RIOT-OS/RIOT
RIOT-OS/RIOT
1
0
Fork 0
mirror of https://github.com/RIOT-OS/RIOT.git synced 2024-12-29 04:50:03 +01:00
Code Releases Activity

tests/thread_float: do not overload slow MCUs with IRQs

Browse Source 
If the regular context switches are triggered too fast, slow MCUs
will be able to spent little time on actually progressing in the
test. This will scale the IRQ rate with the CPU clock as a crude way
too keep load within limits.
This commit is contained in:
Marian Buschsieweke 2022-09-23 13:49:45 +02:00
parent bf20287229
commit 0835466498
No known key found for this signature in database
GPG Key ID: CB8E3238CE715A94
1 changed files with 22 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
tests/thread_float/main.c
View File

@ -23,10 +23,14 @@
#include <stdio.h>
#include <string.h>
#include "thread.h"
#include "board.h"
#include "clk.h"
#include "macros/units.h"
#include "msg.h"
#include "periph_conf.h"
#include "thread.h"
#include "time_units.h"
#include "ztimer.h"
#include "timex.h"
static char t1_stack[THREAD_STACKSIZE_MAIN];
static char t2_stack[THREAD_STACKSIZE_MAIN];
@ -36,15 +40,13 @@ static kernel_pid_t p1, p2, p3;
static ztimer_t timer;
#define OFFSET (100)
static mutex_t lock = MUTEX_INIT;
static void timer_cb(void *arg)
{
(void)arg;
uint32_t *timeout = arg;
thread_yield();
ztimer_set(ZTIMER_USEC, &timer, OFFSET);
ztimer_set(ZTIMER_USEC, &timer, *timeout);
}
static void *thread_1_2_3(void *_arg)
@ -81,6 +83,16 @@ int main(void)
const char *t2_name = "t2";
const char *t3_name = "t3";
/* Let's not overwhelm boards by firing IRQs faster than they can handle and
* give them 50 billion CPU cycles per timeout.
*
* (Note: The `static` is required as this variable will be accessed from
* the ISR, which will occur even after the main thread has exited.) */
static uint32_t timeout = 0;
/* Note: It must be initialized dynamically, as coreclk() is not
* constant. */
timeout = 50000000000U / coreclk();
p1 = thread_create(t1_stack, sizeof(t1_stack), THREAD_PRIORITY_MAIN + 1,
THREAD_CREATE_WOUT_YIELD | THREAD_CREATE_STACKTEST,
thread_1_2_3, (void *)t1_name, t1_name);
@ -92,8 +104,11 @@ int main(void)
thread_1_2_3, (void *)t3_name, t3_name);
puts("THREADS CREATED\n");
printf("Context switch every %" PRIu32 " µs\n", timeout);
timer.callback = timer_cb;
ztimer_set(ZTIMER_USEC, &timer, OFFSET);
timer.arg = &timeout;
ztimer_set(ZTIMER_USEC, &timer, timeout);
return 0;
}