ticker_api: Code clarification

* update_interrupt renamed into schedule_interrupt
* update_current_timestamp renamed into update_present_time
* ticker_event_queue_t::timestamp renamed into
* ticker_event_queue_t::present_time
* Fix doxygen comments in ticker_api.h
* Update comments internal comments in mbed_ticker_api.c
pull/4094/head
Vincent Coubard 2017-05-15 17:08:53 +01:00
parent c20a1ccd4f
commit aeffd738c7
3 changed files with 92 additions and 85 deletions

View File

@ -100,7 +100,7 @@ static ticker_event_queue_t queue_stub = {
static void reset_queue_stub() {
queue_stub.event_handler = NULL;
queue_stub.head = NULL,
queue_stub.timestamp = 0;
queue_stub.present_time = 0;
queue_stub.initialized = false;
}
@ -174,7 +174,7 @@ static void test_ticker_initialization() {
TEST_ASSERT_TRUE(interface_stub.initialized);
TEST_ASSERT_EQUAL_PTR(dummy_handler, queue_stub.event_handler);
TEST_ASSERT_EQUAL_UINT64(interface_stub.timestamp, queue_stub.timestamp);
TEST_ASSERT_EQUAL_UINT64(interface_stub.timestamp, queue_stub.present_time);
TEST_ASSERT_EQUAL(1, interface_stub.set_interrupt_call);
TEST_ASSERT_EQUAL_UINT32(
interface_stub.timestamp + TIMESTAMP_MAX_DELTA,
@ -437,7 +437,7 @@ static void test_legacy_insert_event_overflow() {
TIMESTAMP_MAX_DELTA +
1;
const us_timestamp_t expected_us_timestamp =
(((queue_stub.timestamp >> 32) + 1) << 32) | expected_timestamp;
(((queue_stub.present_time >> 32) + 1) << 32) | expected_timestamp;
const uint32_t expected_id = 0xDEADDEAF;
ticker_insert_event(
@ -792,12 +792,12 @@ static void test_insert_event_us_outside_overflow_range() {
ticker_set_handler(&ticker_stub, NULL);
interface_stub.set_interrupt_call = 0;
interface_stub.timestamp = 0xAAAAAAAA;
queue_stub.timestamp = 10ULL << 32 | interface_stub.timestamp;
queue_stub.present_time = 10ULL << 32 | interface_stub.timestamp;
// test the end of the range
ticker_event_t last_event = { 0 };
const us_timestamp_t timestamp_last_event =
queue_stub.timestamp + TIMESTAMP_MAX_DELTA;
queue_stub.present_time + TIMESTAMP_MAX_DELTA;
const uint32_t id_last_event = 0xDEADDEAF;
ticker_insert_event_us(
@ -816,7 +816,7 @@ static void test_insert_event_us_outside_overflow_range() {
// test the beginning of the range
ticker_event_t first_event = { 0 };
const us_timestamp_t timestamp_first_event = queue_stub.timestamp + 1;
const us_timestamp_t timestamp_first_event = queue_stub.present_time + 1;
const uint32_t id_first_event = 0xAAAAAAAA;
ticker_insert_event_us(
@ -852,7 +852,7 @@ static void test_insert_event_us_in_overflow_range() {
ticker_set_handler(&ticker_stub, NULL);
interface_stub.set_interrupt_call = 0;
interface_stub.timestamp = 0xAAAAAAAA;
queue_stub.timestamp = 10ULL << 32 | interface_stub.timestamp;
queue_stub.present_time = 10ULL << 32 | interface_stub.timestamp;
// test the end of the range
ticker_event_t last_event = { 0 };
@ -876,11 +876,11 @@ static void test_insert_event_us_in_overflow_range() {
// test the beginning of the range
++interface_stub.timestamp;
++queue_stub.timestamp;
++queue_stub.present_time;
ticker_event_t first_event = { 0 };
