Replace system block with thread progress block

The ERTS internal system block functionality has been replaced by
new functionality for blocking the system. The old system block
functionality had contention issues and complexity issues. The
new functionality piggy-backs on thread progress tracking functionality
needed by newly introduced lock-free synchronization in the runtime
system. When the functionality for blocking the system isn't used
there is more or less no overhead at all. This since the functionality
for tracking thread progress is there and needed anyway.

1 files changed, 0 insertions, 277 deletions

diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index 9f5747205d..b63fe98f27 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -702,283 +702,6 @@ typedef struct {
 
 void sys_alloc_stat(SysAllocStat *);
 
-/* Block the whole system... */
-
-#define ERTS_BS_FLG_ALLOW_GC				(((Uint32) 1) << 0)
-#define ERTS_BS_FLG_ALLOW_IO				(((Uint32) 1) << 1)
-
-/* Activities... */
-typedef enum {
-    ERTS_ACTIVITY_UNDEFINED,	/* Undefined activity */
-    ERTS_ACTIVITY_WAIT,		/* Waiting */
-    ERTS_ACTIVITY_GC,		/* Garbage collecting */
-    ERTS_ACTIVITY_IO		/* I/O including message passing to erl procs */
-} erts_activity_t;
-
-#ifdef ERTS_SMP
-
-typedef enum {
-    ERTS_ACT_ERR_LEAVE_WAIT_UNLOCKED,
-    ERTS_ACT_ERR_LEAVE_UNKNOWN_ACTIVITY,
-    ERTS_ACT_ERR_ENTER_UNKNOWN_ACTIVITY
-} erts_activity_error_t;
-
-typedef struct {
-    erts_smp_atomic32_t do_block;
-    struct {
-	erts_smp_atomic32_t wait;
-	erts_smp_atomic32_t gc;
-	erts_smp_atomic32_t io;
-    } in_activity;
-} erts_system_block_state_t;
-
-extern erts_system_block_state_t erts_system_block_state;
-
-int erts_is_system_blocked(erts_activity_t allowed_activities);
-void erts_block_me(void (*prepare)(void *), void (*resume)(void *), void *arg);
-void erts_register_blockable_thread(void);
-void erts_unregister_blockable_thread(void);
-void erts_note_activity_begin(erts_activity_t activity);
-void
-erts_check_block(erts_activity_t old_activity,
-		 erts_activity_t new_activity,
-		 int locked,
-		 void (*prepare)(void *),
-		 void (*resume)(void *),
-		 void *arg);
-void erts_block_system(Uint32 allowed_activities);
-int erts_emergency_block_system(long timeout, Uint32 allowed_activities);
-void erts_release_system(void);
-void erts_system_block_init(void);
-void erts_set_activity_error(erts_activity_error_t, char *, int);
-#ifdef ERTS_ENABLE_LOCK_CHECK
-void erts_lc_activity_change_begin(void);
-void erts_lc_activity_change_end(void);
-int erts_lc_is_blocking(void);
-#define ERTS_LC_IS_BLOCKING \
-  (erts_smp_pending_system_block() && erts_lc_is_blocking())
-#endif
-#endif
-
-#define erts_smp_activity_begin(NACT, PRP, RSM, ARG)		\
-  erts_smp_set_activity(ERTS_ACTIVITY_UNDEFINED,		\
-			(NACT),					\
-			0,					\
-			(PRP),					\
-			(RSM),					\
-			(ARG),					\
-			__FILE__,				\
-			__LINE__)
-#define erts_smp_activity_change(OACT, NACT, PRP, RSM, ARG)	\
-  erts_smp_set_activity((OACT),					\
-			(NACT),					\
-			0,					\
-			(PRP),					\
-			(RSM),					\
-			(ARG),					\
-			__FILE__,				\
-			__LINE__)
-#define erts_smp_activity_end(OACT, PRP, RSM, ARG)		\
-  erts_smp_set_activity((OACT),					\
-			ERTS_ACTIVITY_UNDEFINED,		\
-			0,					\
-			(PRP),					\
-			(RSM),					\
-			(ARG),					\
-			__FILE__,				\
-			__LINE__)
-
-#define erts_smp_locked_activity_begin(NACT)			\
-  erts_smp_set_activity(ERTS_ACTIVITY_UNDEFINED,		\
-			(NACT),					\
-			1,					\
-			NULL,					\
-			NULL,					\
-			NULL,					\
-			__FILE__,				\
-			__LINE__)
-#define erts_smp_locked_activity_change(OACT, NACT)		\
-  erts_smp_set_activity((OACT),					\
-			(NACT),					\
-			1,					\
-			NULL,					\
-			NULL,					\
-			NULL,					\
-			__FILE__,				\
-			__LINE__)
-#define erts_smp_locked_activity_end(OACT)			\
-  erts_smp_set_activity((OACT),					\
-			ERTS_ACTIVITY_UNDEFINED,		\
-			1,					\
-			NULL,					\
-			NULL,					\
-			NULL,					\
-			__FILE__,				\
-			__LINE__)
-
-
-ERTS_GLB_INLINE int erts_smp_is_system_blocked(erts_activity_t allowed_activities);
-ERTS_GLB_INLINE void erts_smp_block_system(Uint32 allowed_activities);
