derek/gem5
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

sim-power: Creation of PowerState class

Browse Source 
This commit does not make any functional changes but just rearranges
the existing code with regard to the power states. Previously, all
code regarding power states was in the ClockedObjects. However, it
seems more logical and cleaner to move this code into a separate
class, called PowerState. The PowerState is a now SimObject. Every
ClockedObject has a PowerState but this patch also allows for objects
with PowerState which are not ClockedObjects.

Change-Id: Id2db86dc14f140dc9d0912a8a7de237b9df9120d
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28049
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit is contained in:
Anouk Van Laer
2017-10-04 14:14:33 +01:00
committed by Nikos Nikoleris
parent 84003b7cc7
commit 818961969a
11 changed files with 432 additions and 231 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
configs/example/arm/fs_power.py
View File

@@ -114,7 +114,7 @@ def main():
if not isinstance(cpu, m5.objects.BaseCPU):
continue
cpu.default_p_state = "ON"
cpu.power_state.default_state = "ON"
cpu.power_model = CpuPowerModel(cpu.path())
# Example power model for the L2 Cache of the bigCluster
@@ -122,7 +122,7 @@ def main():
if not isinstance(l2, m5.objects.Cache):
continue
l2.default_p_state = "ON"
l2.power_state.default_state = "ON"
l2.power_model = L2PowerModel(l2.path())
bL.instantiate(options)

18
src/cpu/base.cc
View File

@@ -329,11 +329,11 @@ BaseCPU::startup()
}
if (_switchedOut)
ClockedObject::pwrState(Enums::PwrState::OFF);
powerState->set(Enums::PwrState::OFF);
// Assumption CPU start to operate instantaneously without any latency
if (ClockedObject::pwrState() == Enums::PwrState::UNDEFINED)
ClockedObject::pwrState(Enums::PwrState::ON);
if (powerState->get() == Enums::PwrState::UNDEFINED)
powerState->set(Enums::PwrState::ON);
}
@@ -463,7 +463,7 @@ BaseCPU::schedulePowerGatingEvent()
return;
}
if (ClockedObject::pwrState() == Enums::PwrState::CLK_GATED &&
if (powerState->get() == Enums::PwrState::CLK_GATED &&
powerGatingOnIdle) {
assert(!enterPwrGatingEvent.scheduled());
// Schedule a power gating event when clock gated for the specified
@@ -492,7 +492,7 @@ BaseCPU::activateContext(ThreadID thread_num)
if (enterPwrGatingEvent.scheduled())
deschedule(enterPwrGatingEvent);
// For any active thread running, update CPU power state to active (ON)
ClockedObject::pwrState(Enums::PwrState::ON);
powerState->set(Enums::PwrState::ON);
updateCycleCounters(CPU_STATE_WAKEUP);
}
@@ -513,7 +513,7 @@ BaseCPU::suspendContext(ThreadID thread_num)
updateCycleCounters(CPU_STATE_SLEEP);
// All CPU threads suspended, enter lower power state for the CPU
ClockedObject::pwrState(Enums::PwrState::CLK_GATED);
powerState->set(Enums::PwrState::CLK_GATED);
// If pwrGatingLatency is set to 0 then this mechanism is disabled
if (powerGatingOnIdle) {
@@ -532,7 +532,7 @@ BaseCPU::haltContext(ThreadID thread_num)
void
BaseCPU::enterPwrGating(void)
{
ClockedObject::pwrState(Enums::PwrState::OFF);
powerState->set(Enums::PwrState::OFF);
}
void
@@ -548,7 +548,7 @@ BaseCPU::switchOut()
flushTLBs();
// Go to the power gating state
ClockedObject::pwrState(Enums::PwrState::OFF);
powerState->set(Enums::PwrState::OFF);
}
void
@@ -561,7 +561,7 @@ BaseCPU::takeOverFrom(BaseCPU *oldCPU)
_pid = oldCPU->getPid();
_taskId = oldCPU->taskId();
// Take over the power state of the switchedOut CPU
ClockedObject::pwrState(oldCPU->pwrState());
powerState->set(oldCPU->powerState->get());
previousState = oldCPU->previousState;
previousCycle = oldCPU->previousCycle;

