/*
* Copyright (c) 2004-2007 Voltaire, Inc. All rights reserved.
* Copyright (c) 2002-2005 Mellanox Technologies LTD. All rights reserved.
* Copyright (c) 1996-2003 Intel Corporation. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - 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.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#if HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <math.h>
#include <stdlib.h>
#ifdef __CL_EVENT_WHEEL_TEST__
#include <unistd.h> /* sleep() */
#endif
#include <complib/cl_event_wheel.h>
#include <complib/cl_debug.h>
#define CL_DBG(fmt, ...)
static cl_status_t __event_will_age_before(IN const cl_list_item_t *
const p_list_item, IN void *context)
{
uint64_t aging_time = *((uint64_t *) context);
cl_event_wheel_reg_info_t *p_event;
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t, list_item);
if (p_event->aging_time < aging_time)
return CL_SUCCESS;
else
return CL_NOT_FOUND;
}
static void __cl_event_wheel_callback(IN void *context)
{
cl_event_wheel_t *p_event_wheel = (cl_event_wheel_t *) context;
cl_list_item_t *p_list_item, *p_prev_event_list_item;
cl_list_item_t *p_list_next_item;
cl_event_wheel_reg_info_t *p_event;
uint64_t current_time;
uint64_t next_aging_time;
uint32_t new_timeout;
cl_status_t cl_status;
/* might be during closing ... */
if (p_event_wheel->closing)
return;
current_time = cl_get_time_stamp();
if (NULL != p_event_wheel->p_external_lock)
/* Take care of the order of acquiring locks to avoid the deadlock!
* The external lock goes first.
*/
cl_spinlock_acquire(p_event_wheel->p_external_lock);
cl_spinlock_acquire(&p_event_wheel->lock);
p_list_item = cl_qlist_head(&p_event_wheel->events_wheel);
if (p_list_item == cl_qlist_end(&p_event_wheel->events_wheel))
/* the list is empty - nothing to do */
goto Exit;
/* we found such an item. get the p_event */
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t, list_item);
while (p_event->aging_time <= current_time) {
/* this object has aged - invoke it's callback */
if (p_event->pfn_aged_callback)
next_aging_time =
p_event->pfn_aged_callback(p_event->key,
p_event->num_regs,
p_event->context);
else
next_aging_time = 0;
/* point to the next object in the wheel */
p_list_next_item = cl_qlist_next(p_list_item);
/* We need to retire the event if the next aging time passed */
if (next_aging_time < current_time) {
/* remove it from the map */
cl_qmap_remove_item(&p_event_wheel->events_map,
&(p_event->map_item));
/* pop p_event from the wheel */
cl_qlist_remove_head(&p_event_wheel->events_wheel);
/* delete the event info object - allocated by cl_event_wheel_reg */
free(p_event);
} else {
/* update the required aging time */
p_event->aging_time = next_aging_time;
p_event->num_regs++;
/* do not remove from the map - but remove from the list head and
place in the correct position */
/* pop p_event from the wheel */
cl_qlist_remove_head(&p_event_wheel->events_wheel);
/* find the event that ages just before */
p_prev_event_list_item =
cl_qlist_find_from_tail(&p_event_wheel->
events_wheel,
__event_will_age_before,
&p_event->aging_time);
/* insert just after */
cl_qlist_insert_next(&p_event_wheel->events_wheel,
p_prev_event_list_item,
&p_event->list_item);
/* as we have modified the list - restart from first item: */
p_list_next_item =
cl_qlist_head(&p_event_wheel->events_wheel);
}
/* advance to next event */
p_list_item = p_list_next_item;
if (p_list_item == cl_qlist_end(&p_event_wheel->events_wheel))
/* the list is empty - nothing to do */
break;
/* get the p_event */
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t,
list_item);
}
/* We need to restart the timer only if the list is not empty now */
if (p_list_item != cl_qlist_end(&p_event_wheel->events_wheel)) {
/* get the p_event */
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t,
list_item);
/* start the timer to the timeout [msec] */
new_timeout =
(uint32_t) ((p_event->aging_time - current_time + 500) / 1000);
CL_DBG("__cl_event_wheel_callback: Restart timer in: "
"%u [msec]\n", new_timeout);
cl_status = cl_timer_start(&p_event_wheel->timer, new_timeout);
if (cl_status != CL_SUCCESS) {
CL_DBG("__cl_event_wheel_callback: ERR 6200: "
"Failed to start timer\n");
}
}
/* release the lock */
Exit:
cl_spinlock_release(&p_event_wheel->lock);
if (NULL != p_event_wheel->p_external_lock)
cl_spinlock_release(p_event_wheel->p_external_lock);
}
/*
* Construct and Initialize
*/
void cl_event_wheel_construct(IN cl_event_wheel_t * const p_event_wheel)
