proc-begin3.patch

diff --git a/NEWS b/NEWS
index 303a1075e..c927c0f69 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,9 @@
 
 * What's new in version 4.2, 2019-11-18
 
+- The process(EXE).begin probe handlers are now always triggered for
+  already-running target processes.
+
 - Initial support for multi-dimensional supports has been added to
   the stapbpf backend. Note that these arrays cannot be iterated upon
   with a foreach loop.
diff --git a/runtime/linux/debug.h b/runtime/linux/debug.h
index e23ee96e7..d2ab9e8db 100644
--- a/runtime/linux/debug.h
+++ b/runtime/linux/debug.h
@@ -73,6 +73,17 @@
 #define dbug_unwind(level, args...) ;
 #endif
 
+
+#ifdef DEBUG_TASK_FINDER
+#define dbug_task(level, args...) do {                              \
+		if ((level) <= DEBUG_TASK_FINDER)		    \
+			_stp_dbug(__FUNCTION__, __LINE__, args);    \
+	} while (0)
+#else
+#define dbug_task(level, args...) ;
+#endif
+
+
 #if defined(DEBUG_TASK_FINDER_VMA)
 #define dbug_task_vma(level, args...) do {                                     \
                if ((level) <= DEBUG_TASK_FINDER_VMA)                               \
diff --git a/runtime/linux/task_finder2.c b/runtime/linux/task_finder2.c
index 6f5d637da..d4d811834 100644
--- a/runtime/linux/task_finder2.c
+++ b/runtime/linux/task_finder2.c
@@ -35,10 +35,10 @@ static atomic_t __stp_attach_count = ATOMIC_INIT (0);
 
 #define debug_task_finder_attach() (atomic_inc(&__stp_attach_count))
 #define debug_task_finder_detach() (atomic_dec(&__stp_attach_count))
-#define debug_task_finder_report()					\
-    (printk(KERN_ERR "%s:%d - attach count: %d, inuse count: %d\n",	\
-	    __FUNCTION__, __LINE__, atomic_read(&__stp_attach_count),	\
-	    atomic_read(&__stp_inuse_count)))
+#define debug_task_finder_report()                      \
+    dbug_task(1, "attach count: %d, inuse count: %d\n",	\
+	    atomic_read(&__stp_attach_count),           \
+	    atomic_read(&__stp_inuse_count))
 #else
 #define debug_task_finder_attach()	/* empty */
 #define debug_task_finder_detach()	/* empty */
@@ -532,6 +532,8 @@ __stp_utrace_attach(struct task_struct *tsk,
 	}
 	else {
 		rc = utrace_set_events(tsk, engine, event_flags);
+		dbug_task(2, "utrace_set_events(%lu) returned %d", event_flags,
+			  rc);
 		if (rc == -EINPROGRESS) {
 			/*
 			 * It's running our callback, so we have to
@@ -553,6 +555,7 @@ __stp_utrace_attach(struct task_struct *tsk,
 
 			if (action != UTRACE_RESUME) {
 				rc = utrace_control(tsk, engine, action);
+				dbug_task(2, "utrace_control(%d) returned %d", action, rc);
 				/* If utrace_control() returns
 				 * EINPROGRESS when we're trying to
 				 * stop/interrupt, that means the task
@@ -588,6 +591,8 @@ __stp_call_callbacks(struct stap_task_finder_target *tgt,
 	struct list_head *cb_node;
 	int rc;
 
+	dbug_task(2, "entering tgt=%p tsk=%p pid=%d", tgt, tsk, tsk ? tsk->tgid : -1);
+
 	if (tgt == NULL || tsk == NULL)
 		return;
 
