1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** ThreadX Component */
17 /** */
18 /** Mutex */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23 #define TX_SOURCE_CODE
24
25
26 /* Include necessary system files. */
27
28 #include "tx_api.h"
29 #include "tx_thread.h"
30 #include "tx_trace.h"
31 #include "tx_mutex.h"
32
33
34 /**************************************************************************/
35 /* */
36 /* FUNCTION RELEASE */
37 /* */
38 /* _tx_mutex_create PORTABLE C */
39 /* 6.1 */
40 /* AUTHOR */
41 /* */
42 /* William E. Lamie, Microsoft Corporation */
43 /* */
44 /* DESCRIPTION */
45 /* */
46 /* This function creates a mutex with optional priority inheritance as */
47 /* specified in this call. */
48 /* */
49 /* INPUT */
50 /* */
51 /* mutex_ptr Pointer to mutex control block*/
52 /* name_ptr Pointer to mutex name */
53 /* inherit Priority inheritance option */
54 /* */
55 /* OUTPUT */
56 /* */
57 /* TX_SUCCESS Successful completion status */
58 /* */
59 /* CALLS */
60 /* */
61 /* None */
62 /* */
63 /* CALLED BY */
64 /* */
65 /* Application Code */
66 /* */
67 /* RELEASE HISTORY */
68 /* */
69 /* DATE NAME DESCRIPTION */
70 /* */
71 /* 05-19-2020 William E. Lamie Initial Version 6.0 */
72 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
73 /* resulting in version 6.1 */
74 /* */
75 /**************************************************************************/
_tx_mutex_create(TX_MUTEX * mutex_ptr,CHAR * name_ptr,UINT inherit)76 UINT _tx_mutex_create(TX_MUTEX *mutex_ptr, CHAR *name_ptr, UINT inherit)
77 {
78
79 TX_INTERRUPT_SAVE_AREA
80
81 TX_MUTEX *next_mutex;
82 TX_MUTEX *previous_mutex;
83
84
85 /* Initialize mutex control block to all zeros. */
86 TX_MEMSET(mutex_ptr, 0, (sizeof(TX_MUTEX)));
87
88 /* Setup the basic mutex fields. */
89 mutex_ptr -> tx_mutex_name = name_ptr;
90 mutex_ptr -> tx_mutex_inherit = inherit;
91
92 /* Disable interrupts to place the mutex on the created list. */
93 TX_DISABLE
94
95 /* Setup the mutex ID to make it valid. */
96 mutex_ptr -> tx_mutex_id = TX_MUTEX_ID;
97
98 /* Setup the thread mutex release function pointer. */
99 _tx_thread_mutex_release = &(_tx_mutex_thread_release);
100
101 /* Place the mutex on the list of created mutexes. First,
102 check for an empty list. */
103 if (_tx_mutex_created_count == TX_EMPTY)
104 {
105
106 /* The created mutex list is empty. Add mutex to empty list. */
107 _tx_mutex_created_ptr = mutex_ptr;
108 mutex_ptr -> tx_mutex_created_next = mutex_ptr;
109 mutex_ptr -> tx_mutex_created_previous = mutex_ptr;
110 }
111 else
112 {
113
114 /* This list is not NULL, add to the end of the list. */
115 next_mutex = _tx_mutex_created_ptr;
116 previous_mutex = next_mutex -> tx_mutex_created_previous;
117
118 /* Place the new mutex in the list. */
119 next_mutex -> tx_mutex_created_previous = mutex_ptr;
120 previous_mutex -> tx_mutex_created_next = mutex_ptr;
121
122 /* Setup this mutex's next and previous created links. */
123 mutex_ptr -> tx_mutex_created_previous = previous_mutex;
124 mutex_ptr -> tx_mutex_created_next = next_mutex;
125 }
126
127 /* Increment the ownership count. */
128 _tx_mutex_created_count++;
129
130 /* Optional mutex create extended processing. */
131 TX_MUTEX_CREATE_EXTENSION(mutex_ptr)
132
133 /* If trace is enabled, register this object. */
134 TX_TRACE_OBJECT_REGISTER(TX_TRACE_OBJECT_TYPE_MUTEX, mutex_ptr, name_ptr, inherit, 0)
135
136 /* If trace is enabled, insert this event into the trace buffer. */
137 TX_TRACE_IN_LINE_INSERT(TX_TRACE_MUTEX_CREATE, mutex_ptr, inherit, TX_POINTER_TO_ULONG_CONVERT(&next_mutex), 0, TX_TRACE_MUTEX_EVENTS)
138
139 /* Log this kernel call. */
140 TX_EL_MUTEX_CREATE_INSERT
141
142 /* Restore interrupts. */
143 TX_RESTORE
144
145 /* Return TX_SUCCESS. */
146 return(TX_SUCCESS);
147 }
148
149
