diff --git a/src/citra_qt/debugger/wait_tree.cpp b/src/citra_qt/debugger/wait_tree.cpp
index 51e70fae3..5a308bf7f 100644
--- a/src/citra_qt/debugger/wait_tree.cpp
+++ b/src/citra_qt/debugger/wait_tree.cpp
@@ -229,7 +229,8 @@ std::vector<std::unique_ptr<WaitTreeItem>> WaitTreeThread::GetChildren() const {
list.push_back(std::make_unique<WaitTreeMutexList>(thread.held_mutexes));
}
if (thread.status == THREADSTATUS_WAIT_SYNCH) {
- list.push_back(std::make_unique<WaitTreeObjectList>(thread.wait_objects, thread.wait_all));
+ list.push_back(std::make_unique<WaitTreeObjectList>(thread.wait_objects,
+ thread.IsSleepingOnWaitAll()));
}
return list;
diff --git a/src/core/hle/kernel/address_arbiter.cpp b/src/core/hle/kernel/address_arbiter.cpp
index 37eec4c84..b5a0cc3a3 100644
--- a/src/core/hle/kernel/address_arbiter.cpp
+++ b/src/core/hle/kernel/address_arbiter.cpp
@@ -79,8 +79,6 @@ ResultCode AddressArbiter::ArbitrateAddress(ArbitrationType type, VAddr address,
ErrorSummary::WrongArgument, ErrorLevel::Usage);
}
- HLE::Reschedule(__func__);
-
// The calls that use a timeout seem to always return a Timeout error even if they did not put
// the thread to sleep
if (type == ArbitrationType::WaitIfLessThanWithTimeout ||
diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
index 0c8752670..209d35270 100644
--- a/src/core/hle/kernel/kernel.cpp
+++ b/src/core/hle/kernel/kernel.cpp
@@ -3,6 +3,7 @@
// Refer to the license.txt file included.
#include <algorithm>
+#include <boost/range/algorithm_ext/erase.hpp>
#include "common/assert.h"
#include "common/logging/log.h"
#include "core/hle/config_mem.h"
@@ -31,13 +32,60 @@ void WaitObject::RemoveWaitingThread(Thread* thread) {
waiting_threads.erase(itr);
}
-void WaitObject::WakeupAllWaitingThreads() {
- for (auto thread : waiting_threads)
- thread->ResumeFromWait();
+SharedPtr<Thread> WaitObject::GetHighestPriorityReadyThread() {
+ // Remove the threads that are ready or already running from our waitlist
+ boost::range::remove_erase_if(waiting_threads, [](const SharedPtr<Thread>& thread) {
+ return thread->status == THREADSTATUS_RUNNING || thread->status == THREADSTATUS_READY;
+ });
+
+ // TODO(Subv): This call should be performed inside the loop below to check if an object can be
+ // acquired by a particular thread. This is useful for things like recursive locking of Mutexes.
+ if (ShouldWait())
+ return nullptr;
+
+ Thread* candidate = nullptr;
+ s32 candidate_priority = THREADPRIO_LOWEST + 1;
+
+ for (const auto& thread : waiting_threads) {
+ if (thread->current_priority >= candidate_priority)
+ continue;
- waiting_threads.clear();
+ bool ready_to_run =
+ std::none_of(thread->wait_objects.begin(), thread->wait_objects.end(),
+ [](const SharedPtr<WaitObject>& object) { return object->ShouldWait(); });
+ if (ready_to_run) {
+ candidate = thread.get();
+ candidate_priority = thread->current_priority;
+ }
+ }
+
+ return candidate;
+}
- HLE::Reschedule(__func__);
+void WaitObject::WakeupAllWaitingThreads() {
+ while (auto thread = GetHighestPriorityReadyThread()) {
+ if (!thread->IsSleepingOnWaitAll()) {
+ Acquire();
+ // Set the output index of the WaitSynchronizationN call to the index of this object.
+ if (thread->wait_set_output) {
+ thread->SetWaitSynchronizationOutput(thread->GetWaitObjectIndex(this));
+ thread->wait_set_output = false;
+ }
+ } else {
+ for (auto& object : thread->wait_objects) {
+ object->Acquire();
+ object->RemoveWaitingThread(thread.get());
+ }
+ // Note: This case doesn't update the output index of WaitSynchronizationN.
+ // Clear the thread's waitlist
+ thread->wait_objects.clear();
+ }
+
+ thread->SetWaitSynchronizationResult(RESULT_SUCCESS);
+ thread->ResumeFromWait();
+ // Note: Removing the thread from the object's waitlist will be
+ // done by GetHighestPriorityReadyThread.
