Deepika Bhavnani
/
mbed-os-example-criticalsection
Example to demonstrate race condition and how CriticalSectionLock API helps in resolving that.
main.cpp
- Committer:
- deepikabhavnani
- Date:
- 2017-10-20
- Revision:
- 0:36e8acd8e607
File content as of revision 0:36e8acd8e607:
/* * Copyright (c) 2016-2016, ARM Limited, All Rights Reserved * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "rtos/Thread.h" #include "mbed.h" #include "rtos/rtos_idle.h" #include "platform/mbed_critical.h" #define USE_CRITICAL_SECTION_LOCK 1 // Set 0 to see race condition // Note: Might require few runs to see race condition #define THREAD_CNT 8 int32_t value = 100000; volatile int32_t count = 0; void increment(void) { for (int i = 0; i < value; i++) { #if (USE_CRITICAL_SECTION_LOCK == 1) CriticalSectionLock lock; #endif count += 1; } } int get_count(void) { if (count == (value * THREAD_CNT)) { printf("No Race condition\n"); } else { printf("Race condition\n"); } return count; } int main() { Thread counter_thread[THREAD_CNT]; for (int i = 0; i < THREAD_CNT; i++) { counter_thread[i].start(callback(increment)); } // Wait for the threads to finish for (int i = 0; i < THREAD_CNT; i++) { counter_thread[i].join(); } printf ("Counter = %d\n", get_count()); }