Add DTrace support for OS X, Solaris, and Linux (via SystemTap), 3/4

Add probes to the virtual machine, except (mostly) the efile_drv.c
driver and other file I/O-related source files.

19 files changed, 1459 insertions, 7 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index c65b2be106..d0beccfda2 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -42,6 +42,9 @@
 #include "hipe_bif1.h"
 #endif
 
+#include <assert.h>
+#include "dtrace-wrapper.h"
+
 /* #define HARDDEBUG 1 */
 
 #if defined(NO_JUMP_TABLE)
@@ -1050,6 +1053,143 @@ init_emulator(void)
 #  define REG_tmp_arg2
 #endif
 
+ERTS_INLINE void
+dtrace_proc_str(Process *process, char *process_buf)
+{
+    dtrace_pid_str(process->id, process_buf);
+}
+
+ERTS_INLINE void
+dtrace_pid_str(Eterm pid, char *process_buf)
+{
+    snprintf(process_buf, DTRACE_TERM_BUF_SIZE, "<%lu.%lu.%lu>",
+             pid_channel_no(pid),
+             pid_number(pid),
+             pid_serial(pid));
+}
+
+ERTS_INLINE void
+dtrace_port_str(Port *port, char *port_buf)
+{
+    snprintf(port_buf, DTRACE_TERM_BUF_SIZE, "#Port<%lu.%lu>",
+             port_channel_no(port->id),
+             port_number(port->id));
+}
+
+ERTS_INLINE void
+dtrace_drvport_str(ErlDrvPort drvport, char *port_buf)
+{
+    Port *port = erts_drvport2port(drvport);
+
+    snprintf(port_buf, DTRACE_TERM_BUF_SIZE, "#Port<%lu.%lu>",
+             port_channel_no(port->id),
+             port_number(port->id));
+}
+
+ERTS_INLINE void
+dtrace_fun_decode(Process *process,
+                  Eterm module, Eterm function, int arity,
+                  char *process_buf, char *mfa_buf)
+{
+    char funbuf[DTRACE_TERM_BUF_SIZE];
+    char *funptr = funbuf;
+    char *p = NULL;
+
+    if (process_buf) {
+        dtrace_proc_str(process, process_buf);
+    }
+
+    erts_snprintf(funbuf, sizeof(funbuf), "%T", function);
+    /*
+     * I'm not quite sure how these function names are synthesized,
+     *  but they almost always seem to be in the form of
+     *  '-name/arity-fun-0-' so I'm chopping them up when it's -fun-0-
+     *  (which seems to be the toplevel)
+     */
+    if (funbuf[0] == '\'' && funbuf[1] == '-'
+        && strlen(funbuf) > 3 && funbuf[strlen(funbuf) - 3] == '0') {
+        p = strchr(funbuf, '/');
+        if (p) {
+            *p = 0;
+        }
+        funptr += 2;
+    }
+
+    erts_snprintf(mfa_buf, DTRACE_TERM_BUF_SIZE, "%T:%s/%d",
+                  module, funptr, arity);
+}
+
+#ifdef HAVE_DTRACE
+
+#define DTRACE_CALL(p, m, f, a)                                 \
+    if (DTRACE_ENABLED(function_entry)) {                       \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        int depth = (STACK_START(p) - STACK_TOP(p))             \
+            / sizeof(Eterm*);                                   \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE3(function_entry, process_name, mfa, depth);      \
+    }
+
+#define DTRACE_RETURN(p, m, f, a)                               \
+    if (DTRACE_ENABLED(function_return)) {                      \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        int depth = (STACK_START(p) - STACK_TOP(p))             \
+            / sizeof(Eterm*);                                   \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE3(function_return, process_name, mfa, depth);     \
+    }
+
+#define DTRACE_BIF_ENTRY(p, m, f, a)                            \
+    if (DTRACE_ENABLED(bif_entry)) {                            \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE2(bif_entry, process_name, mfa);                  \
+    }
+
+#define DTRACE_BIF_RETURN(p, m, f, a)                           \
+    if (DTRACE_ENABLED(bif_return)) {                           \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE2(bif_return, process_name, mfa);                 \
+    }
+
+#define DTRACE_NIF_ENTRY(p, m, f, a)                            \
+    if (DTRACE_ENABLED(nif_entry)) {                            \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE2(nif_entry, process_name, mfa);                  \
+    }
+
+#define DTRACE_NIF_RETURN(p, m, f, a)                           \
+    if (DTRACE_ENABLED(nif_return)) {                           \
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);     \
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);              \
+        dtrace_fun_decode(p, m, f, a,                           \
+                          process_name, mfa);                   \
+        DTRACE2(nif_return, process_name, mfa);                 \
+    }
+
+#else /* HAVE_DTRACE */
+
+#define DTRACE_CALL(p, m, f, a)       do {} while (0)
+#define DTRACE_RETURN(p, m, f, a)     do {} while (0)
+#define DTRACE_BIF_ENTRY(p, m, f, a)  do {} while (0)
+#define DTRACE_BIF_RETURN(p, m, f, a) do {} while (0)
+#define DTRACE_NIF_ENTRY(p, m, f, a)  do {} while (0)
+#define DTRACE_NIF_RETURN(p, m, f, a) do {} while (0)
+
+#endif /* HAVE_DTRACE */
+
 /*
  * process_main() is called twice:
  * The first call performs some initialisation, including exporting
@@ -1221,6 +1361,28 @@ void process_main(void)
 #endif
 	SWAPIN;
 	ASSERT(VALID_INSTR(next));
+
+        if (DTRACE_ENABLED(process_scheduled)) {
+            DTRACE_CHARBUF(process_buf, DTRACE_TERM_BUF_SIZE);
+            DTRACE_CHARBUF(fun_buf, DTRACE_TERM_BUF_SIZE);
+            dtrace_proc_str(c_p, process_buf);
+
+            if (ERTS_PROC_IS_EXITING(c_p)) {
+                strcpy(fun_buf, "<exiting>");
+            } else {
+                BeamInstr *fptr = find_function_from_pc(c_p->i);
+                if (fptr) {
+                    dtrace_fun_decode(c_p, (Eterm)fptr[0],
+                                      (Eterm)fptr[1], (Uint)fptr[2],
+                                      NULL, fun_buf);
+                } else {
+                    snprintf(fun_buf, sizeof(fun_buf), "<unknown/%p>", next);
+                }
+            }
+
+            DTRACE2(process_scheduled, process_buf, fun_buf);
+        }
+
 	Goto(next);
     }
 
@@ -1486,7 +1648,13 @@ void process_main(void)
 
 
  OpCase(return): {
+    BeamInstr* fptr;
     SET_I(c_p->cp);
+
+    if (DTRACE_ENABLED(function_return) && (fptr = find_function_from_pc(c_p->cp))) {
+        DTRACE_RETURN(c_p, (Eterm)fptr[0], (Eterm)fptr[1], (Uint)fptr[2]);
+    }
+
     /*
      * We must clear the CP to make sure that a stale value do not
      * create a false module dependcy preventing code upgrading.
@@ -1755,6 +1923,7 @@ void process_main(void)
 	  * remove it...
 	  */
 	 ASSERT(!msgp->data.attached);
+         /* TODO: Add DTrace probe for this bad message situation? */
 	 UNLINK_MESSAGE(c_p, msgp);
 	 free_message(msgp);
 	 goto loop_rec__;
@@ -1798,6 +1967,22 @@ void process_main(void)
 	 seq_trace_output(SEQ_TRACE_TOKEN(c_p), msg, SEQ_TRACE_RECEIVE, 
 			  c_p->id, c_p);
      }
+     if (DTRACE_ENABLED(message_receive)) {
+         Eterm token2 = NIL;
+         DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
+         Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
+
+         dtrace_proc_str(c_p, receiver_name);
+         token2 = SEQ_TRACE_TOKEN(c_p);
+         if (token2 != NIL) {
+             tok_label = signed_val(SEQ_TRACE_T_LABEL(token2));
+             tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token2));
+             tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token2));
+         }
+         DTRACE6(message_receive,
+                 receiver_name, size_object(ERL_MESSAGE_TERM(msgp)),
+                 c_p->msg.len - 1, tok_label, tok_lastcnt, tok_serial);
+     }
      UNLINK_MESSAGE(c_p, msgp);
      JOIN_MESSAGE(c_p);
      CANCEL_TIMER(c_p);
@@ -3157,6 +3342,8 @@ void process_main(void)
 	     */
 	    BifFunction vbf;
 
+	    DTRACE_NIF_ENTRY(c_p, (Eterm)I[-3], (Eterm)I[-2], (Uint)I[-1]);
+
 	    c_p->current = I-3; /* current and vbf set to please handle_error */ 
 	    SWAPOUT;
 	    c_p->fcalls = FCALLS - 1;
@@ -3178,6 +3365,9 @@ void process_main(void)
 	    ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(nif_bif_result));
 	    PROCESS_MAIN_CHK_LOCKS(c_p);
 	    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+
+	    DTRACE_NIF_RETURN(c_p, (Eterm)I[-3], (Eterm)I[-2], (Uint)I[-1]);
+
 	    goto apply_bif_or_nif_epilogue;
 	 
 	OpCase(apply_bif):
@@ -3197,6 +3387,8 @@ void process_main(void)
 	    c_p->arity = 0;		/* To allow garbage collection on ourselves
 					 * (check_process_code/2).
 					 */
+	    DTRACE_BIF_ENTRY(c_p, (Eterm)I[-3], (Eterm)I[-2], (Uint)I[-1]);
+
 	    SWAPOUT;
 	    c_p->fcalls = FCALLS - 1;
 	    vbf = (BifFunction) Arg(0);
@@ -3216,6 +3408,8 @@ void process_main(void)
 		PROCESS_MAIN_CHK_LOCKS(c_p);
 	    }
 
+	    DTRACE_BIF_RETURN(c_p, (Eterm)I[-3], (Eterm)I[-2], (Uint)I[-1]);
+
 	apply_bif_or_nif_epilogue:
 	    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
 	    ERTS_HOLE_CHECK(c_p);
@@ -5899,6 +6093,13 @@ apply(Process* p, Eterm module, Eterm function, Eterm args, Eterm* reg)
 	save_calls(p, ep);
     }
 
+    if (DTRACE_ENABLED(function_entry) && ep->address) {
+        BeamInstr *fptr = find_function_from_pc(ep->address);
+        if (fptr) {
+            DTRACE_CALL(p, (Eterm)fptr[0], (Eterm)fptr[1], (Uint)fptr[2]);
+        }
+    }
+
     return ep->address;
 }
 
@@ -5948,6 +6149,13 @@ fixed_apply(Process* p, Eterm* reg, Uint arity)
 	save_calls(p, ep);
     }
 
+    if (DTRACE_ENABLED(function_entry)) {
+        BeamInstr *fptr = find_function_from_pc(ep->address);
+        if (fptr) {
+            DTRACE_CALL(p, (Eterm)fptr[0], (Eterm)fptr[1], (Uint)fptr[2]);
+        }
+    }
+
     return ep->address;
 }
 
@@ -5997,6 +6205,14 @@ erts_hibernate(Process* c_p, Eterm module, Eterm function, Eterm args, Eterm* re
 	c_p->max_arg_reg = sizeof(c_p->def_arg_reg)/sizeof(c_p->def_arg_reg[0]);
     }
 
