07cf835689
Currently kernel HW tracing infrastrtucture and specifically its SyS-T part treats all source data in the same way. Treating and encoding different trace data sources differently might allow decoding software to make use of e.g. ftrace event ids by converting them to a SyS-T message catalog. The solution is to keep source type stored within stm_source_data structure to allow different handling by stm output/protocol. Currently we only differentiate between STM_USER and STM_FTRACE sources. Signed-off-by: Mikhail Lappo <miklelappo@gmail.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240429130119.1518073-3-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
122 lines
2.9 KiB
C
122 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Simple heartbeat STM source driver
|
|
* Copyright (c) 2016, Intel Corporation.
|
|
*
|
|
* Heartbeat STM source will send repetitive messages over STM devices to a
|
|
* trace host.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/hrtimer.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/stm.h>
|
|
|
|
#define STM_HEARTBEAT_MAX 32
|
|
|
|
static int nr_devs = 4;
|
|
static int interval_ms = 10;
|
|
|
|
module_param(nr_devs, int, 0400);
|
|
module_param(interval_ms, int, 0600);
|
|
|
|
static struct stm_heartbeat {
|
|
struct stm_source_data data;
|
|
struct hrtimer hrtimer;
|
|
unsigned int active;
|
|
} stm_heartbeat[STM_HEARTBEAT_MAX];
|
|
|
|
static const char str[] = "heartbeat stm source driver is here to serve you";
|
|
|
|
static enum hrtimer_restart stm_heartbeat_hrtimer_handler(struct hrtimer *hr)
|
|
{
|
|
struct stm_heartbeat *heartbeat = container_of(hr, struct stm_heartbeat,
|
|
hrtimer);
|
|
|
|
stm_source_write(&heartbeat->data, 0, str, sizeof str);
|
|
if (heartbeat->active)
|
|
hrtimer_forward_now(hr, ms_to_ktime(interval_ms));
|
|
|
|
return heartbeat->active ? HRTIMER_RESTART : HRTIMER_NORESTART;
|
|
}
|
|
|
|
static int stm_heartbeat_link(struct stm_source_data *data)
|
|
{
|
|
struct stm_heartbeat *heartbeat =
|
|
container_of(data, struct stm_heartbeat, data);
|
|
|
|
heartbeat->active = 1;
|
|
hrtimer_start(&heartbeat->hrtimer, ms_to_ktime(interval_ms),
|
|
HRTIMER_MODE_ABS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void stm_heartbeat_unlink(struct stm_source_data *data)
|
|
{
|
|
struct stm_heartbeat *heartbeat =
|
|
container_of(data, struct stm_heartbeat, data);
|
|
|
|
heartbeat->active = 0;
|
|
hrtimer_cancel(&heartbeat->hrtimer);
|
|
}
|
|
|
|
static int stm_heartbeat_init(void)
|
|
{
|
|
int i, ret;
|
|
|
|
if (nr_devs < 0 || nr_devs > STM_HEARTBEAT_MAX)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < nr_devs; i++) {
|
|
stm_heartbeat[i].data.name =
|
|
kasprintf(GFP_KERNEL, "heartbeat.%d", i);
|
|
if (!stm_heartbeat[i].data.name) {
|
|
ret = -ENOMEM;
|
|
goto fail_unregister;
|
|
}
|
|
|
|
stm_heartbeat[i].data.nr_chans = 1;
|
|
stm_heartbeat[i].data.type = STM_USER;
|
|
stm_heartbeat[i].data.link = stm_heartbeat_link;
|
|
stm_heartbeat[i].data.unlink = stm_heartbeat_unlink;
|
|
hrtimer_init(&stm_heartbeat[i].hrtimer, CLOCK_MONOTONIC,
|
|
HRTIMER_MODE_ABS);
|
|
stm_heartbeat[i].hrtimer.function =
|
|
stm_heartbeat_hrtimer_handler;
|
|
|
|
ret = stm_source_register_device(NULL, &stm_heartbeat[i].data);
|
|
if (ret)
|
|
goto fail_free;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail_unregister:
|
|
for (i--; i >= 0; i--) {
|
|
stm_source_unregister_device(&stm_heartbeat[i].data);
|
|
fail_free:
|
|
kfree(stm_heartbeat[i].data.name);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void stm_heartbeat_exit(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_devs; i++) {
|
|
stm_source_unregister_device(&stm_heartbeat[i].data);
|
|
kfree(stm_heartbeat[i].data.name);
|
|
}
|
|
}
|
|
|
|
module_init(stm_heartbeat_init);
|
|
module_exit(stm_heartbeat_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_DESCRIPTION("stm_heartbeat driver");
|
|
MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
|