{
cl_spinlock_construct(&(p_event_wheel->lock));
cl_timer_construct(&(p_event_wheel->timer));
}
cl_status_t cl_event_wheel_init(IN cl_event_wheel_t * const p_event_wheel)
{
cl_status_t cl_status = CL_SUCCESS;
/* initialize */
p_event_wheel->p_external_lock = NULL;
p_event_wheel->closing = FALSE;
cl_status = cl_spinlock_init(&(p_event_wheel->lock));
if (cl_status != CL_SUCCESS)
return cl_status;
cl_qlist_init(&p_event_wheel->events_wheel);
cl_qmap_init(&p_event_wheel->events_map);
/* init the timer with timeout */
cl_status = cl_timer_init(&p_event_wheel->timer, __cl_event_wheel_callback, p_event_wheel); /* cb context */
return cl_status;
}
cl_status_t cl_event_wheel_init_ex(IN cl_event_wheel_t * const p_event_wheel,
IN cl_spinlock_t * p_external_lock)
{
cl_status_t cl_status;
cl_status = cl_event_wheel_init(p_event_wheel);
if (CL_SUCCESS != cl_status)
return cl_status;
p_event_wheel->p_external_lock = p_external_lock;
return cl_status;
}
void cl_event_wheel_dump(IN cl_event_wheel_t * const p_event_wheel)
{
cl_list_item_t *p_list_item;
cl_event_wheel_reg_info_t __attribute__((__unused__)) *p_event;
p_list_item = cl_qlist_head(&p_event_wheel->events_wheel);
while (p_list_item != cl_qlist_end(&p_event_wheel->events_wheel)) {
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t,
list_item);
CL_DBG("cl_event_wheel_dump: Found event key:<0x%"
PRIx64 ">, num_regs:%d, aging time:%" PRIu64 "\n",
p_event->key, p_event->num_regs, p_event->aging_time);
p_list_item = cl_qlist_next(p_list_item);
}
}
void cl_event_wheel_destroy(IN cl_event_wheel_t * const p_event_wheel)
{
cl_list_item_t *p_list_item;
cl_map_item_t *p_map_item;
cl_event_wheel_reg_info_t *p_event;
/* we need to get a lock */
cl_spinlock_acquire(&p_event_wheel->lock);
cl_event_wheel_dump(p_event_wheel);
/* go over all the items in the list and remove them */
p_list_item = cl_qlist_remove_head(&p_event_wheel->events_wheel);
while (p_list_item != cl_qlist_end(&p_event_wheel->events_wheel)) {
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t,
list_item);
CL_DBG("cl_event_wheel_destroy: Found outstanding event"
" key:<0x%" PRIx64 ">\n", p_event->key);
/* remove it from the map */
p_map_item = &(p_event->map_item);
cl_qmap_remove_item(&p_event_wheel->events_map, p_map_item);
free(p_event); /* allocated by cl_event_wheel_reg */
p_list_item =
cl_qlist_remove_head(&p_event_wheel->events_wheel);
}
/* destroy the timer */
cl_timer_destroy(&p_event_wheel->timer);
/* destroy the lock (this should be done without releasing - we don't want
any other run to grab the lock at this point. */
cl_spinlock_release(&p_event_wheel->lock);
cl_spinlock_destroy(&(p_event_wheel->lock));
}
cl_status_t cl_event_wheel_reg(IN cl_event_wheel_t * const p_event_wheel,
IN const uint64_t key,
IN const uint64_t aging_time_usec,
IN cl_pfn_event_aged_cb_t pfn_callback,
IN void *const context)
{
cl_event_wheel_reg_info_t *p_event;
uint64_t timeout;
uint32_t to;
cl_status_t cl_status = CL_SUCCESS;
cl_list_item_t *prev_event_list_item;
cl_map_item_t *p_map_item;
/* Get the lock on the manager */
cl_spinlock_acquire(&(p_event_wheel->lock));
cl_event_wheel_dump(p_event_wheel);
/* Make sure such a key does not exists */
p_map_item = cl_qmap_get(&p_event_wheel->events_map, key);
if (p_map_item != cl_qmap_end(&p_event_wheel->events_map)) {
CL_DBG("cl_event_wheel_reg: Already existing key:0x%"
PRIx64 "\n", key);
/* already there - remove it from the list as it is getting a new time */
p_event =
PARENT_STRUCT(p_map_item, cl_event_wheel_reg_info_t,
map_item);
/* remove the item from the qlist */
cl_qlist_remove_item(&p_event_wheel->events_wheel,
&p_event->list_item);
/* and the qmap */
cl_qmap_remove_item(&p_event_wheel->events_map,
&p_event->map_item);
} else {
/* make a new one */
p_event = (cl_event_wheel_reg_info_t *)
malloc(sizeof(cl_event_wheel_reg_info_t));
if (!p_event) {
cl_status = CL_ERROR;
goto Exit;
}
p_event->num_regs = 0;
}
p_event->key = key;
p_event->aging_time = aging_time_usec;
p_event->pfn_aged_callback = pfn_callback;
p_event->context = context;
p_event->num_regs++;
CL_DBG("cl_event_wheel_reg: Registering event key:0x%" PRIx64
" aging in %u [msec]\n", p_event->key,
(uint32_t) ((p_event->aging_time - cl_get_time_stamp()) / 1000));
/* If the list is empty - need to start the timer */
if (cl_is_qlist_empty(&p_event_wheel->events_wheel)) {
/* Edward Bortnikov 03/29/2003
* ++TBD Consider moving the timer manipulation behind the list manipulation.
