diff --git a/Documentation/libtraceeval-delta-rest.txt b/Documentation/libtraceeval-delta-rest.txt
new file mode 100644
index 000000000000..3b056fd480cc
--- /dev/null
+++ b/Documentation/libtraceeval-delta-rest.txt
@@ -0,0 +1,308 @@
+libtraceeval(3)
+===============
+
+NAME
+----
+traceeval_delta_stat, traceeval_delta_stat_size, traceeval_delta_teval_get,
+traceeval_delta_teval_put, traceeval_iterator_delta_stat - Reading the libtraceeval_data elements
+
+SYNOPSIS
+--------
+[verse]
+--
+*#include <traceeval.h>*
+
+struct traceeval_stat pass:[*]*traceeval_delta_stat*(struct traceeval_delta pass:[*]_tdelta_,
+						 const struct traceeval_data pass:[*]_keys_)
+struct traceeval_stat pass:[*]*traceeval_delta_stat_size*(struct traceeval_delta pass:[*]_tdelta_,
+						 const struct traceeval_data pass:[*]_keys_,
+						 size_t _nr_keys_);
+
+struct traceeval pass:[*]*traceeval_delta_teval_get*(struct traceeval_delta pass:[*]_tdelta_);
+
+void *traceeval_delta_teval_put*(struct traceeval pass:[*]_teval_);
+
+struct traceeval_stat pass:[*]*traceeval_iterator_delta_stat*(struct traceeval_iterator pass:[*]_iter_);
+--
+
+DESCRIPTION
+-----------
+The traceeval_delta is used to record the time deltas between events. These
+functions help show that information that was recorded.
+
+The *traceeval_delta_stat()* function will return a traceeval_stat descriptor
+(see *traceeval_stat*(3)) for the time delta that it recorded for the element
+represented by _keys_. The delta is calculated from various calls to
+*traceeval_delta_start*(3) and *traceeval_delta_stop*(3). Since the delta field
+of a traceeval_delta is not visible from other routines (nor is it name), the
+way to get the information for the delta is via the *traceeval_delta_stat()*
+function.
+
+The *traceeval_delta_stat()* requires _keys_ to be a static array, if it is a
+dynamic array, then *traceeval_delta_stat_size()* must be used instead. This function
+provides a parameter, _nr_keys_, to specify how many elements _keys_ has. Note that
+_keys_ must be the same size as the keys passed to *traceeval_delta_init*(3).
+
+The traceeval_delta does not provide any direct means to use an iterator, so
+a handle to its internal traceeval can be used for this purpose with
+*traceeval_delta_teval_get()*. This will return the internal traceeval handle for
+the given _tdelta traceeval_delta descriptor. The returned traceeval should only
+be used with iterators, as other functions that take a traceeval descriptor will
+likely have undefined results if used.
+
+When finished with the traceeval handle retrieved from traceeval_delta_teval_get(),
+the _teval_ should be passed to *traceeval_delta_teval_put()* to clean up any
+resources that were allocated.
+
+Because the delta stored in traceeval_delta is hidden, when using an iterator on
+a traceeval that came from *traceeval_delta_teval_get()*, the *traceeval_iterator_delta_stat()*
+can be used to retrieve the traceeval_stat that represents the internal delta
+of the traceeval_delta the traceeval the iterator is using came from.
+
+RETURN VALUE
+------------
+The *traceeval_iterator_get()* returns a traceeval_iterator descriptor that will iterate
+over the given _teval_ on success, and NULL on error.
+
+The *traceeval_iterator_sort()* and traceeval_iterator_sort_custom()* return 0 on success and -1 or error.
+
+The *traceeval_iterator_next()* returns 1 when it reads a new element from the traceeval and places the element's
+keys into _keys_. It returns 0 when there's no more elements to read and -1 on error.
+
+The *traceeval_iterator_query()* returns 1 if it successfully reads the current element from the
+*traceeval_iterator_next()* and places the values in _results_. It returns 0 if there are no more elements,
+and -1 on error.
+
+The *traceeval_iterator_stat()* returns a descriptor for the current element's given _field_ on success and
+NULL if there are no current elements or the _field_ is not a valid stat type.
+
+The *traceeval_iterator_remove()* returns 1 if the current element was successfully removed, or 0
+if there was no element (called before *traceeval_iterator_next()*).