-ERTS_GLB_INLINE int erts_smp_emergency_block_system(long timeout,
-						    Uint32 allowed_activities);
-ERTS_GLB_INLINE void erts_smp_release_system(void);
-ERTS_GLB_INLINE int erts_smp_pending_system_block(void);
-ERTS_GLB_INLINE void erts_smp_chk_system_block(void (*prepare)(void *),
-					       void (*resume)(void *),
-					       void *arg);
-ERTS_GLB_INLINE void
-erts_smp_set_activity(erts_activity_t old_activity,
-		      erts_activity_t new_activity,
-		      int locked,
-		      void (*prepare)(void *),
-		      void (*resume)(void *),
-		      void *arg,
-		      char *file,
-		      int line);
-
-#if ERTS_GLB_INLINE_INCL_FUNC_DEF
-
-
-ERTS_GLB_INLINE int
-erts_smp_is_system_blocked(erts_activity_t allowed_activities)
-{
-#ifdef ERTS_SMP
-    return erts_is_system_blocked(allowed_activities);
-#else
-    return 1;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_block_system(Uint32 allowed_activities)
-{
-#ifdef ERTS_SMP
-    erts_block_system(allowed_activities);
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_emergency_block_system(long timeout, Uint32 allowed_activities)
-{
-#ifdef ERTS_SMP
-    return erts_emergency_block_system(timeout, allowed_activities);
-#else
-    return 0;
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_release_system(void)
-{
-#ifdef ERTS_SMP
-    erts_release_system();
-#endif
-}
-
-ERTS_GLB_INLINE int
-erts_smp_pending_system_block(void)
-{
-#ifdef ERTS_SMP
-    return (int) erts_smp_atomic32_read_nob(&erts_system_block_state.do_block);
-#else
-    return 0;
-#endif
-}
-
-
-ERTS_GLB_INLINE void
-erts_smp_chk_system_block(void (*prepare)(void *),
-			  void (*resume)(void *),
-			  void *arg)
-{
-#ifdef ERTS_SMP
-    if (erts_smp_pending_system_block())
-	erts_block_me(prepare, resume, arg);
-#endif
-}
-
-ERTS_GLB_INLINE void
-erts_smp_set_activity(erts_activity_t old_activity,
-		      erts_activity_t new_activity,
-		      int locked,
-		      void (*prepare)(void *),
-		      void (*resume)(void *),
-		      void *arg,
-		      char *file,
-		      int line)
-{
-#ifdef ERTS_SMP
-#ifdef ERTS_ENABLE_LOCK_CHECK
-    erts_lc_activity_change_begin();
-#endif
-    switch (old_activity) {
-    case ERTS_ACTIVITY_UNDEFINED:
-	break;
-    case ERTS_ACTIVITY_WAIT:
-	erts_smp_atomic32_dec_acqb(&erts_system_block_state.in_activity.wait);
-	if (locked) {
-	    /* You are not allowed to leave activity waiting
-	     * without supplying the possibility to block
-	     * unlocked.
-	     */
-	    erts_set_activity_error(ERTS_ACT_ERR_LEAVE_WAIT_UNLOCKED,
-				    file, line);
-	}
-	break;
-    case ERTS_ACTIVITY_GC:
-	erts_smp_atomic32_dec_acqb(&erts_system_block_state.in_activity.gc);
-	break;
-    case ERTS_ACTIVITY_IO:
-	erts_smp_atomic32_dec_acqb(&erts_system_block_state.in_activity.io);
-	break;
-    default:
-	erts_set_activity_error(ERTS_ACT_ERR_LEAVE_UNKNOWN_ACTIVITY,
-				file, line);
-	break;
-    }
-
-    /* We are not allowed to block when going to activity waiting... */
-    if (new_activity != ERTS_ACTIVITY_WAIT && erts_smp_pending_system_block())
-	erts_check_block(old_activity,new_activity,locked,prepare,resume,arg);
-
-    switch (new_activity) {
-    case ERTS_ACTIVITY_UNDEFINED:
-	break;
-    case ERTS_ACTIVITY_WAIT:
-	erts_smp_atomic32_inc_mb(&erts_system_block_state.in_activity.wait);
-	break;
-    case ERTS_ACTIVITY_GC:
-	erts_smp_atomic32_inc_mb(&erts_system_block_state.in_activity.gc);
-	break;
-    case ERTS_ACTIVITY_IO:
-	erts_smp_atomic32_inc_mb(&erts_system_block_state.in_activity.io);
-	break;
-    default:
-	erts_set_activity_error(ERTS_ACT_ERR_ENTER_UNKNOWN_ACTIVITY,
-				file, line);
-	break;
-    }
-
-    switch (new_activity) {
-    case ERTS_ACTIVITY_WAIT:
-    case ERTS_ACTIVITY_GC:
-    case ERTS_ACTIVITY_IO:
-	if (erts_smp_pending_system_block())
-	    erts_note_activity_begin(new_activity);
-	break;
-    default:
-	break;
-    }
-
-#ifdef ERTS_ENABLE_LOCK_CHECK
-    erts_lc_activity_change_end();
-#endif
-
-#endif
-}
-
-#endif /* #if ERTS_GLB_INLINE_INCL_FUNC_DEF */
-
 #if defined(DEBUG) || defined(ERTS_ENABLE_LOCK_CHECK)
 #undef ERTS_REFC_DEBUG
 #define ERTS_REFC_DEBUG