From 21429f681dfc94881b5d26763102c1e604889a24 Mon Sep 17 00:00:00 2001 From: Kinsey Moore Date: Thu, 20 Jul 2023 11:29:52 +0200 Subject: rtems: Update references to rtems_task_wake_after rtems_task_wake_after takes a parameter in terms of a count of clock ticks and not a measure in a subunit of seconds. This updates documentation to reflect that. This also makes obvious the caveat about the first tick wait not being a whole tick and points the user at a replacement for better accuracy. Updates #4772 --- cpukit/include/rtems/rtems/tasks.h | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'cpukit/include/rtems/rtems/tasks.h') diff --git a/cpukit/include/rtems/rtems/tasks.h b/cpukit/include/rtems/rtems/tasks.h index 45be8a8730..7465c472f8 100644 --- a/cpukit/include/rtems/rtems/tasks.h +++ b/cpukit/include/rtems/rtems/tasks.h @@ -10,7 +10,7 @@ /* * Copyright (C) 2020, 2021 embedded brains GmbH & Co. KG - * Copyright (C) 1988, 2017 On-Line Applications Research Corporation (OAR) + * Copyright (C) 1988, 2023 On-Line Applications Research Corporation (OAR) * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -1544,15 +1544,16 @@ rtems_status_code rtems_task_mode( /** * @ingroup RTEMSAPIClassicTasks * - * @brief Wakes up after an interval in clock ticks or yields the processor. + * @brief Wakes up after a count of clock ticks have occurred or yields the + * processor. * - * @param ticks is the interval in clock ticks to delay the task or + * @param ticks is the count of clock ticks to delay the task or * #RTEMS_YIELD_PROCESSOR to yield the processor. * - * This directive blocks the calling task for the specified ``ticks`` of clock - * ticks if the value is not equal to #RTEMS_YIELD_PROCESSOR. When the - * requested interval has elapsed, the task is made ready. The clock tick - * directives automatically updates the delay period. The calling task may + * This directive blocks the calling task for the specified ``ticks`` count of + * clock ticks if the value is not equal to #RTEMS_YIELD_PROCESSOR. When the + * requested count of ticks have occurred, the task is made ready. The clock + * tick directives automatically update the delay period. The calling task may * give up the processor and remain in the ready state by specifying a value of * #RTEMS_YIELD_PROCESSOR in ``ticks``. * @@ -1561,7 +1562,11 @@ rtems_status_code rtems_task_mode( * @par Notes * Setting the system date and time with the rtems_clock_set() directive and * similar directives which set CLOCK_REALTIME have no effect on a - * rtems_task_wake_after() blocked task. + * rtems_task_wake_after() blocked task. The delay until first clock tick will + * never be a whole clock tick interval since this directive will never excute + * exactly on a clock tick. Applications requiring use of a clock + * (CLOCK_REALTIME or CLOCK_MONOTONIC) instead of clock ticks should make use + * of clock_nanosleep(). * * @par Constraints * @parblock -- cgit v1.2.3