+    if (DTRACE_ENABLED(process_hibernate)) {
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);
+        dtrace_fun_decode(c_p, module, function, arity,
+                          process_name, mfa);
+        DTRACE2(process_hibernate, process_name, mfa);
+    }
+
     /*
      * Arrange for the process to be resumed at the given MFA with
      * the stack cleared.
@@ -6071,6 +6287,14 @@ call_fun(Process* p,		/* Current process. */
 	code_ptr = fe->address;
 	actual_arity = (int) code_ptr[-1];
 
+	if (DTRACE_ENABLED(function_entry)) {
+	    BeamInstr *fptr = find_function_from_pc(code_ptr);
+
+	    if (fptr) {
+		DTRACE_CALL(p, fe->module, (Eterm)fptr[1], actual_arity);
+	    }
+	}
+
 	if (actual_arity == arity+num_free) {
 	    if (num_free == 0) {
 		return code_ptr;
@@ -6089,7 +6313,7 @@ call_fun(Process* p,		/* Current process. */
 	} else {
 	    /*
 	     * Something wrong here. First build a list of the arguments.
-	     */  
+	     */
 
 	    if (is_non_value(args)) {
 		Uint sz = 2 * arity;
@@ -6164,6 +6388,7 @@ call_fun(Process* p,		/* Current process. */
 	actual_arity = (int) ep->code[2];
 
 	if (arity == actual_arity) {
+	    DTRACE_CALL(p, ep->code[0], ep->code[1], (Uint)ep->code[2]);
 	    return ep->address;
 	} else {
 	    /*
@@ -6239,6 +6464,7 @@ call_fun(Process* p,		/* Current process. */
 	    reg[1] = function;
 	    reg[2] = args;
 	}
+	DTRACE_CALL(p, module, function, arity);
 	return ep->address;
     } else {
     badfun:
diff --git a/erts/emulator/beam/copy.c b/erts/emulator/beam/copy.c
index 1d968fb147..4ee60807d9 100644
--- a/erts/emulator/beam/copy.c
+++ b/erts/emulator/beam/copy.c
@@ -30,6 +30,7 @@
 #include "big.h"
 #include "erl_binary.h"
 #include "erl_bits.h"
+#include "dtrace-wrapper.h"
 
 #ifdef HYBRID
 MA_STACK_DECLARE(src);
@@ -59,6 +60,12 @@ copy_object(Eterm obj, Process* to)
     Eterm* hp = HAlloc(to, size);
     Eterm res;
 
+    if (DTRACE_ENABLED(copy_object)) {
+        DTRACE_CHARBUF(proc_name, 64);
+
+        erts_snprintf(proc_name, sizeof(proc_name), "%T", to->id);
+        DTRACE2(copy_object, proc_name, size);
+    }
     res = copy_struct(obj, size, &hp, &to->off_heap);
 #ifdef DEBUG
     if (eq(obj, res) == 0) {
@@ -213,6 +220,8 @@ Eterm copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
     if (IS_CONST(obj))
 	return obj;
 
+    DTRACE1(copy_struct, (int32_t)sz);
+
     hp = htop = *hpp;
     hbot   = htop + sz;
     hstart = (char *)htop;
diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index bee61e7273..6f6b04d278 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -42,6 +42,7 @@
 #include "external.h"
 #include "erl_binary.h"
 #include "erl_thr_progress.h"
+#include "dtrace-wrapper.h"
 
 /* Turn this on to get printouts of all distribution messages
  * which go on the line
@@ -740,6 +741,11 @@ erts_dsig_send_msg(ErtsDSigData *dsdp, Eterm remote, Eterm message)
     Eterm token = NIL;
     Process *sender = dsdp->proc;
     int res;
+    Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
+    Uint msize = 0;
+    DTRACE_CHARBUF(node_name, 64);
+    DTRACE_CHARBUF(sender_name, 64);
+    DTRACE_CHARBUF(receiver_name, 64);
 
     UseTmpHeapNoproc(5);
     if (SEQ_TRACE_TOKEN(sender) != NIL) {
@@ -747,12 +753,28 @@ erts_dsig_send_msg(ErtsDSigData *dsdp, Eterm remote, Eterm message)
 	token = SEQ_TRACE_TOKEN(sender);
 	seq_trace_output(token, message, SEQ_TRACE_SEND, remote, sender);
     }
+    *node_name = *sender_name = *receiver_name = '\0';
+    if (DTRACE_ENABLED(message_send) || DTRACE_ENABLED(message_send_remote)) {
+        erts_snprintf(node_name, sizeof(node_name), "%T", dsdp->dep->sysname);
+        erts_snprintf(sender_name, sizeof(sender_name), "%T", sender->id);
+        erts_snprintf(receiver_name, sizeof(receiver_name), "%T", remote);
+        msize = size_object(message);
+        if (token != NIL) {
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(token));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token));
+        }
+    }
 
     if (token != NIL)
 	ctl = TUPLE4(&ctl_heap[0],
 		     make_small(DOP_SEND_TT), am_Cookie, remote, token);
     else
 	ctl = TUPLE3(&ctl_heap[0], make_small(DOP_SEND), am_Cookie, remote);
+    DTRACE6(message_send, sender_name, receiver_name,
+            msize, tok_label, tok_lastcnt, tok_serial);
+    DTRACE7(message_send_remote, sender_name, node_name, receiver_name,
+            msize, tok_label, tok_lastcnt, tok_serial);
     res = dsig_send(dsdp, ctl, message, 0);
     UnUseTmpHeapNoproc(5);
     return res;
@@ -766,6 +788,11 @@ erts_dsig_send_reg_msg(ErtsDSigData *dsdp, Eterm remote_name, Eterm message)
     Eterm token = NIL;
     Process *sender = dsdp->proc;
     int res;
+    Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
+    Uint32 msize = 0;
+    DTRACE_CHARBUF(node_name, 64);
+    DTRACE_CHARBUF(sender_name, 64);
+    DTRACE_CHARBUF(receiver_name, 128);
 
     UseTmpHeapNoproc(6);
     if (SEQ_TRACE_TOKEN(sender) != NIL) {
@@ -773,6 +800,19 @@ erts_dsig_send_reg_msg(ErtsDSigData *dsdp, Eterm remote_name, Eterm message)
 	token = SEQ_TRACE_TOKEN(sender);
 	seq_trace_output(token, message, SEQ_TRACE_SEND, remote_name, sender);
     }
+    *node_name = *sender_name = *receiver_name = '\0';
+    if (DTRACE_ENABLED(message_send) || DTRACE_ENABLED(message_send_remote)) {
+        erts_snprintf(node_name, sizeof(node_name), "%T", dsdp->dep->sysname);
+        erts_snprintf(sender_name, sizeof(sender_name), "%T", sender->id);
+        erts_snprintf(receiver_name, sizeof(receiver_name),
+                      "{%T,%s}", remote_name, node_name);
+        msize = size_object(message);
+        if (token != NIL) {
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(token));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token));
+        }
+    }
 
     if (token != NIL)
 	ctl = TUPLE5(&ctl_heap[0], make_small(DOP_REG_SEND_TT),
@@ -780,6 +820,10 @@ erts_dsig_send_reg_msg(ErtsDSigData *dsdp, Eterm remote_name, Eterm message)
     else
 	ctl = TUPLE4(&ctl_heap[0], make_small(DOP_REG_SEND),
 		     sender->id, am_Cookie, remote_name);
+    DTRACE6(message_send, sender_name, receiver_name,
+            msize, tok_label, tok_lastcnt, tok_serial);
+    DTRACE7(message_send_remote, sender_name, node_name, receiver_name,
+            msize, tok_label, tok_lastcnt, tok_serial);
     res = dsig_send(dsdp, ctl, message, 0);
     UnUseTmpHeapNoproc(6);
     return res;
@@ -793,6 +837,12 @@ erts_dsig_send_exit_tt(ErtsDSigData *dsdp, Eterm local, Eterm remote,
     Eterm ctl;
     DeclareTmpHeapNoproc(ctl_heap,6);
     int res;
+    Process *sender = dsdp->proc;
+    Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
+    DTRACE_CHARBUF(node_name, 64);
+    DTRACE_CHARBUF(sender_name, 64);
+    DTRACE_CHARBUF(remote_name, 128);
+    DTRACE_CHARBUF(reason_str, 128);
 
     UseTmpHeapNoproc(6);
     if (token != NIL) {	
@@ -803,6 +853,21 @@ erts_dsig_send_exit_tt(ErtsDSigData *dsdp, Eterm local, Eterm remote,
     } else {
 	ctl = TUPLE4(&ctl_heap[0], make_small(DOP_EXIT), local, remote, reason);
     }
+    *node_name = *sender_name = *remote_name = '\0';
+    if (DTRACE_ENABLED(process_exit_signal_remote)) {
+        erts_snprintf(node_name, sizeof(node_name), "%T", dsdp->dep->sysname);
+        erts_snprintf(sender_name, sizeof(sender_name), "%T", sender->id);
+        erts_snprintf(remote_name, sizeof(remote_name),
+                      "{%T,%s}", remote, node_name);
+        erts_snprintf(reason_str, sizeof(reason), "%T", reason);
+        if (token != NIL) {
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(token));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token));
+        }
+    }
+    DTRACE7(process_exit_signal_remote, sender_name, node_name,
+            remote_name, reason_str, tok_label, tok_lastcnt, tok_serial);
     /* forced, i.e ignore busy */
     res = dsig_send(dsdp, ctl, THE_NON_VALUE, 1);
     UnUseTmpHeapNoproc(6);
@@ -1619,6 +1684,16 @@ dsig_send(ErtsDSigData *dsdp, Eterm ctl, Eterm msg, int force_busy)
 	    if (!(dep->qflgs & ERTS_DE_QFLG_BUSY)) {
 		if (suspended)
 		    resume = 1; /* was busy when we started, but isn't now */
+                if (resume && DTRACE_ENABLED(dist_port_not_busy)) {
+                    DTRACE_CHARBUF(port_str, 64);
+                    DTRACE_CHARBUF(remote_str, 64);
+
+                    erts_snprintf(port_str, sizeof(port_str), "%T", cid);
+                    erts_snprintf(remote_str, sizeof(remote_str),
+                                  "%T", dep->sysname);
+                    DTRACE3(dist_port_not_busy, erts_this_node_sysname,
+                            port_str, remote_str);
+                }
 	    }
 	    else {
 		/* Enqueue suspended process on dist entry */
@@ -1668,6 +1743,17 @@ dsig_send(ErtsDSigData *dsdp, Eterm ctl, Eterm msg, int force_busy)
     }
 
     if (suspended) {
+        if (!resume && DTRACE_ENABLED(dist_port_busy)) {
+            DTRACE_CHARBUF(port_str, 64);
+            DTRACE_CHARBUF(remote_str, 64);
+            DTRACE_CHARBUF(pid_str, 16);
+
+            erts_snprintf(port_str, sizeof(port_str), "%T", cid);
+            erts_snprintf(remote_str, sizeof(remote_str), "%T", dep->sysname);
+            erts_snprintf(pid_str, sizeof(pid_str), "%T", c_p->id);
+            DTRACE4(dist_port_busy, erts_this_node_sysname,
+                    port_str, remote_str, pid_str);
+        }
 	if (!resume && erts_system_monitor_flags.busy_dist_port)
 	    monitor_generic(c_p, am_busy_dist_port, cid);
 	return ERTS_DSIG_SEND_YIELD;
@@ -1691,6 +1777,16 @@ dist_port_command(Port *prt, ErtsDistOutputBuf *obuf)
 		 "(%beu bytes) passed.\n",
 		 size);
 