+
+EXAMPLE
+-------
+[source,c]
+--
+#include <trace-cmd.h>
+#include <traceeval.h>
+
+static struct traceeval_type task_types[] = {
+	{
+		.name		= "COMM",
+		.type		= TRACEEVAL_TYPE_STRING,
+	},
+	{
+		.name		= "PID",
+		.type		= TRACEEVAL_TYPE_NUMBER,
+	}
+};
+
+static struct traceeval_type cpu_types[] = {
+	{
+		.name		= "CPU",
+		.type		= TRACEEVAL_TYPE_NUMBER,
+	}
+};
+
+struct data {
+	struct traceeval_delta		*tdelta_tasks;
+	struct traceeval_delta		*tdelta_cpus;
+};
+
+static struct tep_format_field *get_field(struct tep_event *event, const char *name)
+{
+	static struct tep_format_field *field;
+
+	field = tep_find_field(event, name);
+	if (!field) {
+		fprintf(stderr, "Could not find field %s for %s", name, event->name);
+		exit(-1);
+	}
+
+	return field;
+}
+
+static int switch_func(struct tracecmd_input *handle, struct tep_event *event,
+		       struct tep_record *record, int cpu, void *d)
+{
+	static struct tep_format_field *prev_comm;
+	static struct tep_format_field *prev_pid;
+	static struct tep_format_field *next_comm;
+	static struct tep_format_field *next_pid;
+	struct traceeval_data task_keys[2];
+	struct traceeval_data cpu_keys[1];
+	struct data *data = d;
+	unsigned long long val;
+	const char *comm;
+
+	if (!next_comm) {
+		prev_comm = get_field(event, "prev_comm");
+		prev_pid = get_field(event, "prev_pid");
+
+		next_comm = get_field(event, "next_comm");
+		next_pid = get_field(event, "next_pid");
+	}
+
+	comm = record->data + prev_comm->offset;
+	tep_read_number_field(prev_pid, record->data, &val);
+
+	TRACEEVAL_SET_CSTRING(task_keys[0], comm);
+	TRACEEVAL_SET_NUMBER(task_keys[1], val);
+
+	if (val)
+		traceeval_delta_stop(data->tdelta_tasks, task_keys, record->ts);
+
+	comm = record->data + next_comm->offset;
+	tep_read_number_field(next_pid, record->data, &val);
+
+	TRACEEVAL_SET_CSTRING(task_keys[0], comm);
+	TRACEEVAL_SET_NUMBER(task_keys[1], val);
+
+	TRACEEVAL_SET_NUMBER(cpu_keys[0], record->cpu);
+
+	if (val) {
+		if (traceeval_delta_start(data->tdelta_tasks, task_keys, record->ts) < 0)
+			printf("FAILED\n");
+		traceeval_delta_continue(data->tdelta_cpus, cpu_keys, record->ts);
+	} else {
+		traceeval_delta_stop(data->tdelta_cpus, cpu_keys, record->ts);
+	}
+
+	return 0;
+}
+
+static void print_microseconds(int idx, unsigned long long nsecs)
+{
+	unsigned long long usecs;
+
+	usecs = nsecs / 1000;
+	if (!nsecs || usecs)
+		printf("%*lld", idx, usecs);
+	else
+		printf("%*d.%03lld", idx, 0, nsecs);
+}
+
+static void print_stat(struct traceeval_stat *stat)
+{
+	unsigned long long total;
+	unsigned long long cnt;
+	unsigned long long ts;
+
+	printf("\tmax: ");
+	print_microseconds(12, traceeval_stat_max_timestamp(stat, &ts));
+	printf("  timestamp: ");
+	print_microseconds(10, ts);
+	printf("\n\tmin: ");
+	print_microseconds(12, traceeval_stat_min_timestamp(stat, &ts));
+	printf("  timestamp: ");
+	print_microseconds(10, ts);
+	printf("\n\ttotal: ");
+	total = traceeval_stat_total(stat);
+	print_microseconds(10, total);
+	cnt = traceeval_stat_count(stat);
+	printf("\n\tcount: %*lld\n", 10, cnt);
+	printf("\taverage:");
+	print_microseconds(9, cnt ? total / cnt : 0);
+	printf("\n");
+}
+
+static void display_cpus(struct traceeval_delta *tdelta)
+{
+	struct traceeval *teval = traceeval_delta_teval_get(tdelta);
+	struct traceeval_iterator *iter = traceeval_iterator_get(teval);