*/
/* calculate the new timeout */
timeout =
(p_event->aging_time - cl_get_time_stamp() + 500) / 1000;
/* stop the timer if it is running */
/* Edward Bortnikov 03/29/2003
* Don't call cl_timer_stop() because it spins forever.
* cl_timer_start() will invoke cl_timer_stop() by itself.
*
* The problematic scenario is when __cl_event_wheel_callback()
* is in race condition with this code. It sets timer.in_timer_cb
* to TRUE and then blocks on p_event_wheel->lock. Following this,
* the call to cl_timer_stop() hangs. Following this, the whole system
* enters into a deadlock.
*
* cl_timer_stop(&p_event_wheel->timer);
*/
/* The timeout for the cl_timer_start should be given as uint32_t.
if there is an overflow - warn about it. */
to = (uint32_t) timeout;
if (timeout > (uint32_t) timeout) {
to = 0xffffffff; /* max 32 bit timer */
CL_DBG("cl_event_wheel_reg: timeout requested is "
"too large. Using timeout: %u\n", to);
}
/* start the timer to the timeout [msec] */
cl_status = cl_timer_start(&p_event_wheel->timer, to);
if (cl_status != CL_SUCCESS) {
CL_DBG("cl_event_wheel_reg : ERR 6203: "
"Failed to start timer\n");
goto Exit;
}
}
/* insert the object to the qlist and the qmap */
/* BUT WE MUST INSERT IT IN A SORTED MANNER */
prev_event_list_item =
cl_qlist_find_from_tail(&p_event_wheel->events_wheel,
__event_will_age_before,
&p_event->aging_time);
cl_qlist_insert_next(&p_event_wheel->events_wheel,
prev_event_list_item, &p_event->list_item);
cl_qmap_insert(&p_event_wheel->events_map, key, &(p_event->map_item));
Exit:
cl_spinlock_release(&p_event_wheel->lock);
return cl_status;
}
void cl_event_wheel_unreg(IN cl_event_wheel_t * const p_event_wheel,
IN uint64_t key)
{
cl_event_wheel_reg_info_t *p_event;
cl_map_item_t *p_map_item;
CL_DBG("cl_event_wheel_unreg: " "Removing key:0x%" PRIx64 "\n", key);
cl_spinlock_acquire(&p_event_wheel->lock);
p_map_item = cl_qmap_get(&p_event_wheel->events_map, key);
if (p_map_item != cl_qmap_end(&p_event_wheel->events_map)) {
/* we found such an item. */
p_event =
PARENT_STRUCT(p_map_item, cl_event_wheel_reg_info_t,
map_item);
/* remove the item from the qlist */
cl_qlist_remove_item(&p_event_wheel->events_wheel,
&(p_event->list_item));
/* remove the item from the qmap */
cl_qmap_remove_item(&p_event_wheel->events_map,
&(p_event->map_item));
CL_DBG("cl_event_wheel_unreg: Removed key:0x%" PRIx64 "\n",
key);
/* free the item */
free(p_event);
} else {
CL_DBG("cl_event_wheel_unreg: did not find key:0x%" PRIx64
"\n", key);
}
cl_spinlock_release(&p_event_wheel->lock);
}
uint32_t cl_event_wheel_num_regs(IN cl_event_wheel_t * const p_event_wheel,
IN uint64_t key)
{
cl_event_wheel_reg_info_t *p_event;
cl_map_item_t *p_map_item;
uint32_t num_regs = 0;
/* try to find the key in the map */
CL_DBG("cl_event_wheel_num_regs: Looking for key:0x%" PRIx64 "\n", key);
cl_spinlock_acquire(&p_event_wheel->lock);
p_map_item = cl_qmap_get(&p_event_wheel->events_map, key);
if (p_map_item != cl_qmap_end(&p_event_wheel->events_map)) {
/* ok so we can simply return it's num_regs */
p_event =
