perf sched: Introduce timehist command, again (v2)

index 662a0a6182e7..ccb602397b60 100644
@@ -137,7 +137,8 @@ int sample__fprintf_callchain(struct perf_sample *sample, int left_alignment,
 
 				if (print_symoffset) {
 					printed += __symbol__fprintf_symname_offs(node->sym, &node_al,
-										  print_unknown_as_addr, fp);
+										  print_unknown_as_addr,
+										  true, fp);
 				} else {
 					printed += __symbol__fprintf_symname(node->sym, &node_al,
 									     print_unknown_as_addr, fp);

@@ -188,7 +189,8 @@ int sample__fprintf_sym(struct perf_sample *sample, struct addr_location *al,
 			printed += fprintf(fp, " ");
 			if (print_symoffset) {
 				printed += __symbol__fprintf_symname_offs(al->sym, al,
-									  print_unknown_as_addr, fp);
+									  print_unknown_as_addr,
+									  true, fp);
 			} else {
 				printed += __symbol__fprintf_symname(al->sym, al,
 								     print_unknown_as_addr, fp);

index 2d0a905c879a..dec7e2d44885 100644
@@ -282,7 +282,8 @@ int symbol__annotation_init(void);
 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name);
 size_t __symbol__fprintf_symname_offs(const struct symbol *sym,
 				      const struct addr_location *al,
-				      bool unknown_as_addr, FILE *fp);
+				      bool unknown_as_addr,
+				      bool print_offsets, FILE *fp);
 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 				    const struct addr_location *al, FILE *fp);
 size_t __symbol__fprintf_symname(const struct symbol *sym,

index a680bdaa65dc..7c6b33e8e2d2 100644
@@ -15,14 +15,15 @@ size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 
 size_t __symbol__fprintf_symname_offs(const struct symbol *sym,
 				      const struct addr_location *al,
-				      bool unknown_as_addr, FILE *fp)
+				      bool unknown_as_addr,
+				      bool print_offsets, FILE *fp)
 {
 	unsigned long offset;
 	size_t length;
 
 	if (sym && sym->name) {
 		length = fprintf(fp, "%s", sym->name);
-		if (al) {
+		if (al && print_offsets) {
 			if (al->addr < sym->end)
 				offset = al->addr - sym->start;
 			else

@@ -40,19 +41,19 @@ size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 				    const struct addr_location *al,
 				    FILE *fp)
 {
-	return __symbol__fprintf_symname_offs(sym, al, false, fp);
+	return __symbol__fprintf_symname_offs(sym, al, false, true, fp);
 }
 
 size_t __symbol__fprintf_symname(const struct symbol *sym,
 				 const struct addr_location *al,
 				 bool unknown_as_addr, FILE *fp)
 {
-	return __symbol__fprintf_symname_offs(sym, al, unknown_as_addr, fp);
+	return __symbol__fprintf_symname_offs(sym, al, unknown_as_addr, false, fp);
 }
 
 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 {
-	return __symbol__fprintf_symname_offs(sym, NULL, false, fp);
+	return __symbol__fprintf_symname_offs(sym, NULL, false, false, fp);
 }
 
 size_t dso__fprintf_symbols_by_name(struct dso *dso,

index 8cd7cd227483..27fa3a343577 100644
@@ -391,6 +391,7 @@ int perf_evsel__fprintf(struct perf_evsel *evsel,
 #define EVSEL__PRINT_ONELINE		(1<<4)
 #define EVSEL__PRINT_SRCLINE		(1<<5)
 #define EVSEL__PRINT_UNKNOWN_AS_ADDR	(1<<6)
+#define EVSEL__PRINT_CALLCHAIN_ARROW	(1<<7)
 
 struct callchain_cursor;
 

index ccb602397b60..53bb614feafb 100644
@@ -108,7 +108,9 @@ int sample__fprintf_callchain(struct perf_sample *sample, int left_alignment,
 	int print_oneline = print_opts & EVSEL__PRINT_ONELINE;
 	int print_srcline = print_opts & EVSEL__PRINT_SRCLINE;
 	int print_unknown_as_addr = print_opts & EVSEL__PRINT_UNKNOWN_AS_ADDR;
+	int print_arrow = print_opts & EVSEL__PRINT_CALLCHAIN_ARROW;
 	char s = print_oneline ? ' ' : '\t';
+	bool first = true;
 
 	if (sample->callchain) {
 		struct addr_location node_al;

@@ -124,6 +126,9 @@ int sample__fprintf_callchain(struct perf_sample *sample, int left_alignment,
 
 			printed += fprintf(fp, "%-*.*s", left_alignment, left_alignment, " ");
 
+			if (print_arrow && !first)
+				printed += fprintf(fp, " <-");
+
 			if (print_ip)
 				printed += fprintf(fp, "%c%16" PRIx64, s, node->ip);
 

@@ -158,6 +163,7 @@ int sample__fprintf_callchain(struct perf_sample *sample, int left_alignment,
 				printed += fprintf(fp, "\n");
 
 			callchain_cursor_advance(cursor);
+			first = false;
 		}
 	}
 

index fb3441211e4b..c0ac0c9557e8 100644
@@ -13,12 +13,14 @@
 #include "util/cloexec.h"
 #include "util/thread_map.h"
 #include "util/color.h"
+#include "util/stat.h"
 
 #include <subcmd/parse-options.h>
 #include "util/trace-event.h"
 
 #include "util/debug.h"
 
+#include <linux/log2.h>
 #include <sys/prctl.h>
 #include <sys/resource.h>
 

@@ -194,6 +196,29 @@ struct perf_sched {
 	struct perf_sched_map map;
 };
 
+/* per thread run time data */
+struct thread_runtime {
+	u64 last_time;      /* time of previous sched in/out event */
+	u64 dt_run;         /* run time */
+	u64 dt_wait;        /* time between CPU access (off cpu) */
+	u64 dt_delay;       /* time between wakeup and sched-in */
+	u64 ready_to_run;   /* time of wakeup */
+
+	struct stats run_stats;
+	u64 total_run_time;
+};
+
+/* per event run time data */
+struct evsel_runtime {
+	u64 *last_time; /* time this event was last seen per cpu */
+	u32 ncpu;       /* highest cpu slot allocated */
+};
+
+/* track idle times per cpu */
+static struct thread **idle_threads;
+static int idle_max_cpu;
+static char idle_comm[] = "<idle>";
+
 static u64 get_nsecs(void)
 {
 	struct timespec ts;