+ }
}
const std::vector<SharedPtr<Thread>>& WaitObject::GetWaitingThreads() const {
diff --git a/src/core/hle/kernel/kernel.h b/src/core/hle/kernel/kernel.h
index 0b811c5a7..1adcf6c71 100644
--- a/src/core/hle/kernel/kernel.h
+++ b/src/core/hle/kernel/kernel.h
@@ -151,9 +151,15 @@ public:
*/
void RemoveWaitingThread(Thread* thread);
- /// Wake up all threads waiting on this object
+ /**
+ * Wake up all threads waiting on this object that can be awoken, in priority order,
+ * and set the synchronization result and output of the thread.
+ */
void WakeupAllWaitingThreads();
+ /// Obtains the highest priority thread that is ready to run from this object's waiting list.
+ SharedPtr<Thread> GetHighestPriorityReadyThread();
+
/// Get a const reference to the waiting threads list for debug use
const std::vector<SharedPtr<Thread>>& GetWaitingThreads() const;
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index 84d6d24c6..4bbc08516 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -120,8 +120,6 @@ void Thread::Stop() {
u32 tls_slot =
((tls_address - Memory::TLS_AREA_VADDR) % Memory::PAGE_SIZE) / Memory::TLS_ENTRY_SIZE;
Kernel::g_current_process->tls_slots[tls_page].reset(tls_slot);
-
- HLE::Reschedule(__func__);
}
Thread* ArbitrateHighestPriorityThread(u32 address) {
@@ -180,50 +178,6 @@ static void PriorityBoostStarvedThreads() {
}
}
-/**
- * Gets the registers for timeout parameter of the next WaitSynchronization call.
- * @param thread a pointer to the thread that is ready to call WaitSynchronization
- * @returns a tuple of two register pointers to low and high part of the timeout parameter
- */
-static std::tuple<u32*, u32*> GetWaitSynchTimeoutParameterRegister(Thread* thread) {
- bool thumb_mode = (thread->context.cpsr & TBIT) != 0;
- u16 thumb_inst = Memory::Read16(thread->context.pc & 0xFFFFFFFE);
- u32 inst = Memory::Read32(thread->context.pc & 0xFFFFFFFC) & 0x0FFFFFFF;
-
- if ((thumb_mode && thumb_inst == 0xDF24) || (!thumb_mode && inst == 0x0F000024)) {
- // svc #0x24 (WaitSynchronization1)
- return std::make_tuple(&thread->context.cpu_registers[2],
- &thread->context.cpu_registers[3]);
- } else if ((thumb_mode && thumb_inst == 0xDF25) || (!thumb_mode && inst == 0x0F000025)) {
- // svc #0x25 (WaitSynchronizationN)
- return std::make_tuple(&thread->context.cpu_registers[0],
- &thread->context.cpu_registers[4]);
- }
-
- UNREACHABLE();
-}
-
-/**
- * Updates the WaitSynchronization timeout parameter according to the difference
- * between ticks of the last WaitSynchronization call and the incoming one.
- * @param timeout_low a pointer to the register for the low part of the timeout parameter
- * @param timeout_high a pointer to the register for the high part of the timeout parameter
- * @param last_tick tick of the last WaitSynchronization call
- */
-static void UpdateTimeoutParameter(u32* timeout_low, u32* timeout_high, u64 last_tick) {
- s64 timeout = ((s64)*timeout_high << 32) | *timeout_low;
-
- if (timeout != -1) {
- timeout -= cyclesToUs(CoreTiming::GetTicks() - last_tick) * 1000; // in nanoseconds
-
- if (timeout < 0)
- timeout = 0;
-
- *timeout_low = timeout & 0xFFFFFFFF;
- *timeout_high = timeout >> 32;
- }
-}
-
/**
* Switches the CPU's active thread context to that of the specified thread
* @param new_thread The thread to switch to
@@ -254,32 +208,6 @@ static void SwitchContext(Thread* new_thread) {
current_thread = new_thread;
- // If the thread was waited by a svcWaitSynch call, step back PC by one instruction to rerun
- // the SVC when the thread wakes up. This is necessary to ensure that the thread can acquire
- // the requested wait object(s) before continuing.