+    if (DTRACE_ENABLED(dist_output)) {
+        DTRACE_CHARBUF(port_str, 64);
+        DTRACE_CHARBUF(remote_str, 64);
+
+        erts_snprintf(port_str, sizeof(port_str), "%T", prt->id);
+        erts_snprintf(remote_str, sizeof(remote_str),
+                      "%T", prt->dist_entry->sysname);
+        DTRACE4(dist_output, erts_this_node_sysname, port_str,
+                remote_str, size);
+    }
     prt->caller = NIL;
     fpe_was_unmasked = erts_block_fpe();
     (*prt->drv_ptr->output)((ErlDrvData) prt->drv_data,
@@ -1733,6 +1829,16 @@ dist_port_commandv(Port *prt, ErtsDistOutputBuf *obuf)
 
     ASSERT(prt->drv_ptr->outputv);
 
+    if (DTRACE_ENABLED(dist_outputv)) {
+        DTRACE_CHARBUF(port_str, 64);
+        DTRACE_CHARBUF(remote_str, 64);
+
+        erts_snprintf(port_str, sizeof(port_str), "%T", prt->id);
+        erts_snprintf(remote_str, sizeof(remote_str),
+                      "%T", prt->dist_entry->sysname);
+        DTRACE4(dist_outputv, erts_this_node_sysname, port_str,
+                remote_str, size);
+    }
     prt->caller = NIL;
     fpe_was_unmasked = erts_block_fpe();
     (*prt->drv_ptr->outputv)((ErlDrvData) prt->drv_data, &eiov);
@@ -2052,6 +2158,16 @@ erts_dist_command(Port *prt, int reds_limit)
 void
 erts_dist_port_not_busy(Port *prt)
 {
+    if (DTRACE_ENABLED(dist_port_not_busy)) {
+        DTRACE_CHARBUF(port_str, 64);
+        DTRACE_CHARBUF(remote_str, 64);
+
+        erts_snprintf(port_str, sizeof(port_str), "%T", prt->id);
+        erts_snprintf(remote_str, sizeof(remote_str),
+                      "%T", prt->dist_entry->sysname);
+        DTRACE3(dist_port_not_busy, erts_this_node_sysname,
+                port_str, remote_str);
+    }
     erts_schedule_dist_command(prt, NULL);
 }
 
@@ -2985,6 +3101,19 @@ send_nodes_mon_msgs(Process *c_p, Eterm what, Eterm node, Eterm type, Eterm reas
     ASSERT(is_immed(what));
     ASSERT(is_immed(node));
     ASSERT(is_immed(type));
+    if (DTRACE_ENABLED(dist_monitor)) {
+        DTRACE_CHARBUF(what_str, 12);
+        DTRACE_CHARBUF(node_str, 64);
+        DTRACE_CHARBUF(type_str, 12);
+        DTRACE_CHARBUF(reason_str, 64);
+
+        erts_snprintf(what_str, sizeof(what_str), "%T", what);
+        erts_snprintf(node_str, sizeof(node_str), "%T", node);
+        erts_snprintf(type_str, sizeof(type_str), "%T", type);
+        erts_snprintf(reason_str, sizeof(reason_str), "%T", reason);
+        DTRACE5(dist_monitor, erts_this_node_sysname,
+                what_str, node_str, type_str, reason_str);
+    }
 
     ERTS_SMP_LC_ASSERT(!c_p
 		       || (erts_proc_lc_my_proc_locks(c_p)
diff --git a/erts/emulator/beam/erl_async.c b/erts/emulator/beam/erl_async.c
index 8bca9ae582..72dcc99f4f 100644
--- a/erts/emulator/beam/erl_async.c
+++ b/erts/emulator/beam/erl_async.c
@@ -26,6 +26,7 @@
 #include "erl_threads.h"
 #include "erl_thr_queue.h"
 #include "erl_async.h"
+#include "dtrace-wrapper.h"
 
 #define ERTS_MAX_ASYNC_READY_CALLS_IN_SEQ 20
 
@@ -121,6 +122,14 @@ typedef struct {
 #endif
 } ErtsAsyncData;
 
+/*
+ * Some compilers, e.g. GCC 4.2.1 and -O3, will optimize away DTrace
+ * calls if they're the last thing in the function.  :-(
+ * Many thanks to Trond Norbye, via:
+ * https://github.com/memcached/memcached/commit/6298b3978687530bc9d219b6ac707a1b681b2a46
+ */
+static unsigned gcc_optimizer_hack = 0;
+
 int erts_async_max_threads; /* Initialized by erl_init.c */
 int erts_async_thread_suggested_stack_size; /* Initialized by erl_init.c */
 
@@ -244,6 +253,9 @@ erts_get_async_ready_queue(Uint sched_id)
 
 static ERTS_INLINE void async_add(ErtsAsync *a, ErtsAsyncQ* q)
 {
+    /* DTRACE TODO: Get the queue length from erts_thr_q_enqueue() */
+    int len = -1;
+
     if (is_internal_port(a->port)) {
 #if ERTS_USE_ASYNC_READY_Q
 	ErtsAsyncReadyQ *arq = async_ready_q(a->sched_id);
@@ -259,6 +271,13 @@ static ERTS_INLINE void async_add(ErtsAsync *a, ErtsAsyncQ* q)
 #endif
 
     erts_thr_q_enqueue(&q->thr_q, a);
+    if (DTRACE_ENABLED(aio_pool_add)) {
+        DTRACE_CHARBUF(port_str, 16);
+
+        erts_snprintf(port_str, sizeof(port_str), "%T", a->port);
+        DTRACE2(aio_pool_add, port_str, len);
+    }
+    gcc_optimizer_hack++;
 }
 
 static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
@@ -269,6 +288,8 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
     int saved_fin_deq = 0;
     ErtsThrQFinDeQ_t fin_deq;
 #endif
+    /* DTRACE TODO: Get the queue length from erts_thr_q_dequeue() somehow? */
+    int len = -1;
 
     while (1) {
 	ErtsAsync *a = (ErtsAsync *) erts_thr_q_dequeue(q);
@@ -280,7 +301,12 @@ static ERTS_INLINE ErtsAsync *async_get(ErtsThrQ_t *q,
 	    if (saved_fin_deq)
 		erts_thr_q_append_finalize_dequeue_data(&a->q.fin_deq, &fin_deq);
 #endif
+            if (DTRACE_ENABLED(aio_pool_get)) {
+                DTRACE_CHARBUF(port_str, 16);
 
+                erts_snprintf(port_str, sizeof(port_str), "%T", a->port);
+                DTRACE2(aio_pool_get, port_str, len);
+            }
 	    return a;
 	}
 
diff --git a/erts/emulator/beam/erl_bif_ddll.c b/erts/emulator/beam/erl_bif_ddll.c
index 37d540b41b..3326fd84df 100644
--- a/erts/emulator/beam/erl_bif_ddll.c
+++ b/erts/emulator/beam/erl_bif_ddll.c
@@ -45,6 +45,7 @@
 #include "big.h"
 #include "dist.h"
 #include "erl_version.h"
+#include "dtrace-wrapper.h"
 
 #ifdef ERTS_SMP
 #define DDLL_SMP 1
@@ -1647,6 +1648,7 @@ static int do_unload_driver_entry(DE_Handle *dh, Eterm *save_name)
 	       diver_list lock here!*/
 	    if (q->finish) {
 		int fpe_was_unmasked = erts_block_fpe();
+		DTRACE1(driver_finish, q->name);
 		(*(q->finish))();
 		erts_unblock_fpe(fpe_was_unmasked);
 	    }
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index ebd475f73a..90bbb34927 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -115,6 +115,9 @@ static char erts_system_version[] = ("Erlang " ERLANG_OTP_RELEASE
 #ifdef VALGRIND
 				     " [valgrind-compiled]"
 #endif
+#ifdef HAVE_DTRACE
+				     " [dtrace]"
+#endif
 				     "\n");
 
 #define ASIZE(a) (sizeof(a)/sizeof(a[0]))
diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index cd423eb200..8caa64b97d 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -40,6 +40,7 @@
 #include "external.h"
 #include "packet_parser.h"
 #include "erl_bits.h"
+#include "dtrace-wrapper.h"
 
 static int open_port(Process* p, Eterm name, Eterm settings, int *err_nump);
 static byte* convert_environment(Process* p, Eterm env);
@@ -343,6 +344,14 @@ port_call(Process* c_p, Eterm arg1, Eterm arg2, Eterm arg3)
 		 __FILE__, __LINE__, endp - (bytes + size));
     }
     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
+    if (DTRACE_ENABLED(driver_call)) {
+        DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_pid_str(p->connected, process_str);
+        dtrace_port_str(p, port_str);
+        DTRACE5(driver_call, process_str, port_str, p->name, op, real_size);
+    }
     prc  = (char *) port_resp;
     fpe_was_unmasked = erts_block_fpe();
     ret = drv->call((ErlDrvData)p->drv_data, 
@@ -539,6 +548,16 @@ BIF_RETTYPE port_connect_2(BIF_ALIST_2)
 
     prt->connected = pid; /* internal pid */
     erts_smp_port_unlock(prt);
+    if (DTRACE_ENABLED(port_connect)) {
+        DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(newprocess_str, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_pid_str(prt->connected, process_str);
+        erts_snprintf(port_str, sizeof(port_str), "%T", prt->id);
+        dtrace_proc_str(rp, newprocess_str);
+        DTRACE4(port_connect, process_str, port_str, prt->name, newprocess_str);
+    }
     BIF_RET(am_true);
 }
 
@@ -904,6 +923,14 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_nump)
     erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
 
     port_num = erts_open_driver(driver, p->id, name_buf, &opts, err_nump);
+    if (port_num >= 0 && DTRACE_ENABLED(port_open)) {
+        DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, process_str);
+        erts_snprintf(port_str, sizeof(port_str), "%T", erts_port[port_num].id);
+        DTRACE3(port_open, process_str, name_buf, port_str);
+    }
 
     erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
 
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index bde87b8346..858ae32ad5 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -35,6 +35,7 @@
 #include "hipe_stack.h"
 #include "hipe_mode_switch.h"
 #endif
+#include "dtrace-wrapper.h"
 
 #define ERTS_INACT_WR_PB_LEAVE_MUCH_LIMIT 1
 #define ERTS_INACT_WR_PB_LEAVE_MUCH_PERCENTAGE 20
@@ -349,6 +350,7 @@ erts_garbage_collect(Process* p, int need, Eterm* objv, int nobj)
     Uint reclaimed_now = 0;
     int done = 0;
     Uint ms1, s1, us1;
+    DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
 
     if (IS_TRACED_FL(p, F_TRACE_GC)) {
         trace_gc(p, am_gc_start);
@@ -370,14 +372,26 @@ erts_garbage_collect(Process* p, int need, Eterm* objv, int nobj)
         FLAGS(p) |= F_NEED_FULLSWEEP;
     }
 
+    *pidbuf = '\0';
+    if (DTRACE_ENABLED(gc_major_start)
+        || DTRACE_ENABLED(gc_major_end)
+        || DTRACE_ENABLED(gc_minor_start)
+        || DTRACE_ENABLED(gc_minor_end)) {
+        dtrace_proc_str(p, pidbuf);
+    }
+
     /*
      * Test which type of GC to do.
      */
     while (!done) {
 	if ((FLAGS(p) & F_NEED_FULLSWEEP) != 0) {
+	    DTRACE2(gc_major_start, pidbuf, need);
 	    done = major_collection(p, need, objv, nobj, &reclaimed_now);
+	    DTRACE2(gc_major_end, pidbuf, reclaimed_now);
 	} else {
+	    DTRACE2(gc_minor_start, pidbuf, need);
 	    done = minor_collection(p, need, objv, nobj, &reclaimed_now);
+	    DTRACE2(gc_minor_end, pidbuf, reclaimed_now);
 	}
     }
 