@@ -1654,6 +1679,546 @@ static int perf_sched__read_events(struct perf_sched *sched)
 	return rc;
 }
 
+/*
+ * scheduling times are printed as msec.usec
+ */
+static inline void print_sched_time(unsigned long long nsecs, int width)
+{
+	unsigned long msecs;
+	unsigned long usecs;
+
+	msecs  = nsecs / NSEC_PER_MSEC;
+	nsecs -= msecs * NSEC_PER_MSEC;
+	usecs  = nsecs / NSEC_PER_USEC;
+	printf("%*lu.%03lu ", width, msecs, usecs);
+}
+
+/*
+ * returns runtime data for event, allocating memory for it the
+ * first time it is used.
+ */
+static struct evsel_runtime *perf_evsel__get_runtime(struct perf_evsel *evsel)
+{
+	struct evsel_runtime *r = evsel->priv;
+
+	if (r == NULL) {
+		r = zalloc(sizeof(struct evsel_runtime));
+		evsel->priv = r;
+	}
+
+	return r;
+}
+
+/*
+ * save last time event was seen per cpu
+ */
+static void perf_evsel__save_time(struct perf_evsel *evsel,
+				  u64 timestamp, u32 cpu)
+{
+	struct evsel_runtime *r = perf_evsel__get_runtime(evsel);
+
+	if (r == NULL)
+		return;
+
+	if ((cpu >= r->ncpu) || (r->last_time == NULL)) {
+		int i, n = __roundup_pow_of_two(cpu+1);
+		void *p = r->last_time;
+
+		p = realloc(r->last_time, n * sizeof(u64));
+		if (!p)
+			return;
+
+		r->last_time = p;
+		for (i = r->ncpu; i < n; ++i)
+			r->last_time[i] = (u64) 0;
+
+		r->ncpu = n;
+	}
+
+	r->last_time[cpu] = timestamp;
+}
+
+/* returns last time this event was seen on the given cpu */
+static u64 perf_evsel__get_time(struct perf_evsel *evsel, u32 cpu)
+{
+	struct evsel_runtime *r = perf_evsel__get_runtime(evsel);
+
+	if ((r == NULL) || (r->last_time == NULL) || (cpu >= r->ncpu))
+		return 0;
+
+	return r->last_time[cpu];
+}
+
+static int comm_width = 20;
+
+static char *timehist_get_commstr(struct thread *thread)
+{
+	static char str[32];
+	const char *comm = thread__comm_str(thread);
+	pid_t tid = thread->tid;
+	pid_t pid = thread->pid_;
+	int n;
+
+	if (pid == 0)
+		n = scnprintf(str, sizeof(str), "%s", comm);
+
+	else if (tid != pid)
+		n = scnprintf(str, sizeof(str), "%s[%d/%d]", comm, tid, pid);
+
+	else
+		n = scnprintf(str, sizeof(str), "%s[%d]", comm, tid);
+
+	if (n > comm_width)
+		comm_width = n;
+
+	return str;
+}
+
+static void timehist_header(void)
+{
+	printf("%15s %6s ", "time", "cpu");
+
+	printf(" %-20s  %9s  %9s  %9s",
+		"task name", "wait time", "sch delay", "run time");
+
+	printf("\n");
+
+	/*
+	 * units row
+	 */
+	printf("%15s %-6s ", "", "");
+
+	printf(" %-20s  %9s  %9s  %9s\n", "[tid/pid]", "(msec)", "(msec)", "(msec)");
+
+	/*
+	 * separator
+	 */
+	printf("%.15s %.6s ", graph_dotted_line, graph_dotted_line);
+
+	printf(" %.20s  %.9s  %.9s  %.9s",
+		graph_dotted_line, graph_dotted_line, graph_dotted_line,
+		graph_dotted_line);
+
+	printf("\n");
+}
+
+static void timehist_print_sample(struct perf_sample *sample,
+				  struct thread *thread)
+{
+	struct thread_runtime *tr = thread__priv(thread);
+	char tstr[64];
+
+	timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
+	printf("%15s [%04d] ", tstr, sample->cpu);
+
+	printf(" %-*s ", comm_width, timehist_get_commstr(thread));
+
+	print_sched_time(tr->dt_wait, 6);
+	print_sched_time(tr->dt_delay, 6);
+	print_sched_time(tr->dt_run, 6);
+	printf("\n");
+}
+
+/*
+ * Explanation of delta-time stats:
+ *
+ *            t = time of current schedule out event
+ *        tprev = time of previous sched out event
+ *                also time of schedule-in event for current task
+ *    last_time = time of last sched change event for current task
+ *                (i.e, time process was last scheduled out)
+ * ready_to_run = time of wakeup for current task
+ *
+ * -----|------------|------------|------------|------
+ *    last         ready        tprev          t
+ *    time         to run
+ *
+ *      |-------- dt_wait --------|
+ *                   |- dt_delay -|-- dt_run --|
+ *
+ *   dt_run = run time of current task
+ *  dt_wait = time between last schedule out event for task and tprev
+ *            represents time spent off the cpu
+ * dt_delay = time between wakeup and schedule-in of task
+ */
+
+static void timehist_update_runtime_stats(struct thread_runtime *r,
+					 u64 t, u64 tprev)
+{
+	r->dt_delay   = 0;
+	r->dt_wait    = 0;
+	r->dt_run     = 0;
+	if (tprev) {
+		r->dt_run = t - tprev;
+		if (r->ready_to_run) {
+			if (r->ready_to_run > tprev)
+				pr_debug("time travel: wakeup time for task > previous sched_switch event\n");
+			else
+				r->dt_delay = tprev - r->ready_to_run;
+		}
+
+		if (r->last_time > tprev)
+			pr_debug("time travel: last sched out time for task > previous sched_switch event\n");
+		else if (r->last_time)
+			r->dt_wait = tprev - r->last_time;
+	}
+
+	update_stats(&r->run_stats, r->dt_run);
+	r->total_run_time += r->dt_run;
+}
+
+static bool is_idle_sample(struct perf_sample *sample,
+			   struct perf_evsel *evsel)
+{
+	/* pid 0 == swapper == idle task */
+	if (sample->pid == 0)
+		return true;
+
+	if (strcmp(perf_evsel__name(evsel), "sched:sched_switch") == 0) {
+		if (perf_evsel__intval(evsel, sample, "prev_pid") == 0)
+			return true;
+	}
+	return false;
+}
+
+/*
+ * Track idle stats per cpu by maintaining a local thread
+ * struct for the idle task on each cpu.
+ */
+static int init_idle_threads(int ncpu)
+{
+	int i;
+
+	idle_threads = zalloc(ncpu * sizeof(struct thread *));
+	if (!idle_threads)
+		return -ENOMEM;
+
+	idle_max_cpu = ncpu - 1;
+
+	/* allocate the actual thread struct if needed */
+	for (i = 0; i < ncpu; ++i) {
+		idle_threads[i] = thread__new(0, 0);
+		if (idle_threads[i] == NULL)
+			return -ENOMEM;
+
+		thread__set_comm(idle_threads[i], idle_comm, 0);
+	}
+
+	return 0;
+}
+
+static void free_idle_threads(void)
+{
+	int i;
+
+	if (idle_threads == NULL)
+		return;
+
+	for (i = 0; i <= idle_max_cpu; ++i) {
+		if ((idle_threads[i]))
+			thread__delete(idle_threads[i]);
+	}
+
+	free(idle_threads);
+}
+
+static struct thread *get_idle_thread(int cpu)
+{
+	/*
+	 * expand/allocate array of pointers to local thread
+	 * structs if needed
+	 */
+	if ((cpu >= idle_max_cpu) || (idle_threads == NULL)) {
+		int i, j = __roundup_pow_of_two(cpu+1);
+		void *p;
+
+		p = realloc(idle_threads, j * sizeof(struct thread *));
+		if (!p)
+			return NULL;
+
+		idle_threads = (struct thread **) p;
+		i = idle_max_cpu ? idle_max_cpu + 1 : 0;
+		for (; i < j; ++i)
+			idle_threads[i] = NULL;
+
+		idle_max_cpu = j;
+	}
+
+	/* allocate a new thread struct if needed */
+	if (idle_threads[cpu] == NULL) {
+		idle_threads[cpu] = thread__new(0, 0);
+
+		if (idle_threads[cpu]) {
+			idle_threads[cpu]->tid = 0;
+			thread__set_comm(idle_threads[cpu], idle_comm, 0);
+		}
+	}
