hrt: remove hrt_elapsed_time_atomic

There's no protection on posix

platforms/common/uORB/uORB_tests/uORBTest_UnitTest.cpp

@@ -83,7 +83,7 @@ int uORBTest::UnitTest::pubsublatency_main()
 		if (fds[0].revents & POLLIN) {
 			orb_copy(ORB_ID(orb_test_medium), test_multi_sub, &t);
 
-			unsigned elt = (unsigned)hrt_elapsed_time_atomic(&t.timestamp);
+			unsigned elt = (unsigned)hrt_elapsed_time(&t.timestamp);
 			latency_integral += elt;
 			timings[i] = elt;
 

platforms/nuttx/src/px4/nxp/imxrt/hrt/hrt.c

@@ -586,21 +586,6 @@ abstime_to_ts(struct timespec *ts, hrt_abstime abstime)
 	ts->tv_nsec = abstime * 1000;
 }
 
-/**
- * Compare a time value with the current time as atomic operation.
- */
-hrt_abstime
-hrt_elapsed_time_atomic(const volatile hrt_abstime *then)
-{
-	irqstate_t flags = px4_enter_critical_section();
-
-	hrt_abstime delta = hrt_absolute_time() - *then;
-
-	px4_leave_critical_section(flags);
-
-	return delta;
-}
-
 /**
  * Store the absolute time in an interrupt-safe fashion
  */

platforms/nuttx/src/px4/nxp/kinetis/hrt/hrt.c

@@ -598,21 +598,6 @@ abstime_to_ts(struct timespec *ts, hrt_abstime abstime)
 	ts->tv_nsec = abstime * 1000;
 }
 
-/**
- * Compare a time value with the current time as atomic operation.
- */
-hrt_abstime
-hrt_elapsed_time_atomic(const volatile hrt_abstime *then)
-{
-	irqstate_t flags = px4_enter_critical_section();
-
-	hrt_abstime delta = hrt_absolute_time() - *then;
-
-	px4_leave_critical_section(flags);
-
-	return delta;
-}
-
 /**
  * Store the absolute time in an interrupt-safe fashion
  */

platforms/nuttx/src/px4/nxp/s32k1xx/hrt/hrt.c

@@ -634,21 +634,6 @@ abstime_to_ts(struct timespec *ts, hrt_abstime abstime)
 	ts->tv_nsec = abstime * 1000;
 }
 
-/**
- * Compare a time value with the current time as atomic operation.
- */
-hrt_abstime
-hrt_elapsed_time_atomic(const volatile hrt_abstime *then)
-{
-	irqstate_t flags = px4_enter_critical_section();
-
-	hrt_abstime delta = hrt_absolute_time() - *then;
-
-	px4_leave_critical_section(flags);
-
-	return delta;
-}
-
 /**
  * Store the absolute time in an interrupt-safe fashion
  */

platforms/nuttx/src/px4/stm/stm32_common/hrt/hrt.c

@@ -719,21 +719,6 @@ abstime_to_ts(struct timespec *ts, hrt_abstime abstime)
 	ts->tv_nsec = abstime * 1000;
 }
 
-/**
- * Compare a time value with the current time as atomic operation
- */
-hrt_abstime
-hrt_elapsed_time_atomic(const volatile hrt_abstime *then)
-{
-	irqstate_t flags = px4_enter_critical_section();
-
-	hrt_abstime delta = hrt_absolute_time() - *then;
-
-	px4_leave_critical_section(flags);
-
-	return delta;
-}
-
 /**
  * Store the absolute time in an interrupt-safe fashion
  */

platforms/posix/src/px4/common/drv_hrt.cpp

@@ -157,20 +157,6 @@ hrt_abstime ts_to_abstime(const struct timespec *ts)
 	return result;
 }
 
-/*
- * Compute the delta between a timestamp taken in the past
- * and now.
- *
- * This function is safe to use even if the timestamp is updated
- * by an interrupt during execution.
- */
-hrt_abstime hrt_elapsed_time_atomic(const volatile hrt_abstime *then)
-{
-	// This is not atomic as the value on the application layer of POSIX is limited.
-	hrt_abstime delta = hrt_absolute_time() - *then;
-	return delta;
-}
-
 /*
  * Store the absolute time in an interrupt-safe fashion.
  *

src/drivers/drv_hrt.h

@@ -110,15 +110,6 @@ static inline hrt_abstime hrt_elapsed_time(const hrt_abstime *then)
 	return hrt_absolute_time() - *then;
 }
 
-/**
- * Compute the delta between a timestamp taken in the past
- * and now.
- *
- * This function is safe to use even if the timestamp is updated
- * by an interrupt during execution.
- */
-__EXPORT extern hrt_abstime hrt_elapsed_time_atomic(const volatile hrt_abstime *then);
-
 /**
  * Store the absolute time in an interrupt-safe fashion.
  *

src/systemcmds/microbench/test_microbench_hrt.cpp

@@ -144,7 +144,6 @@ bool MicroBenchHRT::time_px4_hrt()
 {
 	PERF("hrt_absolute_time()", u_64_out = hrt_absolute_time(), 1000);
 	PERF("hrt_elapsed_time()", u_64_out = hrt_elapsed_time(&u_64), 1000);
-	PERF("hrt_elapsed_time_atomic()", u_64_out = hrt_elapsed_time_atomic(&u_64), 1000);
 
 	return true;
 }

src/systemcmds/tests/hrt_test/hrt_test.cpp

@@ -71,13 +71,13 @@ int HRTTest::main()
 
 	hrt_abstime t = hrt_absolute_time();
 	px4_usleep(1000000);
-	hrt_abstime elt = hrt_elapsed_time_atomic(&t);
+	hrt_abstime elt = hrt_elapsed_time(&t);
 	PX4_INFO("Elapsed time %llu in 1 sec (usleep)\n", (unsigned long long)elt);
 	PX4_INFO("Start time %llu\n", (unsigned long long)t);
 
 	t = hrt_absolute_time();
 	px4_sleep(1);
-	elt = hrt_elapsed_time_atomic(&t);
+	elt = hrt_elapsed_time(&t);
 	PX4_INFO("Elapsed time %llu in 1 sec (sleep)\n", (unsigned long long)elt);
 	PX4_INFO("Start time %llu\n", (unsigned long long)t);