@@ -1118,6 +1132,13 @@ do_minor(Process *p, Uint new_sz, Eterm* objv, int nobj)
     sys_memcpy(n_heap + new_sz - n, p->stop, n * sizeof(Eterm));
     p->stop = n_heap + new_sz - n;
 
+    if (HEAP_SIZE(p) != new_sz && DTRACE_ENABLED(process_heap_grow)) {
+        DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, pidbuf);
+        DTRACE3(process_heap_grow, pidbuf, HEAP_SIZE(p), new_sz);
+    }
+
     ERTS_HEAP_FREE(ERTS_ALC_T_HEAP,
 		   (void*)HEAP_START(p),
 		   HEAP_SIZE(p) * sizeof(Eterm));
@@ -1339,6 +1360,13 @@ major_collection(Process* p, int need, Eterm* objv, int nobj, Uint *recl)
     sys_memcpy(n_heap + new_sz - n, p->stop, n * sizeof(Eterm));
     p->stop = n_heap + new_sz - n;
 
+    if (HEAP_SIZE(p) != new_sz && DTRACE_ENABLED(process_heap_grow)) {
+        DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, pidbuf);
+        DTRACE3(process_heap_grow, pidbuf, HEAP_SIZE(p), new_sz);
+    }
+
     ERTS_HEAP_FREE(ERTS_ALC_T_HEAP,
 		   (void *) HEAP_START(p),
 		   (HEAP_END(p) - HEAP_START(p)) * sizeof(Eterm));
@@ -2009,6 +2037,14 @@ grow_new_heap(Process *p, Uint new_sz, Eterm* objv, int nobj)
         HEAP_TOP(p) = new_heap + heap_size;
         HEAP_START(p) = new_heap;
     }
+
+    if (DTRACE_ENABLED(process_heap_grow)) {
+	DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, pidbuf);
+	DTRACE3(process_heap_grow, pidbuf, HEAP_SIZE(p), new_sz);
+    }
+
     HEAP_SIZE(p) = new_sz;
 }
 
@@ -2018,8 +2054,8 @@ shrink_new_heap(Process *p, Uint new_sz, Eterm *objv, int nobj)
     Eterm* new_heap;
     Uint heap_size = HEAP_TOP(p) - HEAP_START(p);
     Sint offs;
-
     Uint stack_size = p->hend - p->stop;
+    char pidbuf[DTRACE_TERM_BUF_SIZE];
 
     ASSERT(new_sz < p->heap_sz);
     sys_memmove(p->heap + new_sz - stack_size, p->stop, stack_size *
@@ -2047,6 +2083,14 @@ shrink_new_heap(Process *p, Uint new_sz, Eterm *objv, int nobj)
         HEAP_TOP(p) = new_heap + heap_size;
         HEAP_START(p) = new_heap;
     }
+
+    if (DTRACE_ENABLED(process_heap_shrink)) {
+	DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, pidbuf);
+	DTRACE3(process_heap_shrink, pidbuf, HEAP_SIZE(p), new_sz);
+    }
+
     HEAP_SIZE(p) = new_sz;
 }
 
diff --git a/erts/emulator/beam/erl_lock_check.c b/erts/emulator/beam/erl_lock_check.c
index 09e85893c3..561570c30e 100644
--- a/erts/emulator/beam/erl_lock_check.c
+++ b/erts/emulator/beam/erl_lock_check.c
@@ -183,6 +183,9 @@ static erts_lc_lock_order_t erts_lock_order[] = {
     {   "save_ops_lock",                        NULL                    },
 #endif
 #endif
+#ifdef	HAVE_DTRACE
+    {   "efile_drv dtrace mutex",               NULL                    },
+#endif
     {	"mtrace_buf",				NULL			},
     {	"erts_alloc_hard_debug",		NULL			}
 };
diff --git a/erts/emulator/beam/erl_message.c b/erts/emulator/beam/erl_message.c
index ab1ab7b1ea..8489353c9e 100644
--- a/erts/emulator/beam/erl_message.c
+++ b/erts/emulator/beam/erl_message.c
@@ -31,6 +31,7 @@
 #include "erl_process.h"
 #include "erl_nmgc.h"
 #include "erl_binary.h"
+#include "dtrace-wrapper.h"
 
 ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(message,
 				 ErlMessage,
@@ -335,6 +336,7 @@ erts_queue_dist_message(Process *rcvr,
 			Eterm token)
 {
     ErlMessage* mp;
+    Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
 #ifdef ERTS_SMP
     ErtsProcLocks need_locks;
 #endif
@@ -376,6 +378,19 @@ erts_queue_dist_message(Process *rcvr,
 	message_free(mp);
 	msg = erts_msg_distext2heap(rcvr, rcvr_locks, &mbuf, &token, dist_ext);
 	if (is_value(msg))
+            if (DTRACE_ENABLED(message_queued)) {
+                DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
+
+                dtrace_proc_str(rcvr, receiver_name);
+                if (token != NIL) {
+                    tok_label = signed_val(SEQ_TRACE_T_LABEL(token));
+                    tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token));
+                    tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token));
+                }
+                DTRACE6(message_queued,
+                        receiver_name, size_object(msg), rcvr->msg.len,
+                        tok_label, tok_lastcnt, tok_serial);
+            }
 	    erts_queue_message(rcvr, rcvr_locks, mbuf, msg, token);
     }
     else {
@@ -385,6 +400,22 @@ erts_queue_dist_message(Process *rcvr,
 	ERL_MESSAGE_TOKEN(mp) = token;
 	mp->next = NULL;
 
+        if (DTRACE_ENABLED(message_queued)) {
+            DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
+
+            dtrace_proc_str(rcvr, receiver_name);
+            if (token != NIL) {
+                tok_label = signed_val(SEQ_TRACE_T_LABEL(token));
+                tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token));
+                tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token));
+            }
+            /*
+             * TODO: We don't know the real size of the external message here.
+             *       -1 will appear to a D script as 4294967295.
+             */
+            DTRACE6(message_queued, receiver_name, -1, rcvr->msg.len + 1,
+                    tok_label, tok_lastcnt, tok_serial);
+        }
 	mp->data.dist_ext = dist_ext;
 	LINK_MESSAGE(rcvr, mp);
 
@@ -462,12 +493,27 @@ erts_queue_message(Process* receiver,
     LINK_MESSAGE(receiver, mp);
 #endif
 
+    if (DTRACE_ENABLED(message_queued)) {
+        DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE);
+        Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
+
+        dtrace_proc_str(receiver, receiver_name);
+        if (seq_trace_token != NIL && is_tuple(seq_trace_token)) {
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(seq_trace_token));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(seq_trace_token));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(seq_trace_token));
+        }
+        DTRACE6(message_queued,
+                receiver_name, size_object(message), receiver->msg.len,
+                tok_label, tok_lastcnt, tok_serial);
+    }
+
     notify_new_message(receiver);
 
     if (IS_TRACED_FL(receiver, F_TRACE_RECEIVE)) {
 	trace_receive(receiver, message);
     }
-    
+
 #ifndef ERTS_SMP
     ERTS_HOLE_CHECK(receiver);
 #endif
@@ -774,11 +820,19 @@ erts_send_message(Process* sender,
     Uint msize;
     ErlHeapFragment* bp = NULL;
     Eterm token = NIL;
+    DTRACE_CHARBUF(sender_name, 64);
+    DTRACE_CHARBUF(receiver_name, 64);
+    Sint tok_label = 0, tok_lastcnt = 0, tok_serial = 0;
 
     BM_STOP_TIMER(system);
     BM_MESSAGE(message,sender,receiver);
     BM_START_TIMER(send);
 
+    *sender_name = *receiver_name = '\0';
+    if (DTRACE_ENABLED(message_send)) {
+        erts_snprintf(sender_name, sizeof(sender_name), "%T", sender->id);
+        erts_snprintf(receiver_name, sizeof(receiver_name), "%T", receiver->id);
+    }
     if (SEQ_TRACE_TOKEN(sender) != NIL && !(flags & ERTS_SND_FLG_NO_SEQ_TRACE)) {
         Eterm* hp;
 
@@ -802,6 +856,16 @@ erts_send_message(Process* sender,
         BM_MESSAGE_COPIED(msize);
         BM_SWAP_TIMER(copy,send);
 
+        if (DTRACE_ENABLED(message_send)) {
+            Eterm token2 = NIL;
+
+            token2 = SEQ_TRACE_TOKEN(sender);
+            tok_label = signed_val(SEQ_TRACE_T_LABEL(token2));
+            tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token2));
+            tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token2));
+            DTRACE6(message_send, sender_name, receiver_name,
+                    msize, tok_label, tok_lastcnt, tok_serial);
+        }
         erts_queue_message(receiver,
 			   receiver_locks,
 			   bp,
@@ -835,6 +899,8 @@ erts_send_message(Process* sender,
 #endif
         LAZY_COPY(sender,message);
         BM_SWAP_TIMER(copy,send);
+        DTRACE6(message_send, sender_name, receiver_name,
+                size_object(message)msize, tok_label, tok_lastcnt, tok_serial);
         ERL_MESSAGE_TERM(mp) = message;
         ERL_MESSAGE_TOKEN(mp) = NIL;
         mp->next = NULL;
@@ -874,6 +940,8 @@ erts_send_message(Process* sender,
 	{
 	    ErlMessage* mp = message_alloc();
 
+            DTRACE6(message_send, sender_name, receiver_name,
+                    size_object(message), tok_label, tok_lastcnt, tok_serial);
 	    mp->data.attached = NULL;
 	    ERL_MESSAGE_TERM(mp) = message;
 	    ERL_MESSAGE_TOKEN(mp) = NIL;
@@ -908,6 +976,8 @@ erts_send_message(Process* sender,
 	message = copy_struct(message, msize, &hp, ohp);
 	BM_MESSAGE_COPIED(msz);
 	BM_SWAP_TIMER(copy,send);
+        DTRACE6(message_send, sender_name, receiver_name,
+                msize, tok_label, tok_lastcnt, tok_serial);
 	erts_queue_message(receiver, receiver_locks, bp, message, token);
         BM_SWAP_TIMER(send,system);
 #else
@@ -928,6 +998,8 @@ erts_send_message(Process* sender,
 	message = copy_struct(message, msize, &hp, &receiver->off_heap);
 	BM_MESSAGE_COPIED(msize);
         BM_SWAP_TIMER(copy,send);
+        DTRACE6(message_send, sender_name, receiver_name,
+                (uint32_t)msize, tok_label, tok_lastcnt, tok_serial);
 	ERL_MESSAGE_TERM(mp) = message;
 	ERL_MESSAGE_TOKEN(mp) = NIL;
 	mp->next = NULL;
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 58a09986d2..dc4049327d 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -66,6 +66,7 @@ static void add_readonly_check(ErlNifEnv*, unsigned char* ptr, unsigned sz);
 static int is_offheap(const ErlOffHeap* off_heap);
 #endif
 
+void dtrace_nifenv_str(ErlNifEnv *, char *);
 
 #define MIN_HEAP_FRAG_SZ 200
 static Eterm* alloc_heap_heavy(ErlNifEnv* env, unsigned need, Eterm* hp);
@@ -1779,6 +1780,11 @@ void erl_nif_init()
     resource_type_list.name = THE_NON_VALUE;
 }
 