const us_timestamp_t timestamp_first_event =
queue_stub.timestamp + TIMESTAMP_MAX_DELTA + 1;
queue_stub.present_time + TIMESTAMP_MAX_DELTA + 1;
uint32_t id_first_event = 0xAAAAAAAA;
ticker_insert_event_us(&ticker_stub,
@ -914,11 +914,11 @@ static void test_insert_event_us_underflow() {
interface_stub.set_interrupt_call = 0;
interface_stub.timestamp = 0xAAAAAAAA;
queue_stub.timestamp = 10ULL << 32 | interface_stub.timestamp;
queue_stub.present_time = 10ULL << 32 | interface_stub.timestamp;
// test the end of the range
ticker_event_t event = { 0 };
const timestamp_t expected_timestamp = queue_stub.timestamp - 1;
const timestamp_t expected_timestamp = queue_stub.present_time - 1;
const uint32_t expected_id = 0xDEADDEAF;
ticker_insert_event_us(
@ -951,16 +951,16 @@ static void test_insert_event_us_head() {
ticker_set_handler(&ticker_stub, NULL);
interface_stub.set_interrupt_call = 0;
interface_stub.timestamp = 0xAAAAAAAA;
queue_stub.timestamp = 10ULL << 32 | interface_stub.timestamp;
queue_stub.present_time = 10ULL << 32 | interface_stub.timestamp;
const us_timestamp_t timestamps[] = {
UINT64_MAX,
queue_stub.timestamp + TIMESTAMP_MAX_DELTA + 1,
queue_stub.timestamp + TIMESTAMP_MAX_DELTA,
queue_stub.timestamp + (TIMESTAMP_MAX_DELTA / 2),
queue_stub.timestamp + (TIMESTAMP_MAX_DELTA / 4),
queue_stub.timestamp + (TIMESTAMP_MAX_DELTA / 8),
queue_stub.timestamp + (TIMESTAMP_MAX_DELTA / 16),
queue_stub.present_time + TIMESTAMP_MAX_DELTA + 1,
queue_stub.present_time + TIMESTAMP_MAX_DELTA,
queue_stub.present_time + (TIMESTAMP_MAX_DELTA / 2),
queue_stub.present_time + (TIMESTAMP_MAX_DELTA / 4),
queue_stub.present_time + (TIMESTAMP_MAX_DELTA / 8),
queue_stub.present_time + (TIMESTAMP_MAX_DELTA / 16),
};
ticker_event_t events[MBED_ARRAY_SIZE(timestamps)] = { 0 };
@ -971,14 +971,14 @@ static void test_insert_event_us_head() {
);
TEST_ASSERT_EQUAL_PTR(&events[i], queue_stub.head);
if ((timestamps[i] - queue_stub.timestamp) < TIMESTAMP_MAX_DELTA) {
if ((timestamps[i] - queue_stub.present_time) < TIMESTAMP_MAX_DELTA) {
TEST_ASSERT_EQUAL_UINT32(
timestamps[i],
interface_stub.interrupt_timestamp
);
} else {
TEST_ASSERT_EQUAL_UINT32(
queue_stub.timestamp + TIMESTAMP_MAX_DELTA,
queue_stub.present_time + TIMESTAMP_MAX_DELTA,
interface_stub.interrupt_timestamp
);
}
@ -1464,7 +1464,7 @@ static void test_overflow_event_update() {
interface_stub.set_interrupt_call = 0;
for (size_t i = 0; i < 8; ++i) {
us_timestamp_t previous_timestamp = queue_stub.timestamp;
us_timestamp_t previous_timestamp = queue_stub.present_time;
timestamp_t interface_timestamp =
previous_timestamp + (TIMESTAMP_MAX_DELTA + i * 100);
interface_stub.timestamp = interface_timestamp;
@ -1505,7 +1505,7 @@ static void test_overflow_event_update_when_spurious_interrupt() {
interface_stub.set_interrupt_call = 0;
for (size_t i = 0; i < 8; ++i) {
us_timestamp_t previous_timestamp = queue_stub.timestamp;
us_timestamp_t previous_timestamp = queue_stub.present_time;
timestamp_t interface_timestamp =
previous_timestamp + (TIMESTAMP_MAX_DELTA / (2 + i));
interface_stub.timestamp = interface_timestamp;