PARENT_STRUCT(p_map_item, cl_event_wheel_reg_info_t,
map_item);
num_regs = p_event->num_regs;
}
cl_spinlock_release(&p_event_wheel->lock);
return (num_regs);
}
#ifdef __CL_EVENT_WHEEL_TEST__
/* Dump out the complete state of the event wheel */
void __cl_event_wheel_dump(IN cl_event_wheel_t * const p_event_wheel)
{
cl_list_item_t *p_list_item;
cl_map_item_t *p_map_item;
cl_event_wheel_reg_info_t *p_event;
printf("************** Event Wheel Dump ***********************\n");
printf("Event Wheel List has %u items:\n",
cl_qlist_count(&p_event_wheel->events_wheel));
p_list_item = cl_qlist_head(&p_event_wheel->events_wheel);
while (p_list_item != cl_qlist_end(&p_event_wheel->events_wheel)) {
p_event =
PARENT_STRUCT(p_list_item, cl_event_wheel_reg_info_t,
list_item);
printf("Event key:0x%" PRIx64 " Context:%s NumRegs:%u\n",
p_event->key, (char *)p_event->context,
p_event->num_regs);
/* next */
p_list_item = cl_qlist_next(p_list_item);
}
printf("Event Map has %u items:\n",
cl_qmap_count(&p_event_wheel->events_map));
p_map_item = cl_qmap_head(&p_event_wheel->events_map);
while (p_map_item != cl_qmap_end(&p_event_wheel->events_map)) {
p_event =
PARENT_STRUCT(p_map_item, cl_event_wheel_reg_info_t,
map_item);
printf("Event key:0x%" PRIx64 " Context:%s NumRegs:%u\n",
p_event->key, (char *)p_event->context,
p_event->num_regs);
/* next */
p_map_item = cl_qmap_next(p_map_item);
}
}
/* The callback for aging event */
/* We assume we pass a text context */
static uint64_t __test_event_aging(uint64_t key, uint32_t num_regs, void *context)
{
printf("*****************************************************\n");
printf("Aged key: 0x%" PRIx64 " Context:%s\n", key, (char *) context);
}
int main()
{
cl_event_wheel_t event_wheel;
/* init complib */
if (complib_init_v2() != CL_SUCCESS) {
printf("complib_init_v2 failed\n");
exit(1);
}
/* construct */
cl_event_wheel_construct(&event_wheel);
/* init */
cl_event_wheel_init(&event_wheel);
/* Start Playing */
cl_event_wheel_reg(&event_wheel, 1, /* key */
cl_get_time_stamp() + 3000000, /* 3 sec lifetime */
__test_event_aging, /* cb */
"The First Aging Event");
cl_event_wheel_reg(&event_wheel, 2, /* key */
cl_get_time_stamp() + 3000000, /* 3 sec lifetime */
__test_event_aging, /* cb */
"The Second Aging Event");
cl_event_wheel_reg(&event_wheel, 3, /* key */
cl_get_time_stamp() + 3500000, /* 3.5 sec lifetime */
__test_event_aging, /* cb */
"The Third Aging Event");
__cl_event_wheel_dump(&event_wheel);
sleep(2);
cl_event_wheel_reg(&event_wheel, 2, /* key */
cl_get_time_stamp() + 8000000, /* 8 sec lifetime */
__test_event_aging, /* cb */
"The Second Aging Event Moved");
__cl_event_wheel_dump(&event_wheel);
sleep(1);
/* remove the third event */
cl_event_wheel_unreg(&event_wheel, 3); /* key */
/* get the number of registrations for the keys */
printf("Event 1 Registered: %u\n",
cl_event_wheel_num_regs(&event_wheel, 1));
printf("Event 2 Registered: %u\n",
cl_event_wheel_num_regs(&event_wheel, 2));
sleep(5);
/* destroy */
cl_event_wheel_destroy(&event_wheel);
complib_exit();
return (0);
}
#endif /* __CL_EVENT_WHEEL_TEST__ */