint32 status;		 /* Status and type flags */
     int control_flags;		 /* Flags for port_control()  */
-    Uint32 snapshot;             /* Next snapshot that port should be part of */
+    erts_aint32_t snapshot;      /* Next snapshot that port should be part of */
     struct reg_proc *reg;
     ErlDrvPDL port_data_lock;
 
@@ -527,11 +527,10 @@ union erl_off_heap_ptr {
 
 /* arrays that get malloced at startup */
 extern Port* erts_port;
-extern erts_smp_atomic_t erts_ports_alive;
 
 extern Uint erts_max_ports;
 extern Uint erts_port_tab_index_mask;
-extern erts_smp_atomic_t erts_ports_snapshot;
+extern erts_smp_atomic32_t erts_ports_snapshot;
 extern erts_smp_atomic_t erts_dead_ports_ptr;
 
 ERTS_GLB_INLINE void erts_may_save_closed_port(Port *prt);
@@ -541,12 +540,12 @@ ERTS_GLB_INLINE void erts_may_save_closed_port(Port *prt);
 ERTS_GLB_INLINE void erts_may_save_closed_port(Port *prt)
 {
     ERTS_SMP_LC_ASSERT(erts_smp_lc_spinlock_is_locked(&prt->state_lck));
-    if (prt->snapshot != erts_smp_atomic_read(&erts_ports_snapshot)) {
+    if (prt->snapshot != erts_smp_atomic32_read_acqb(&erts_ports_snapshot)) {
 	/* Dead ports are added from the end of the snapshot buffer */
 	Eterm* tombstone = (Eterm*) erts_smp_atomic_addtest(&erts_dead_ports_ptr,
 							    -(erts_aint_t)sizeof(Eterm));
 	ASSERT(tombstone+1 != NULL);
-	ASSERT(prt->snapshot == (Uint32) erts_smp_atomic_read(&erts_ports_snapshot) - 1);
+	ASSERT(prt->snapshot == erts_smp_atomic32_read(&erts_ports_snapshot) - 1);
 	*tombstone = prt->id;
     }
     /*else no ongoing snapshot or port was already included or created after snapshot */