--- /dev/null
+/* test-local.c
+ *
+ * Sample module for local.h usage.
+ */
+
+
+#include <asm/local.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/timer.h>
+
+static DEFINE_PER_CPU(local_t, counters) = LOCAL_INIT(0);
+
+static struct timer_list test_timer;
+
+/* IPI called on each CPU. */
+static void test_each(void *info)
+{
+ /* Increment the counter from a non preemptible context */
+ printk("Increment on cpu %d\n", smp_processor_id());
+ local_inc(&__get_cpu_var(counters));
+
+ /* This is what incrementing the variable would look like within a
+ * preemptible context (it disables preemption) :
+ *
+ * local_inc(&get_cpu_var(counters));
+ * put_cpu_var(counters);
+ */
+}
+static void do_test_timer(unsigned long data)
+{
+ int cpu;
+
+ /* Increment the counters */
+ on_each_cpu(test_each, NULL, 0, 1);
+ /* Read all the counters */
+ printk("Counters read from CPU %d\n", smp_processor_id());
+ for_each_online_cpu(cpu) {
+ printk("Read : CPU %d, count %ld\n", cpu,
+ local_read(&per_cpu(counters, cpu)));
+ }
+ del_timer(&test_timer);
+ test_timer.expires = jiffies + 1000;
+ add_timer(&test_timer);
+}
+
+static int __init test_init(void)
+{
+ /* initialize the timer that will increment the counter */
+ init_timer(&test_timer);
+ test_timer.function = do_test_timer;
+ test_timer.expires = jiffies + 1;
+ add_timer(&test_timer);
+
+ return 0;
+}
+
+static void __exit test_exit(void)
+{
+ del_timer_sync(&test_timer);
+}
+
+module_init(test_init);
+module_exit(test_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mathieu Desnoyers");
+MODULE_DESCRIPTION("Local Atomic Ops");
+