+void dtrace_nifenv_str(ErlNifEnv *env, char *process_buf)
+{
+    dtrace_pid_str(env->proc->id, process_buf);
+}
+
 #ifdef READONLY_CHECK
 /* Use checksums to assert that NIFs do not write into inspected binaries
 */
diff --git a/erts/emulator/beam/erl_node_tables.c b/erts/emulator/beam/erl_node_tables.c
index 908ba755ed..1481f66b55 100644
--- a/erts/emulator/beam/erl_node_tables.c
+++ b/erts/emulator/beam/erl_node_tables.c
@@ -27,6 +27,7 @@
 #include "big.h"
 #include "error.h"
 #include "erl_thr_progress.h"
+#include "dtrace-wrapper.h"
 
 Hash erts_dist_table;
 Hash erts_node_table;
@@ -42,6 +43,8 @@ Sint erts_no_of_not_connected_dist_entries;
 
 DistEntry *erts_this_dist_entry;
 ErlNode *erts_this_node;
+char erts_this_node_sysname_BUFFER[256],
+    *erts_this_node_sysname = "uninitialized yet";
 
 static Uint node_entries;
 static Uint dist_entries;
@@ -702,6 +705,9 @@ erts_set_this_node(Eterm sysname, Uint creation)
     (void) hash_erase(&erts_node_table, (void *) erts_this_node);
     erts_this_node->sysname = sysname;
     erts_this_node->creation = creation;
+    erts_this_node_sysname = erts_this_node_sysname_BUFFER;
+    erts_snprintf(erts_this_node_sysname, sizeof(erts_this_node_sysname),
+                  "%T", sysname);
     (void) hash_put(&erts_node_table, (void *) erts_this_node);
 
     erts_smp_rwmtx_rwunlock(&erts_dist_table_rwmtx);
@@ -789,6 +795,9 @@ void erts_init_node_tables(void)
     erts_this_node->sysname			= am_Noname;
     erts_this_node->creation			= 0;
     erts_this_node->dist_entry			= erts_this_dist_entry;
+    erts_this_node_sysname = erts_this_node_sysname_BUFFER;
+    erts_snprintf(erts_this_node_sysname, sizeof(erts_this_node_sysname),
+                  "%T", erts_this_node->sysname);
 
     (void) hash_put(&erts_node_table, (void *) erts_this_node);
 
diff --git a/erts/emulator/beam/erl_node_tables.h b/erts/emulator/beam/erl_node_tables.h
index 8abb748a78..5cfd0ac641 100644
--- a/erts/emulator/beam/erl_node_tables.h
+++ b/erts/emulator/beam/erl_node_tables.h
@@ -169,7 +169,7 @@ extern Sint erts_no_of_not_connected_dist_entries;
 
 extern DistEntry *erts_this_dist_entry;
 extern ErlNode *erts_this_node;
-extern char erts_this_node_sysname[256]; /* must match erl_node_tables.c */
+extern char *erts_this_node_sysname; /* must match erl_node_tables.c */
 
 DistEntry *erts_channel_no_to_dist_entry(Uint);
 DistEntry *erts_sysname_to_connected_dist_entry(Eterm);
diff --git a/erts/emulator/beam/erl_port_task.c b/erts/emulator/beam/erl_port_task.c
index a2b08fcf56..25bba5cf17 100644
--- a/erts/emulator/beam/erl_port_task.c
+++ b/erts/emulator/beam/erl_port_task.c
@@ -32,6 +32,7 @@
 #include "global.h"
 #include "erl_port_task.h"
 #include "dist.h"
+#include "dtrace-wrapper.h"
 
 #if defined(DEBUG) && 0
 #define HARD_DEBUG
@@ -61,6 +62,16 @@ do {					\
     (P)->sched.next = NULL;		\
 } while (0)
 
+#define DTRACE_DRIVER(PROBE_NAME, PP)                              \
+    if (DTRACE_ENABLED(driver_ready_input)) {                      \
+        DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);         \
+        DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);            \
+                                                                   \
+        dtrace_pid_str(PP->connected, process_str);                \
+        dtrace_port_str(PP, port_str);                             \
+        DTRACE3(PROBE_NAME, process_str, port_str, PP->name);      \
+    }
+
 erts_smp_atomic_t erts_port_task_outstanding_io_tasks;
 
 struct ErtsPortTaskQueue_ {
@@ -823,12 +834,15 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	    goto tasks_done;
 	case ERTS_PORT_TASK_TIMEOUT:
 	    reds += ERTS_PORT_REDS_TIMEOUT;
-	    if (!(pp->status & ERTS_PORT_SFLGS_DEAD))
+	    if (!(pp->status & ERTS_PORT_SFLGS_DEAD)) {
+                DTRACE_DRIVER(driver_timeout, pp);
 		(*pp->drv_ptr->timeout)((ErlDrvData) pp->drv_data);
+            }
 	    break;
 	case ERTS_PORT_TASK_INPUT:
 	    reds += ERTS_PORT_REDS_INPUT;
 	    ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
+            DTRACE_DRIVER(driver_ready_input, pp);
 	    /* NOTE some windows drivers use ->ready_input for input and output */
 	    (*pp->drv_ptr->ready_input)((ErlDrvData) pp->drv_data, ptp->event);
 	    io_tasks_executed++;
@@ -836,12 +850,14 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
 	case ERTS_PORT_TASK_OUTPUT:
 	    reds += ERTS_PORT_REDS_OUTPUT;
 	    ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
+            DTRACE_DRIVER(driver_ready_output, pp);
 	    (*pp->drv_ptr->ready_output)((ErlDrvData) pp->drv_data, ptp->event);
 	    io_tasks_executed++;
 	    break;
 	case ERTS_PORT_TASK_EVENT:
 	    reds += ERTS_PORT_REDS_EVENT;
 	    ASSERT((pp->status & ERTS_PORT_SFLGS_DEAD) == 0);
+            DTRACE_DRIVER(driver_event, pp);
 	    (*pp->drv_ptr->event)((ErlDrvData) pp->drv_data, ptp->event, ptp->event_data);
 	    io_tasks_executed++;
 	    break;
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index 45f6dc800c..1173624f51 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -42,6 +42,7 @@
 #include "erl_thr_progress.h"
 #include "erl_thr_queue.h"
 #include "erl_async.h"
+#include "dtrace-wrapper.h"
 
 #define ERTS_RUNQ_CHECK_BALANCE_REDS_PER_SCHED (2000*CONTEXT_REDS)
 #define ERTS_RUNQ_CALL_CHECK_BALANCE_REDS \
@@ -6214,6 +6215,13 @@ Process *schedule(Process *p, int calls)
     int actual_reds;
     int reds;
 
+    if (p != NULL && DTRACE_ENABLED(process_unscheduled)) {
+        DTRACE_CHARBUF(process_buf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_proc_str(p, process_buf);
+        DTRACE1(process_unscheduled, process_buf);
+    }
+
     if (ERTS_USE_MODIFIED_TIMING()) {
 	context_reds = ERTS_MODIFIED_TIMING_CONTEXT_REDS;
 	input_reductions = ERTS_MODIFIED_TIMING_INPUT_REDS;
@@ -7384,6 +7392,14 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
 
     VERBOSE(DEBUG_PROCESSES, ("Created a new process: %T\n",p->id));
 
+    if (DTRACE_ENABLED(process_spawn)) {
+        DTRACE_CHARBUF(process_name, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(mfa, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_fun_decode(p, mod, func, arity, process_name, mfa);
+        DTRACE2(process_spawn, process_name, mfa);
+    }
+
  error:
 
     erts_smp_proc_unlock(parent, ERTS_PROC_LOCKS_ALL_MINOR);
@@ -7952,6 +7968,17 @@ send_exit_signal(Process *c_p,		/* current process if and only
 
     ASSERT(reason != THE_NON_VALUE);
 
+    if(DTRACE_ENABLED(process_exit_signal) && is_pid(from)) {
+        DTRACE_CHARBUF(sender_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(receiver_str, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(reason_buf, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_pid_str(from, sender_str);
+        dtrace_proc_str(rp, receiver_str);
+        erts_snprintf(reason_buf, sizeof(reason_buf) - 1, "%T", reason);
+        DTRACE3(process_exit_signal, sender_str, receiver_str, reason_buf);
+    }
+
     if (ERTS_PROC_IS_TRAPPING_EXITS(rp)
 	&& (reason != am_kill || (flags & ERTS_XSIG_FLG_IGN_KILL))) {
 	if (is_not_nil(token) && token_update)
@@ -8378,7 +8405,16 @@ erts_do_exit_process(Process* p, Eterm reason)
 