4
src/dev/arm/fvp_base_pwr_ctrl.cc
View File

@@ -280,7 +280,7 @@ FVPBasePwrCtrl::powerCoreOn(ThreadContext *const tc, PwrStatus *const pwrs)
npwrs->pc = 0;
}
}
tc->getCpuPtr()->pwrState(Enums::PwrState::ON);
tc->getCpuPtr()->powerState->set(Enums::PwrState::ON);
}
void
@@ -295,7 +295,7 @@ FVPBasePwrCtrl::powerCoreOff(ThreadContext *const tc, PwrStatus *const pwrs)
pwrs->pc = 0;
// Clear power-on reason
pwrs->wk = 0;
tc->getCpuPtr()->pwrState(Enums::PwrState::OFF);
tc->getCpuPtr()->powerState->set(Enums::PwrState::OFF);
}
void

29
src/sim/ClockedObject.py
View File

@@ -1,4 +1,4 @@
# Copyright (c) 2012, 2015-2016 ARM Limited
# Copyright (c) 2012, 2015-2017, 2019-2020 ARM Limited
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
@@ -33,28 +33,11 @@
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
from m5.objects.PowerState import PowerState
from m5.SimObject import SimObject
from m5.params import *
from m5.proxy import *
# Enumerate set of allowed power states that can be used by a clocked object.
# The list is kept generic to express a base minimal set.
# State definition :-
# Undefined: Invalid state, no power state derived information is available.
# On: The logic block is actively running and consuming dynamic and leakage
# energy depending on the amount of processing required.
# Clk_gated: The clock circuity within the block is gated to save dynamic
# energy, the power supply to the block is still on and leakage
# energy is being consumed by the block.
# Sram_retention: The SRAMs within the logic blocks are pulled into retention
# state to reduce leakage energy further.
# Off: The logic block is power gated and is not consuming any energy.
class PwrState(Enum): vals = ['UNDEFINED',
'ON',
'CLK_GATED',
'SRAM_RETENTION',
'OFF']
class ClockedObject(SimObject):
type = 'ClockedObject'
abstract = True
@@ -67,11 +50,5 @@ class ClockedObject(SimObject):
# Power model for this ClockedObject
power_model = VectorParam.PowerModel([], "Power models")
# Provide initial power state, should ideally get redefined in startup
# routine
default_p_state = Param.PwrState("UNDEFINED", "Default Power State")
power_state = Param.PowerState(PowerState(), "Power state")
p_state_clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
p_state_clk_gate_max = Param.Latency('1s',"Max value of the distribution")
p_state_clk_gate_bins = Param.Unsigned('20',
"# bins in clk gated distribution")

67
src/sim/PowerState.py Normal file
View File

@@ -0,0 +1,67 @@
# Copyright (c) 2012, 2015-2017 ARM Limited
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
# not be construed as granting a license to any other intellectual
# property including but not limited to intellectual property relating
# to a hardware implementation of the functionality of the software
# licensed hereunder. You may use the software subject to the license
# terms below provided that you ensure that this notice is replicated
# unmodified and in its entirety in all distributions of the software,
# modified or unmodified, in source code or in binary form.
#
# 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;
# neither the name of the copyright holders 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "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 THE COPYRIGHT
# OWNER OR CONTRIBUTORS 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.
#
from m5.SimObject import SimObject
from m5.params import *
from m5.proxy import *
# Enumerate set of allowed power states that can be used by a clocked object.
# The list is kept generic to express a base minimal set.
# State definition :-
# Undefined: Invalid state, no power state derived information is available.
# On: The logic block is actively running and consuming dynamic and leakage
# energy depending on the amount of processing required.
# Clk_gated: The clock circuity within the block is gated to save dynamic
# energy, the power supply to the block is still on and leakage
# energy is being consumed by the block.
# Sram_retention: The SRAMs within the logic blocks are pulled into retention
# state to reduce leakage energy further.
# Off: The logic block is power gated and is not consuming any energy.
class PwrState(Enum): vals = [
'UNDEFINED', 'ON', 'CLK_GATED', 'SRAM_RETENTION', 'OFF'
]
class PowerState(SimObject):
type = 'PowerState'
cxx_header = "sim/power_state.hh"
# Provide initial power state, should ideally get redefined in startup
# routine
default_state = Param.PwrState("UNDEFINED", "Default Power State")
clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
clk_gate_max = Param.Latency('1s',"Max value of the distribution")
clk_gate_bins = Param.Unsigned('20', "# bins in clk gated distribution")

