Event management routines. More...

#include <cfg/os.h>
#include <compiler.h>
#include <sys/atom.h>
#include <sys/heap.h>
#include <sys/timer.h>
#include <sys/thread.h>
#include <sys/event.h>
#include <sys/nutdebug.h>
#include <sys/osdebug.h>
#include <stdio.h>

Include dependency graph for event.c:

Go to the source code of this file.

Functions
void	NutEventTimeout (HANDLE timer, void *arg)
	Timer callback in case of event timeout.
int	NutEventWait (volatile HANDLE *qhp, uint32_t ms)
	Wait for an event in a specified queue.
int	NutEventWaitNext (volatile HANDLE *qhp, uint32_t ms)
	Wait for a new event in a specified queue.
int	NutEventPostAsync (volatile HANDLE *qhp)
	Asynchronously post an event to a specified queue.
int	NutEventPost (volatile HANDLE *qhp)
	Post an event to a specified queue.
int	NutEventBroadcastAsync (volatile HANDLE *qhp)
	Asynchronously broadcast an event to a specified queue.
int	NutEventBroadcast (volatile HANDLE *qhp)
	Broadcast an event to a specified queue.

Detailed Description

Event management routines.

This kernel module provides thread synchronization.

*
* $Log$
* Revision 1.26 2009/01/17 15:37:52 haraldkipp
* Added some NUTASSERT macros to check function parameters.
*
* Revision 1.25 2008/08/11 07:00:33 haraldkipp
* BSD types replaced by stdint types (feature request #1282721).
*
* Revision 1.24 2006/06/28 14:38:34 haraldkipp
* Event and timer handling re-design, again. This fixes a bug, which
* possibly existed since version 3.9.8 and freezes threads under heavy
* load. After several people reported this problem, Michael Jones and
* Henrik Maier finally detected the cause and came up with a solution.
* However, this fix let interrupt latency times depend on the number
* of running threads again and a new solution was implemented, which
* not only avoids this problem but further decreases interrupt latencies
* by adding an event post counter to the THREADINFO structure. This
* counter frees the interrupt routines from dealing with linked lists
* and frees the kernel from dealing with linked lists concurrently
* modified by interrupts. Furthermore, timeout timers are now released
* early. Michael Jones reported, that previous versions suffer from low
* memory situations while processing many events within short periods.
* The timer list is now double linked to reduce removal time. Internally
* timeout condition is now flagged by setting the timer handle to
* SIGNALED.
* Unfortunately new bugs were introduced with this re-design. Special
* thanks to Michael Jones, who located the "exact spot of the crime" and
* proofed, that his final fixes let Nut/OS behave quite well under heavy
* traffic storms. This new version will probably help also, if you
* experienced long term instability.
* LGPL copyright removed after all the initial sources had been finally
* replaced by BSDL'ed code.
* Last not least the documentation had been updated.
*
* Revision 1.23 2005/08/18 15:33:54 christianwelzel
* Fixed bug in handling of NUTDEBUG.
*
* Revision 1.22 2005/07/21 14:23:17 freckle
* inlined NutEventPostFromIrq call in NutEventPostAsync to reduce CS
*
* Revision 1.21 2005/07/20 09:19:45 haraldkipp
* Use native heap calls to avoid dependencies
*
* Revision 1.20 2005/07/13 15:25:50 freckle
* Rewrote NutEventWait to get short critical sections
*
* Revision 1.19 2005/07/12 18:44:05 freckle
* Removed unnecessary critical sections in NutEventPost, NutEventWait
*
* Revision 1.18 2005/07/12 18:04:12 freckle
* Reverted NutEventWait back to 1.15 but kept critical section in
* NutEventTimeout + changed CS in NutEventWaitNext
*
* Revision 1.15 2005/06/10 12:59:26 freckle
* corrected NuEventBroadcastAsync documentation.
* NutEventBroadcast uses NutEventPostAsync which disables IRQsCVS:
* ----------------------------------------------------------------------
*
* Revision 1.14 2005/02/21 12:37:57 phblum
* Removed tabs and added semicolons after NUTTRACER macros
*
* Revision 1.13 2005/02/17 14:45:10 phblum
* In NutEventWait(), replaced NutThreadRemoveQueue by direct removal of first thread in queue.
*
* Revision 1.12 2005/02/16 19:53:17 haraldkipp
* Ready-to-run queue handling removed from interrupt context.
*
* Revision 1.11 2005/01/24 22:34:35 freckle
* Added new tracer by Phlipp Blum <blum@tik.ee.ethz.ch>
*
* Revision 1.10 2005/01/24 21:11:21 freckle
* renamed NutEventPostFromIRQ into NutEventPostFromIrq
*
* Revision 1.9 2005/01/21 16:49:44 freckle
* Seperated calls to NutEventPostAsync between Threads and IRQs
*
* Revision 1.8 2005/01/19 17:59:45 freckle
* Improved interrupt performance by reducing some critical section
*
* Revision 1.7 2005/01/02 10:07:10 haraldkipp
* Replaced platform dependant formats in debug outputs.
*
* Revision 1.6 2004/07/20 08:33:28 freckle
* Fixed NutPostEvent to give up CPU if there is another thread ready with
* same priority to match the documentation
* Also removed 'SWP..' NBUTDEBUG output, as switching is done calling NutThreadYield()
*
* Revision 1.5 2004/04/07 12:13:58 haraldkipp
* Matthias Ringwald's *nix emulation added
*
* Revision 1.4 2004/03/19 09:05:12 jdubiec
* Fixed format strings declarations for AVR.
*
* Revision 1.3 2004/03/16 16:48:45 haraldkipp
* Added Jan Dubiec's H8/300 port.
*
* Revision 1.2 2003/07/20 18:27:44 haraldkipp
* Explain how to disable timeout.
*
* Revision 1.1.1.1 2003/05/09 14:41:49 haraldkipp
* Initial using 3.2.1
*
* Revision 1.20 2003/04/21 17:07:41 harald
* Comments added
*
* Revision 1.19 2003/03/31 14:46:41 harald
* Broadcasts clear signaled queues
*
* Revision 1.18 2003/02/04 18:15:56 harald
* Version 3 released
*
* Revision 1.17 2003/01/14 16:56:39 harald
* Racing condition on signaled events fixed.
* All posting routines return the number of woken up threads.
*
* Revision 1.16 2002/06/26 17:29:44 harald
* First pre-release with 2.4 stack
*
*

Definition in file event.c.

Functions

Detailed Description