From f1bb1a01ca40b8c999346c701450fcf0ca74827a Mon Sep 17 00:00:00 2001 From: gdisirio Date: Fri, 12 Mar 2010 11:25:52 +0000 Subject: git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@1738 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- docs/src/articles.dox | 1 + docs/src/roundrobin.dox | 50 +++++++++++++++++++++++++++++++++++++++++++++++ os/ports/RC/STM8/port.dox | 12 ++++++------ readme.txt | 1 + 4 files changed, 58 insertions(+), 6 deletions(-) create mode 100644 docs/src/roundrobin.dox diff --git a/docs/src/articles.dox b/docs/src/articles.dox index f8a40e2f7..ea471bdb7 100644 --- a/docs/src/articles.dox +++ b/docs/src/articles.dox @@ -25,6 +25,7 @@ * - @subpage article_wakeup * - @subpage article_manage_memory * - @subpage article_stacks + * - @subpage article_roundrobin * - @subpage article_lifecycle * - @subpage article_mutual_exclusion * - @subpage article_atomic diff --git a/docs/src/roundrobin.dox b/docs/src/roundrobin.dox new file mode 100644 index 000000000..8158a5c03 --- /dev/null +++ b/docs/src/roundrobin.dox @@ -0,0 +1,50 @@ +/* + ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio. + + This file is part of ChibiOS/RT. + + ChibiOS/RT is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + ChibiOS/RT is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +/** + * @page article_roundrobin Round Robin scheduling explained + * Unlike many other RTOSes, ChibiOS/RT supports multiple threads at the + * same priority level and schedules them using an aggressive + * round-robin strategy.
+ * The strategy is defined as aggressive because any scheduling event + * can cause the round-robin threads to rotate.
+ * A round-robin rotation can happen because of the following events: + * - The currently executed thread voluntarily invokes the @p chThdYield() + * API in order to allow the execution of another thread at the same + * priority level, if any. + * - The currently executed thread voluntarily goes into a sleep state + * (see @ref thread_states), when the thread is waken it goes behind + * all the other threads at the same priority level. + * - The currently executed thread is preempted by an higher priority + * thread, the thread is reinserted in the ready list (see @ref scheduling) + * behind all the other threads at the same priority level. + * - If the @p CH_TIME_QUANTUM configuration constant is set to a value + * greater than zero and if the specified time quantum expired and if + * a thread with equal priority is ready then the currently executing + * thread is automatically reinserted in the ready list behind all the + * other threads at the same priority level. + * . + * As you can see the @p CH_TIME_QUANTUM setting is really useful only if + * there are threads at the same priority level that can run not preempted + * for long periods of time and that do not explicitly yield using + * @p chThdYield(). Because of this you should consider to set + * @p CH_TIME_QUANTUM to zero in your configuration file, this makes the + * kernel much faster and smaller and does not forbid the use of + * multiple threads at the same priority level. + */ diff --git a/os/ports/RC/STM8/port.dox b/os/ports/RC/STM8/port.dox index 332b7f3f1..3c2e812a8 100644 --- a/os/ports/RC/STM8/port.dox +++ b/os/ports/RC/STM8/port.dox @@ -77,11 +77,11 @@ */ /** - * @defgroup MSP430_CORE Core Port Implementation - * @brief MSP430 specific port code, structures and macros. + * @defgroup STM8_CORE Core Port Implementation + * @brief STM8 specific port code, structures and macros. * - * @ingroup MSP430 - * @file MSP430/chtypes.h Port types. - * @file MSP430/chcore.h Port related structures and macros. - * @file MSP430/chcore.c Port related code. + * @ingroup STM8 + * @file STM8/chtypes.h Port types. + * @file STM8/chcore.h Port related structures and macros. + * @file STM8/chcore.c Port related code. */ diff --git a/readme.txt b/readme.txt index 906546e8a..10bc6e999 100644 --- a/readme.txt +++ b/readme.txt @@ -64,6 +64,7 @@ - NEW: Added RIDE7 project files to the STM32 demo under a ./ride7 subdirectory, this should make things easier for RIDE7 users. The normal makefile is still available of course. +- NEW: New article in the documentation. Fixed an orphaned page (STM8 port). *** 1.5.3 *** - FIX: Removed C99-style variables declarations (bug 2964418)(backported -- cgit v1.2.3