ring-buffer-benchmark: Add parameters to set produce/consumer priorities

Running the ring-buffer-benchmark's threads at the lowest priority may
work well for keeping it in the background, but it is not appropriate
for the benchmarks.

This patch adds 4 parameters to the module:

  consumer_fifo
  consumer_nice
  producer_fifo
  producer_nice

By default the consumer and producer still run at nice +19.

If the *_fifo options are set, they will override the *_nice values.

 modprobe ring_buffer_benchmark consumer_nice=0 producer_fifo=10

The above will set the consumer thread to a nice value of 0, and
the producer thread to a RT SCHED_FIFO priority of 10.

Note, this patch also fixes a bug where calling set_user_nice on the
consumer thread would oops the kernel when the parameter "disable_reader"
is set.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt 2009-11-25 13:22:21 -05:00 committed by Steven Rostedt
parent 457dc928f5
commit 7ac0743404

View File

@ -39,6 +39,24 @@ static int write_iteration = 50;
module_param(write_iteration, uint, 0644);
MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");
static int producer_nice = 19;
static int consumer_nice = 19;
static int producer_fifo = -1;
static int consumer_fifo = -1;
module_param(producer_nice, uint, 0644);
MODULE_PARM_DESC(producer_nice, "nice prio for producer");
module_param(consumer_nice, uint, 0644);
MODULE_PARM_DESC(consumer_nice, "nice prio for consumer");
module_param(producer_fifo, uint, 0644);
MODULE_PARM_DESC(producer_fifo, "fifo prio for producer");
module_param(consumer_fifo, uint, 0644);
MODULE_PARM_DESC(consumer_fifo, "fifo prio for consumer");
static int read_events;
static int kill_test;
@ -270,6 +288,27 @@ static void ring_buffer_producer(void)
if (kill_test)
trace_printk("ERROR!\n");
if (!disable_reader) {
if (consumer_fifo < 0)
trace_printk("Running Consumer at nice: %d\n",
consumer_nice);
else
trace_printk("Running Consumer at SCHED_FIFO %d\n",
consumer_fifo);
}
if (producer_fifo < 0)
trace_printk("Running Producer at nice: %d\n",
producer_nice);
else
trace_printk("Running Producer at SCHED_FIFO %d\n",
producer_fifo);
/* Let the user know that the test is running at low priority */
if (producer_fifo < 0 && consumer_fifo < 0 &&
producer_nice == 19 && consumer_nice == 19)
trace_printk("WARNING!!! This test is running at lowest priority.\n");
trace_printk("Time: %lld (usecs)\n", time);
trace_printk("Overruns: %lld\n", overruns);
if (disable_reader)
@ -402,8 +441,23 @@ static int __init ring_buffer_benchmark_init(void)
/*
* Run them as low-prio background tasks by default:
*/
set_user_nice(consumer, 19);
set_user_nice(producer, 19);
if (!disable_reader) {
if (consumer_fifo >= 0) {
struct sched_param param = {
.sched_priority = consumer_fifo
};
sched_setscheduler(consumer, SCHED_FIFO, &param);
} else
set_user_nice(consumer, consumer_nice);
}
if (producer_fifo >= 0) {
struct sched_param param = {
.sched_priority = consumer_fifo
};
sched_setscheduler(producer, SCHED_FIFO, &param);
} else
set_user_nice(producer, producer_nice);
return 0;