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/* IBM_PROLOG_BEGIN_TAG */
/* This is an automatically generated prolog. */
/* */
/* $Source: src/kernel/timemgr.C $ */
/* */
/* OpenPOWER HostBoot Project */
/* */
/* Contributors Listed Below - COPYRIGHT 2010,2016 */
/* [+] International Business Machines Corp. */
/* */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or */
/* implied. See the License for the specific language governing */
/* permissions and limitations under the License. */
/* */
/* IBM_PROLOG_END_TAG */
#include <kernel/timemgr.H>
#include <kernel/scheduler.H>
#include <util/singleton.H>
#include <kernel/task.H>
#include <kernel/cpumgr.H>
#include <util/misc.H>
#include <kernel/misc.H>
#include <sys/task.h>
#include <kernel/doorbell.H>
uint64_t TimeManager::iv_timebaseFreq = 0xFFFFFFFF;
bool TimeManager::cv_isSimicsRunning = Util::isSimicsRunning();
void TimeManager::init()
{
Singleton<TimeManager>::instance()._init();
}
void TimeManager::_init()
{
iv_timebaseFreq = 512000000ULL;
}
void TimeManager::init_cpu(cpu_t* cpu)
{
Singleton<TimeManager>::instance()._init_cpu(cpu);
}
void TimeManager::_init_cpu(cpu_t* cpu)
{
cpu->delay_list = new delaylist_t();
}
uint64_t TimeManager::convertSecToTicks(uint64_t i_sec, uint64_t i_nsec)
{
// This code will handle times almost up to a year without overflowing a
// uint64. This should be more than sufficient for our purposes.
// Result = ((sec * 10^9 + nsec) * tb) / 10^9.
uint64_t result = ((i_sec * 1000000000ULL) + i_nsec);
result *= (iv_timebaseFreq / 1000000);
result /= 1000;
return result;
}
void TimeManager::convertTicksToSec(uint64_t i_ticks,
uint64_t& o_sec, uint64_t& o_nsec)
{
o_sec = i_ticks / iv_timebaseFreq;
o_nsec = (i_ticks - (o_sec * iv_timebaseFreq)) * 1000;
o_nsec /= (iv_timebaseFreq / 1000000);
}
void TimeManager::delayTask(task_t* t, uint64_t i_sec, uint64_t i_nsec)
{
Singleton<TimeManager>::instance()._delayTask(t,i_sec,i_nsec);
}
void TimeManager::_delayTask(task_t* t, uint64_t i_sec, uint64_t i_nsec)
{
_TimeManager_Delay_t* node = new _TimeManager_Delay_t();
node->key = this->getCurrentTimeBase() +
this->convertSecToTicks(i_sec, i_nsec);
node->task = t;
t->state = TASK_STATE_BLOCK_SLEEP;
t->state_info = (void*)node->key;
_get_delaylist()->insert(node);
}
void TimeManager::checkReleaseTasks(Scheduler* s)
{
Singleton<TimeManager>::instance()._checkReleaseTasks(s);
}
void TimeManager::_checkReleaseTasks(Scheduler* s)
{
uint64_t l_currentTime = getCurrentTimeBase();
_TimeManager_Delay_t* node = NULL;
while(NULL != (node = _get_delaylist()->remove_if(l_currentTime)))
{
s->addTask(node->task);
delete node;
doorbell_broadcast();
}
}
TimeManager::delaylist_t* TimeManager::_get_delaylist()
{
return static_cast<delaylist_t*>(CpuManager::getCurrentCPU()->delay_list);
}
uint64_t TimeManager::getIdleTimeSliceCount()
{
uint64_t sliceCount = getTimeSliceCount();
// In Simics we want to idle longer to improve overall performance. Set
// the idle baseline at 10x normal idle frequency.
if (cv_isSimicsRunning)
{
sliceCount *= 10;
}
// Get a delayed task, if there is one
_TimeManager_Delay_t* node = _get_delaylist()->front();
if(node)
{
uint64_t currentTime = getCurrentTimeBase();
if(currentTime < node->key)
{
uint64_t diffTime = node->key - currentTime;
if(diffTime < sliceCount)
{
sliceCount = diffTime;
}
}
else // ready to run now! Minimum delay
{
sliceCount = 1;
}
}
return sliceCount;
}
bool TimeManager::simpleDelay(uint64_t i_sec, uint64_t i_nsec)
{
bool result = false;
uint64_t threshold = getTimeSliceCount()/YIELD_THRESHOLD_PER_SLICE;
uint64_t delay = convertSecToTicks(i_sec, i_nsec);
bool isUserspace = !KernelMisc::in_kernel_mode();
// TB is not synchronized between cores, so if we're doing a poll we need
// to pin the task to the current cpu. Otherwise the getTB can get a
// drifted answer after a task migration.
if (isUserspace)
{
task_affinity_pin();
}
// Do polling delay.
if(delay < threshold)
{
uint64_t expire = getCurrentTimeBase() + delay;
while(getCurrentTimeBase() < expire)
{
setThreadPriorityLow();
}
setThreadPriorityHigh();
result = true;
}
if (isUserspace)
{
task_affinity_unpin();
}
return result;
}
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