mirror of
https://github.com/Atmosphere-NX/Atmosphere.git
synced 2024-11-15 00:16:48 +00:00
120 lines
4.4 KiB
C++
120 lines
4.4 KiB
C++
/*
|
|
* Copyright (c) Atmosphère-NX
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
#include <stratosphere.hpp>
|
|
|
|
namespace ams::os {
|
|
|
|
namespace {
|
|
|
|
ALWAYS_INLINE bool IsBarrierInitialized(const BarrierType *barrier) {
|
|
return barrier->max_threads != 0;
|
|
}
|
|
|
|
ALWAYS_INLINE u64 GetBarrierBaseCounterImpl(const BarrierType *barrier) {
|
|
/* Check pre-conditions. */
|
|
#if defined(AMS_OS_INTERNAL_CRITICAL_SECTION_IMPL_CAN_CHECK_LOCKED_BY_CURRENT_THREAD)
|
|
AMS_ASSERT(util::GetReference(barrier->cs_barrier).IsLockedByCurrentThread());
|
|
#endif
|
|
|
|
/* Convert two u32s to u64. */
|
|
return (static_cast<u64>(barrier->base_counter_lower) << 0) | (static_cast<u64>(barrier->base_counter_upper) << BITSIZEOF(barrier->base_counter_lower));
|
|
}
|
|
|
|
ALWAYS_INLINE void SetBarrierBaseCounterImpl(BarrierType *barrier, u64 value) {
|
|
/* Check pre-conditions. */
|
|
#if defined(AMS_OS_INTERNAL_CRITICAL_SECTION_IMPL_CAN_CHECK_LOCKED_BY_CURRENT_THREAD)
|
|
AMS_ASSERT(util::GetReference(barrier->cs_barrier).IsLockedByCurrentThread());
|
|
#endif
|
|
|
|
/* Store as two u32s. */
|
|
barrier->base_counter_lower = static_cast<u32>(value >> 0);
|
|
barrier->base_counter_upper = static_cast<u32>(value >> BITSIZEOF(barrier->base_counter_lower));
|
|
}
|
|
|
|
}
|
|
|
|
void InitializeBarrier(BarrierType *barrier, int num_threads) {
|
|
/* Check pre-conditions. */
|
|
AMS_ASSERT(num_threads >= 1);
|
|
|
|
/* Construct objects. */
|
|
util::ConstructAt(barrier->cs_barrier);
|
|
util::ConstructAt(barrier->cv_gathered);
|
|
|
|
/* Set member variables. */
|
|
barrier->max_threads = num_threads;
|
|
barrier->waiting_threads = 0;
|
|
barrier->base_counter_lower = 0;
|
|
barrier->base_counter_upper = 0;
|
|
}
|
|
|
|
void FinalizeBarrier(BarrierType *barrier) {
|
|
/* Check pre-conditions. */
|
|
AMS_ASSERT(IsBarrierInitialized(barrier));
|
|
AMS_ASSERT(barrier->waiting_threads == 0);
|
|
|
|
/* Clear max threads. */
|
|
barrier->max_threads = 0;
|
|
|
|
/* Destroy objects. */
|
|
util::DestroyAt(barrier->cs_barrier);
|
|
util::DestroyAt(barrier->cv_gathered);
|
|
}
|
|
|
|
void AwaitBarrier(BarrierType *barrier) {
|
|
/* Check pre-conditions. */
|
|
AMS_ASSERT(IsBarrierInitialized(barrier));
|
|
|
|
/* Await the barrier. */
|
|
{
|
|
/* Acquire exclusive access to the barrier. */
|
|
auto &cs = util::GetReference(barrier->cs_barrier);
|
|
std::scoped_lock lk(cs);
|
|
|
|
/* Read barrier state. */
|
|
const u64 base_counter = GetBarrierBaseCounterImpl(barrier);
|
|
const auto max_threads = barrier->max_threads;
|
|
auto waiting_threads = barrier->waiting_threads;
|
|
|
|
/* Determine next base counter. */
|
|
const u64 done_base_counter = base_counter + max_threads;
|
|
|
|
/* Increment waiting threads. */
|
|
++waiting_threads;
|
|
|
|
/* Check if all threads have synchronized. */
|
|
if (waiting_threads >= max_threads) {
|
|
/* They have, so reset waiting thread count. */
|
|
barrier->waiting_threads = 0;
|
|
|
|
/* Set the updated base counter. */
|
|
SetBarrierBaseCounterImpl(barrier, done_base_counter);
|
|
|
|
/* Broadcast to our cv. */
|
|
util::GetReference(barrier->cv_gathered).Broadcast();
|
|
} else {
|
|
/* More threads are needed, so update waiting thread count. */
|
|
barrier->waiting_threads = waiting_threads;
|
|
|
|
/* Wait for remaining threads to await. */
|
|
while (GetBarrierBaseCounterImpl(barrier) < done_base_counter) {
|
|
util::GetReference(barrier->cv_gathered).Wait(std::addressof(cs));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|