+
+	return idle_threads[cpu];
+}
+
+/*
+ * handle runtime stats saved per thread
+ */
+static struct thread_runtime *thread__init_runtime(struct thread *thread)
+{
+	struct thread_runtime *r;
+
+	r = zalloc(sizeof(struct thread_runtime));
+	if (!r)
+		return NULL;
+
+	init_stats(&r->run_stats);
+	thread__set_priv(thread, r);
+
+	return r;
+}
+
+static struct thread_runtime *thread__get_runtime(struct thread *thread)
+{
+	struct thread_runtime *tr;
+
+	tr = thread__priv(thread);
+	if (tr == NULL) {
+		tr = thread__init_runtime(thread);
+		if (tr == NULL)
+			pr_debug("Failed to malloc memory for runtime data.\n");
+	}
+
+	return tr;
+}
+
+static struct thread *timehist_get_thread(struct perf_sample *sample,
+					  struct machine *machine,
+					  struct perf_evsel *evsel)
+{
+	struct thread *thread;
+
+	if (is_idle_sample(sample, evsel)) {
+		thread = get_idle_thread(sample->cpu);
+		if (thread == NULL)
+			pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);
+
+	} else {
+		thread = machine__findnew_thread(machine, sample->pid, sample->tid);
+		if (thread == NULL) {
+			pr_debug("Failed to get thread for tid %d. skipping sample.\n",
+				 sample->tid);
+		}
+	}
+
+	return thread;
+}
+
+static bool timehist_skip_sample(struct thread *thread)
+{
+	bool rc = false;
+
+	if (thread__is_filtered(thread))
+		rc = true;
+
+	return rc;
+}
+
+static int timehist_sched_wakeup_event(struct perf_tool *tool __maybe_unused,
+				       union perf_event *event __maybe_unused,
+				       struct perf_evsel *evsel,
+				       struct perf_sample *sample,
+				       struct machine *machine)
+{
+	struct thread *thread;
+	struct thread_runtime *tr = NULL;
+	/* want pid of awakened task not pid in sample */
+	const u32 pid = perf_evsel__intval(evsel, sample, "pid");
+
+	thread = machine__findnew_thread(machine, 0, pid);
+	if (thread == NULL)
+		return -1;
+
+	tr = thread__get_runtime(thread);
+	if (tr == NULL)
+		return -1;
+
+	if (tr->ready_to_run == 0)
+		tr->ready_to_run = sample->time;
+
+	return 0;
+}
+
+static int timehist_sched_change_event(struct perf_tool *tool __maybe_unused,
+				       union perf_event *event,
+				       struct perf_evsel *evsel,
+				       struct perf_sample *sample,
+				       struct machine *machine)
+{
+	struct addr_location al;
+	struct thread *thread;
+	struct thread_runtime *tr = NULL;
+	u64 tprev;
+	int rc = 0;
+
+	if (machine__resolve(machine, &al, sample) < 0) {
+		pr_err("problem processing %d event. skipping it\n",
+		       event->header.type);
+		rc = -1;
+		goto out;
+	}
+
+	thread = timehist_get_thread(sample, machine, evsel);
+	if (thread == NULL) {
+		rc = -1;
+		goto out;
+	}
+
+	if (timehist_skip_sample(thread))
+		goto out;
+
+	tr = thread__get_runtime(thread);
+	if (tr == NULL) {
+		rc = -1;
+		goto out;
+	}
+
+	tprev = perf_evsel__get_time(evsel, sample->cpu);
+
+	timehist_update_runtime_stats(tr, sample->time, tprev);
+	timehist_print_sample(sample, thread);
+
+out:
+	if (tr) {
+		/* time of this sched_switch event becomes last time task seen */
+		tr->last_time = sample->time;
+
+		/* sched out event for task so reset ready to run time */
+		tr->ready_to_run = 0;
+	}
+
+	perf_evsel__save_time(evsel, sample->time, sample->cpu);
+
+	return rc;
+}
+
+static int timehist_sched_switch_event(struct perf_tool *tool,
+			     union perf_event *event,
+			     struct perf_evsel *evsel,
+			     struct perf_sample *sample,
+			     struct machine *machine __maybe_unused)
+{
+	return timehist_sched_change_event(tool, event, evsel, sample, machine);
+}
+
+static int process_lost(struct perf_tool *tool __maybe_unused,
+			union perf_event *event,
+			struct perf_sample *sample,
+			struct machine *machine __maybe_unused)
+{
+	char tstr[64];
+
+	timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
+	printf("%15s ", tstr);
+	printf("lost %" PRIu64 " events on cpu %d\n", event->lost.lost, sample->cpu);
+
+	return 0;
+}
+
+
+typedef int (*sched_handler)(struct perf_tool *tool,
+			  union perf_event *event,
+			  struct perf_evsel *evsel,
+			  struct perf_sample *sample,
+			  struct machine *machine);
+
+static int perf_timehist__process_sample(struct perf_tool *tool,
+					 union perf_event *event,
+					 struct perf_sample *sample,
+					 struct perf_evsel *evsel,
+					 struct machine *machine)
+{
+	struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
+	int err = 0;
+	int this_cpu = sample->cpu;
+
+	if (this_cpu > sched->max_cpu)
+		sched->max_cpu = this_cpu;
+
+	if (evsel->handler != NULL) {
+		sched_handler f = evsel->handler;
+
+		err = f(tool, event, evsel, sample, machine);
+	}
+
+	return err;
+}
+
+static int perf_sched__timehist(struct perf_sched *sched)
+{
+	const struct perf_evsel_str_handler handlers[] = {
+		{ "sched:sched_switch",       timehist_sched_switch_event, },
+		{ "sched:sched_wakeup",	      timehist_sched_wakeup_event, },
+		{ "sched:sched_wakeup_new",   timehist_sched_wakeup_event, },
+	};
+	struct perf_data_file file = {
+		.path = input_name,
+		.mode = PERF_DATA_MODE_READ,
+	};
+
+	struct perf_session *session;
+	int err = -1;
+
+	/*
+	 * event handlers for timehist option
+	 */
+	sched->tool.sample	 = perf_timehist__process_sample;
+	sched->tool.mmap	 = perf_event__process_mmap;
+	sched->tool.comm	 = perf_event__process_comm;
+	sched->tool.exit	 = perf_event__process_exit;
+	sched->tool.fork	 = perf_event__process_fork;
+	sched->tool.lost	 = process_lost;
+	sched->tool.attr	 = perf_event__process_attr;
+	sched->tool.tracing_data = perf_event__process_tracing_data;
+	sched->tool.build_id	 = perf_event__process_build_id;
+
+	sched->tool.ordered_events = true;
+	sched->tool.ordering_requires_timestamps = true;
+
+	session = perf_session__new(&file, false, &sched->tool);
+	if (session == NULL)
+		return -ENOMEM;
+
+	symbol__init(&session->header.env);
+
+	setup_pager();
+
+	/* setup per-evsel handlers */
+	if (perf_session__set_tracepoints_handlers(session, handlers))
+		goto out;
+
+	if (!perf_session__has_traces(session, "record -R"))
+		goto out;
+
+	/* pre-allocate struct for per-CPU idle stats */
+	sched->max_cpu = session->header.env.nr_cpus_online;
+	if (sched->max_cpu == 0)
+		sched->max_cpu = 4;
+	if (init_idle_threads(sched->max_cpu))
+		goto out;
+
+	timehist_header();
+
+	err = perf_session__process_events(session);
+	if (err) {
+		pr_err("Failed to process events, error %d", err);
+		goto out;
+	}
+
+out:
+	free_idle_threads();
+	perf_session__delete(session);
+
+	return err;
+}
+
+
 static void print_bad_events(struct perf_sched *sched)
 {
 	if (sched->nr_unordered_timestamps && sched->nr_timestamps) {

