samples/trace_printk/trace-printk.c

   1 #include <linux/module.h>
   2 #include <linux/kthread.h>
   3 #include <linux/irq_work.h>
   4
   5 /* Must not be static to force gcc to consider these non constant */
   6 char *trace_printk_test_global_str =
   7         "This is a dynamic string that will use trace_puts\n";
   8
   9 char *trace_printk_test_global_str_irq =
  10         "(irq) This is a dynamic string that will use trace_puts\n";
  11
  12 char *trace_printk_test_global_str_fmt =
  13         "%sThis is a %s that will use trace_printk\n";
  14
  15 static struct irq_work irqwork;
  16
  17 static void trace_printk_irq_work(struct irq_work *work)
  18 {
  19         trace_printk("(irq) This is a static string that will use trace_bputs\n");
  20         trace_printk(trace_printk_test_global_str_irq);
  21
  22         trace_printk("(irq) This is a %s that will use trace_bprintk()\n",
  23                      "static string");
  24
  25         trace_printk(trace_printk_test_global_str_fmt,
  26                      "(irq) ", "dynamic string");
  27 }
  28
  29 static int __init trace_printk_init(void)
  30 {
  31         init_irq_work(&irqwork, trace_printk_irq_work);
  32
  33         trace_printk("This is a static string that will use trace_bputs\n");
  34         trace_printk(trace_printk_test_global_str);
  35
  36         /* Kick off printing in irq context */
  37         irq_work_queue(&irqwork);
  38
  39         trace_printk("This is a %s that will use trace_bprintk()\n",
  40                      "static string");
  41
  42         trace_printk(trace_printk_test_global_str_fmt, "", "dynamic string");
  43
  44         return 0;
  45 }
  46
  47 static void __exit trace_printk_exit(void)
  48 {
  49 }
  50
  51 module_init(trace_printk_init);
  52 module_exit(trace_printk_exit);
  53
  54 MODULE_AUTHOR("Steven Rostedt");
  55 MODULE_DESCRIPTION("trace-printk");
  56 MODULE_LICENSE("GPL");