use cv in thread, move barrier to blt

thread
Brett 2024-07-14 14:08:39 -04:00
parent f7f63f6f84
commit 5b6924574a
5 changed files with 12 additions and 84 deletions

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@ -1,5 +1,5 @@
cmake_minimum_required(VERSION 3.25)
project(blt-gp VERSION 0.0.75)
project(blt-gp VERSION 0.0.76)
include(CTest)

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@ -41,6 +41,7 @@
#include <blt/std/types.h>
#include <blt/std/utility.h>
#include <blt/std/memory.h>
#include <blt/std/thread.h>
#include <blt/gp/fwdecl.h>
#include <blt/gp/typesystem.h>
#include <blt/gp/operations.h>
@ -54,79 +55,6 @@
namespace blt::gp
{
namespace detail
{
// Author: Kirk Saunders (ks825016@ohio.edu)
// Description: Simple implementation of a thread barrier
// using C++ condition variables.
// Date: 2/17/2020
// https://github.com/kirksaunders/barrier/blob/master/barrier.hpp
class barrier
{
public:
// Construct barrier for use with num threads.
explicit barrier(std::atomic_bool& exit_cond, std::size_t num)
: num_threads(num),
wait_count(0),
instance(0),
mut(),
cv(),
exit_cond(exit_cond)
{
if (num == 0)
{
throw std::invalid_argument("Barrier thread count cannot be 0");
}
}
// disable copying of barrier
barrier(const barrier&) = delete;
barrier& operator=(const barrier&) = delete;
// This function blocks the calling thread until
// all threads (specified by num_threads) have
// called it. Blocking is achieved using a
// call to condition_variable.wait().
void wait()
{
std::unique_lock<std::mutex> lock(mut); // acquire lock
std::size_t inst = instance; // store current instance for comparison
// in predicate
if (++wait_count == num_threads)
{ // all threads reached barrier
wait_count = 0; // reset wait_count
instance++; // increment instance for next use of barrier and to
// pass condition variable predicate
cv.notify_all();
} else
{ // not all threads have reached barrier
cv.wait(lock, [this, &inst]() { return (instance != inst || exit_cond); });
// NOTE: The predicate lambda here protects against spurious
// wakeups of the thread. As long as this->instance is
// equal to inst, the thread will not wake.
// this->instance will only increment when all threads
// have reached the barrier and are ready to be unblocked.
}
}
void notify_all()
{
cv.notify_all();
}
private:
std::size_t num_threads; // number of threads using barrier
std::size_t wait_count; // counter to keep track of waiting threads
std::size_t instance; // counter to keep track of barrier use count
std::mutex mut; // mutex used to protect resources
std::condition_variable cv; // condition variable used to block threads
std::atomic_bool& exit_cond; // used to signal we should exit
};
}
struct argc_t
{
blt::u32 argc = 0;
@ -420,6 +348,7 @@ namespace blt::gp
}
thread_helper.barrier.wait();
});
thread_helper.thread_function_condition.notify_all();
}
evaluate_fitness_internal();
}
@ -585,13 +514,16 @@ namespace blt::gp
struct concurrency_storage
{
std::vector<std::unique_ptr<std::thread>> threads;
std::mutex thread_function_control;
std::condition_variable thread_function_condition {};
std::atomic_uint64_t evaluation_left = 0;
std::atomic_bool lifetime_over = false;
detail::barrier barrier;
blt::barrier barrier;
explicit concurrency_storage(blt::size_t threads): barrier(lifetime_over, threads)
explicit concurrency_storage(blt::size_t threads): barrier(threads, lifetime_over)
{}
} thread_helper{config.threads};

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@ -75,11 +75,8 @@ namespace blt::gp
}
for (blt::size_t i = 0; i < config.elites; i++)
{
// BLT_DEBUG("%lf at %ld", values[i].second, values[i].first);
next_pop.get_individuals().push_back(current_pop.get_individuals()[values[i].first]);
}
}
while (next_pop.get_individuals().size() < config.population_size)
{

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@ -63,14 +63,12 @@ namespace blt::gp
{
if (execution_function == nullptr)
{
std::scoped_lock lock(thread_helper.thread_function_control);
if (thread_execution_service != nullptr)
std::unique_lock lock(thread_helper.thread_function_control);
thread_helper.thread_function_condition.wait(lock, [this]() { return thread_execution_service != nullptr; });
execution_function = thread_execution_service.load(std::memory_order_acquire);
std::cout.flush();
}
if (execution_function != nullptr)
(*execution_function)(i);
std::this_thread::sleep_for(std::chrono::milliseconds(1));
}
}));
}

1
test_perf_clang.sh Executable file
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@ -0,0 +1 @@
perf stat -d -d -d -r 30 -e branches,branch-misses,cache-misses,cache-references,cycles,instructions,alignment-faults,cgroup-switches,faults,duration_time,user_time,system_time,L1-dcache-loads,L1-dcache-load-misses,L1-dcache-prefetches,L1-icache-loads,L1-icache-load-misses,dTLB-loads,dTLB-load-misses,iTLB-loads,iTLB-load-misses,l2_request_g1.all_no_prefetch,page-faults,page-faults:u,page-faults:k ./cmake-build-release-clang/blt-SR-playground-example