faf3aa7c22
It is vital to denote the file name and summary for each source, otherwise readers could not figure out the corresponding files.
77 lines
1.7 KiB
C
77 lines
1.7 KiB
C
/*
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* completions.c
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*/
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#include <linux/completion.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/kthread.h>
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#include <linux/module.h>
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static struct {
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struct completion crank_comp;
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struct completion flywheel_comp;
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} machine;
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static int machine_crank_thread(void *arg)
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{
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pr_info("Turn the crank\n");
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complete_all(&machine.crank_comp);
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complete_and_exit(&machine.crank_comp, 0);
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}
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static int machine_flywheel_spinup_thread(void *arg)
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{
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wait_for_completion(&machine.crank_comp);
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pr_info("Flywheel spins up\n");
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complete_all(&machine.flywheel_comp);
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complete_and_exit(&machine.flywheel_comp, 0);
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}
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static int completions_init(void)
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{
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struct task_struct *crank_thread;
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struct task_struct *flywheel_thread;
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pr_info("completions example\n");
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init_completion(&machine.crank_comp);
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init_completion(&machine.flywheel_comp);
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crank_thread = kthread_create(machine_crank_thread, NULL, "KThread Crank");
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if (IS_ERR(crank_thread))
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goto ERROR_THREAD_1;
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flywheel_thread = kthread_create(machine_flywheel_spinup_thread, NULL,
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"KThread Flywheel");
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if (IS_ERR(flywheel_thread))
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goto ERROR_THREAD_2;
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wake_up_process(flywheel_thread);
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wake_up_process(crank_thread);
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return 0;
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ERROR_THREAD_2:
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kthread_stop(crank_thread);
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ERROR_THREAD_1:
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return -1;
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}
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void completions_exit(void)
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{
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wait_for_completion(&machine.crank_comp);
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wait_for_completion(&machine.flywheel_comp);
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pr_info("completions exit\n");
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}
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module_init(completions_init);
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module_exit(completions_exit);
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MODULE_DESCRIPTION("Completions example");
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MODULE_LICENSE("GPL");
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