@@ -600,6 +605,13 @@ __stp_call_callbacks(struct stap_task_finder_target *tgt,
 			continue;
 
 		rc = cb_tgt->callback(cb_tgt, tsk, register_p, process_p);
+
+		dbug_task(2, "tgt %s callback returned %d (proc=%s pid=%d, "
+			  "pathlen=%d, engine-attached=%d)",
+			  (cb_tgt->purpose?:""), rc, cb_tgt->procname,
+			  cb_tgt->pid, (int) cb_tgt->pathlen,
+			  cb_tgt->engine_attached);
+
 		if (rc != 0) {
 			_stp_warn("task_finder %s%scallback for task %d failed: %d",
                                   (cb_tgt->purpose?:""), (cb_tgt->purpose?" ":""),
@@ -835,7 +847,11 @@ __stp_utrace_attach_match_filename(struct task_struct *tsk,
 		else if (tgt->pathlen > 0
 			 && (tgt->pathlen != filelen
 			     || strcmp(tgt->procname, filename) != 0))
+		{
+			dbug_task(2, "target path NOT matched: [%s] != [%s]",
+			          tgt->procname, filename);
 			continue;
+		}
 		/* Ignore pid-based target, they were handled at startup. */
 		else if (tgt->pid != 0)
 			continue;
@@ -1660,6 +1676,10 @@ stap_start_task_finder(void)
 		rc = __stp_utrace_attach(tsk, &__stp_utrace_task_finder_ops, 0,
 					 __STP_TASK_FINDER_EVENTS,
 					 UTRACE_RESUME);
+
+		dbug_task(2, "__stp_utrace_attach() for pid %d returned %d",
+		          tsk->tgid, rc);
+
 		if (rc == EPERM) {
 			/* Ignore EPERM errors, which mean this wasn't
 			 * a thread we can attach to. */
@@ -1724,7 +1744,11 @@ stap_start_task_finder(void)
 			else if (tgt->pathlen > 0
 				 && (tgt->pathlen != mmpathlen
 				     || strcmp(tgt->procname, mmpath) != 0))
+			{
+				dbug_task(2, "target path not matched: [%s] != [%s]",
+					  tgt->procname, mmpath);
 				continue;
+			}
 			/* pid-based target */
 			else if (tgt->pid != 0 && tgt->pid != tsk->pid)
 				continue;
@@ -1747,6 +1771,10 @@ stap_start_task_finder(void)
 			rc = __stp_utrace_attach(tsk, &tgt->ops, tgt,
 						 __STP_ATTACHED_TASK_EVENTS,
 						 UTRACE_STOP);
+
+			dbug_task(2, "__stp_utrace_attach() for %d returned %d", tsk->tgid,
+				  rc);
+
 			if (rc != 0 && rc != EPERM)
 				goto stf_err;
 			rc = 0;		/* ignore EPERM */
@@ -1771,18 +1799,13 @@ stap_task_finder_post_init(void)
 		return;
 	}
 
-#ifdef DEBUG_TASK_FINDER
-	printk(KERN_ERR "%s:%d - entry.\n", __FUNCTION__, __LINE__);
-#endif
+	dbug_task(2, "entry.");
 	rcu_read_lock();
 	do_each_thread(grp, tsk) {
 		struct list_head *tgt_node;
 
 		if (atomic_read(&__stp_task_finder_state) != __STP_TF_RUNNING) {
-#ifdef DEBUG_TASK_FINDER
-			printk(KERN_ERR "%s:%d - exiting early...\n",
-			       __FUNCTION__, __LINE__);
-#endif
+			dbug_task(2, "exiting early...");
 			break;
 		}
 
@@ -1824,6 +1847,10 @@ stap_task_finder_post_init(void)
 					_stp_error("utrace_control returned error %d on pid %d",
 						   rc, (int)tsk->pid);
 				}
+
+				dbug_task(2, "utrace_control(UTRACE_INTERRUPT) for pid %d "
+					  	  "returned %d (%d)", tsk->pid, rc, -EINPROGRESS);
+
 				utrace_engine_put(engine);
 