2
src/sim/SConscript
View File

@@ -38,6 +38,7 @@ SimObject('System.py')
SimObject('DVFSHandler.py')
SimObject('SubSystem.py')
SimObject('RedirectPath.py')
SimObject('PowerState.py')
Source('async.cc')
Source('backtrace_%s.cc' % env['BACKTRACE_IMPL'])
@@ -75,6 +76,7 @@ Source('system.cc')
Source('dvfs_handler.cc')
Source('clocked_object.cc')
Source('mathexpr.cc')
Source('power_state.cc')
GTest('byteswap.test', 'byteswap.test.cc', '../base/types.cc')
GTest('guest_abi.test', 'guest_abi.test.cc')

154
src/sim/clocked_object.cc
View File

@@ -1,5 +1,5 @@
/*
* Copyright (c) 2015-2016 ARM Limited
* Copyright (c) 2015-2017, 2019-2020 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
@@ -41,12 +41,13 @@
#include "sim/power/power_model.hh"
ClockedObject::ClockedObject(const ClockedObjectParams *p) :
SimObject(p), Clocked(*p->clk_domain),
_currPwrState(p->default_p_state),
prvEvalTick(0),
stats(*this)
SimObject(p), Clocked(*p->clk_domain), powerState(p->power_state)
{
// Register the power_model with the object
// Slightly counter-intuitively, power models need to to register with the
// clocked object and not the power stated object because the power model
// needs information from the clock domain, which is an attribute of the
// clocked object.
for (auto & power_model: p->power_model)
power_model->setClockedObject(this);
}
@@ -54,149 +55,10 @@ ClockedObject::ClockedObject(const ClockedObjectParams *p) :
void
ClockedObject::serialize(CheckpointOut &cp) const
{
unsigned int currPwrState = (unsigned int)_currPwrState;
SERIALIZE_SCALAR(currPwrState);
SERIALIZE_SCALAR(prvEvalTick);
powerState->serialize(cp);
}
void
ClockedObject::unserialize(CheckpointIn &cp)
{
unsigned int currPwrState;
UNSERIALIZE_SCALAR(currPwrState);
UNSERIALIZE_SCALAR(prvEvalTick);
_currPwrState = Enums::PwrState(currPwrState);
}
void
ClockedObject::pwrState(Enums::PwrState p)
{
// Function should ideally be called only when there is a state change
if (_currPwrState == p) {
warn_once("ClockedObject: Already in the requested power state, " \
"request ignored");
return;
}
// No need to compute stats if in the same tick, update state though. This
// can happen in cases like a) during start of the simulation multiple
// state changes happens in init/startup phase, b) one takes a decision to
// migrate state but decides to reverts back to the original state in the
// same tick if other conditions are not met elsewhere.
// Any state change related stats would have been recorded on previous call
// to the pwrState() function.
if (prvEvalTick == curTick() && curTick() != 0) {
warn("ClockedObject %s: More than one power state change request "\
"encountered within the same simulation tick %d",
name(), prvEvalTick);
_currPwrState = p;
return;
}
// Record stats for previous state.
computeStats();
_currPwrState = p;
stats.numPwrStateTransitions++;
}
void
ClockedObject::computeStats()
{
// Calculate time elapsed from last (valid) state change
Tick elapsed_time = curTick() - prvEvalTick;
stats.pwrStateResidencyTicks[_currPwrState] += elapsed_time;
// Time spent in CLK_GATED state, this might change depending on
// transition to other low power states in respective simulation
// objects.
if (_currPwrState == Enums::PwrState::CLK_GATED) {
stats.pwrStateClkGateDist.sample(elapsed_time);
}
prvEvalTick = curTick();
}
std::vector<double>
ClockedObject::pwrStateWeights() const
{
// Get residency stats
std::vector<double> ret;
Stats::VCounter residencies;
stats.pwrStateResidencyTicks.value(residencies);
// Account for current state too!
Tick elapsed_time = curTick() - prvEvalTick;
residencies[_currPwrState] += elapsed_time;
ret.resize(Enums::PwrState::Num_PwrState);
for (unsigned i = 0; i < Enums::PwrState::Num_PwrState; i++)
ret[i] = residencies[i] / \
(stats.pwrStateResidencyTicks.total() + elapsed_time);
return ret;
}
ClockedObject::ClockedObjectStats::ClockedObjectStats(ClockedObject &co)
: Stats::Group(&co),
clockedObject(co),
ADD_STAT(numPwrStateTransitions,
"Number of power state transitions"),
ADD_STAT(pwrStateClkGateDist,
"Distribution of time spent in the clock gated state"),
ADD_STAT(pwrStateResidencyTicks,
"Cumulative time (in ticks) in various power states")
{
}
void
ClockedObject::ClockedObjectStats::regStats()
{
Stats::Group::regStats();
using namespace Stats;
const ClockedObjectParams *p = clockedObject.params();
numPwrStateTransitions.flags(nozero);
// Each sample is time in ticks
unsigned num_bins = std::max(p->p_state_clk_gate_bins, 10U);
pwrStateClkGateDist
.init(p->p_state_clk_gate_min, p->p_state_clk_gate_max,
(p->p_state_clk_gate_max / num_bins))
.flags(pdf | nozero | nonan)
;
pwrStateResidencyTicks
.init(Enums::PwrState::Num_PwrState)
.flags(nozero)
;
for (int i = 0; i < Enums::PwrState::Num_PwrState; i++) {
pwrStateResidencyTicks.subname(i, Enums::PwrStateStrings[i]);
}
numPwrStateTransitions = 0;
}
void
ClockedObject::ClockedObjectStats::preDumpStats()
{
Stats::Group::preDumpStats();
/**
* For every stats dump, the power state residency and other distribution
* stats should be computed just before the dump to ensure correct stats
* value being reported for current dump window. It avoids things like
* having any unreported time spent in a power state to be forwarded to the
* next dump window which might have rather unpleasant effects (like
* perturbing the distribution stats).
*/
clockedObject.computeStats();
powerState->unserialize(cp);
}

