135 lines
3.6 KiB
C
135 lines
3.6 KiB
C
|
|
/*
|
|
* Copyright (c) 2017, GlobalLogic Ukraine LLC
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the GlobalLogic.
|
|
* 4. Neither the name of the GlobalLogic nor the
|
|
* names of its contributors may be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY GLOBALLOGIC UKRAINE LLC ``AS IS`` AND ANY
|
|
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL GLOBALLOGIC UKRAINE LLC BE LIABLE FOR ANY
|
|
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/printk.h>
|
|
#include <linux/slab.h>
|
|
|
|
MODULE_AUTHOR("Serhii Popovych <serhii.popovych@globallogic.com>");
|
|
MODULE_DESCRIPTION("Hello, world in Linux Kernel Training");
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
|
|
|
struct TimingList {
|
|
struct TimingList *next;
|
|
ktime_t t;
|
|
};
|
|
|
|
static unsigned int msg_count = 1;
|
|
static struct TimingList *tl_head;
|
|
|
|
static void init_new_list(void)
|
|
{
|
|
tl_head = kmalloc(sizeof(struct TimingList), GFP_KERNEL);
|
|
|
|
tl_head->next = NULL;
|
|
tl_head->t = ktime_get();
|
|
}
|
|
|
|
static void insert_new_time(void)
|
|
{
|
|
struct TimingList *last_tl_node = tl_head;
|
|
struct TimingList *new_tl_node = kmalloc(sizeof(struct TimingList),
|
|
GFP_KERNEL);
|
|
|
|
while (last_tl_node->next != NULL)
|
|
last_tl_node = last_tl_node->next;
|
|
|
|
|
|
new_tl_node->next = NULL;
|
|
new_tl_node->t = ktime_get();
|
|
|
|
last_tl_node->next = new_tl_node;
|
|
}
|
|
|
|
static void print_time(ktime_t *t)
|
|
{
|
|
printk(KERN_EMERG "%lld\n", *t);
|
|
}
|
|
|
|
static void destroy_list(void)
|
|
{
|
|
struct TimingList *curr_tl = tl_head;
|
|
struct TimingList *next_tl = NULL;
|
|
|
|
while (curr_tl != NULL) {
|
|
print_time(&(curr_tl->t));
|
|
|
|
next_tl = curr_tl->next;
|
|
kfree(curr_tl);
|
|
curr_tl = next_tl;
|
|
}
|
|
}
|
|
|
|
static void update_timing_list(void)
|
|
{
|
|
if (tl_head == NULL)
|
|
init_new_list();
|
|
else
|
|
insert_new_time();
|
|
}
|
|
|
|
static int __init hello_init(void)
|
|
{
|
|
int i;
|
|
|
|
if (msg_count > 10) {
|
|
printk(KERN_EMERG "Error: msg_count too large (%d > 10)\n",
|
|
msg_count);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (msg_count == 0 || msg_count >= 5) {
|
|
printk(KERN_EMERG "Warning: msg_count = %d "
|
|
"(msg_count == 0 or 5 <= msg_count <= 10)\n",
|
|
msg_count);
|
|
}
|
|
|
|
for (i = 0; i < msg_count; i++) {
|
|
update_timing_list();
|
|
|
|
printk(KERN_EMERG "Hello, world!\n");
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit hello_exit(void)
|
|
{
|
|
destroy_list();
|
|
}
|
|
|
|
module_param(msg_count, uint, 0444);
|
|
MODULE_PARM_DESC(msg_count, "Amount of hello world outputs on load");
|
|
|
|
module_init(hello_init);
|
|
module_exit(hello_exit);
|