1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** POSIX wrapper for THREADX */
16 /** */
17 /** */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22 /* Include necessary system files. */
23
24 #include "tx_api.h" /* Threadx API */
25 #include "pthread.h" /* Posix API */
26 #include "px_int.h" /* Posix helper functions */
27
28
29 /**************************************************************************/
30 /* */
31 /* FUNCTION RELEASE */
32 /* */
33 /* pthread_yield PORTABLE C */
34 /* 6.1.7 */
35 /* AUTHOR */
36 /* */
37 /* William E. Lamie, Microsoft Corporation */
38 /* */
39 /* DESCRIPTION */
40 /* */
41 /* This subroutine forces the calling thread to relinquish use of its */
42 /* processor,and to wait in the run queue before it is scheduled again.*/
43 /* If the run queue is empty when this subroutine is called, the */
44 /* calling thread is immediately rescheduled. */
45 /* */
46 /* INPUT */
47 /* */
48 /* Nothing */
49 /* */
50 /* OUTPUT */
51 /* */
52 /* None */
53 /* */
54 /* CALLS */
55 /* */
56 /* posix_internal_error posix internal error function */
57 /* tx_thread_relinquish ThreadX function */
58 /* */
59 /* CALLED BY */
60 /* */
61 /* Application Code */
62 /* */
63 /* RELEASE HISTORY */
64 /* */
65 /* DATE NAME DESCRIPTION */
66 /* */
67 /* 06-02-2021 William E. Lamie Initial Version 6.1.7 */
68 /* */
69 /**************************************************************************/
pthread_yield(VOID)70 VOID pthread_yield(VOID)
71 {
72 /* Make sure we're calling this routine from a thread context. */
73 if (!posix_in_thread_context())
74 {
75 /* return POSIX error. */
76 posix_internal_error(444);
77 }
78
79 /* This relinquishes the CPU. */
80 tx_thread_relinquish();
81 }
82
