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path: root/kernel/trace/ring_buffer_benchmark.c
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Diffstat (limited to 'kernel/trace/ring_buffer_benchmark.c')
-rw-r--r--kernel/trace/ring_buffer_benchmark.c138
1 files changed, 105 insertions, 33 deletions
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 8d68e149a8b..0434ff1b808 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -8,6 +8,7 @@
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/time.h>
+#include <asm/local.h>
struct rb_page {
u64 ts;
@@ -35,6 +36,28 @@ static int disable_reader;
module_param(disable_reader, uint, 0644);
MODULE_PARM_DESC(disable_reader, "only run producer");
+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 = MAX_NICE;
+static int consumer_nice = MAX_NICE;
+
+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;
@@ -58,7 +81,7 @@ static enum event_status read_event(int cpu)
int *entry;
u64 ts;
- event = ring_buffer_consume(buffer, cpu, &ts);
+ event = ring_buffer_consume(buffer, cpu, &ts, NULL);
if (!event)
return EVENT_DROPPED;
@@ -83,14 +106,15 @@ static enum event_status read_page(int cpu)
int inc;
int i;
- bpage = ring_buffer_alloc_read_page(buffer);
+ bpage = ring_buffer_alloc_read_page(buffer, cpu);
if (!bpage)
return EVENT_DROPPED;
ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1);
if (ret >= 0) {
rpage = bpage;
- commit = local_read(&rpage->commit);
+ /* The commit may have missed event flags set, clear them */
+ commit = local_read(&rpage->commit) & 0xfffff;
for (i = 0; i < commit && !kill_test; i += inc) {
if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) {
@@ -102,8 +126,10 @@ static enum event_status read_page(int cpu)
event = (void *)&rpage->data[i];
switch (event->type_len) {
case RINGBUF_TYPE_PADDING:
- /* We don't expect any padding */
- KILL_TEST();
+ /* failed writes may be discarded events */
+ if (!event->time_delta)
+ KILL_TEST();
+ inc = event->array[0] + 4;
break;
case RINGBUF_TYPE_TIME_EXTEND:
inc = 8;
@@ -119,7 +145,7 @@ static enum event_status read_page(int cpu)
KILL_TEST();
break;
}
- inc = event->array[0];
+ inc = event->array[0] + 4;
break;
default:
entry = ring_buffer_event_data(event);
@@ -201,20 +227,23 @@ static void ring_buffer_producer(void)
* Hammer the buffer for 10 secs (this may
* make the system stall)
*/
- pr_info("Starting ring buffer hammer\n");
+ trace_printk("Starting ring buffer hammer\n");
do_gettimeofday(&start_tv);
do {
struct ring_buffer_event *event;
int *entry;
-
- event = ring_buffer_lock_reserve(buffer, 10);
- if (!event) {
- missed++;
- } else {
- hit++;
- entry = ring_buffer_event_data(event);
- *entry = smp_processor_id();
- ring_buffer_unlock_commit(buffer, event);
+ int i;
+
+ for (i = 0; i < write_iteration; i++) {
+ event = ring_buffer_lock_reserve(buffer, 10);
+ if (!event) {
+ missed++;
+ } else {
+ hit++;
+ entry = ring_buffer_event_data(event);
+ *entry = smp_processor_id();
+ ring_buffer_unlock_commit(buffer, event);
+ }
}
do_gettimeofday(&end_tv);
@@ -237,7 +266,7 @@ static void ring_buffer_producer(void)
#endif
} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
- pr_info("End ring buffer hammer\n");
+ trace_printk("End ring buffer hammer\n");
if (consumer) {
/* Init both completions here to avoid races */
@@ -260,49 +289,71 @@ static void ring_buffer_producer(void)
overruns = ring_buffer_overruns(buffer);
if (kill_test)
- pr_info("ERROR!\n");
- pr_info("Time: %lld (usecs)\n", time);
- pr_info("Overruns: %lld\n", overruns);
+ 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 == MAX_NICE && consumer_nice == MAX_NICE)
+ 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)
- pr_info("Read: (reader disabled)\n");
+ trace_printk("Read: (reader disabled)\n");
else
- pr_info("Read: %ld (by %s)\n", read,
+ trace_printk("Read: %ld (by %s)\n", read,
read_events ? "events" : "pages");
- pr_info("Entries: %lld\n", entries);
- pr_info("Total: %lld\n", entries + overruns + read);
- pr_info("Missed: %ld\n", missed);
- pr_info("Hit: %ld\n", hit);
+ trace_printk("Entries: %lld\n", entries);
+ trace_printk("Total: %lld\n", entries + overruns + read);
+ trace_printk("Missed: %ld\n", missed);
+ trace_printk("Hit: %ld\n", hit);
/* Convert time from usecs to millisecs */
do_div(time, USEC_PER_MSEC);
if (time)
hit /= (long)time;
else
- pr_info("TIME IS ZERO??\n");
+ trace_printk("TIME IS ZERO??\n");
- pr_info("Entries per millisec: %ld\n", hit);
+ trace_printk("Entries per millisec: %ld\n", hit);
if (hit) {
/* Calculate the average time in nanosecs */
avg = NSEC_PER_MSEC / hit;
- pr_info("%ld ns per entry\n", avg);
+ trace_printk("%ld ns per entry\n", avg);
}
if (missed) {
if (time)
missed /= (long)time;
- pr_info("Total iterations per millisec: %ld\n", hit + missed);
+ trace_printk("Total iterations per millisec: %ld\n",
+ hit + missed);
/* it is possible that hit + missed will overflow and be zero */
if (!(hit + missed)) {
- pr_info("hit + missed overflowed and totalled zero!\n");
+ trace_printk("hit + missed overflowed and totalled zero!\n");
hit--; /* make it non zero */
}
/* Caculate the average time in nanosecs */
avg = NSEC_PER_MSEC / (hit + missed);
- pr_info("%ld ns per entry\n", avg);
+ trace_printk("%ld ns per entry\n", avg);
}
}
@@ -353,7 +404,7 @@ static int ring_buffer_producer_thread(void *arg)
ring_buffer_producer();
- pr_info("Sleeping for 10 secs\n");
+ trace_printk("Sleeping for 10 secs\n");
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ * SLEEP_TIME);
__set_current_state(TASK_RUNNING);
@@ -389,6 +440,27 @@ static int __init ring_buffer_benchmark_init(void)
if (IS_ERR(producer))
goto out_kill;
+ /*
+ * Run them as low-prio background tasks by default:
+ */
+ 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;
out_kill:
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-07 01:19:54 +0000