+	const struct traceeval_data *keys;
+
+	printf("\n");
+
+	traceeval_iterator_sort(iter, cpu_types[0].name, 0, true);
+
+	while (traceeval_iterator_next(iter, &keys) > 0) {
+		struct traceeval_stat *stat;
+
+		stat = traceeval_iterator_delta_stat(iter);
+
+		printf("CPU [%zd]:\n", keys[0].number);
+		print_stat(stat);
+	}
+	traceeval_delta_teval_put(teval);
+}
+
+static void display_tasks(struct traceeval_delta *tdelta)
+{
+	struct traceeval *teval = traceeval_delta_teval_get(tdelta);
+	struct traceeval_iterator *iter = traceeval_iterator_get(teval);
+	const struct traceeval_data *keys;
+
+	printf("\n");
+
+	traceeval_iterator_sort(iter, task_types[0].name, 0, true);
+	traceeval_iterator_sort(iter, task_types[1].name, 1, true);
+
+	while (traceeval_iterator_next(iter, &keys) > 0) {
+		struct traceeval_stat *stat;
+
+		stat = traceeval_iterator_delta_stat(iter);
+
+		printf("Task %s [%zd]:\n", keys[0].cstring, keys[1].number);
+		print_stat(stat);
+	}
+
+	traceeval_delta_teval_put(teval);
+};
+
+int main (int argc, char **argv)
+{
+	struct tracecmd_input *handle;
+	struct data data;
+
+	if (argc < 2) {
+		printf("Need to pass trace.dat file to this\n");
+		exit(-1);
+	}
+
+	handle = tracecmd_open(argv[1], TRACECMD_FL_LOAD_NO_PLUGINS);
+
+	data.tdelta_tasks = traceeval_delta_init(task_types, NULL);
+	data.tdelta_cpus = traceeval_delta_init(cpu_types, NULL);
+
+	tracecmd_follow_event(handle, "sched", "sched_switch", switch_func, &data);
+	tracecmd_iterate_events(handle, NULL, 0, NULL, NULL);
+
+	display_cpus(data.tdelta_cpus);
+	display_tasks(data.tdelta_tasks);
+
+	traceeval_delta_release(data.tdelta_cpus);
+	traceeval_delta_release(data.tdelta_tasks);
+
+	return 0;
+}
+--
+
+FILES
+-----
+[verse]
+--
+*traceval.h*
+	Header file to include in order to have access to the library APIs.
+*-ltraceeval*
+	Linker switch to add when building a program that uses the library.
+--
+
+SEE ALSO
+--------
+*libtraceeval*(3)
+
+AUTHOR
+------
+[verse]
+--
+*Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceeval*.
+--
+REPORTING BUGS
+--------------
+Report bugs to  <linux-trace-devel@vger.kernel.org>
+
+LICENSE
+-------
+libtraceeval is licensed under MIT.
+
diff --git a/Documentation/libtraceeval.txt b/Documentation/libtraceeval.txt
index 68fc182f7c46..f30d427255e1 100644
--- a/Documentation/libtraceeval.txt
+++ b/Documentation/libtraceeval.txt
@@ -125,6 +125,20 @@ Handling insertion, deletion and querying of traceeval_delta elements:
 
 	void *traceeval_delta_results_release*(struct traceeval_delta pass:[*]_tdelta_,
 				     const struct traceeval_data pass:[*]_results_);
+
+Handling reading the deltas of a traceeval_delta:
+	struct traceeval_stat pass:[*]*traceeval_delta_stat*(struct traceeval_delta pass:[*]_tdelta_,
+						 const struct traceeval_data pass:[*]_keys_)
+	struct traceeval_stat pass:[*]*traceeval_delta_stat_size*(struct traceeval_delta pass:[*]_tdelta_,
+						 const struct traceeval_data pass:[*]_keys_,
+						 size_t _nr_keys_);
+
+	struct traceeval pass:[*]*traceeval_delta_teval_get*(struct traceeval_delta pass:[*]_tdelta_);
+
+	void *traceeval_delta_teval_put*(struct traceeval_delta pass:[*]_tdelta_,
+			       struct traceeval pass:[*]_teval_);
+
+	struct traceeval_stat pass:[*]*traceeval_iterator_delta_stat*(struct traceeval_iterator pass:[*]_iter_);
 --
 
 DESCRIPTION