View File

@ -18,10 +18,8 @@
#include "hal/ticker_api.h"
#include "platform/mbed_critical.h"
#define MBED_MIN(x,y) (((x)<(y))?(x):(y))
static void update_interrupt(const ticker_data_t *const ticker);
static void update_current_timestamp(const ticker_data_t *const ticker);
static void schedule_interrupt(const ticker_data_t *const ticker);
static void update_present_time(const ticker_data_t *const ticker);
/*
* Initialize a ticker instance.
@ -38,11 +36,11 @@ static void initialize(const ticker_data_t *ticker)
ticker->queue->event_handler = NULL;
ticker->queue->head = NULL;
ticker->queue->timestamp = 0;
ticker->queue->present_time = 0;
ticker->queue->initialized = true;
update_current_timestamp(ticker);
update_interrupt(ticker);
update_present_time(ticker);
schedule_interrupt(ticker);
}
/**
@ -54,22 +52,29 @@ static void set_handler(const ticker_data_t *const ticker, ticker_event_handler
}
/*
* Convert a low res timestamp to a high res timestamp. An high resolution
* timestamp is used as the reference point to convert the low res timestamp
* into an high res one.
* Convert a 32 bit timestamp into a 64 bit timestamp.
*
* A 64 bit timestamp is used as the point of time of reference while the
* timestamp to convert is relative to this point of time.
*
* The lower 32 bits of the timestamp returned will be equal to the timestamp to
* convert.
*
* It is important to note that the result will **never** be in the past. If the
* value of the low res timetamp is less than the low res part of the reference
* timestamp then an overflow is
*
* @param ref: The timestamp of reference.
* @param relative_timestamp: The timestamp to convert.
* If the timestamp to convert is less than the lower 32 bits of the time
* reference then the timestamp to convert is seen as an overflowed value and
* the upper 32 bit of the timestamp returned will be equal to the upper 32 bit
* of the reference point + 1.
* Otherwise, the upper 32 bit returned will be equal to the upper 32 bit of the
* reference point.
*
* @param ref: The 64 bit timestamp of reference.
* @param timestamp: The timestamp to convert.
*/
static us_timestamp_t convert_relative_timestamp(us_timestamp_t ref, timestamp_t relative_timestamp)
static us_timestamp_t convert_timestamp(us_timestamp_t ref, timestamp_t timestamp)
{
bool overflow = relative_timestamp < ((timestamp_t) ref) ? true : false;
bool overflow = timestamp < ((timestamp_t) ref) ? true : false;
us_timestamp_t result = (ref & ~((us_timestamp_t)UINT32_MAX)) | relative_timestamp;
us_timestamp_t result = (ref & ~((us_timestamp_t)UINT32_MAX)) | timestamp;
if (overflow) {
result += (1ULL<<32);
}
@ -78,38 +83,42 @@ static us_timestamp_t convert_relative_timestamp(us_timestamp_t ref, timestamp_t
}
/**
* update the current timestamp value of a ticker.
* Update the present timestamp value of a ticker.
*/
static void update_current_timestamp(const ticker_data_t *const ticker)
static void update_present_time(const ticker_data_t *const ticker)
{
ticker->queue->timestamp = convert_relative_timestamp(
ticker->queue->timestamp,
ticker->queue->present_time = convert_timestamp(
ticker->queue->present_time,
ticker->interface->read()
);
}
/**
* update the interrupt with the appropriate timestamp.
* if there is no interrupt scheduled or the next event to execute is in more
* than MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA us from now then the
* interrupt will be set to MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA us from now.
* Otherwise the interrupt will be set to head->timestamp - queue->timestamp us.
* Compute the time when the interrupt has to be triggered and schedule it.
*
* If there is no event in the queue or the next event to execute is in more
* than MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA us from now then the ticker
* irq will be scheduled in MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA us.
* Otherwise the irq will be scheduled to happen when the running counter reach
* the timestamp of the first event in the queue.
*
* @note If there is no event in the queue then the interrupt is scheduled to
* in MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA. This is necessary to keep track
* of the timer overflow.
*/
static void update_interrupt(const ticker_data_t *const ticker)
static void schedule_interrupt(const ticker_data_t *const ticker)
{
update_current_timestamp(ticker);
uint32_t diff = MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA;
update_present_time(ticker);
uint32_t duration = MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA;
if (ticker->queue->head) {
diff = MBED_MIN(
(ticker->queue->head->timestamp - ticker->queue->timestamp),
MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA
);
if (ticker->queue->head) {
us_timestamp_t event_interval = (ticker->queue->head->timestamp - ticker->queue->present_time);
if (event_interval < MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA) {
duration = event_interval;
}
}
ticker->interface->set_interrupt(
ticker->queue->timestamp + diff
);
ticker->interface->set_interrupt(ticker->queue->present_time + duration);
}
void ticker_set_handler(const ticker_data_t *const ticker, ticker_event_handler handler)
@ -129,9 +138,9 @@ void ticker_irq_handler(const ticker_data_t *const ticker)
}
// update the current timestamp used by the queue
update_current_timestamp(ticker);
update_present_time(ticker);
if (ticker->queue->head->timestamp <= ticker->queue->timestamp) {
if (ticker->queue->head->timestamp <= ticker->queue->present_time) {
// This event was in the past:
// point to the following one and execute its handler
ticker_event_t *p = ticker->queue->head;
@ -146,18 +155,17 @@ void ticker_irq_handler(const ticker_data_t *const ticker)
}
}
update_interrupt(ticker);
schedule_interrupt(ticker);
}
void ticker_insert_event(const ticker_data_t *const ticker, ticker_event_t *obj, timestamp_t timestamp, uint32_t id)
{
/* disable interrupts for the duration of the function */
core_util_critical_section_enter();
// update the current timestamp
update_current_timestamp(ticker);
us_timestamp_t absolute_timestamp = convert_relative_timestamp(
ticker->queue->timestamp,
update_present_time(ticker);
us_timestamp_t absolute_timestamp = convert_timestamp(
ticker->queue->present_time,
timestamp
);
core_util_critical_section_exit();
@ -171,15 +179,14 @@ void ticker_insert_event(const ticker_data_t *const ticker, ticker_event_t *obj,
void ticker_insert_event_us(const ticker_data_t *const ticker, ticker_event_t *obj, us_timestamp_t timestamp, uint32_t id)
{
/* disable interrupts for the duration of the function */
core_util_critical_section_enter();
// update the current timestamp
update_current_timestamp(ticker);
update_present_time(ticker);
// filter out timestamp in the past
if (timestamp < ticker->queue->timestamp) {
update_interrupt(ticker);
if (timestamp < ticker->queue->present_time) {
schedule_interrupt(ticker);
return;
}
@ -211,7 +218,7 @@ void ticker_insert_event_us(const ticker_data_t *const ticker, ticker_event_t *o
prev->next = obj;
}
update_interrupt(ticker);
schedule_interrupt(ticker);
core_util_critical_section_exit();
}
@ -224,7 +231,7 @@ void ticker_remove_event(const ticker_data_t *const ticker, ticker_event_t *obj)
if (ticker->queue->head == obj) {
// first in the list, so just drop me
ticker->queue->head = obj->next;
update_interrupt(ticker);
schedule_interrupt(ticker);
} else {
// find the object before me, then drop me
ticker_event_t* p = ticker->queue->head;
@ -247,8 +254,8 @@ timestamp_t ticker_read(const ticker_data_t *const ticker)
us_timestamp_t ticker_read_us(const ticker_data_t *const ticker)
{
update_current_timestamp(ticker);
return ticker->queue->timestamp;
update_present_time(ticker);
return ticker->queue->present_time;
}
int ticker_get_next_timestamp(const ticker_data_t *const data, timestamp_t *timestamp)

