42 lines
777 B
C
42 lines
777 B
C
/*
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* example_mutex.c
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*/
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/mutex.h>
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DEFINE_MUTEX(mymutex);
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static int example_mutex_init(void)
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{
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int ret;
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pr_info("example_mutex init\n");
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ret = mutex_trylock(&mymutex);
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if (ret != 0) {
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pr_info("mutex is locked\n");
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if (mutex_is_locked(&mymutex) == 0)
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pr_info("The mutex failed to lock!\n");
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mutex_unlock(&mymutex);
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pr_info("mutex is unlocked\n");
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} else
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pr_info("Failed to lock\n");
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return 0;
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}
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static void example_mutex_exit(void)
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{
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pr_info("example_mutex exit\n");
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}
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module_init(example_mutex_init);
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module_exit(example_mutex_exit);
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MODULE_DESCRIPTION("Mutex example");
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MODULE_LICENSE("GPL");
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