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-rw-r--r--lib/pcounter.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/pcounter.c b/lib/pcounter.c
new file mode 100644
index 00000000000..9b56807da93
--- /dev/null
+++ b/lib/pcounter.c
@@ -0,0 +1,58 @@
+/*
+ * Define default pcounter functions
+ * Note that often used pcounters use dedicated functions to get a speed increase.
+ * (see DEFINE_PCOUNTER/REF_PCOUNTER_MEMBER)
+ */
+
+#include <linux/module.h>
+#include <linux/pcounter.h>
+#include <linux/smp.h>
+#include <linux/cpumask.h>
+
+static void pcounter_dyn_add(struct pcounter *self, int inc)
+{
+ per_cpu_ptr(self->per_cpu_values, smp_processor_id())[0] += inc;
+}
+
+static int pcounter_dyn_getval(const struct pcounter *self, int cpu)
+{
+ return per_cpu_ptr(self->per_cpu_values, cpu)[0];
+}
+
+int pcounter_getval(const struct pcounter *self)
+{
+ int res = 0, cpu;
+
+ for_each_possible_cpu(cpu)
+ res += self->getval(self, cpu);
+
+ return res;
+}
+EXPORT_SYMBOL_GPL(pcounter_getval);
+
+int pcounter_alloc(struct pcounter *self)
+{
+ int rc = 0;
+ if (self->add == NULL) {
+ self->per_cpu_values = alloc_percpu(int);
+ if (self->per_cpu_values != NULL) {
+ self->add = pcounter_dyn_add;
+ self->getval = pcounter_dyn_getval;
+ } else
+ rc = 1;
+ }
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pcounter_alloc);
+
+void pcounter_free(struct pcounter *self)
+{
+ if (self->per_cpu_values != NULL) {
+ free_percpu(self->per_cpu_values);
+ self->per_cpu_values = NULL;
+ self->getval = NULL;
+ self->add = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(pcounter_free);
+