 				/* Since we only need to interrupt
@@ -1835,9 +1862,7 @@ stap_task_finder_post_init(void)
 	} while_each_thread(grp, tsk);
 	rcu_read_unlock();
 	atomic_set(&__stp_task_finder_complete, 1);
-#ifdef DEBUG_TASK_FINDER
-	printk(KERN_ERR "%s:%d - exit.\n", __FUNCTION__, __LINE__);
-#endif
+	dbug_task(2, "exit.");
 	return;
 }
 
diff --git a/tapset-been.cxx b/tapset-been.cxx
index 61b3b18a3..1107d3e76 100644
--- a/tapset-been.cxx
+++ b/tapset-been.cxx
@@ -149,7 +149,7 @@ be_derived_probe_group::emit_module_decls (systemtap_session& s)
 
   s.op->newline() << "static void enter_be_probe (struct stap_be_probe *stp) {";
   s.op->indent(1);
-  common_probe_entryfn_prologue (s, "stp->state", "stp->probe",
+  common_probe_entryfn_prologue (s, "stp->state", "", "stp->probe",
 				 "stp_probe_type_been", false);
   s.op->newline() << "(*stp->probe->ph) (c);";
   common_probe_entryfn_epilogue (s, false, otf_safe_context(s));
diff --git a/tapset-itrace.cxx b/tapset-itrace.cxx
index 4682e7674..0a262076c 100644
--- a/tapset-itrace.cxx
+++ b/tapset-itrace.cxx
@@ -199,7 +199,7 @@ itrace_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->newline() << "static void enter_itrace_probe(struct stap_itrace_probe *p, struct pt_regs *regs, void *data) {";
   s.op->indent(1);
 
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "p->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "p->probe",
 				 "stp_probe_type_itrace");
   s.op->newline() << "c->uregs = regs;";
   s.op->newline() << "c->user_mode_p = 1;";
diff --git a/tapset-mark.cxx b/tapset-mark.cxx
index 2dec501c8..5a48eaa76 100644
--- a/tapset-mark.cxx
+++ b/tapset-mark.cxx
@@ -509,7 +509,7 @@ mark_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->newline();
   s.op->newline() << "static void enter_marker_probe (void *probe_data, void *call_data, const char *fmt, va_list *args) {";
   s.op->newline(1) << "struct stap_marker_probe *smp = (struct stap_marker_probe *)probe_data;";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "smp->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "smp->probe",
 				 "stp_probe_type_marker");
   s.op->newline() << "c->ips.kmark.marker_name = smp->name;";
   s.op->newline() << "c->ips.kmark.marker_format = smp->format;";
diff --git a/tapset-netfilter.cxx b/tapset-netfilter.cxx
index 1c6952e1f..a6ae5909d 100644
--- a/tapset-netfilter.cxx
+++ b/tapset-netfilter.cxx
@@ -313,7 +313,7 @@ netfilter_derived_probe_group::emit_module_decls (systemtap_session& s)
       s.op->newline() << "#elif defined(STAPCONF_NETFILTER_V41)";
       s.op->newline() << "int (*nf_okfn)(struct sock *, struct sk_buff *) = nf_state->okfn;";
       s.op->newline() << "#endif";
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "stp",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "stp",
                                      "stp_probe_type_netfilter",
                                      false);
 
diff --git a/tapset-perfmon.cxx b/tapset-perfmon.cxx
index 11dbbd32b..2b9f5ad42 100644
--- a/tapset-perfmon.cxx
+++ b/tapset-perfmon.cxx
@@ -235,7 +235,7 @@ perf_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->newline() << "static void handle_perf_probe (unsigned i, struct pt_regs *regs)";
   s.op->newline() << "{";
   s.op->newline(1) << "struct stap_perf_probe* stp = & stap_perf_probes [i];";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "stp->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "stp->probe",
 				 "stp_probe_type_perf");
   s.op->newline() << "if (user_mode(regs)) {";
   s.op->newline(1)<< "c->user_mode_p = 1;";
diff --git a/tapset-procfs.cxx b/tapset-procfs.cxx
index c39f20fcb..c5087afcb 100644
--- a/tapset-procfs.cxx
+++ b/tapset-procfs.cxx
@@ -366,7 +366,7 @@ procfs_derived_probe_group::emit_module_decls (systemtap_session& s)
     {
       s.op->newline() << "struct _stp_procfs_data pdata;";
 