@@ -1970,8 +2535,6 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 	const struct option latency_options[] = {
 	OPT_STRING('s', "sort", &sched.sort_order, "key[,key2...]",
 		   "sort by key(s): runtime, switch, avg, max"),
-	OPT_INCR('v', "verbose", &verbose,
-		    "be more verbose (show symbol address, etc)"),
 	OPT_INTEGER('C', "CPU", &sched.profile_cpu,
 		    "CPU to profile on"),
 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,

@@ -1983,8 +2546,6 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 	const struct option replay_options[] = {
 	OPT_UINTEGER('r', "repeat", &sched.replay_repeat,
 		     "repeat the workload replay N times (-1: infinite)"),
-	OPT_INCR('v', "verbose", &verbose,
-		    "be more verbose (show symbol address, etc)"),
 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 		    "dump raw trace in ASCII"),
 	OPT_BOOLEAN('f', "force", &sched.force, "don't complain, do it"),

@@ -2001,6 +2562,16 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
                     "display given CPUs in map"),
 	OPT_PARENT(sched_options)
 	};
+	const struct option timehist_options[] = {
+	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
+		   "file", "vmlinux pathname"),
+	OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
+		   "file", "kallsyms pathname"),
+	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
+		    "Look for files with symbols relative to this directory"),
+	OPT_PARENT(sched_options)
+	};
+
 	const char * const latency_usage[] = {
 		"perf sched latency [<options>]",
 		NULL

@@ -2013,8 +2584,13 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 		"perf sched map [<options>]",
 		NULL
 	};
+	const char * const timehist_usage[] = {
+		"perf sched timehist [<options>]",
+		NULL
+	};
 	const char *const sched_subcommands[] = { "record", "latency", "map",
-						  "replay", "script", NULL };
+						  "replay", "script",
+						  "timehist", NULL };
 	const char *sched_usage[] = {
 		NULL,
 		NULL

