diff options
Diffstat (limited to 'lib/pcounter.c')
-rw-r--r-- | lib/pcounter.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/pcounter.c b/lib/pcounter.c new file mode 100644 index 000000000000..9b56807da93b --- /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); + |