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "",
 				     "spp->read_probe",
 				     "stp_probe_type_procfs");
 
@@ -412,7 +412,7 @@ procfs_derived_probe_group::emit_module_decls (systemtap_session& s)
     {
       s.op->newline() << "struct _stp_procfs_data pdata;";
 
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "",
 				     "spp->write_probes[0]",
 				     "stp_probe_type_procfs");
 
diff --git a/tapset-timers.cxx b/tapset-timers.cxx
index 8dd00a1b9..4949b6e14 100644
--- a/tapset-timers.cxx
+++ b/tapset-timers.cxx
@@ -136,7 +136,7 @@ timer_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->line() << ");";
   s.op->newline(-1) << "{";
   s.op->indent(1);
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "stp->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "stp->probe",
 				 "stp_probe_type_timer");
   s.op->newline() << "(*stp->probe->ph) (c);";
   common_probe_entryfn_epilogue (s, true, otf_safe_context(s));
@@ -293,7 +293,7 @@ hrtimer_derived_probe_group::emit_module_decls (systemtap_session& s)
 
       s.op->newline() << "{";
       s.op->indent(1);
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "stp->probe",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "stp->probe",
 				     "stp_probe_type_hrtimer");
       s.op->newline() << "(*stp->probe->ph) (c);";
       common_probe_entryfn_epilogue (s, true, otf_safe_context(s));
@@ -315,7 +315,8 @@ hrtimer_derived_probe_group::emit_module_decls (systemtap_session& s)
 
       s.op->newline() << "{";
       s.op->indent(1);
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "stp->probe",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "",
+                                     "stp->probe",
 				     "stp_probe_type_hrtimer");
       s.op->newline() << "(*stp->probe->ph) (c);";
       common_probe_entryfn_epilogue (s, true, otf_safe_context(s));
@@ -483,7 +484,7 @@ profile_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->newline() << "static void enter_all_profile_probes (struct pt_regs *regs) {";
   s.op->newline(1) << "const struct stap_probe * probe = "
                    << common_probe_init (probes[0]) << ";";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "probe",
 				 "stp_probe_type_profile_timer");
   // Timer interrupts save all registers, so if the interrupt happened
   // in user space we can rely on it being the full user pt_regs.
diff --git a/tapset-utrace.cxx b/tapset-utrace.cxx
index 2b644843a..f85607398 100644
--- a/tapset-utrace.cxx
+++ b/tapset-utrace.cxx
@@ -862,10 +862,13 @@ utrace_derived_probe_group::emit_module_linux_decls (systemtap_session& s)
       s.op->newline() << "static void stap_utrace_probe_handler(struct task_struct *tsk, struct stap_utrace_probe *p) {";
       s.op->indent(1);
 
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "p->probe",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING",
+                                     "STAP_SESSION_STARTING",
+                                     "p->probe",
 				     "stp_probe_type_utrace");
 
       // call probe function
+      s.op->newline() << "dbug_task(2, \"calling UDPF probe function\");";
       s.op->newline() << "(*p->probe->ph) (c);";
       common_probe_entryfn_epilogue (s, true, otf_safe_context(s));
 
@@ -889,7 +892,7 @@ utrace_derived_probe_group::emit_module_linux_decls (systemtap_session& s)
       s.op->indent(1);
       s.op->newline() << "struct stap_utrace_probe *p = (struct stap_utrace_probe *)engine->data;";
 