     p->arity = 0;		/* No live registers */
     p->fvalue = reason;
-    
+
+    if (DTRACE_ENABLED(process_exit)) {
+        DTRACE_CHARBUF(process_buf, DTRACE_TERM_BUF_SIZE);
+        DTRACE_CHARBUF(reason_buf, 256);
+
+        dtrace_proc_str(p, process_buf);
+        erts_snprintf(reason_buf, sizeof(reason_buf) - 1, "%T", reason);
+        DTRACE2(process_exit, process_buf, reason_buf);
+    }
+
 #ifdef ERTS_SMP
     ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
     /* By locking all locks (main lock is already locked) when going
diff --git a/erts/emulator/beam/erlang_dtrace.d b/erts/emulator/beam/erlang_dtrace.d
new file mode 100644
index 0000000000..d8508426f4
--- /dev/null
+++ b/erts/emulator/beam/erlang_dtrace.d
@@ -0,0 +1,716 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Dustin Sallings, Michal Ptaszek, Scott Lystig Fritchie 2011.
+ * All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+/*
+ * A note on probe naming: if "__" appears in a provider probe
+ * definition, then two things happen during compilation:
+ *
+ *    1. The "__" will turn into a hypen, "-", for the probe name.
+ *    2. The "__" will turn into a single underscore, "_", for the
+ *       macro names and function definitions that the compiler and
+ *       C developers will see.
+ *
+ * We'll try to use the following naming convention.  We're a bit
+ * limited because, as a USDT probe, we can only specify the 4th part
+ * of the probe name, e.g. erlang*:::mumble.  The 2nd part of the
+ * probe name is always going to be "beam" or "beam.smp", and the 3rd
+ * part of the probe name will always be the name of the function
+ * that's calling the probe.
+ *
+ * So, all probes will be have names defined in this file using the
+ * convention category__name or category__sub_category__name.  This
+ * will translate to probe names of category-name or
+ * category-sub_category-name.
+ *
+ * Each of "category", "sub_category", and "name" may have underscores
+ * but may not have hyphens.
+ */
+
+provider erlang {
+    /**
+     * Fired when a message is sent from one local process to another.
+     *
+     * NOTE: The 'size' parameter is in machine-dependent words and
+     *       that the actual size of any binary terms in the message
+     *       are not included.
+     *
+     * @param sender the PID (string form) of the sender
+     * @param receiver the PID (string form) of the receiver
+     * @param size the size of the message being delivered (words)
+     * @param token_label for the sender's sequential trace token
+     * @param token_previous count for the sender's sequential trace token
+     * @param token_current count for the sender's sequential trace token
+     */
+    probe message__send(char *sender, char *receiver, uint32_t size,
+                        int token_label, int token_previous, int token_current);
+
+    /**
+     * Fired when a message is sent from a local process to a remote process.
+     *
+     * NOTE: The 'size' parameter is in machine-dependent words and
+     *       that the actual size of any binary terms in the message
+     *       are not included.
+     *
+     * @param sender the PID (string form) of the sender
+     * @param node_name the Erlang node name (string form) of the receiver
+     * @param receiver the PID/name (string form) of the receiver
+     * @param size the size of the message being delivered (words)
+     * @param token_label for the sender's sequential trace token
+     * @param token_previous count for the sender's sequential trace token
+     * @param token_current count for the sender's sequential trace token
+     */
+    probe message__send__remote(char *sender, char *node_name, char *receiver,
+                                uint32_t size,
+                        int token_label, int token_previous, int token_current);
+
+    /**
+     * Fired when a message is queued to a local process.  This probe
+     * will not fire if the sender's pid == receiver's pid.
+     *
+     * NOTE: The 'size' parameter is in machine-dependent words and
+     *       that the actual size of any binary terms in the message
+     *       are not included.
+     *
+     * NOTE: In cases of messages in external format (i.e. from another
+     *       Erlang node), we probably don't know the message size
+     *       without performing substantial extra computation.  To
+     *       avoid the extra CPU overhead, the message size may be
+     *       reported as -1, which can appear to a D script as 4294967295.
+     *
+     * @param receiver the PID (string form) of the receiver
+     * @param size the size of the message being delivered (words)
+     * @param queue_len length of the queue of the receiving process
+     * @param token_label for the sender's sequential trace token
+     * @param token_previous count for the sender's sequential trace token
+     * @param token_current count for the sender's sequential trace token
+     */
+    probe message__queued(char *receiver, uint32_t size, uint32_t queue_len,
+                        int token_label, int token_previous, int token_current);
+
+    /**
+     * Fired when a message is 'receive'd by a local process and removed
+     * from its mailbox.
+     *
+     * NOTE: The 'size' parameter is in machine-dependent words and
+     *       that the actual size of any binary terms in the message
+     *       are not included.
+     *
+     * NOTE: In cases of messages in external format (i.e. from another
+     *       Erlang node), we probably don't know the message size
+     *       without performing substantial extra computation.  To
+     *       avoid the extra CPU overhead, the message size may be
+     *       reported as -1, which can appear to a D script as 4294967295.
+     *
+     * @param receiver the PID (string form) of the receiver
+     * @param size the size of the message being delivered (words)
+     * @param queue_len length of the queue of the receiving process
+     * @param token_label for the sender's sequential trace token
+     * @param token_previous count for the sender's sequential trace token
+     * @param token_current count for the sender's sequential trace token
+     */
+    probe message__receive(char *receiver, uint32_t size, uint32_t queue_len,
+                        int token_label, int token_previous, int token_current);
+
+    /**
+     * Fired when an Eterm structure is being copied.
+     *
+     * NOTE: Due to the placement of this probe, the process ID of
+     *       owner of the Eterm is not available.
+     *
+     * @param size the size of the structure
+     */
+    probe copy__struct(uint32_t size);
+
+    /**
+     * Fired when an Eterm is being copied onto a process.
+     *
+     * @param proc the PID (string form) of the recipient process
+     * @param size the size of the structure
+     */
+    probe copy__object(char *proc, uint32_t size);
+
+    /* PID, Module, Function, Arity */
+
+    /**
+     * Fired whenever a user function is being called.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     * @param depth the stack depth
+     */
+    probe function__entry(char *p, char *mfa, int depth);
+
+    /**
+     * Fired whenever a user function returns.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     * @param depth the stack depth
+     */
+    probe function__return(char *p, char *mfa, int depth);
+
+    /**
+     * Fired whenever a Built In Function is called.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     */
+    probe bif__entry(char *p, char *mfa);
+
+    /**
+     * Fired whenever a Built In Function returns.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     */
+    probe bif__return(char *p, char *mfa);
+
+    /**
+     * Fired whenever a Native Function is called.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     */
+    probe nif__entry(char *p, char *mfa);
+
+    /**
+     * Fired whenever a Native Function returns.
+     *
+     * @param p the PID (string form) of the process
+     * @param mfa the m:f/a of the function
+     */
+    probe nif__return(char *p, char *mfa);
+
+    /**
+     * Fired when a major GC is starting.
+     *
+     * @param p the PID (string form) of the exiting process
+     * @param need the number of words needed on the heap
+     */
+    probe gc_major__start(char *p, int need);
+
+    /**
+     * Fired when a minor GC is starting.
+     *
+     * @param p the PID (string form) of the exiting process
+     * @param need the number of words needed on the heap
+     */
+    probe gc_minor__start(char *p, int need);
+
+    /**
+     * Fired when a major GC is starting.
+     *
+     * @param p the PID (string form) of the exiting process
+     * @param reclaimed the amount of space reclaimed
+     */
+    probe gc_major__end(char *p, int reclaimed);
+
+    /**
+     * Fired when a minor GC is starting.
+     *
+     * @param p the PID (string form) of the exiting process
+     * @param reclaimed the amount of space reclaimed
+     */
+    probe gc_minor__end(char *p, int reclaimed);
+
+    /**
+     * Fired when a process is spawned.
+     *
+     * @param p the PID (string form) of the new process.
+     * @param mfa the m:f/a of the function
+     */
+    probe process__spawn(char *p, char *mfa);
+
+    /**
+     * Fired when a process is exiting.
+     *
+     * @param p the PID (string form) of the exiting process
+     * @param reason the reason for the exit (may be truncated)
+     */
+    probe process__exit(char *p, char *reason);
+
+    /**
+     * Fired when exit signal is delivered to a local process.
+     *
+     * @param sender the PID (string form) of the exiting process
+     * @param receiver the PID (string form) of the process receiving EXIT signal
+     * @param reason the reason for the exit (may be truncated)
+     */
+    probe process__exit_signal(char *sender, char *receiver, char *reason);
+
+    /**
+     * Fired when exit signal is delivered to a remote process.
+     *
+     * @param sender the PID (string form) of the exiting process
+     * @param node_name the Erlang node name (string form) of the receiver
+     * @param receiver the PID (string form) of the process receiving EXIT signal
+     * @param reason the reason for the exit (may be truncated)
+     * @param token_label for the sender's sequential trace token
+     * @param token_previous count for the sender's sequential trace token
+     * @param token_current count for the sender's sequential trace token
+     */
+    probe process__exit_signal__remote(char *sender, char *node_name,
+                                       char *receiver, char *reason,
+                        int token_label, int token_previous, int token_current);
+
+    /**
+     * Fired when a process is scheduled.
+     *
+     * @param p the PID (string form) of the newly scheduled process
+     * @param mfa the m:f/a of the function it should run next
+     */
+    probe process__scheduled(char *p, char *mfa);
+
+    /**
+     * Fired when a process is unscheduled.
+     *
+     * @param p the PID (string form) of the process that has been
+     * unscheduled.
+     */
+    probe process__unscheduled(char *p);
+
+    /**
+     * Fired when a process goes into hibernation.
+     *
+     * @param p the PID (string form) of the process entering hibernation
+     * @param mfa the m:f/a of the location to resume
+     */
+    probe process__hibernate(char *p, char *mfa);
+
+    /**
+     * Fired when a process is unblocked after a port has been unblocked.
+     *
+     * @param p the PID (string form) of the process that has been
+     * unscheduled.
+     * @param port the port that is no longer busy (i.e., is now unblocked)
+     */
+    probe process__port_unblocked(char *p, char *port);
+
+    /**
+     * Fired when process' heap is growing.
+     *
+     * @param p the PID (string form)
+     * @param old_size the size of the old heap
+     * @param new_size the size of the new heap
+     */
+    probe process__heap_grow(char *p, int old_size, int new_size);
+
+    /**
+     * Fired when process' heap is shrinking.
+     *
+     * @param p the PID (string form)
+     * @param old_size the size of the old heap
+     * @param new_size the size of the new heap
+     */
+    probe process__heap_shrink(char *p, int old_size, int new_size);
+
+    /* network distribution */
+
+    /**
+     * Fired when network distribution event monitor events are triggered.
+     *
+     * @param node the name of the reporting node
+     * @param what the type of event, e.g., nodeup, nodedown
+     * @param monitored_node the name of the monitored node
+     * @param type the type of node, e.g., visible, hidden
+     * @param reason the reason term, e.g., normal, connection_closed, term()
+     */
+    probe dist__monitor(char *node, char *what, char *monitored_node,
+                        char *type, char *reason);
+
+    /**
+     * Fired when network distribution port is busy (i.e. blocked),
+     * usually due to the remote node not consuming distribution
+     * data quickly enough.
+     *
+     * @param node the name of the reporting node
+     * @param port the port ID of the busy port
+     * @param remote_node the name of the remote node.
+     * @param pid the PID (string form) of the local process that has
+     *        become unschedulable until the port becomes unblocked.
+     */
+    probe dist__port_busy(char *node, char *port, char *remote_node,
+                          char *pid);
+
+    /**
+     * Fired when network distribution's driver's "output" callback is called
+     *
+     * @param node the name of the reporting node
+     * @param port the port ID of the busy port
+     * @param remote_node the name of the remote node.
+     * @param bytes the number of bytes written
+     */
+    probe dist__output(char *node, char *port, char *remote_node, int bytes);
+
+    /**
+     * Fired when network distribution's driver's "outputv" callback is called
+     *
+     * @param node the name of the reporting node
+     * @param port the port ID of the busy port
+     * @param remote_node the name of the remote node.
+     * @param bytes the number of bytes written
+     */
+    probe dist__outputv(char *node, char *port, char *remote_node, int bytes);
+
+    /**
+     * Fired when network distribution port is no longer busy (i.e. blocked).
+     *
+     * NOTE: This probe may fire multiple times after the same single
+     *       dist-port_busy probe firing.
+     *
+     * @param node the name of the reporting node
+     * @param port the port ID of the busy port
+     * @param remote_node the name of the remote node.
+     */
+    probe dist__port_not_busy(char *node, char *port, char *remote_node);
+
+    /* ports */
+
+    /**
+     * Fired when new port is opened.
+     *
+     * @param process the PID (string form)
+     * @param port_name the string used when the port was opened
+     * @param port the Port (string form) of the new port
+     */
+    probe port__open(char *process, char *port_name, char *port);
+
+    /**
+     * Fired when port_command is issued.
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param command_type type of the issued command, one of: "close", "command" or "connect"
+     */
+    probe port__command(char *process, char *port, char *port_name, char *command_type);
+
+    /**
+     * Fired when port_control is issued.
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param command_no command number that has been issued to the port
+     */
+    probe port__control(char *process, char *port, char *port_name, int command_no);
+
+    /**
+     * Fired when port is closed via port_close/1 (reason = 'normal')
+     * or is sent an exit signal.
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param reason Erlang term representing the exit signal, e.g. 'normal'
+     */
+    probe port__exit(char *process, char *port, char *port_name,
+                     char *new_process);
+
+    /**
+     * Fired when port_connect is issued.
+     *
+     * @param process the PID (string form) of the current port owner
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param new_process the PID (string form) of the new port owner
+     */
+    probe port__connect(char *process, char *port, char *port_name,
+                        char *new_process);
+
+    /**
+     * Fired when a port is busy (i.e. blocked)
+     *
+     * @param port the port ID of the busy port
+     */
+    probe port__busy(char *port);
+
+    /**
+     * Fired when a port is no longer busy (i.e. no longer blocked)
+     *
+     * @param port the port ID of the not busy port
+     */
+    probe port__not_busy(char *port);
+
+    /* drivers */
+
+    /**
+     * Fired when drivers's "init" callback is called.
+     *
+     * @param name the name of the driver
+     * @param major the major version number
+     * @param minor the minor version number
+     * @param flags the flags argument
+     */
+    probe driver__init(char *name, int major, int minor, int flags);
+
+    /**
+     * Fired when drivers's "start" callback is called.
+     *
+     * @param process the PID (string form) of the calling process
+     * @param name the name of the driver
+     * @param port the Port (string form) of the driver's port
+     */
+     probe driver__start(char *process, char *name, char *port);
+
+    /**
+     * Fired when drivers's "stop" callback is called.
+     *
+     * @param process the PID (string form) of the calling process
+     * @param name the name of the driver
+     * @param port the Port (string form) of the driver's port
+     */
+     probe driver__stop(char *process, char *name, char *port);
+
+    /**
+     * Fired when drivers's "finish" callback is called.
+     *
+     * @param name the name of the driver
+     */
+     probe driver__finish(char *name);
+
+    /**
+     * Fired when drivers's "flush" callback is called.
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__flush(char *process, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "output" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param bytes the number of bytes written
+     */
+    probe driver__output(char *node, char *port, char *port_name, int bytes);
+
+    /**
+     * Fired when driver's "outputv" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param bytes the number of bytes written
+     */
+    probe driver__outputv(char *node, char *port, char *port_name, int bytes);
+
+    /**
+     * Fired when driver's "control" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param command the command #
+     * @param bytes the number of bytes written
+     */
+    probe driver__control(char *node, char *port, char *port_name,
+                          int command, int bytes);
+
+    /**
+     * Fired when driver's "call" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     * @param command the command #
+     * @param bytes the number of bytes written
+     */
+    probe driver__call(char *node, char *port, char *port_name,
+                       int command, int bytes);
+
+    /**
+     * Fired when driver's "event" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__event(char *node, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "ready_input" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__ready_input(char *node, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "read_output" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__ready_output(char *node, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "timeout" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__timeout(char *node, char *port, char *port_name);
+
+    /**
+     * Fired when drivers's "ready_async" callback is called.
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__ready_async(char *process, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "process_exit" callback is called
+     *
+     * @param process the PID (string form)
+     * @param port the Port (string form)
+     * @param port_name the string used when the port was opened
+     */
+    probe driver__process_exit(char *node, char *port, char *port_name);
+
+    /**
+     * Fired when driver's "stop_select" callback is called
+     *
+     * @param name the name of the driver
+     */
+    probe driver__stop_select(char *name);
+
+
+    /* Async driver pool */
+
+    /**
+     * Show the post-add length of the async driver thread pool member's queue.
+     *
+     * NOTE: The port name is not available: additional lock(s) must
+     *       be acquired in order to get the port name safely in an SMP
+     *       environment.  The same is true for the aio__pool_get probe.
+     *
+     * @param port the Port (string form)
+     * @param new queue length
+     */
+    probe aio_pool__add(char *, int);
+
+    /**
+     * Show the post-get length of the async driver thread pool member's queue.
+     *
+     * @param port the Port (string form)
+     * @param new queue length
+     */
+    probe aio_pool__get(char *, int);
+
+    /* Probes for efile_drv.c */
+
+    /**
+     * Entry into the efile_drv.c file I/O driver
+     *
+     * For a list of command numbers used by this driver, see the section
+     * "Guide to probe arguments" in ../../../README.md.  That section
+     * also contains explanation of the various integer and string
+     * arguments that may be present when any particular probe fires.
+     *
+     * NOTE: Not all Linux platforms (using SystemTap) can support
+     *       arguments beyond arg9.
+     *
+     *
+     * TODO: Adding the port string, args[10], is a pain.  Making that
+     *       port string available to all the other efile_drv.c probes
+     *       will be more pain.  Is the pain worth it?  If yes, then
+     *       add them everywhere else and grit our teeth.  If no, then
+     *       rip it out.
+     *
+     * @param thread-id number of the scheduler Pthread                   arg0
+     * @param tag number: {thread-id, tag} uniquely names a driver operation
+     * @param user-tag string                                             arg2
+     * @param command number                                              arg3
+     * @param string argument 1                                           arg4
+     * @param string argument 2                                           arg5
+     * @param integer argument 1                                          arg6
+     * @param integer argument 2                                          arg7
+     * @param integer argument 3                                          arg8
+     * @param integer argument 4                                          arg9
+     * @param port the port ID of the busy port                       args[10]
+     */
+    probe efile_drv__entry(int, int, char *, int, char *, char *,
+                           int64_t, int64_t, int64_t, int64_t, char *);
+
+    /**
+     * Entry into the driver's internal work function.  Computation here
+     * is performed by a async worker pool Pthread.
+     *
+     * @param thread-id number
+     * @param tag number
+     * @param command number
+     */
+    probe efile_drv__int_entry(int, int, int);
+
+    /**
+     * Return from the driver's internal work function.
+     *
+     * @param thread-id number
+     * @param tag number
+     * @param command number
+     */
+    probe efile_drv__int_return(int, int, int);
+
+    /**
+     * Return from the efile_drv.c file I/O driver
+     *
+     * @param thread-id number                                            arg0
+     * @param tag number                                                  arg1
+     * @param user-tag string                                             arg2
+     * @param command number                                              arg3
+     * @param Success? 1 is success, 0 is failure                         arg4
+     * @param If failure, the errno of the error.                         arg5
+     */
+    probe efile_drv__return(int, int, char *, int, int, int);
+
+/*
+ * NOTE:
+ * For formatting int64_t arguments within a D script, see:
+ *
+ *   http://mail.opensolaris.org/pipermail/dtrace-discuss/2006-November/002830.html
+ *   Summary:
+ *       "1) you don't need the 'l' printf() modifiers with DTrace ever"
+ */
+
+/*
+ * NOTE: For file_drv_return + SMP + R14B03 (and perhaps other
+ *       releases), the sched-thread-id will be the same as the
+ *       work-thread-id: erl_async.c's async_main() function
+ *       will call the asynchronous invoke function and then
+ *       immediately call the drivers ready_async function while
+ *       inside the same I/O worker pool thread.
+ *       For R14B03's source, see erl_async.c lines 302-317.
+ */
+};
+
+#pragma D attributes Evolving/Evolving/Common provider erlang provider
+#pragma D attributes Private/Private/Common provider erlang module
+#pragma D attributes Private/Private/Common provider erlang function
+#pragma D attributes Evolving/Evolving/Common provider erlang name
+#pragma D attributes Evolving/Evolving/Common provider erlang args
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index fb1514a147..81f79b8f85 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -43,6 +43,7 @@
 #include "erl_version.h"
 #include "error.h"
 #include "erl_async.h"
+#include "dtrace-wrapper.h"
 
