/* -*- c++ -*- */
/*
* Copyright 2004 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio 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 3, or (at your option)
* any later version.
*
* GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "single_threaded_scheduler.h"
#include <gnuradio/block.h>
#include <gnuradio/block_detail.h>
#include <gnuradio/buffer.h>
#include <boost/thread.hpp>
#include <boost/format.hpp>
#include <iostream>
#include <limits>
#include <assert.h>
#include <stdio.h>
namespace gr {
// must be defined to either 0 or 1
#define ENABLE_LOGGING 0
#if (ENABLE_LOGGING)
#define LOG(x) do { x; } while(0)
#else
#define LOG(x) do {;} while(0)
#endif
static int which_scheduler = 0;
single_threaded_scheduler_sptr
make_single_threaded_scheduler(const std::vector<block_sptr> &blocks)
{
return single_threaded_scheduler_sptr
(new single_threaded_scheduler(blocks));
}
single_threaded_scheduler::single_threaded_scheduler(const std::vector<block_sptr> &blocks)
: d_blocks(blocks), d_enabled(true), d_log(0)
{
if(ENABLE_LOGGING) {
std::string name = str(boost::format("sst-%d.log") % which_scheduler++);
d_log = new std::ofstream(name.c_str());
*d_log << "single_threaded_scheduler: "
<< d_blocks.size ()
<< " blocks\n";
}
}
single_threaded_scheduler::~single_threaded_scheduler()
{
if(ENABLE_LOGGING)
delete d_log;
}
void
single_threaded_scheduler::run()
{
// d_enabled = true; // KLUDGE
main_loop ();
}
void
single_threaded_scheduler::stop()
{
if(0)
std::cout << "gr_singled_threaded_scheduler::stop() "
<< this << std::endl;
d_enabled = false;
}
inline static unsigned int
round_up(unsigned int n, unsigned int multiple)
{
return ((n + multiple - 1) / multiple) * multiple;
}
inline static unsigned int
round_down(unsigned int n, unsigned int multiple)
{
return (n / multiple) * multiple;
}
//
// Return minimum available write space in all our downstream
// buffers or -1 if we're output blocked and the output we're
// blocked on is done.
//
static int
min_available_space(block_detail *d, int output_multiple)
{
int min_space = std::numeric_limits<int>::max();
for(int i = 0; i < d->noutputs (); i++) {
int n = round_down (d->output(i)->space_available (), output_multiple);
if(n == 0) { // We're blocked on output.
if(d->output(i)->done()) { // Downstream is done, therefore we're done.
return -1;
}
return 0;
}
min_space = std::min (min_space, n);
}
return min_space;
}
void
single_threaded_scheduler::main_loop()
{
static const int DEFAULT_CAPACITY = 16;
int noutput_items;
gr_vector_int ninput_items_required(DEFAULT_CAPACITY);
gr_vector_int ninput_items(DEFAULT_CAPACITY);
gr_vector_const_void_star input_items(DEFAULT_CAPACITY);
gr_vector_void_star output_items(DEFAULT_CAPACITY);
unsigned int bi;
unsigned int nalive;
int max_items_avail;
bool made_progress_last_pass;
bool making_progress;
for(unsigned i = 0; i < d_blocks.size (); i++)
d_blocks[i]->detail()->set_done (false); // reset any done flags
for(unsigned i = 0; i < d_blocks.size (); i++) // enable any drivers, etc.
d_blocks[i]->start();
bi = 0;
made_progress_last_pass = true;
making_progress = false;
// Loop while there are still blocks alive
nalive = d_blocks.size ();
while(d_enabled && nalive > 0) {
if(boost::this_thread::interruption_requested())
break;
block *m = d_blocks[bi].get ();
block_detail *d = m->detail().get ();
LOG(*d_log << std::endl << m);
if(d->done ())
goto next_block;
if(d->source_p ()) {
// Invoke sources as a last resort. As long as the previous
// pass made progress, don't call a source.
if(made_progress_last_pass) {
LOG(*d_log << " Skipping source\n");
goto next_block;
}
ninput_items_required.resize (0);
ninput_items.resize (0);
input_items.resize (0);
output_items.resize (d->noutputs ());
// determine the minimum available output space
noutput_items = min_available_space (d, m->output_multiple ());
LOG(*d_log << " source\n noutput_items = " << noutput_items << std::endl);
if(noutput_items == -1) // we're done
goto were_done;
if(noutput_items == 0) { // we're output blocked
LOG(*d_log << " BLKD_OUT\n");
goto next_block;
}
goto setup_call_to_work; // jump to common code
}
else if(d->sink_p ()) {
ninput_items_required.resize (d->ninputs ());
ninput_items.resize (d->ninputs ());
input_items.resize (d->ninputs ());
output_items.resize (0);
LOG(*d_log << " sink\n");
max_items_avail = 0;
for(int i = 0; i < d->ninputs (); i++) {
ninput_items[i] = d->input(i)->items_available();
//if (ninput_items[i] == 0 && d->input(i)->done())
if(ninput_items[i] < m->output_multiple() && d->input(i)->done())
goto were_done;
max_items_avail = std::max (max_items_avail, ninput_items[i]);
}
// take a swag at how much output we can sink
noutput_items = (int) (max_items_avail * m->relative_rate ());
noutput_items = round_down (noutput_items, m->output_multiple ());
LOG(*d_log << " max_items_avail = " << max_items_avail << std::endl);
LOG(*d_log << " noutput_items = " << noutput_items << std::endl);
if(noutput_items == 0) { // we're blocked on input
LOG(*d_log << " BLKD_IN\n");
goto next_block;
}
goto try_again; // Jump to code shared with regular case.