View File

@ -67,7 +67,7 @@ typedef struct {
typedef struct {
ticker_event_handler event_handler; /**< Event handler */
ticker_event_t *head; /**< A pointer to head */
us_timestamp_t timestamp; /**< Store the last timestamp used */
us_timestamp_t present_time; /**< Store the timestamp used for present time */
bool initialized; /**< Indicate if the instance is initialized */
} ticker_event_queue_t;
@ -89,20 +89,20 @@ extern "C" {
/** Initialize a ticker and set the event handler
*
* @param data The ticker's data
* @param ticker The ticker object.
* @param handler A handler to be set
*/
void ticker_set_handler(const ticker_data_t *const ticker, ticker_event_handler handler);
/** IRQ handler that goes through the events to trigger overdue events.
*
* @param data The ticker's data
* @param ticker The ticker object.
*/
void ticker_irq_handler(const ticker_data_t *const ticker);
/** Remove an event from the queue
*
* @param data The ticker's data
* @param ticker The ticker object.
* @param obj The event object to be removed from the queue
*/
void ticker_remove_event(const ticker_data_t *const ticker, ticker_event_t *obj);
@ -120,7 +120,7 @@ void ticker_remove_event(const ticker_data_t *const ticker, ticker_event_t *obj)
* @note prefer the use of ticker_insert_event_us which allows registration of
* absolute timestamp.
*
* @param data The ticker's data
* @param ticker The ticker object.
* @param obj The event object to be inserted to the queue
* @param timestamp The event's timestamp
* @param id The event object
@ -134,7 +134,7 @@ void ticker_insert_event(const ticker_data_t *const ticker, ticker_event_t *obj,
* @warning If an event is inserted with a timestamp less than the current
* timestamp then the event will **not** be inserted.
*
* @param data The ticker's data
* @param ticker The ticker object.
* @param obj The event object to be inserted to the queue
* @param timestamp The event's timestamp
* @param id The event object
@ -146,7 +146,7 @@ void ticker_insert_event_us(const ticker_data_t *const ticker, ticker_event_t *o
* @warning Return a relative timestamp because the counter wrap every 4294
* seconds.
*
* @param data The ticker's data
* @param ticker The ticker object.
* @return The current timestamp
*/
timestamp_t ticker_read(const ticker_data_t *const ticker);
@ -156,14 +156,14 @@ timestamp_t ticker_read(const ticker_data_t *const ticker);
* @warning Return an absolute timestamp counting from the initialization of the
* ticker.
*
* @param data The ticker's data
* @param ticker The ticker object.
* @return The current timestamp
*/
us_timestamp_t ticker_read_us(const ticker_data_t *const ticker);
/** Read the next event's timestamp
*
* @param data The ticker's data
* @param ticker The ticker object.
* @return 1 if timestamp is pending event, 0 if there's no event pending
*/
int ticker_get_next_timestamp(const ticker_data_t *const ticker, timestamp_t *timestamp);