@@ -2077,6 +2653,14 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 				usage_with_options(replay_usage, replay_options);
 		}
 		return perf_sched__replay(&sched);
+	} else if (!strcmp(argv[0], "timehist")) {
+		if (argc) {
+			argc = parse_options(argc, argv, timehist_options,
+					     timehist_usage, 0);
+			if (argc)
+				usage_with_options(timehist_usage, timehist_options);
+		}
+		return perf_sched__timehist(&sched);
 	} else {
 		usage_with_options(sched_usage, sched_options);
 	}

index c0ac0c9557e8..1e7d81ad5ec6 100644
@@ -194,6 +194,11 @@ struct perf_sched {
 	bool force;
 	bool skip_merge;
 	struct perf_sched_map map;
+
+	/* options for timehist command */
+	bool		summary;
+	bool		summary_only;
+	u64		skipped_samples;
 };
 
 /* per thread run time data */

@@ -2010,12 +2015,15 @@ static struct thread *timehist_get_thread(struct perf_sample *sample,
 	return thread;
 }
 
-static bool timehist_skip_sample(struct thread *thread)
+static bool timehist_skip_sample(struct perf_sched *sched,
+				 struct thread *thread)
 {
 	bool rc = false;
 
-	if (thread__is_filtered(thread))
+	if (thread__is_filtered(thread)) {
 		rc = true;
+		sched->skipped_samples++;
+	}
 
 	return rc;
 }

@@ -2045,7 +2053,7 @@ static int timehist_sched_wakeup_event(struct perf_tool *tool __maybe_unused,
 	return 0;
 }
 
-static int timehist_sched_change_event(struct perf_tool *tool __maybe_unused,
+static int timehist_sched_change_event(struct perf_tool *tool,
 				       union perf_event *event,
 				       struct perf_evsel *evsel,
 				       struct perf_sample *sample,

@@ -2056,6 +2064,7 @@ static int timehist_sched_change_event(struct perf_tool *tool __maybe_unused,
 	struct thread_runtime *tr = NULL;
 	u64 tprev;
 	int rc = 0;
+	struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
 
 	if (machine__resolve(machine, &al, sample) < 0) {
 		pr_err("problem processing %d event. skipping it\n",

@@ -2070,7 +2079,7 @@ static int timehist_sched_change_event(struct perf_tool *tool __maybe_unused,
 		goto out;
 	}
 
-	if (timehist_skip_sample(thread))
+	if (timehist_skip_sample(sched, thread))
 		goto out;
 
 	tr = thread__get_runtime(thread);

@@ -2082,7 +2091,8 @@ static int timehist_sched_change_event(struct perf_tool *tool __maybe_unused,
 	tprev = perf_evsel__get_time(evsel, sample->cpu);
 
 	timehist_update_runtime_stats(tr, sample->time, tprev);
-	timehist_print_sample(sample, thread);
+	if (!sched->summary_only)
+		timehist_print_sample(sample, thread);
 
 out:
 	if (tr) {

@@ -2122,6 +2132,131 @@ static int process_lost(struct perf_tool *tool __maybe_unused,
 }
 
 
+static void print_thread_runtime(struct thread *t,
+				 struct thread_runtime *r)
+{
+	double mean = avg_stats(&r->run_stats);
+	float stddev;
+
+	printf("%*s   %5d  %9" PRIu64 " ",
+	       comm_width, timehist_get_commstr(t), t->ppid,
+	       (u64) r->run_stats.n);
+
+	print_sched_time(r->total_run_time, 8);
+	stddev = rel_stddev_stats(stddev_stats(&r->run_stats), mean);
+	print_sched_time(r->run_stats.min, 6);
+	printf(" ");
+	print_sched_time((u64) mean, 6);
+	printf(" ");
+	print_sched_time(r->run_stats.max, 6);
+	printf("  ");
+	printf("%5.2f", stddev);
+	printf("\n");
+}
+
+struct total_run_stats {
+	u64  sched_count;
+	u64  task_count;
+	u64  total_run_time;
+};
+
+static int __show_thread_runtime(struct thread *t, void *priv)
+{
+	struct total_run_stats *stats = priv;
+	struct thread_runtime *r;
+
+	if (thread__is_filtered(t))
+		return 0;
+
+	r = thread__priv(t);
+	if (r && r->run_stats.n) {
+		stats->task_count++;
+		stats->sched_count += r->run_stats.n;
+		stats->total_run_time += r->total_run_time;
+		print_thread_runtime(t, r);
+	}
+
+	return 0;
+}
+
+static int show_thread_runtime(struct thread *t, void *priv)
+{
+	if (t->dead)
+		return 0;
+
+	return __show_thread_runtime(t, priv);
+}
+
+static int show_deadthread_runtime(struct thread *t, void *priv)
+{
+	if (!t->dead)
+		return 0;
+
+	return __show_thread_runtime(t, priv);
+}
+
+static void timehist_print_summary(struct perf_sched *sched,
+				   struct perf_session *session)
+{
+	struct machine *m = &session->machines.host;
+	struct total_run_stats totals;
+	u64 task_count;
+	struct thread *t;
+	struct thread_runtime *r;
+	int i;
+
+	memset(&totals, 0, sizeof(totals));
+
+	if (comm_width < 30)
+		comm_width = 30;
+
+	printf("\nRuntime summary\n");
+	printf("%*s  parent   sched-in  ", comm_width, "comm");
+	printf("   run-time    min-run     avg-run     max-run  stddev\n");
+	printf("%*s            (count)  ", comm_width, "");
+	printf("     (msec)     (msec)      (msec)      (msec)       %%\n");
+	printf("%.105s\n", graph_dotted_line);
+
+	machine__for_each_thread(m, show_thread_runtime, &totals);
+	task_count = totals.task_count;
+	if (!task_count)
+		printf("<no still running tasks>\n");
+
+	printf("\nTerminated tasks:\n");
+	machine__for_each_thread(m, show_deadthread_runtime, &totals);
+	if (task_count == totals.task_count)
+		printf("<no terminated tasks>\n");
+
+	/* CPU idle stats not tracked when samples were skipped */
+	if (sched->skipped_samples)
+		return;
+
+	printf("\nIdle stats:\n");
+	for (i = 0; i <= idle_max_cpu; ++i) {
+		t = idle_threads[i];
+		if (!t)
+			continue;
+
+		r = thread__priv(t);
+		if (r && r->run_stats.n) {
+			totals.sched_count += r->run_stats.n;
+			printf("    CPU %2d idle for ", i);
+			print_sched_time(r->total_run_time, 6);
+			printf(" msec\n");
+		} else
+			printf("    CPU %2d idle entire time window\n", i);
+	}
+
+	printf("\n"
+	       "    Total number of unique tasks: %" PRIu64 "\n"
+	       "Total number of context switches: %" PRIu64 "\n"
+	       "           Total run time (msec): ",
+	       totals.task_count, totals.sched_count);
+
+	print_sched_time(totals.total_run_time, 2);
+	printf("\n");
+}
+
 typedef int (*sched_handler)(struct perf_tool *tool,
 			  union perf_event *event,
 			  struct perf_evsel *evsel,

