git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@2036 35acf78f-673a-0410-8e92-d51de3d6d3f4

os/kernel/include/chbsem.h

@@ -0,0 +1,218 @@
+/*
+    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 <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    chbsem.h
+ * @brief   Binary semaphores structures and macros.
+ *
+ * @addtogroup binary_semaphores
+ * @details Binary semaphores related APIs and services.
+ *
+ *          <h2>Operation mode</h2>
+ *          Binary semaphores are implemented as a set of macros that use the
+ *          existing counting semaphores primitives. The difference between
+ *          counting and binary semaphores is that the counter of binary
+ *          semaphores is not allowed to grow above the value 1. Repeated
+ *          signal operation are ignored. A binary semaphore can thus have
+ *          only two defined states:
+ *          - <b>Taken</b>, when its counter has a value of zero or lower
+ *            than zero. A negative number represent the number of threads
+ *            queued on the binary semaphore.
+ *          - <b>Not taken</b>, when its counter has a value of one.
+ *          .
+ *          Binary semaphores are different from mutexes because there is no
+ *          the concept of ownership, a binary semaphore can be taken by a
+ *          thread and signaled by another thread or an interrupt handler,
+ *          mutexes can only be taken and released by the same thread. Another
+ *          difference is that binary semaphores, unlike mutexes, do not
+ *          implement the priority inheritance protocol.<br>
+ *          In order to use the binary semaphores APIs the @p CH_USE_SEMAPHORES
+ *          option must be enabled in @p chconf.h.
+ * @{
+ */
+
+#ifndef _CHBSEM_H_
+#define _CHBSEM_H_
+
+#if CH_USE_SEMAPHORES
+
+/**
+ * @extends Semaphore
+ *
+ * @brief   Binary semaphore type.
+ */
+typedef struct  {
+  Semaphore             bs_sem;
+} BinarySemaphore;
+
+/**
+ * @brief   Data part of a static semaphore initializer.
+ * @details This macro should be used when statically initializing a semaphore
+ *          that is part of a bigger structure.
+ *
+ * @param[in] name      the name of the semaphore variable
+ * @param[in] n         the counter initial value, this value must be
+ *                      non-negative
+ */
+#define _BSEMAPHORE_DATA(name, t) {_SEMAPHORE_DATA(name.bs_sem), ((t) ? 0 : 1)}
+
+/**
+ * @brief   Static semaphore initializer.
+ * @details Statically initialized semaphores require no explicit
+ *          initialization using @p chSemInit().
+ *
+ * @param[in] name      the name of the semaphore variable
+ * @param[in] n         the counter initial value, this value must be
+ *                      non-negative
+ */
+#define BSEMAPHORE_DECL(name, t) Semaphore name = _BSEMAPHORE_DATA(name, t)
+
+
+/**
+ * @brief   Initializes a binary semaphore.
+ *
+ * @param[out] bsp      pointer to a @p BinarySemaphore structure
+ * @param[in] taken     initial state of the binary semaphore:
+ *                      - @a FALSE, the initial state is not taken.
+ *                      - @a TRUE, the initial state is taken.
+ *                      .
+ */
+#define chBSemInit(bsp, taken) chSemInit(&bsp->bs_sem, taken ? 0 : 1)
+
+/**
+ * @brief   Wait operation on the binary semaphore.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @retval RDY_OK       if the binary semaphore had been successfully taken.
+ * @retval RDY_RESET    if the binary semaphore has been reset using
+ *                      @p bsemReset().
+ */
+#define chBSemWait(bsp) chSemWait(&bsp->bs_sem)
+
+/**
+ * @brief   Wait operation on the binary semaphore.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @retval RDY_OK       if the binary semaphore had been successfully taken.
+ * @retval RDY_RESET    if the binary semaphore has been reset using
+ *                      @p bsemReset().
+ */
+#define chBSemWaitS(bsp) chSemWaitS(&bsp->bs_sem)
+
+/**
+ * @brief   Wait operation on the binary semaphore.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @param[in] time      the number of ticks before the operation timeouts,
+ *                      the following special values are allowed:
+ *                      - @a TIME_IMMEDIATE immediate timeout.
+ *                      - @a TIME_INFINITE no timeout.
+ *                      .
+ * @retval RDY_OK       if the binary semaphore had been successfully taken.
+ * @retval RDY_RESET    if the binary semaphore has been reset using
+ *                      @p bsemReset().
+ * @retval RDY_TIMEOUT  if the binary semaphore was not signaled or reset
+ *                      within the specified timeout.
+ */
+#define chBSemWaitTimeout(bsp, time) chSemWaitTimeout(&bsp->bs_sem, time)
+
+/**
+ * @brief   Wait operation on the binary semaphore.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @param[in] time      the number of ticks before the operation timeouts,
+ *                      the following special values are allowed:
+ *                      - @a TIME_IMMEDIATE immediate timeout.
+ *                      - @a TIME_INFINITE no timeout.
+ *                      .
+ * @retval RDY_OK       if the binary semaphore had been successfully taken.
+ * @retval RDY_RESET    if the binary semaphore has been reset using
+ *                      @p bsemReset().
+ * @retval RDY_TIMEOUT  if the binary semaphore was not signaled or reset
+ *                      within the specified timeout.
+ */
+#define chBSemWaitTimeoutS(bsp, time) chSemWaitTimeoutS(&bsp->bs_sem, time)
+
+/**
+ * @brief   Reset operation on the binary semaphore.
+ * @note    The released threads can recognize they were waked up by a reset
+ *          rather than a signal because the @p bsemWait() will return
+ *          @p RDY_RESET instead of @p RDY_OK.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @param[in] taken     new state of the binary semaphore
+ *                      - @a FALSE, the new state is not taken.
+ *                      - @a TRUE, the new state is taken.
+ *                      .
+ */
+#define chBSemReset(bsp, taken) chSemReset(&bsp->bs_sem, taken ? 0 : 1)
+
+/**
+ * @brief   Reset operation on the binary semaphore.
+ * @note    The released threads can recognize they were waked up by a reset
+ *          rather than a signal because the @p bsemWait() will return
+ *          @p RDY_RESET instead of @p RDY_OK.
+ * @note    This function does not reschedule.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @param[in] taken     new state of the binary semaphore
+ *                      - @a FALSE, the new state is not taken.
+ *                      - @a TRUE, the new state is taken.
+ *                      .
+ */
+#define chBSemResetI(bsp, taken) chSemResetI(&bsp->bs_sem, taken ? 0 : 1)
+
+/**
+ * @brief   Performs a signal operation on a binary semaphore.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ */
+#define chBSemSignal(bsp) {                                                 \
+  chSysLock();                                                              \
+  chBSemSignalI(bsp);                                                       \
+  chSchRescheduleS();                                                       \
+  chSysUnlock();                                                            \
+}
+
+/**
+ * @brief   Performs a signal operation on a binary semaphore.
+ * @note    This function does not reschedule.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ */
+#define chBSemSignalI(bsp) {                                                \
+  if (bsp->bs_sem.s_cnt < 1)                                                \
+    chSemSignalI(&bsp->bs_sem);                                             \
+}
+
+/**
+ * @brief   Returns the binary semaphore current state.
+ *
+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @return              The binary semaphore current state.
+ * @retval FALSE        if the binary semaphore is not taken.
+ * @retval TRUE         if the binary semaphore is taken.
+ */
+#define chBSemGetStateI(bsp) ((bsp)->bs_sem.s_cnt > 0 ? 0 : 1)
+
+#endif /* CH_USE_SEMAPHORES */
+
+#endif /* _CHBSEM_H_ */
+
+/** @} */

