Add support for progress events in OpenMP

Two new events are added (Ppp and Pps) which define the Progressing and
Stalled states respectively. A new pseudo-state Idle is shown in the
view when no thread is running.

cfg/cpu/openmp/breakdown.cfg

@@ -39,6 +39,6 @@ window_pixel_size 1
 window_labels_to_draw 1
 window_selected_functions { 14, { {cpu, Active Thd}, {appl, Adding}, {task, Adding}, {thread, Last Evt Val}, {node, Adding}, {system, Adding}, {workload, Adding}, {from_obj, All}, {to_obj, All}, {tag_msg, All}, {size_msg, All}, {bw_msg, All}, {evt_type, =}, {evt_value, All} } }
 window_compose_functions { 9, { {compose_cpu, As Is}, {compose_appl, As Is}, {compose_task, As Is}, {compose_thread, As Is}, {compose_node, As Is}, {compose_system, As Is}, {compose_workload, As Is}, {topcompose1, As Is}, {topcompose2, As Is} } }
-window_filter_module evt_type 1 53
+window_filter_module evt_type 1 54
 window_filter_module evt_type_label 1 "CPU: OpenMP Runtime/Label breakdown"
 

doc/user/emulation/events.md

@@ -1,7 +1,7 @@
 # Emulator events
 
 This is a exhaustive list of the events recognized by the emulator.
-Built on Nov 13 2024.
+Built on Feb  5 2025.
 
 ## Model nanos6
 
@@ -437,7 +437,7 @@ List of events for the model *ovni* with identifier **`O`** at version `1.1.0`:
 
 ## Model openmp
 
-List of events for the model *openmp* with identifier **`P`** at version `1.2.0`:
+List of events for the model *openmp* with identifier **`P`** at version `1.3.0`:
 <dl>
 <dt><a id="PBb" href="#PBb"><pre>PBb</pre></a></dt>
 <dd>begins plain barrier</dd>
@@ -575,6 +575,10 @@ List of events for the model *openmp* with identifier **`P`** at version `1.2.0`
 <dd>begins worksharing with type %{typeid}</dd>
 <dt><a id="PQe" href="#PQe"><pre>PQe(u32 typeid)</pre></a></dt>
 <dd>ends worksharing with type %{typeid}</dd>
+<dt><a id="Ppp" href="#Ppp"><pre>Ppp</pre></a></dt>
+<dd>sets progress state to Progressing</dd>
+<dt><a id="Pps" href="#Pps"><pre>Pps</pre></a></dt>
+<dd>sets progress state to Stalled</dd>
 </dl>
 
 ## Model tampi

doc/user/emulation/openmp.md

@@ -177,6 +177,19 @@ currently running on each thread. The ID is a monotonically increasing
 identifier assigned on task creation. Lower IDs correspond to tasks
 created at an earlier point than higher IDs.
 
+## Idle view
+
+The idle view shows the progress state of the running threads:
+*Progressing* and *Stalled*. The *Progressing* state is shown when they
+are making useful progress and the *Stalled* state when they are waiting
+for work. When workers start running, by definition, they begin in the
+Progressing state and there are some situations that make them
+transition to Stalled...
+
+!!! Note
+
+    TODO: Complete description
+
 ## Limitations
 
 As the compiler generates the code that perform the calls to the libompv

src/emu/emu_prv.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2021-2024 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2021-2025 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #ifndef EMU_PRV_H
@@ -35,7 +35,8 @@ enum emu_prv_types {
 	PRV_OPENMP_SUBSYSTEM = 50,
 	PRV_OPENMP_LABEL     = 51,
 	PRV_OPENMP_TASKID    = 52,
-	PRV_OPENMP_BREAKDOWN = 53,
+	PRV_OPENMP_IDLE      = 53,
+	PRV_OPENMP_BREAKDOWN = 54,
 	PRV_OVNI_MARK        = 100,
 	/* User marks [100, 200) */
 	PRV_RESERVED         = 200,

src/emu/openmp/event.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2023-2024 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2023-2025 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #include "openmp_priv.h"
@@ -14,7 +14,7 @@
 #include "thread.h"
 #include "value.h"
 