@@ -2163,6 +2298,7 @@ static int perf_sched__timehist(struct perf_sched *sched)
 	};
 
 	struct perf_session *session;
+	struct perf_evlist *evlist;
 	int err = -1;
 
 	/*

@@ -2185,6 +2321,8 @@ static int perf_sched__timehist(struct perf_sched *sched)
 	if (session == NULL)
 		return -ENOMEM;
 
+	evlist = session->evlist;
+
 	symbol__init(&session->header.env);
 
 	setup_pager();

@@ -2203,7 +2341,12 @@ static int perf_sched__timehist(struct perf_sched *sched)
 	if (init_idle_threads(sched->max_cpu))
 		goto out;
 
-	timehist_header();
+	/* summary_only implies summary option, but don't overwrite summary if set */
+	if (sched->summary_only)
+		sched->summary = sched->summary_only;
+
+	if (!sched->summary_only)
+		timehist_header();
 
 	err = perf_session__process_events(session);
 	if (err) {

@@ -2211,6 +2354,13 @@ static int perf_sched__timehist(struct perf_sched *sched)
 		goto out;
 	}
 
+	sched->nr_events      = evlist->stats.nr_events[0];
+	sched->nr_lost_events = evlist->stats.total_lost;
+	sched->nr_lost_chunks = evlist->stats.nr_events[PERF_RECORD_LOST];
+
+	if (sched->summary)
+		timehist_print_summary(sched, session);
+
 out:
 	free_idle_threads();
 	perf_session__delete(session);

@@ -2569,6 +2719,10 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 		   "file", "kallsyms pathname"),
 	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 		    "Look for files with symbols relative to this directory"),
+	OPT_BOOLEAN('s', "summary", &sched.summary_only,
+		    "Show only syscall summary with statistics"),
+	OPT_BOOLEAN('S', "with-summary", &sched.summary,
+		    "Show all syscalls and summary with statistics"),
 	OPT_PARENT(sched_options)
 	};
 

index 1e7d81ad5ec6..8fb7bcc2cb76 100644
@@ -198,6 +198,7 @@ struct perf_sched {
 	/* options for timehist command */
 	bool		summary;
 	bool		summary_only;
+	bool		show_wakeups;
 	u64		skipped_samples;
 };
 

@@ -1807,7 +1808,8 @@ static void timehist_header(void)
 	printf("\n");
 }
 
-static void timehist_print_sample(struct perf_sample *sample,
+static void timehist_print_sample(struct perf_sched *sched,
+				  struct perf_sample *sample,
 				  struct thread *thread)
 {
 	struct thread_runtime *tr = thread__priv(thread);

@@ -1821,6 +1823,10 @@ static void timehist_print_sample(struct perf_sample *sample,
 	print_sched_time(tr->dt_wait, 6);
 	print_sched_time(tr->dt_delay, 6);
 	print_sched_time(tr->dt_run, 6);
+
+	if (sched->show_wakeups)
+		printf("  %-*s", comm_width, "");
+
 	printf("\n");
 }
 

@@ -2028,12 +2034,44 @@ static bool timehist_skip_sample(struct perf_sched *sched,
 	return rc;
 }
 
-static int timehist_sched_wakeup_event(struct perf_tool *tool __maybe_unused,
+static void timehist_print_wakeup_event(struct perf_sched *sched,
+					struct perf_sample *sample,
+					struct machine *machine,
+					struct thread *awakened)
+{
+	struct thread *thread;
+	char tstr[64];
+
+	thread = machine__findnew_thread(machine, sample->pid, sample->tid);
+	if (thread == NULL)
+		return;
+
+	/* show wakeup unless both awakee and awaker are filtered */
+	if (timehist_skip_sample(sched, thread) &&
+	    timehist_skip_sample(sched, awakened)) {
+		return;
+	}
+
+	timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
+	printf("%15s [%04d] ", tstr, sample->cpu);
+
+	printf(" %-*s ", comm_width, timehist_get_commstr(thread));
+
+	/* dt spacer */
+	printf("  %9s  %9s  %9s ", "", "", "");
+
+	printf("awakened: %s", timehist_get_commstr(awakened));
+
+	printf("\n");
+}
+
+static int timehist_sched_wakeup_event(struct perf_tool *tool,
 				       union perf_event *event __maybe_unused,
 				       struct perf_evsel *evsel,
 				       struct perf_sample *sample,
 				       struct machine *machine)
 {
+	struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
 	struct thread *thread;
 	struct thread_runtime *tr = NULL;
 	/* want pid of awakened task not pid in sample */

@@ -2050,6 +2088,10 @@ static int timehist_sched_wakeup_event(struct perf_tool *tool __maybe_unused,
 	if (tr->ready_to_run == 0)
 		tr->ready_to_run = sample->time;
 
+	/* show wakeups if requested */
+	if (sched->show_wakeups)
+		timehist_print_wakeup_event(sched, sample, machine, thread);
+
 	return 0;
 }
 