48
src/sim/clocked_object.hh
View File

@@ -1,5 +1,5 @@
/*
* Copyright (c) 2012-2013, 2015-2016 ARM Limited
* Copyright (c) 2012-2013, 2015-2017, 2019-2020 ARM Limited
* Copyright (c) 2013 Cornell University
* All rights reserved
*
@@ -44,12 +44,11 @@
#ifndef __SIM_CLOCKED_OBJECT_HH__
#define __SIM_CLOCKED_OBJECT_HH__
#include "base/callback.hh"
#include "base/intmath.hh"
#include "enums/PwrState.hh"
#include "params/ClockedObject.hh"
#include "sim/core.hh"
#include "sim/clock_domain.hh"
#include "sim/power_state.hh"
#include "sim/sim_object.hh"
/**
@@ -245,46 +244,7 @@ class ClockedObject : public SimObject, public Clocked
void serialize(CheckpointOut &cp) const override;
void unserialize(CheckpointIn &cp) override;
Enums::PwrState pwrState() const { return _currPwrState; }
std::string
pwrStateName() const
{
return Enums::PwrStateStrings[_currPwrState];
}
/** Returns the percentage residency for each power state */
std::vector<double> pwrStateWeights() const;
/**
* Record stats values like state residency by computing the time
* difference from previous update. Also, updates the previous evaluation
* tick once all stats are recorded.
* Usually called on power state change and stats dump callback.
*/
void computeStats();
void pwrState(Enums::PwrState);
protected:
/** To keep track of the current power state */
Enums::PwrState _currPwrState;
Tick prvEvalTick;
struct ClockedObjectStats : public Stats::Group
{
ClockedObjectStats(ClockedObject &co);
void regStats() override;
void preDumpStats() override;
ClockedObject &clockedObject;
Stats::Scalar numPwrStateTransitions;
Stats::Distribution pwrStateClkGateDist;
Stats::Vector pwrStateResidencyTicks;
} stats;
PowerState *powerState;
};
#endif //__SIM_CLOCKED_OBJECT_HH__

