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 /** Thread */ 19 /** */ 20 /**************************************************************************/ 21 /**************************************************************************/ 22 23 24 #define TX_SOURCE_CODE 25 26 27 /* Include necessary system files. */ 28 29 #include "tx_api.h" 30 #include "tx_thread.h" 31 #include "tx_timer.h" 32 33 34 /**************************************************************************/ 35 /* */ 36 /* FUNCTION RELEASE */ 37 /* */ 38 /* _tx_thread_context_save Linux/GNU */ 39 /* 6.1 */ 40 /* AUTHOR */ 41 /* */ 42 /* William E. Lamie, Microsoft Corporation */ 43 /* */ 44 /* DESCRIPTION */ 45 /* */ 46 /* This function saves the context of an executing thread in the */ 47 /* beginning of interrupt processing. The function also ensures that */ 48 /* the system stack is used upon return to the calling ISR. */ 49 /* */ 50 /* INPUT */ 51 /* */ 52 /* None */ 53 /* */ 54 /* OUTPUT */ 55 /* */ 56 /* None */ 57 /* */ 58 /* CALLS */ 59 /* */ 60 /* _tx_linux_debug_entry_insert */ 61 /* tx_linux_mutex_lock */ 62 /* _tx_linux_thread_suspend */ 63 /* tx_linux_mutex_unlock */ 64 /* */ 65 /* CALLED BY */ 66 /* */ 67 /* ISRs */ 68 /* */ 69 /* RELEASE HISTORY */ 70 /* */ 71 /* DATE NAME DESCRIPTION */ 72 /* */ 73 /* 09-30-2020 William E. Lamie Initial Version 6.1 */ 74 /* */ 75 /**************************************************************************/ _tx_thread_context_save(VOID)76VOID _tx_thread_context_save(VOID) 77 { 78 79 /* Debug entry. */ 80 _tx_linux_debug_entry_insert("CONTEXT_SAVE", __FILE__, __LINE__); 81 82 /* Lock mutex to ensure other threads are not playing with 83 the core ThreadX data structures. */ 84 tx_linux_mutex_lock(_tx_linux_mutex); 85 86 /* If an application thread is running, suspend it to simulate preemption. */ 87 if ((_tx_thread_current_ptr) && (_tx_thread_system_state == 0)) 88 { 89 90 /* Debug entry. */ 91 _tx_linux_debug_entry_insert("CONTEXT_SAVE-suspend_thread", __FILE__, __LINE__); 92 93 /* Yes, this is the first interrupt and an application thread is running... 94 suspend it! */ 95 _tx_linux_thread_suspend(_tx_thread_current_ptr -> tx_thread_linux_thread_id); 96 97 /* Indicate that this thread was suspended asynchronously. */ 98 _tx_thread_current_ptr -> tx_thread_linux_suspension_type = 1; 99 } 100 101 /* Increment the nested interrupt condition. */ 102 _tx_thread_system_state++; 103 104 /* Unlock linux mutex. */ 105 tx_linux_mutex_unlock(_tx_linux_mutex); 106 } 107 108