 extern ErlDrvEntry fd_driver_entry;
 extern ErlDrvEntry vanilla_driver_entry;
@@ -180,6 +181,19 @@ typedef struct line_buf_context {
 
 #define LINEBUF_INITIAL 100
 
+#define DTRACE_FORMAT_COMMON_PID_AND_PORT(PID, PORT)         \
+    DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);       \
+    DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);          \
+                                                             \
+    dtrace_pid_str((PID), process_str);                      \
+    dtrace_port_str((PORT), port_str);
+#define DTRACE_FORMAT_COMMON_PROC_AND_PORT(PID, PORT)        \
+    DTRACE_CHARBUF(process_str, DTRACE_TERM_BUF_SIZE);       \
+    DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);          \
+                                                             \
+    dtrace_proc_str((PID), process_str);                     \
+    dtrace_port_str((PORT), port_str);
+
 
 /* The 'number' field in a port now has two parts: the lowest bits
    contain the index in the port table, and the higher bits are a counter
@@ -639,6 +653,10 @@ erts_open_driver(erts_driver_t* driver,	/* Pointer to driver. */
 	    trace_sched_ports_where(port, am_in, am_start);
 	}
 	port->caller = pid;
+        if (DTRACE_ENABLED(driver_start)) {
+            DTRACE_FORMAT_COMMON_PID_AND_PORT(pid, port)
+            DTRACE3(driver_start, process_str, driver->name, port_str);
+        }
 	fpe_was_unmasked = erts_block_fpe();
 	drv_data = (*driver->start)((ErlDrvPort)(port_ix),
 				    name, opts);
@@ -1170,6 +1188,10 @@ int erts_write_to_port(Eterm caller_id, Port *p, Eterm list)
 	ev.size = size;  /* total size */
 	ev.iov = ivp;
 	ev.binv = bvp;
+        if (DTRACE_ENABLED(driver_outputv)) {
+            DTRACE_FORMAT_COMMON_PID_AND_PORT(caller_id, p)
+            DTRACE4(driver_outputv, process_str, port_str, p->name, size);
+        }
 	fpe_was_unmasked = erts_block_fpe();
 	(*drv->outputv)((ErlDrvData)p->drv_data, &ev);
 	erts_unblock_fpe(fpe_was_unmasked);
@@ -1189,8 +1211,17 @@ int erts_write_to_port(Eterm caller_id, Port *p, Eterm list)
 	buf = erts_alloc(ERTS_ALC_T_TMP, size+1);
 	r = io_list_to_buf(list, buf, size);
 
+	if(DTRACE_ENABLED(port_command)) {
+            DTRACE_FORMAT_COMMON_PID_AND_PORT(caller_id, p)
+	    DTRACE4(port_command, process_str, port_str, p->name, "command");
+	}
+
 	if (r >= 0) {
 	    size -= r;
+            if (DTRACE_ENABLED(driver_output)) {
+                DTRACE_FORMAT_COMMON_PID_AND_PORT(caller_id, p)
+                DTRACE4(driver_output, process_str, port_str, p->name, size);
+            }
 	    fpe_was_unmasked = erts_block_fpe();
 	    (*drv->output)((ErlDrvData)p->drv_data, buf, size);
 	    erts_unblock_fpe(fpe_was_unmasked);
@@ -1214,6 +1245,10 @@ int erts_write_to_port(Eterm caller_id, Port *p, Eterm list)
 	     */
 	    buf = erts_alloc(ERTS_ALC_T_TMP, size+1); 
 	    r = io_list_to_buf(list, buf, size);
+            if (DTRACE_ENABLED(driver_output)) {
+                DTRACE_FORMAT_COMMON_PID_AND_PORT(caller_id, p)
+                DTRACE4(driver_output, process_str, port_str, p->name, size);
+            }
 	    fpe_was_unmasked = erts_block_fpe();
 	    (*drv->output)((ErlDrvData)p->drv_data, buf, size);
 	    erts_unblock_fpe(fpe_was_unmasked);
@@ -1810,6 +1845,10 @@ static void flush_port(Port *p)
     ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(p));
 
     if (p->drv_ptr->flush != NULL) {
+        if (DTRACE_ENABLED(driver_flush)) {
+            DTRACE_FORMAT_COMMON_PID_AND_PORT(p->connected, p)
+            DTRACE3(driver_flush, process_str, port_str, p->name);
+        }
         if (IS_TRACED_FL(p, F_TRACE_SCHED_PORTS)) {
 	    trace_sched_ports_where(p, am_in, am_flush);
 	}
@@ -1865,6 +1904,10 @@ terminate_port(Port *prt)
     drv = prt->drv_ptr;
     if ((drv != NULL) && (drv->stop != NULL)) {
 	int fpe_was_unmasked = erts_block_fpe();
+        if (DTRACE_ENABLED(driver_stop)) {
+            DTRACE_FORMAT_COMMON_PID_AND_PORT(prt->connected, prt)
+            DTRACE3(driver_stop, process_str, drv->name, port_str);
+        }
 	(*drv->stop)((ErlDrvData)prt->drv_data);
 	erts_unblock_fpe(fpe_was_unmasked);
 #ifdef ERTS_SMP
@@ -2026,6 +2069,17 @@ erts_do_exit_port(Port *p, Eterm from, Eterm reason)
 
    rreason = (reason == am_kill) ? am_killed : reason;
 