@@ -2059,12 +2101,12 @@ static int timehist_sched_change_event(struct perf_tool *tool,
 				       struct perf_sample *sample,
 				       struct machine *machine)
 {
+	struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
 	struct addr_location al;
 	struct thread *thread;
 	struct thread_runtime *tr = NULL;
 	u64 tprev;
 	int rc = 0;
-	struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
 
 	if (machine__resolve(machine, &al, sample) < 0) {
 		pr_err("problem processing %d event. skipping it\n",

@@ -2092,7 +2134,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
 
 	timehist_update_runtime_stats(tr, sample->time, tprev);
 	if (!sched->summary_only)
-		timehist_print_sample(sample, thread);
+		timehist_print_sample(sched, sample, thread);
 
 out:
 	if (tr) {

@@ -2723,6 +2765,7 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 		    "Show only syscall summary with statistics"),
 	OPT_BOOLEAN('S', "with-summary", &sched.summary,
 		    "Show all syscalls and summary with statistics"),
+	OPT_BOOLEAN('w', "wakeups", &sched.show_wakeups, "Show wakeup events"),
 	OPT_PARENT(sched_options)
 	};
 

@@ -2814,6 +2857,13 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 			if (argc)
 				usage_with_options(timehist_usage, timehist_options);
 		}
+		if (sched.show_wakeups && sched.summary_only) {
+			pr_err(" Error: -s and -w are mutually exclusive.\n");
+			parse_options_usage(timehist_usage, timehist_options, "s", true);
+			parse_options_usage(NULL, timehist_options, "w", true);
+			return -EINVAL;
+		}
+
 		return perf_sched__timehist(&sched);
 	} else {
 		usage_with_options(sched_usage, sched_options);

index 8fb7bcc2cb76..1f8731640809 100644
@@ -14,6 +14,7 @@
 #include "util/thread_map.h"
 #include "util/color.h"
 #include "util/stat.h"
+#include "util/callchain.h"
 
 #include <subcmd/parse-options.h>
 #include "util/trace-event.h"

@@ -198,6 +199,8 @@ struct perf_sched {
 	/* options for timehist command */
 	bool		summary;
 	bool		summary_only;
+	bool		show_callchain;
+	unsigned int	max_stack;
 	bool		show_wakeups;
 	u64		skipped_samples;
 };

@@ -1810,6 +1813,7 @@ static void timehist_header(void)
 
 static void timehist_print_sample(struct perf_sched *sched,
 				  struct perf_sample *sample,
+				  struct addr_location *al,
 				  struct thread *thread)
 {
 	struct thread_runtime *tr = thread__priv(thread);

@@ -1827,6 +1831,18 @@ static void timehist_print_sample(struct perf_sched *sched,
 	if (sched->show_wakeups)
 		printf("  %-*s", comm_width, "");
 
+	if (thread->tid == 0)
+		goto out;
+
+	if (sched->show_callchain)
+		printf("  ");
+
+	sample__fprintf_sym(sample, al, 0,
+			    EVSEL__PRINT_SYM | EVSEL__PRINT_ONELINE |
+			    EVSEL__PRINT_CALLCHAIN_ARROW,
+			    &callchain_cursor, stdout);
+
+out:
 	printf("\n");
 }
 

@@ -1878,9 +1894,14 @@ static void timehist_update_runtime_stats(struct thread_runtime *r,
 	r->total_run_time += r->dt_run;
 }
 
-static bool is_idle_sample(struct perf_sample *sample,
-			   struct perf_evsel *evsel)
+static bool is_idle_sample(struct perf_sched *sched,
+			   struct perf_sample *sample,
+			   struct perf_evsel *evsel,
+			   struct machine *machine)
 {
+	struct thread *thread;
+	struct callchain_cursor *cursor = &callchain_cursor;
+
 	/* pid 0 == swapper == idle task */
 	if (sample->pid == 0)
 		return true;

@@ -1889,6 +1910,25 @@ static bool is_idle_sample(struct perf_sample *sample,
 		if (perf_evsel__intval(evsel, sample, "prev_pid") == 0)
 			return true;
 	}
+
+	/* want main thread for process - has maps */
+	thread = machine__findnew_thread(machine, sample->pid, sample->pid);
+	if (thread == NULL) {
+		pr_debug("Failed to get thread for pid %d.\n", sample->pid);
+		return false;
+	}
+
+	if (!symbol_conf.use_callchain || sample->callchain == NULL)
+		return false;
+
+	if (thread__resolve_callchain(thread, cursor, evsel, sample,
+				      NULL, NULL, sched->max_stack) != 0) {
+		if (verbose)
+			error("Failed to resolve callchain. Skipping\n");
+
+		return false;
+	}
+	callchain_cursor_commit(cursor);
 	return false;
 }
 

@@ -1999,13 +2039,14 @@ static struct thread_runtime *thread__get_runtime(struct thread *thread)
 	return tr;
 }
 
-static struct thread *timehist_get_thread(struct perf_sample *sample,
+static struct thread *timehist_get_thread(struct perf_sched *sched,
+					  struct perf_sample *sample,
 					  struct machine *machine,
 					  struct perf_evsel *evsel)
 {
 	struct thread *thread;
 
-	if (is_idle_sample(sample, evsel)) {
+	if (is_idle_sample(sched, sample, evsel, machine)) {
 		thread = get_idle_thread(sample->cpu);
 		if (thread == NULL)
 			pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);

@@ -2115,7 +2156,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
 		goto out;
 	}
 
-	thread = timehist_get_thread(sample, machine, evsel);
+	thread = timehist_get_thread(sched, sample, machine, evsel);
 	if (thread == NULL) {
 		rc = -1;
 		goto out;

@@ -2134,7 +2175,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
 
 	timehist_update_runtime_stats(tr, sample->time, tprev);
 	if (!sched->summary_only)
-		timehist_print_sample(sched, sample, thread);
+		timehist_print_sample(sched, sample, &al, thread);
 
 out:
 	if (tr) {

@@ -2327,6 +2368,30 @@ static int perf_timehist__process_sample(struct perf_tool *tool,
 	return err;
 }
 
