b8bbcd8a07
The kernel.h should be discouraged for use. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
63 lines
1.4 KiB
C
63 lines
1.4 KiB
C
/*
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* example_spinlock.c
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*/
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/printk.h>
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#include <linux/spinlock.h>
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static DEFINE_SPINLOCK(sl_static);
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static spinlock_t sl_dynamic;
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static void example_spinlock_static(void)
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{
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unsigned long flags;
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spin_lock_irqsave(&sl_static, flags);
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pr_info("Locked static spinlock\n");
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/* Do something or other safely. Because this uses 100% CPU time, this
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* code should take no more than a few milliseconds to run.
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*/
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spin_unlock_irqrestore(&sl_static, flags);
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pr_info("Unlocked static spinlock\n");
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}
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static void example_spinlock_dynamic(void)
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{
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unsigned long flags;
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spin_lock_init(&sl_dynamic);
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spin_lock_irqsave(&sl_dynamic, flags);
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pr_info("Locked dynamic spinlock\n");
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/* Do something or other safely. Because this uses 100% CPU time, this
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* code should take no more than a few milliseconds to run.
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*/
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spin_unlock_irqrestore(&sl_dynamic, flags);
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pr_info("Unlocked dynamic spinlock\n");
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}
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static int example_spinlock_init(void)
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{
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pr_info("example spinlock started\n");
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example_spinlock_static();
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example_spinlock_dynamic();
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return 0;
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}
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static void example_spinlock_exit(void)
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{
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pr_info("example spinlock exit\n");
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}
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module_init(example_spinlock_init);
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module_exit(example_spinlock_exit);
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MODULE_DESCRIPTION("Spinlock example");
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MODULE_LICENSE("GPL");
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