-enum { PUSH = 1, POP = 2, IGN = 3 };
+enum { PUSH = 1, POP, SET, IGN };
 
 static const int fn_table[256][256][3] = {
 	['B'] = {
@@ -95,6 +95,10 @@ static const int fn_table[256][256][3] = {
 		['f'] = { CH_SUBSYSTEM, PUSH, ST_RT_FORK_CALL },
 		['F'] = { CH_SUBSYSTEM, POP,  ST_RT_FORK_CALL },
 	},
+	['p'] = {
+		['p'] = { CH_IDLE, SET, ST_PROGRESSING },
+		['s'] = { CH_IDLE, SET, ST_STALLED },
+	},
 };
 
 static int
@@ -117,6 +121,8 @@ simple(struct emu *emu)
 		return chan_push(ch, value_int64(st));
 	} else if (action == POP) {
 		return chan_pop(ch, value_int64(st));
+	} else if (action == SET) {
+		return chan_set(ch, value_int64(st));
 	} else if (action == IGN) {
 		return 0; /* do nothing */
 	}
@@ -369,6 +375,7 @@ process_ev(struct emu *emu)
 		case 'M':
 		case 'H':
 		case 'C':
+		case 'p':
 			return simple(emu);
 		case 'P':
 			return pre_task(emu);

src/emu/openmp/openmp_priv.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2023-2024 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2023-2025 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #ifndef OPENMP_PRIV_H
@@ -16,6 +16,7 @@ enum openmp_chan {
 	CH_SUBSYSTEM = 0,
 	CH_LABEL,
 	CH_TASKID,
+	CH_IDLE,
 	CH_MAX,
 };
 
@@ -57,6 +58,14 @@ enum openmp_function_values {
 	ST_RT_WORKER_LOOP,
 };
 
+enum openmp_progress_values {
+	/* Can mix with subsystem values */
+	ST_PROGRESSING = 100,
+	ST_STALLED, /* Running thread doing nothing useful */
+	ST_IDLE,    /* No running threads */
+};
+
+
 struct openmp_thread {
 	struct model_thread m;
 	struct task_stack task_stack;

src/emu/openmp/setup.c

@@ -1,10 +1,11 @@
-/* Copyright (c) 2023-2024 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2023-2025 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #include "openmp_priv.h"
 #include <stddef.h>
 #include "chan.h"
 #include "common.h"
+#include "cpu.h"
 #include "emu.h"
 #include "emu_args.h"
 #include "emu_prv.h"
@@ -77,12 +78,15 @@ static struct ev_decl model_evlist[] = {
 	{ "PQx(u32 typeid)", "begins worksharing with type %{typeid}" },
 	{ "PQe(u32 typeid)", "ends worksharing with type %{typeid}" },
 
+	{ "Ppp", "sets progress state to Progressing" },
+	{ "Pps", "sets progress state to Stalled" },
+
 	{ NULL, NULL },
 };
 
 struct model_spec model_openmp = {
 	.name = model_name,
-	.version = "1.2.0",
+	.version = "1.3.0",
 	.evlist  = model_evlist,
 	.model = model_id,
 	.create  = model_openmp_create,
@@ -98,6 +102,7 @@ static const char *chan_name[CH_MAX] = {
 	[CH_SUBSYSTEM] = "subsystem",
 	[CH_LABEL]     = "label",
 	[CH_TASKID]    = "task ID",
+	[CH_IDLE]      = "idle",
 };
 
 static const int chan_stack[CH_MAX] = {
@@ -118,12 +123,14 @@ static const int pvt_type[CH_MAX] = {
 	[CH_SUBSYSTEM] = PRV_OPENMP_SUBSYSTEM,
 	[CH_LABEL]     = PRV_OPENMP_LABEL,
 	[CH_TASKID]    = PRV_OPENMP_TASKID,
+	[CH_IDLE]      = PRV_OPENMP_IDLE,
 };
 
 static const char *pcf_prefix[CH_MAX] = {
 	[CH_SUBSYSTEM] = "OpenMP subsystem",
 	[CH_LABEL]     = "OpenMP label",
 	[CH_TASKID]    = "OpenMP task ID",
+	[CH_IDLE]      = "OpenMP idle",
 };
 
 static const struct pcf_value_label openmp_subsystem_values[] = {
@@ -166,14 +173,23 @@ static const struct pcf_value_label openmp_subsystem_values[] = {
 	{ -1, NULL },
 };
 