+static int timehist_check_attr(struct perf_sched *sched,
+			       struct perf_evlist *evlist)
+{
+	struct perf_evsel *evsel;
+	struct evsel_runtime *er;
+
+	list_for_each_entry(evsel, &evlist->entries, node) {
+		er = perf_evsel__get_runtime(evsel);
+		if (er == NULL) {
+			pr_err("Failed to allocate memory for evsel runtime data\n");
+			return -1;
+		}
+
+		if (sched->show_callchain &&
+		    !(evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN)) {
+			pr_info("Samples do not have callchains.\n");
+			sched->show_callchain = 0;
+			symbol_conf.use_callchain = 0;
+		}
+	}
+
+	return 0;
+}
+
 static int perf_sched__timehist(struct perf_sched *sched)
 {
 	const struct perf_evsel_str_handler handlers[] = {

@@ -2359,6 +2424,8 @@ static int perf_sched__timehist(struct perf_sched *sched)
 	sched->tool.ordered_events = true;
 	sched->tool.ordering_requires_timestamps = true;
 
+	symbol_conf.use_callchain = sched->show_callchain;
+
 	session = perf_session__new(&file, false, &sched->tool);
 	if (session == NULL)
 		return -ENOMEM;

@@ -2367,6 +2434,9 @@ static int perf_sched__timehist(struct perf_sched *sched)
 
 	symbol__init(&session->header.env);
 
+	if (timehist_check_attr(sched, evlist) != 0)
+		goto out;
+
 	setup_pager();
 
 	/* setup per-evsel handlers */

@@ -2714,6 +2784,8 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 		.next_shortname1      = 'A',
 		.next_shortname2      = '0',
 		.skip_merge           = 0,
+		.show_callchain	      = 1,
+		.max_stack            = 5,
 	};
 	const struct option sched_options[] = {
 	OPT_STRING('i', "input", &input_name, "file",

@@ -2759,6 +2831,10 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 		   "file", "vmlinux pathname"),
 	OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
 		   "file", "kallsyms pathname"),
+	OPT_BOOLEAN('g', "call-graph", &sched.show_callchain,
+		    "Display call chains if present (default on)"),
+	OPT_UINTEGER(0, "max-stack", &sched.max_stack,
+		   "Maximum number of functions to display backtrace."),
 	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 		    "Look for files with symbols relative to this directory"),
 	OPT_BOOLEAN('s', "summary", &sched.summary_only,

index 1f8731640809..829468defa07 100644
@@ -201,6 +201,7 @@ struct perf_sched {
 	bool		summary_only;
 	bool		show_callchain;
 	unsigned int	max_stack;
+	bool		show_cpu_visual;
 	bool		show_wakeups;
 	u64		skipped_samples;
 };

@@ -1783,10 +1784,23 @@ static char *timehist_get_commstr(struct thread *thread)
 	return str;
 }
 
-static void timehist_header(void)
+static void timehist_header(struct perf_sched *sched)
 {
+	u32 ncpus = sched->max_cpu + 1;
+	u32 i, j;
+
 	printf("%15s %6s ", "time", "cpu");
 
+	if (sched->show_cpu_visual) {
+		printf(" ");
+		for (i = 0, j = 0; i < ncpus; ++i) {
+			printf("%x", j++);
+			if (j > 15)
+				j = 0;
+		}
+		printf(" ");
+	}
+
 	printf(" %-20s  %9s  %9s  %9s",
 		"task name", "wait time", "sch delay", "run time");
 

@@ -1797,6 +1811,9 @@ static void timehist_header(void)
 	 */
 	printf("%15s %-6s ", "", "");
 
+	if (sched->show_cpu_visual)
+		printf(" %*s ", ncpus, "");
+
 	printf(" %-20s  %9s  %9s  %9s\n", "[tid/pid]", "(msec)", "(msec)", "(msec)");
 
 	/*

@@ -1804,6 +1821,9 @@ static void timehist_header(void)
 	 */
 	printf("%.15s %.6s ", graph_dotted_line, graph_dotted_line);
 
+	if (sched->show_cpu_visual)
+		printf(" %.*s ", ncpus, graph_dotted_line);
+
 	printf(" %.20s  %.9s  %.9s  %.9s",
 		graph_dotted_line, graph_dotted_line, graph_dotted_line,
 		graph_dotted_line);

@@ -1817,11 +1837,28 @@ static void timehist_print_sample(struct perf_sched *sched,
 				  struct thread *thread)
 {
 	struct thread_runtime *tr = thread__priv(thread);
+	u32 max_cpus = sched->max_cpu + 1;
 	char tstr[64];
 
 	timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
 	printf("%15s [%04d] ", tstr, sample->cpu);
 
+	if (sched->show_cpu_visual) {
+		u32 i;
+		char c;
+
+		printf(" ");
+		for (i = 0; i < max_cpus; ++i) {
+			/* flag idle times with 'i'; others are sched events */
+			if (i == sample->cpu)
+				c = (thread->tid == 0) ? 'i' : 's';
+			else
+				c = ' ';
+			printf("%c", c);
+		}
+		printf(" ");
+	}
+
 	printf(" %-*s ", comm_width, timehist_get_commstr(thread));
 
 	print_sched_time(tr->dt_wait, 6);

@@ -2095,6 +2132,8 @@ static void timehist_print_wakeup_event(struct perf_sched *sched,
 
 	timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
 	printf("%15s [%04d] ", tstr, sample->cpu);
+	if (sched->show_cpu_visual)
+		printf(" %*s ", sched->max_cpu + 1, "");
 
 	printf(" %-*s ", comm_width, timehist_get_commstr(thread));
 

@@ -2458,7 +2497,7 @@ static int perf_sched__timehist(struct perf_sched *sched)
 		sched->summary = sched->summary_only;
 
 	if (!sched->summary_only)
-		timehist_header();
+		timehist_header(sched);
 
 	err = perf_session__process_events(session);
 	if (err) {

@@ -2842,6 +2881,7 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
 	OPT_BOOLEAN('S', "with-summary", &sched.summary,
 		    "Show all syscalls and summary with statistics"),
 	OPT_BOOLEAN('w', "wakeups", &sched.show_wakeups, "Show wakeup events"),
+	OPT_BOOLEAN('V', "cpu-visual", &sched.show_cpu_visual, "Add CPU visual"),
 	OPT_PARENT(sched_options)
 	};