LUMIERA.clone/src/vault/gear/block-flow.hpp
Ichthyostega 533112a4b0 Block-Flow: provide specialised ctor notation
...now able to create instances for all the relevant Activity verbs
2023-07-07 03:41:30 +02:00

151 lines
4.3 KiB
C++

/*
BLOCK-FLOW.hpp - specialised custom allocator to manage scheduler data
Copyright (C) Lumiera.org
2023, Hermann Vosseler <Ichthyostega@web.de>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/** @file block-flow.hpp
** Memory management scheme for activities and parameter data passed through
** the Scheduler within the Lumiera render engine. While — conceptually — the
** intended render operations are described as connected activity terms, sent
** as messages through the scheduler, the actual implementation requires a fixed
** descriptor record sitting at a stable memory location while the computation
** is underway. Moreover, activities can spawn further activities, implying that
** activity descriptor records can emanate from multiple threads concurrently,
** and the duration to keep those descriptors in valid state is contingent.
** On the other hand, ongoing rendering produces a constant flow of further
** activities, necessitating timely clean-up of obsolete descriptors.
** Used memory should be recycled, calling for an arrangement of
** pooled allocation tiles, extending the underlying block
** allocation on increased throughput.
**
** @note currently this rather marks the intended memory management pattern,
** while the actual allocations are still performed on the heap.
** @see BlockFlow_test
** @see SchedulerUsage_test
** @see extent-family.hpp underlying allocation scheme
**
** @todo WIP-WIP-WIP 6/2023 »Playback Vertical Slice«
**
*/
#ifndef SRC_VAULT_GEAR_BLOCK_FLOW_H_
#define SRC_VAULT_GEAR_BLOCK_FLOW_H_
#include "vault/common.hpp"
#include "vault/gear/activity.hpp"
#include "vault/mem/extent-family.hpp"
//#include "lib/symbol.hpp"
#include "lib/time/timevalue.hpp"
#include "lib/nocopy.hpp"
//#include "lib/util.hpp"
//#include <string>
namespace vault{
namespace gear {
// using util::isnil;
// using std::string;
using lib::time::Time;
namespace {// hard-wired parametrisation
const size_t EPOCH_SIZ = 100;
const size_t ACTIVITIES_PER_FRAME = 10;
const size_t INITIAL_FRAMES = 50;
const size_t INITIAL_ALLOC = 1 + (INITIAL_FRAMES * ACTIVITIES_PER_FRAME) / EPOCH_SIZ;
using Allocator = mem::ExtentFamily<Activity, EPOCH_SIZ>;
}
/**
*
*/
class Epoch
: public Allocator::Extent
{
/// @warning will be faked, not constructed
Epoch() = delete;
public:
struct EpochGate
: Activity
{
EpochGate()
: Activity{int(0), Time::ANYTIME}
{
UNIMPLEMENTED ("initialise allocation usage marker to zero");
}
// default copyable
};
static Epoch&
implantInto (Allocator::Extent& rawStorage)
{
Epoch& target = static_cast<Epoch&> (rawStorage);
new(&target[0]) EpochGate{};
return target;
}
EpochGate&
gate()
{
return static_cast<EpochGate&> ((*this)[0]);
}
};
/**
* Basic (abstracted) view of...
*
* @see SchedulerCommutator
* @see BlockFlow_test
*/
class BlockFlow
: util::NonCopyable
{
Allocator alloc_;
public:
BlockFlow()
: alloc_{INITIAL_ALLOC}
{ }
Activity&
createActivity (Activity::Verb verb, Time deadline)
{
UNIMPLEMENTED ("place new allocation");
}
void
discardBefore (Time deadline)
{
UNIMPLEMENTED ("traverse oldest Epochs and discard obsoleted");
}
};
}} // namespace vault::gear
#endif /*SRC_VAULT_GEAR_BLOCK_FLOW_H_*/