blob: b7a2fb12287332eb01d7fe48cf0f0ad5eb7902dc [file] [log] [blame]
#include "fio.h"
#include "mutex.h"
#include "smalloc.h"
#include "flist.h"
struct fio_flow {
unsigned int refs;
struct flist_head list;
unsigned int id;
long long int flow_counter;
};
static struct flist_head *flow_list;
static struct fio_mutex *flow_lock;
int flow_threshold_exceeded(struct thread_data *td)
{
struct fio_flow *flow = td->flow;
int sign;
if (!flow)
return 0;
sign = td->o.flow > 0 ? 1 : -1;
if (sign * flow->flow_counter > td->o.flow_watermark) {
if (td->o.flow_sleep)
usleep(td->o.flow_sleep);
return 1;
}
/* No synchronization needed because it doesn't
* matter if the flow count is slightly inaccurate */
flow->flow_counter += td->o.flow;
return 0;
}
static struct fio_flow *flow_get(unsigned int id)
{
struct fio_flow *flow = NULL;
struct flist_head *n;
if (!flow_lock)
return NULL;
fio_mutex_down(flow_lock);
flist_for_each(n, flow_list) {
flow = flist_entry(n, struct fio_flow, list);
if (flow->id == id)
break;
flow = NULL;
}
if (!flow) {
flow = smalloc(sizeof(*flow));
if (!flow) {
log_err("fio: smalloc pool exhausted\n");
return NULL;
}
flow->refs = 0;
INIT_FLIST_HEAD(&flow->list);
flow->id = id;
flow->flow_counter = 0;
flist_add_tail(&flow->list, flow_list);
}
flow->refs++;
fio_mutex_up(flow_lock);
return flow;
}
static void flow_put(struct fio_flow *flow)
{
if (!flow_lock)
return;
fio_mutex_down(flow_lock);
if (!--flow->refs) {
flist_del(&flow->list);
sfree(flow);
}
fio_mutex_up(flow_lock);
}
void flow_init_job(struct thread_data *td)
{
if (td->o.flow)
td->flow = flow_get(td->o.flow_id);
}
void flow_exit_job(struct thread_data *td)
{
if (td->flow) {
flow_put(td->flow);
td->flow = NULL;
}
}
void flow_init(void)
{
flow_list = smalloc(sizeof(*flow_list));
if (!flow_list) {
log_err("fio: smalloc pool exhausted\n");
return;
}
flow_lock = fio_mutex_init(FIO_MUTEX_UNLOCKED);
if (!flow_lock) {
log_err("fio: failed to allocate flow lock\n");
sfree(flow_list);
return;
}
INIT_FLIST_HEAD(flow_list);
}
void flow_exit(void)
{
if (flow_lock)
fio_mutex_remove(flow_lock);
if (flow_list)
sfree(flow_list);
}