4
src/sim/power/power_model.cc
View File

@@ -102,7 +102,7 @@ PowerModel::getDynamicPower() const
// This power model only collects static data
return 0;
}
std::vector<double> w = clocked_object->pwrStateWeights();
std::vector<double> w = clocked_object->powerState->getWeights();
// Same number of states (excluding UNDEFINED)
assert(w.size() - 1 == states_pm.size());
@@ -124,7 +124,7 @@ PowerModel::getStaticPower() const
{
assert(clocked_object);
std::vector<double> w = clocked_object->pwrStateWeights();
std::vector<double> w = clocked_object->powerState->getWeights();
if (power_model_type == Enums::PMType::Dynamic) {
// This power model only collects dynamic data

200
src/sim/power_state.cc Normal file
View File

@@ -0,0 +1,200 @@
/*
* Copyright (c) 2015-2017, 2019-2020 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* 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;
* neither the name of the copyright holders 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE COPYRIGHT
* OWNER OR CONTRIBUTORS 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 "sim/power_state.hh"
#include "base/logging.hh"
PowerState::PowerState(const PowerStateParams *p) :
SimObject(p), _currState(p->default_state),
stats(*this)
{
}
void
PowerState::serialize(CheckpointOut &cp) const
{
unsigned int currState = (unsigned int)_currState;
SERIALIZE_SCALAR(currState);
SERIALIZE_SCALAR(prvEvalTick);
}
void
PowerState::unserialize(CheckpointIn &cp)
{
unsigned int currState;
UNSERIALIZE_SCALAR(currState);
UNSERIALIZE_SCALAR(prvEvalTick);
_currState = Enums::PwrState(currState);
}
void
PowerState::set(Enums::PwrState p)
{
// Function should ideally be called only when there is a state change
if (_currState == p) {
warn_once("PowerState: Already in the requested power state, "
"request ignored");
return;
}
// No need to compute stats if in the same tick, update state though. This
// can happen in cases like a) during start of the simulation multiple
// state changes happens in init/startup phase, b) one takes a decision to
// migrate state but decides to reverts back to the original state in the
// same tick if other conditions are not met elsewhere.
// Any state change related stats would have been recorded on previous call
// to this function.
if (prvEvalTick == curTick() && curTick() != 0) {
warn("PowerState: More than one power state change request "
"encountered within the same simulation tick");
_currState = p;
return;
}
// Record stats for previous state.
computeStats();
_currState = p;
stats.numTransitions++;
}
void
PowerState::computeStats()
{
// Calculate time elapsed from last (valid) state change
Tick elapsed_time = curTick() - prvEvalTick;
stats.pwrStateResidencyTicks[_currState] += elapsed_time;
// Time spent in CLK_GATED state, this might change depending on
// transition to other low power states in respective simulation
// objects.
if (_currState == Enums::PwrState::CLK_GATED) {
stats.ticksClkGated.sample(elapsed_time);
}
prvEvalTick = curTick();
}
std::vector<double>
PowerState::getWeights() const
{
// Get residency stats
std::vector<double> ret;
Stats::VCounter residencies;
stats.pwrStateResidencyTicks.value(residencies);
// Account for current state too!
Tick elapsed_time = curTick() - prvEvalTick;
residencies[_currState] += elapsed_time;
ret.resize(Enums::PwrState::Num_PwrState);
for (unsigned i = 0; i < Enums::PwrState::Num_PwrState; i++)
ret[i] = residencies[i] / \
(stats.pwrStateResidencyTicks.total() + elapsed_time);
return ret;
}
PowerState::PowerStateStats::PowerStateStats(PowerState &co)
: Stats::Group(&co),
powerState(co),
ADD_STAT(numTransitions,
"Number of power state transitions"),
ADD_STAT(ticksClkGated,
"Distribution of time spent in the clock gated state"),
ADD_STAT(pwrStateResidencyTicks,
"Cumulative time (in ticks) in various power states")
{
}
void
PowerState::PowerStateStats::regStats()
{
Stats::Group::regStats();
using namespace Stats;
const PowerStateParams *p = powerState.params();
numTransitions.flags(nozero);
// Each sample is time in ticks
unsigned num_bins = std::max(p->clk_gate_bins, 10U);
ticksClkGated
.init(p->clk_gate_min, p->clk_gate_max,
(p->clk_gate_max / num_bins))
.flags(pdf | nozero | nonan)
;
pwrStateResidencyTicks
.init(Enums::PwrState::Num_PwrState)
.flags(nozero)
;
for (int i = 0; i < Enums::PwrState::Num_PwrState; i++) {
pwrStateResidencyTicks.subname(i, Enums::PwrStateStrings[i]);
}
numTransitions = 0;
}
void
PowerState::PowerStateStats::preDumpStats()
{
Stats::Group::preDumpStats();
/**
* For every stats dump, the power state residency and other distribution
* stats should be computed just before the dump to ensure correct stats
* value being reported for current dump window. It avoids things like
* having any unreported time spent in a power state to be forwarded to the
* next dump window which might have rather unpleasant effects (like
* perturbing the distribution stats).
*/
powerState.computeStats();
}
PowerState*
PowerStateParams::create()
{
return new PowerState(this);
}