+static const struct pcf_value_label openmp_progress_values[] = {
+	{ ST_PROGRESSING, "Progressing" },
+	{ ST_STALLED,     "Stalled" },
+	{ ST_IDLE,        "Idle" },
+	{ -1, NULL },
+};
+
 static const struct pcf_value_label *pcf_labels[CH_MAX] = {
 	[CH_SUBSYSTEM] = openmp_subsystem_values,
+	[CH_IDLE]      = openmp_progress_values,
 };
 
 static const long prv_flags[CH_MAX] = {
 	[CH_SUBSYSTEM] = PRV_SKIPDUPNULL,
 	[CH_LABEL]     = PRV_SKIPDUPNULL,
 	[CH_TASKID]    = PRV_SKIPDUPNULL,
+	[CH_IDLE]      = PRV_SKIPDUPNULL,
 };
 
 static const struct model_pvt_spec pvt_spec = {
@@ -189,12 +205,14 @@ static const int th_track[CH_MAX] = {
 	[CH_SUBSYSTEM] = TRACK_TH_ACT,
 	[CH_LABEL]     = TRACK_TH_ACT,
 	[CH_TASKID]    = TRACK_TH_ACT,
+	[CH_IDLE]      = TRACK_TH_ACT,
 };
 
 static const int cpu_track[CH_MAX] = {
 	[CH_SUBSYSTEM] = TRACK_TH_RUN,
 	[CH_LABEL]     = TRACK_TH_RUN,
 	[CH_TASKID]    = TRACK_TH_RUN,
+	[CH_IDLE]      = TRACK_TH_RUN,
 };
 
 /* ----------------- chan_spec ------------------ */
@@ -312,6 +330,23 @@ model_openmp_connect(struct emu *emu)
 		return -1;
 	}
 
+	for (struct thread *th = emu->system.threads; th; th = th->gnext) {
+		struct openmp_thread *mth = EXT(th, model_id);
+		struct chan *idle = &mth->m.ch[CH_IDLE];
+		/* By default set all threads as Progressing */
+		if (chan_set(idle, value_int64(ST_PROGRESSING)) != 0) {
+			err("chan_push idle failed");
+			return -1;
+		}
+	}
+
+	for (struct cpu *cpu = emu->system.cpus; cpu; cpu = cpu->next) {
+		struct openmp_cpu *mcpu = EXT(cpu, model_id);
+		struct mux *mux = &mcpu->m.track[CH_IDLE].mux;
+		/* Emit Idle when a CPU has no running threads */
+		mux_set_default(mux, value_int64(ST_IDLE));
+	}
+
 	return 0;
 }
 

test/emu/openmp/CMakeLists.txt

@@ -1,6 +1,7 @@
-# Copyright (c) 2024 Barcelona Supercomputing Center (BSC)
+# Copyright (c) 2024-2025 Barcelona Supercomputing Center (BSC)
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 test_emu(nested-ws.c)
 test_emu(nested-task.c)
 test_emu(mix-task-ws.c)
+test_emu(idle.c)

test/emu/openmp/idle.c

@@ -0,0 +1,34 @@
+/* Copyright (c) 2025 Barcelona Supercomputing Center (BSC)
+ * SPDX-License-Identifier: GPL-3.0-or-later */
+
+#include <stdlib.h>
+#include "compat.h"
+#include "instr.h"
+#include "instr_openmp.h"
+
+int
+main(void)
+{
+	instr_start(0, 1);
+	instr_openmp_init();
+
+	instr_openmp_type_create(1, "task");
+	instr_openmp_task_create(1, 1);
+
+	instr_openmp_stalled();
+	sleep_us(100);
+	instr_openmp_progressing();
+	sleep_us(100);
+	/* Pause the thread to create Idle state */
+	instr_thread_pause();
+	sleep_us(100);
+	instr_thread_resume();
+	sleep_us(100);
+	instr_openmp_task_execute(1);
+	sleep_us(100);
+	instr_openmp_task_end(1);
+
+	instr_end();
+
+	return 0;
+}

test/emu/openmp/instr_openmp.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2024 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2024-2025 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #ifndef INSTR_OPENMP_H
@@ -44,4 +44,7 @@ INSTR_1ARG(instr_openmp_task_end,     "PPe", uint32_t, taskid)
 INSTR_1ARG(instr_openmp_ws_enter, "PQx", uint32_t, typeid)
 INSTR_1ARG(instr_openmp_ws_exit,  "PQe", uint32_t, typeid)
 
+INSTR_0ARG(instr_openmp_progressing, "Ppp")
+INSTR_0ARG(instr_openmp_stalled,     "Pps")
+
 #endif /* INSTR_OPENMP_H */