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "p->probe",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "p->probe",
 				     "stp_probe_type_utrace_syscall");
       s.op->newline() << "c->uregs = regs;";
       s.op->newline() << "c->user_mode_p = 1;";
@@ -914,6 +917,10 @@ utrace_derived_probe_group::emit_module_linux_decls (systemtap_session& s)
   s.op->newline() << "int rc = 0;";
   s.op->newline() << "struct stap_utrace_probe *p = container_of(tgt, struct stap_utrace_probe, tgt);";
   s.op->newline() << "struct utrace_engine *engine;";
+  s.op->newline() << "dbug_task(2, \"utrace probe cb: register_p=%d "
+    "process_p=%d, p->flags=%x (begin: %d, thr begin: %d)\", "
+    "register_p, process_p, (unsigned) p->flags, UDPF_BEGIN, "
+    "UDPF_THREAD_BEGIN);";
 
   s.op->newline() << "if (register_p) {";
   s.op->indent(1);
@@ -1176,7 +1183,7 @@ utrace_derived_probe_group::emit_module_dyninst_decls (systemtap_session& s)
                   << "(uint64_t index, struct pt_regs *regs) {";
   s.op->newline(1) << "struct stapdu_probe *sup = &stapdu_probes[index];";
 
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sup->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sup->probe",
                                  "stp_probe_type_utrace");
   s.op->newline() << "c->uregs = regs ?: &stapdu_dummy_uregs;";
   s.op->newline() << "c->user_mode_p = 1;";
diff --git a/tapsets.cxx b/tapsets.cxx
index b83960a2e..68ec74b43 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -91,7 +91,7 @@ common_probe_init (derived_probe* p)
 
 void
 common_probe_entryfn_prologue (systemtap_session& s,
-			       string statestr, string probe,
+			       string statestr, string statestr2, string probe,
 			       string probe_type, bool overload_processing,
 			       void (*declaration_callback)(systemtap_session& s, void *data),
 			       void (*pre_context_callback)(systemtap_session& s, void *data),
@@ -159,9 +159,20 @@ common_probe_entryfn_prologue (systemtap_session& s,
       s.op->newline(-1) << "}";
     }
 
-  s.op->newline() << "if (atomic_read (session_state()) != " << statestr << ")";
-  s.op->newline(1) << "goto probe_epilogue;";
-  s.op->indent(-1);
+  s.op->newline() << "{";
+  s.op->newline(1) << "unsigned sess_state = atomic_read (session_state());";
+  s.op->newline() << "#ifdef DEBUG_PROBES";
+  s.op->newline() << "_stp_dbug(__FUNCTION__, __LINE__, \"session state: %d, "
+    "expecting " << statestr << " (%d)"
+    << (statestr2.empty() ? "" : string(" or ") + statestr2 + " (%d)")
+    << "\", sess_state, " << statestr
+    << (statestr2.empty() ? "" : string(", ") + statestr2)  << ");";
+  s.op->newline() << "#endif";
+  s.op->newline() << "if (sess_state != " << statestr
+    << (statestr2.empty() ? "" : string(" && sess_state != ") + statestr2)
+    << ")";
+  s.op->newline() << "goto probe_epilogue;";
+  s.op->newline(-1) << "}";
 
   if (pre_context_callback)
     {
@@ -6079,7 +6090,7 @@ generic_kprobe_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->line() << "kprobe_idx:0)"; // NB: at least we avoid memory corruption
   // XXX: it would be nice to give a more verbose error though; BUG_ON later?
   s.op->line() << "];";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "skp->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "skp->probe",
 				 "stp_probe_type_kprobe");
   s.op->newline() << "c->kregs = regs;";
 
@@ -6116,7 +6127,7 @@ generic_kprobe_derived_probe_group::emit_module_decls (systemtap_session& s)
   s.op->newline() << "const struct stap_probe *sp = entry ? skp->entry_probe : skp->probe;";
   s.op->newline() << "if (sp) {";
   s.op->indent(1);
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sp",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sp",
 				 "stp_probe_type_kretprobe");
   s.op->newline() << "c->kregs = regs;";
 