}
else {
// do the regular thing
ninput_items_required.resize(d->ninputs ());
ninput_items.resize(d->ninputs ());
input_items.resize(d->ninputs ());
output_items.resize(d->noutputs ());
max_items_avail = 0;
for(int i = 0; i < d->ninputs (); i++) {
ninput_items[i] = d->input(i)->items_available ();
max_items_avail = std::max(max_items_avail, ninput_items[i]);
}
// determine the minimum available output space
noutput_items = min_available_space(d, m->output_multiple ());
if(ENABLE_LOGGING){
*d_log << " regular ";
if(m->relative_rate() >= 1.0)
*d_log << "1:" << m->relative_rate() << std::endl;
else
*d_log << 1.0/m->relative_rate() << ":1\n";
*d_log << " max_items_avail = " << max_items_avail << std::endl;
*d_log << " noutput_items = " << noutput_items << std::endl;
}
if(noutput_items == -1) // we're done
goto were_done;
if(noutput_items == 0) { // we're output blocked
LOG(*d_log << " BLKD_OUT\n");
goto next_block;
}
#if 0
// Compute best estimate of noutput_items that we can really use.
noutput_items =
std::min((unsigned)noutput_items,
std::max((unsigned)m->output_multiple(),
round_up((unsigned)(max_items_avail * m->relative_rate()),
m->output_multiple())));
LOG(*d_log << " revised noutput_items = " << noutput_items << std::endl);
#endif
try_again:
if(m->fixed_rate()) {
// try to work it forward starting with max_items_avail.
// We want to try to consume all the input we've got.
int reqd_noutput_items = m->fixed_rate_ninput_to_noutput(max_items_avail);
reqd_noutput_items = round_up(reqd_noutput_items, m->output_multiple());
if(reqd_noutput_items > 0 && reqd_noutput_items <= noutput_items)
noutput_items = reqd_noutput_items;
}
// ask the block how much input they need to produce noutput_items
m->forecast(noutput_items, ninput_items_required);
// See if we've got sufficient input available
int i;
for(i = 0; i < d->ninputs (); i++)
if(ninput_items_required[i] > ninput_items[i]) // not enough
break;
if(i < d->ninputs()) { // not enough input on input[i]
// if we can, try reducing the size of our output request
if(noutput_items > m->output_multiple ()){
noutput_items /= 2;
noutput_items = round_up (noutput_items, m->output_multiple ());
goto try_again;
}
// We're blocked on input
LOG(*d_log << " BLKD_IN\n");
if(d->input(i)->done()) // If the upstream block is done, we're done
goto were_done;
// Is it possible to ever fulfill this request?
if(ninput_items_required[i] > d->input(i)->max_possible_items_available ()) {
// Nope, never going to happen...
std::cerr << "\nsched: <block " << m->name()
<< " (" << m->unique_id() << ")>"
<< " is requesting more input data\n"
<< " than we can provide.\n"
<< " ninput_items_required = "
<< ninput_items_required[i] << "\n"
<< " max_possible_items_available = "
<< d->input(i)->max_possible_items_available() << "\n"
<< " If this is a filter, consider reducing the number of taps.\n";
goto were_done;
}
goto next_block;
}
// We've got enough data on each input to produce noutput_items.
// Finish setting up the call to work.
for(int i = 0; i < d->ninputs (); i++)
input_items[i] = d->input(i)->read_pointer();
setup_call_to_work:
for(int i = 0; i < d->noutputs (); i++)
output_items[i] = d->output(i)->write_pointer();
// Do the actual work of the block
int n = m->general_work(noutput_items, ninput_items,
input_items, output_items);
LOG(*d_log << " general_work: noutput_items = " << noutput_items
<< " result = " << n << std::endl);
if(n == -1) // block is done
goto were_done;
d->produce_each(n); // advance write pointers
if(n > 0)
making_progress = true;
goto next_block;
}
assert(0);
were_done:
LOG(*d_log << " were_done\n");
d->set_done (true);
nalive--;
next_block:
if(++bi >= d_blocks.size ()) {
bi = 0;
made_progress_last_pass = making_progress;
making_progress = false;
}
}
for(unsigned i = 0; i < d_blocks.size(); i++) // disable any drivers, etc.
d_blocks[i]->stop();
}
} /* namespace gr */