os/kernel/kernel.dox

@@ -72,7 +72,12 @@
  */
 
 /**
- * @defgroup semaphores Semaphores
+ * @defgroup semaphores Counting Semaphores
+ * @ingroup synchronization
+ */
+
+/**
+ * @defgroup binary_semaphores Binary Semaphores
  * @ingroup synchronization
  */
 

os/kernel/src/chcond.c

@@ -17,8 +17,7 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 /*
-   Concepts and parts of this file are contributed by and Copyright (C) 2008
+   Concepts and parts of this file have been contributed by Leon Woestenberg.
-   of Leon Woestenberg.
  */
 
 /**

os/kernel/src/chqueues.c

@@ -126,6 +126,10 @@ msg_t chIQGetTimeout(InputQueue *iqp, systime_t time) {
   msg_t msg;
 
   chSysLock();
+  
+  if (iqp->q_notify)
+    iqp->q_notify();
+
   if ((msg = chSemWaitTimeoutS(&iqp->q_sem, time)) < RDY_OK) {
     chSysUnlock();
     return msg;
@@ -134,9 +138,6 @@ msg_t chIQGetTimeout(InputQueue *iqp, systime_t time) {
   if (iqp->q_rdptr >= iqp->q_top)
     iqp->q_rdptr = iqp->q_buffer;
 
-  if (iqp->q_notify)
-    iqp->q_notify();
-
   chSysUnlock();
   return b;
 }

os/ports/GCC/ARMCMx/chcore_v7m.c

@@ -27,6 +27,7 @@
 
 #include "ch.h"
 
+#if !defined(CH_CURRP_REGISTER_CACHE) || defined(__DOXXYGEN__)
 /**
  * @brief   Internal context stacking.
  */
@@ -40,6 +41,15 @@
 #define POP_CONTEXT() {                                                     \
   asm volatile ("pop     {r4, r5, r6, r7, r8, r9, r10, r11, pc}");          \
 }
+#else /* defined(CH_CURRP_REGISTER_CACHE) */
+#define PUSH_CONTEXT() {                                                    \
+  asm volatile ("push    {r4, r5, r6, r8, r9, r10, r11, lr}");              \
+}
+
+#define POP_CONTEXT() {                                                     \
+  asm volatile ("pop     {r4, r5, r6, r8, r9, r10, r11, pc}");              \
+}
+#endif /* defined(CH_CURRP_REGISTER_CACHE) */
 
 #if !CH_OPTIMIZE_SPEED
 void _port_lock(void) {

readme.txt

@@ -59,6 +59,10 @@
 *****************************************************************************
 
 *** 2.1.0 ***
+- FIX: Fixed notification order in input queues (bug 3020708)(backported in
+  2.0.1).
+- FIX: Fixed non functional CH_CURRP_REGISTER_CACHE option in the Cortex-M3
+  port (bug 3020702)(backported in 2.0.1).
 - FIX: Fixed non functional CH_DBG_ENABLE_STACK_CHECK option in the Cortex-M3
   caused by GCC 4.5.0, the fix also improves the context switch performance
   because GCC 4.5.0 apparently was generating useless instructions within the
@@ -73,6 +77,9 @@
 - FIX: Fixed assertion in adcStop() (bug 3015109)(backported in 2.0.0).
 - NEW: Added timers clock macros to the STM32 clock tree HAL driver (backported
   in 2.0.1).
+- NEW: Added Binary Semaphores among the synchronization primitives. The new
+  subsystem is entirely implemented as macros over the existing and proven
+  Counting Semaphores thus takes no space.
 - OPT: Simplified the test suite code, now it is smaller.
 - Reorganized the documentation, now the description of the device drivers
   implementation is under the HAL module instead of the Ports module.