@@ -9465,7 +9476,7 @@ uprobe_derived_probe_group::emit_module_utrace_decls (systemtap_session& s)
   s.op->newline() << "static void enter_uprobe_probe (struct uprobe *inst, struct pt_regs *regs) {";
   s.op->newline(1) << "struct stap_uprobe *sup = container_of(inst, struct stap_uprobe, up);";
   s.op->newline() << "const struct stap_uprobe_spec *sups = &stap_uprobe_specs [sup->spec_index];";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sups->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sups->probe",
 				 "stp_probe_type_uprobe", true,
 				 udpg_entryfn_prologue_declaration_callback,
 				 udpg_entryfn_prologue_pre_context_callback,
@@ -9500,7 +9511,7 @@ uprobe_derived_probe_group::emit_module_utrace_decls (systemtap_session& s)
   s.op->newline() << "static void enter_uretprobe_probe (struct uretprobe_instance *inst, struct pt_regs *regs) {";
   s.op->newline(1) << "struct stap_uprobe *sup = container_of(inst->rp, struct stap_uprobe, urp);";
   s.op->newline() << "const struct stap_uprobe_spec *sups = &stap_uprobe_specs [sup->spec_index];";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sups->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sups->probe",
 				 "stp_probe_type_uretprobe", true,
 				 udpg_entryfn_prologue_declaration_callback,
 				 udpg_entryfn_prologue_pre_context_callback,
@@ -9664,7 +9675,7 @@ uprobe_derived_probe_group::emit_module_inode_decls (systemtap_session& s)
 
   // Since we're sharing the entry function, we have to dynamically choose the probe_type
   string probe_type = "(sup->return_p ? stp_probe_type_uretprobe : stp_probe_type_uprobe)";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sup->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sup->probe",
                                  probe_type, true,
 				 udpg_entryfn_prologue_declaration_callback,
 				 udpg_entryfn_prologue_pre_context_callback,
@@ -9857,7 +9868,7 @@ uprobe_derived_probe_group::emit_module_dyninst_decls (systemtap_session& s)
   // Since we're sharing the entry function, we have to dynamically choose the probe_type
   string probe_type = "((sup->flags & STAPDYN_PROBE_FLAG_RETURN) ?"
                       " stp_probe_type_uretprobe : stp_probe_type_uprobe)";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "sup->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "sup->probe",
                                  probe_type);
 
   s.op->newline() << "c->uregs = regs ?: &stapdu_dummy_uregs;";
@@ -10546,7 +10557,7 @@ hwbkpt_derived_probe_group::emit_module_decls (systemtap_session& s)
   // XXX: why not match stap_hwbkpt_ret_array[i] against bp instead?
   s.op->newline() << "if (bp->attr.bp_addr==hp->bp_addr && bp->attr.bp_type==hp->bp_type && bp->attr.bp_len==hp->bp_len) {";
   s.op->newline(1) << "struct stap_hwbkpt_probe *skp = &stap_hwbkpt_probes[i];";
-  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "skp->probe",
+  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "skp->probe",
 				 "stp_probe_type_hwbkpt");
   s.op->newline() << "if (user_mode(regs)) {";
   s.op->newline(1)<< "c->user_mode_p = 1;";
@@ -11866,7 +11877,7 @@ tracepoint_derived_probe_group::emit_module_decls (systemtap_session& s)
       s.op->newline() << "{";
       s.op->newline(1) << "const struct stap_probe * const probe = "
                        << common_probe_init (p) << ";";
-      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "probe",
+      common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "", "probe",
 				     "stp_probe_type_tracepoint");
       s.op->newline() << "c->ips.tp.tracepoint_system = "
                       << lex_cast_qstring (p->tracepoint_system)
diff --git a/tapsets.h b/tapsets.h
index b52c35c21..2a11ebd6f 100644
--- a/tapsets.h
+++ b/tapsets.h
@@ -21,6 +21,7 @@ void register_standard_tapsets(systemtap_session& sess);
 std::vector<derived_probe_group*> all_session_groups(systemtap_session& s);
 std::string common_probe_init (derived_probe* p);
 void common_probe_entryfn_prologue (systemtap_session& s, std::string statestr,
+                                    std::string statestr2,
 				    std::string probe, std::string probe_type,
 				    bool overload_processing = true,
 				    void (*declaration_callback)(systemtap_session& s, void* data) = NULL,