+   if (DTRACE_ENABLED(port_exit)) {
+       DTRACE_CHARBUF(from_str, DTRACE_TERM_BUF_SIZE);
+       DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);
+       DTRACE_CHARBUF(rreason_str, 64);
+
+       erts_snprintf(from_str, sizeof(from_str), "%T", from);
+       dtrace_port_str(p, port_str);
+       erts_snprintf(rreason_str, sizeof(rreason_str), "%T", rreason);
+       DTRACE4(port_exit, from_str, port_str, p->name, rreason_str);
+   }
+
    if ((p->status & (ERTS_PORT_SFLGS_DEAD
 		     | ERTS_PORT_SFLG_EXITING
 		     | ERTS_PORT_SFLG_IMMORTAL))
@@ -2126,6 +2180,11 @@ void erts_port_command(Process *proc,
 	    if (tp[2] == am_close) {
 		erts_port_status_bor_set(port, ERTS_PORT_SFLG_SEND_CLOSED);
 		erts_do_exit_port(port, pid, am_normal);
+
+		if(DTRACE_ENABLED(port_command)) {
+                    DTRACE_FORMAT_COMMON_PROC_AND_PORT(proc, port)
+		    DTRACE4(port_command, process_str, port_str, port->name, "close");
+		}
 		goto done;
 	    } else if (is_tuple_arity(tp[2], 2)) {
 		tp = tuple_val(tp[2]);
@@ -2133,6 +2192,10 @@ void erts_port_command(Process *proc,
 		    if (erts_write_to_port(caller_id, port, tp[2]) == 0)
 			goto done;
 		} else if ((tp[1] == am_connect) && is_internal_pid(tp[2])) {
+		    if(DTRACE_ENABLED(port_command)) {
+                        DTRACE_FORMAT_COMMON_PROC_AND_PORT(proc, port)
+			DTRACE4(port_command, process_str, port_str, port->name, "connect");
+		    }
 		    port->connected = tp[2];
 		    deliver_result(port->id, pid, am_connected);
 		    goto done;
@@ -2235,6 +2298,13 @@ erts_port_control(Process* p, Port* prt, Uint command, Eterm iolist)
     erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
     ERTS_SMP_CHK_NO_PROC_LOCKS;
 
+    if (DTRACE_ENABLED(port_control) || DTRACE_ENABLED(driver_control)) {
+        DTRACE_FORMAT_COMMON_PROC_AND_PORT(p, prt);
+        DTRACE4(port_control, process_str, port_str, prt->name, command);
+        DTRACE5(driver_control, process_str, port_str, prt->name,
+                command, to_len);
+    }
+
     /*
      * Call the port's control routine.
      */
@@ -2375,6 +2445,8 @@ print_port_info(int to, void *arg, int i)
 void
 set_busy_port(ErlDrvPort port_num, int on)
 {
+    DTRACE_CHARBUF(port_str, 16);
+
     ERTS_SMP_CHK_NO_PROC_LOCKS;
 
     ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(&erts_port[port_num]));
@@ -2382,12 +2454,22 @@ set_busy_port(ErlDrvPort port_num, int on)
     if (on) {
         erts_port_status_bor_set(&erts_port[port_num],
 				 ERTS_PORT_SFLG_PORT_BUSY);
+        if (DTRACE_ENABLED(port_busy)) {
+            erts_snprintf(port_str, sizeof(port_str),
+                          "%T", erts_port[port_num].id);
+            DTRACE1(port_busy, port_str);
+        }
     } else {
         ErtsProcList* plp = erts_port[port_num].suspended;
         erts_port_status_band_set(&erts_port[port_num],
 				  ~ERTS_PORT_SFLG_PORT_BUSY);
         erts_port[port_num].suspended = NULL;
 
+        if (DTRACE_ENABLED(port_not_busy)) {
+            erts_snprintf(port_str, sizeof(port_str),
+                          "%T", erts_port[port_num].id);
+            DTRACE1(port_not_busy, port_str);
+        }
 	if (erts_port[port_num].dist_entry) {
 	    /*
 	     * Processes suspended on distribution ports are
@@ -2405,6 +2487,26 @@ set_busy_port(ErlDrvPort port_num, int on)
 	 */
 
         if (plp) {
+            /*
+             * Hrm, for blocked dist ports, plp always seems to be NULL.
+             * That's not so fun.
+             * Well, another way to get the same info is using a D
+             * script to correlate an earlier process-port_blocked+pid
+             * event with a later process-scheduled event.  That's
+             * subject to the multi-CPU races with how events are
+             * handled, but hey, that way works most of the time.
+             */
+            if (DTRACE_ENABLED(process_port_unblocked)) {
+                DTRACE_CHARBUF(pid_str, 16);
+                ErtsProcList* plp2 = plp;
+
+                erts_snprintf(port_str, sizeof(port_str),
+                             "%T", erts_port[port_num]);
+                while (plp2 != NULL) {
+                    erts_snprintf(pid_str, sizeof(pid_str), "%T", plp2->pid);
+                    DTRACE2(process_port_unblocked, pid_str, port_str);
+                }
+            }
             /* First proc should be resumed last */
 	    if (plp->next) {
 		erts_resume_processes(plp->next);
@@ -2451,6 +2553,12 @@ void erts_raw_port_command(Port* p, byte* buf, Uint len)
 		 p->drv_ptr->name ? p->drv_ptr->name : "unknown");
 
     p->caller = NIL;
+    if (DTRACE_ENABLED(driver_output)) {
+        DTRACE_CHARBUF(port_str, DTRACE_TERM_BUF_SIZE);
+
+        dtrace_port_str(p, port_str);
+        DTRACE4(driver_output, "-raw-", port_str, p->name, len);
+    }
     fpe_was_unmasked = erts_block_fpe();
     (*p->drv_ptr->output)((ErlDrvData)p->drv_data, (char*) buf, (int) len);
     erts_unblock_fpe(fpe_was_unmasked);
@@ -2466,6 +2574,10 @@ int async_ready(Port *p, void* data)
 	ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(p));
 	ASSERT(!(p->status & ERTS_PORT_SFLGS_DEAD));
 	if (p->drv_ptr->ready_async != NULL) {
+            if (DTRACE_ENABLED(driver_ready_async)) {
+                DTRACE_FORMAT_COMMON_PID_AND_PORT(p->connected, p)
+                DTRACE3(driver_ready_async, process_str, port_str, p->name);
+            }
 	    (*p->drv_ptr->ready_async)((ErlDrvData)p->drv_data, data);
 	    need_free = 0;
 #ifdef ERTS_SMP
@@ -4441,6 +4553,10 @@ void erts_fire_port_monitor(Port *prt, Eterm ref)
     ASSERT(callback != NULL);
     ref_to_driver_monitor(ref,&drv_monitor);
     DRV_MONITOR_UNLOCK_PDL(prt);
+    if (DTRACE_ENABLED(driver_process_exit)) {
+        DTRACE_FORMAT_COMMON_PID_AND_PORT(prt->connected, prt)
+        DTRACE3(driver_process_exit, process_str, port_str, prt->name);
+    }
     fpe_was_unmasked = erts_block_fpe();
     (*callback)((ErlDrvData) (prt->drv_data), &drv_monitor);
     erts_unblock_fpe(fpe_was_unmasked);
@@ -4884,6 +5000,8 @@ init_driver(erts_driver_t *drv, ErlDrvEntry *de, DE_Handle *handle)
     else {
 	int res;
 	int fpe_was_unmasked = erts_block_fpe();
+        DTRACE4(driver_init, drv->name, drv->version.major, drv->version.minor,
+                drv->flags);
 	res = (*de->init)();
 	erts_unblock_fpe(fpe_was_unmasked);
 	return res;
diff --git a/erts/emulator/sys/common/erl_check_io.c b/erts/emulator/sys/common/erl_check_io.c
index 23a4bf1b04..cb7ef95f00 100644
--- a/erts/emulator/sys/common/erl_check_io.c
+++ b/erts/emulator/sys/common/erl_check_io.c
@@ -36,6 +36,7 @@
 #include "global.h"
 #include "erl_check_io.h"
 #include "erl_thr_progress.h"
+#include "dtrace-wrapper.h"
 
 #ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
 #  define ERTS_DRV_EV_STATE_EXTRA_SIZE 128
@@ -314,6 +315,7 @@ forget_removed(struct pollset_info* psi)
 	erts_smp_mtx_unlock(mtx);
 	if (drv_ptr) {
 	    int was_unmasked = erts_block_fpe();
+	    DTRACE1(driver_stop_select, drv_ptr->name);
 	    (*drv_ptr->stop_select) ((ErlDrvEvent) fd, NULL);
 	    erts_unblock_fpe(was_unmasked);
 	    if (drv_ptr->handle) {
@@ -496,6 +498,7 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
     ErtsDrvEventState *state;
     int wake_poller;
     int ret;
+    DTRACE_CHARBUF(name, 64);
     
     ERTS_SMP_LC_ASSERT(erts_drvport2port(ix)
 		       && erts_lc_is_port_locked(erts_drvport2port(ix)));
@@ -525,6 +528,8 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
 	if (IS_FD_UNKNOWN(state)) {
 	    /* fast track to stop_select callback */
 	    stop_select_fn = erts_drvport2port(ix)->drv_ptr->stop_select;
+	    strncpy(name, erts_drvport2port(ix)->drv_ptr->name, sizeof(name)-1);
+	    name[sizeof(name)-1] = '\0';
 	    ret = 0;
 	    goto done_unknown;
 	}
@@ -661,6 +666,8 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
 		    /* Safe to close fd now as it is not in pollset
 		       or there was no need to eject fd (kernel poll) */
 		    stop_select_fn = drv_ptr->stop_select;
+		    strncpy(name, erts_drvport2port(ix)->drv_ptr->name, sizeof(name)-1);
+		    name[sizeof(name)-1] = '\0';
 		}
 		else {
 		    /* Not safe to close fd, postpone stop_select callback. */
@@ -686,6 +693,7 @@ done_unknown:
     erts_smp_mtx_unlock(fd_mtx(fd));
     if (stop_select_fn) {
 	int was_unmasked = erts_block_fpe();
+	DTRACE1(driver_stop_select, name);
 	(*stop_select_fn)(e, NULL);
 	erts_unblock_fpe(was_unmasked);
     }
diff --git a/erts/lib_src/common/erl_printf.c b/erts/lib_src/common/erl_printf.c
index 108a8bb531..afb9c0abb7 100644
--- a/erts/lib_src/common/erl_printf.c
+++ b/erts/lib_src/common/erl_printf.c
@@ -176,16 +176,18 @@ write_sn(void *vwsnap, char* buf, size_t len)
     write_sn_arg_t *wsnap = (write_sn_arg_t *) vwsnap;
     ASSERT(wsnap);
     ASSERT(len > 0);
+    int rv = 0;
     if (wsnap->len > 0) {
 	size_t sz = len;
 	if (sz >= wsnap->len)
 	    sz = wsnap->len;
+	rv = (int)sz;
 	memcpy((void *) wsnap->buf, (void *) buf, sz);
 	wsnap->buf += sz;
 	wsnap->len -= sz;
 	return sz;
     }
-    return 0;
+    return rv;
 }
 
 static int