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Kernel v2.6.25-rc7 /lib/pcounter.c

Filename:/lib/pcounter.c
Lines Added:58
Lines Deleted:0
Also changed in: (Previous) 2.6.25-rc6  2.6.25-rc5  2.6.25-rc4  2.6.25-rc3  2.6.25-rc2  2.6.25-rc1 
(Following) 2.6.25-rc8  2.6.25-rc9  2.6.25  2.6.25-git2  2.6.25-git3  2.6.25-git4 

Location
[  2.6.25-rc7
  [  lib
     o  pcounter.c

Patch

diff --git a/lib/pcounter.c b/lib/pcounter.c
new file mode 100644
index 0000000..9b56807
--- /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);
+


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