133
src/sim/power_state.hh Normal file
View File

@@ -0,0 +1,133 @@
/*
* Copyright (c) 2015-2017, 2020 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* 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;
* neither the name of the copyright holders 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE COPYRIGHT
* OWNER OR CONTRIBUTORS 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.
*/
/**
* @file
* PowerState declaration and implementation.
*/
#ifndef __SIM_POWER_STATE_HH__
#define __SIM_POWER_STATE_HH__
#include <set>
#include "base/callback.hh"
#include "base/statistics.hh"
#include "enums/PwrState.hh"
#include "params/PowerState.hh"
#include "sim/core.hh"
#include "sim/sim_object.hh"
/**
* Helper class for objects that have power states. This class provides the
* basic functionality to change between power states.
*/
class PowerState : public SimObject
{
public:
PowerState(const PowerStateParams *p);
/** Parameters of PowerState object */
typedef PowerStateParams Params;
const Params* params() const
{
return reinterpret_cast<const Params*>(_params);
}
void serialize(CheckpointOut &cp) const override;
void unserialize(CheckpointIn &cp) override;
/**
* Change the power state of this object to the power state p
*/
void set(Enums::PwrState p);
inline Enums::PwrState get() const
{
return _currState;
}
inline std::string getName() const
{
return Enums::PwrStateStrings[_currState];
}
/** Returns the percentage residency for each power state */
std::vector<double> getWeights() const;
/**
* Record stats values like state residency by computing the time
* difference from previous update. Also, updates the previous evaluation
* tick once all stats are recorded.
* Usually called on power state change and stats dump callback.
*/
void computeStats();
protected:
/** To keep track of the current power state */
Enums::PwrState _currState;
/** Last tick the power stats were calculated */
Tick prvEvalTick = 0;
struct PowerStateStats : public Stats::Group
{
PowerStateStats(PowerState &ps);
void regStats() override;
void preDumpStats() override;
PowerState &powerState;
Stats::Scalar numTransitions;
Stats::Distribution ticksClkGated;
/** Tracks the time spent in each of the power states */
Stats::Vector pwrStateResidencyTicks;
} stats;
};
class PowerStateDumpCallback : public Callback
{
PowerState *co;
public:
PowerStateDumpCallback(PowerState *co_t) : co(co_t) {}
virtual void process() { co->computeStats(); };
};
#endif //__SIM_POWER_STATE_HH__