- if (new_thread->waitsynch_waited) {
- // CPSR flag indicates CPU mode
- bool thumb_mode = (new_thread->context.cpsr & TBIT) != 0;
-
- // SVC instruction is 2 bytes for THUMB, 4 bytes for ARM
- new_thread->context.pc -= thumb_mode ? 2 : 4;
-
- // Get the register for timeout parameter
- u32 *timeout_low, *timeout_high;
- std::tie(timeout_low, timeout_high) = GetWaitSynchTimeoutParameterRegister(new_thread);
-
- // Update the timeout parameter
- UpdateTimeoutParameter(timeout_low, timeout_high, new_thread->last_running_ticks);
- }
-
- // Clean up the thread's wait_objects, they'll be restored if needed during
- // the svcWaitSynchronization call
- for (size_t i = 0; i < new_thread->wait_objects.size(); ++i) {
- SharedPtr<WaitObject> object = new_thread->wait_objects[i];
- object->RemoveWaitingThread(new_thread);
- }
- new_thread->wait_objects.clear();
-
ready_queue.remove(new_thread->current_priority, new_thread);
new_thread->status = THREADSTATUS_RUNNING;
@@ -319,17 +247,13 @@ static Thread* PopNextReadyThread() {
void WaitCurrentThread_Sleep() {
Thread* thread = GetCurrentThread();
thread->status = THREADSTATUS_WAIT_SLEEP;
-
- HLE::Reschedule(__func__);
}
void WaitCurrentThread_WaitSynchronization(std::vector<SharedPtr<WaitObject>> wait_objects,
- bool wait_set_output, bool wait_all) {
+ bool wait_set_output) {
Thread* thread = GetCurrentThread();
thread->wait_set_output = wait_set_output;
- thread->wait_all = wait_all;
thread->wait_objects = std::move(wait_objects);
- thread->waitsynch_waited = true;
thread->status = THREADSTATUS_WAIT_SYNCH;
}
@@ -351,15 +275,15 @@ static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
return;
}
- thread->waitsynch_waited = false;
-
if (thread->status == THREADSTATUS_WAIT_SYNCH || thread->status == THREADSTATUS_WAIT_ARB) {
+ thread->wait_set_output = false;
+ // Remove the thread from each of its waiting objects' waitlists
+ for (auto& object : thread->wait_objects)
+ object->RemoveWaitingThread(thread.get());
+ thread->wait_objects.clear();
thread->SetWaitSynchronizationResult(ResultCode(ErrorDescription::Timeout, ErrorModule::OS,
ErrorSummary::StatusChanged,
ErrorLevel::Info));
-
- if (thread->wait_set_output)
- thread->SetWaitSynchronizationOutput(-1);
}
thread->ResumeFromWait();
@@ -399,6 +323,7 @@ void Thread::ResumeFromWait() {
ready_queue.push_back(current_priority, this);
status = THREADSTATUS_READY;
+ HLE::Reschedule(__func__);
}
/**
@@ -494,13 +419,11 @@ ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point,
thread->last_running_ticks = CoreTiming::GetTicks();
thread->processor_id = processor_id;
thread->wait_set_output = false;
- thread->wait_all = false;
thread->wait_objects.clear();
thread->wait_address = 0;
thread->name = std::move(name);
thread->callback_handle = wakeup_callback_handle_table.Create(thread).MoveFrom();
thread->owner_process = g_current_process;
- thread->waitsynch_waited = false;
// Find the next available TLS index, and mark it as used
auto& tls_slots = Kernel::g_current_process->tls_slots;
@@ -555,8 +478,6 @@ ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point,
ready_queue.push_back(thread->current_priority, thread.get());
thread->status = THREADSTATUS_READY;
- HLE::Reschedule(__func__);
-
return MakeResult<SharedPtr<Thread>>(std::move(thread));
}
@@ -619,14 +540,6 @@ void Reschedule() {
HLE::DoneRescheduling();
- // Don't bother switching to the same thread.
- // But if the thread was waiting on objects, we still need to switch it
- // to perform PC modification, change state to RUNNING, etc.
- // This occurs in the case when an object the thread is waiting on immediately wakes up
- // the current thread before Reschedule() is called.
- if (next == cur && (next == nullptr || next->waitsynch_waited == false))
- return;
-
if (cur && next) {
LOG_TRACE(Kernel, "context switch %u -> %u", cur->GetObjectId(), next->GetObjectId());
} else if (cur) {
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index e0ffcea8a..238359fc5 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -5,7 +5,9 @@
#pragma once
#include <string>
+#include <unordered_map>
#include <vector>
+#include <boost/container/flat_map.hpp>
#include <boost/container/flat_set.hpp>
#include "common/common_types.h"
#include "core/core.h"
@@ -124,6 +126,16 @@ public:
*/
void SetWaitSynchronizationOutput(s32 output);
+ /**
+ * Retrieves the index that this particular object occupies in the list of objects
+ * that the thread passed to WaitSynchronizationN.
+ * It is used to set the output value of WaitSynchronizationN when the thread is awakened.
+ * @param object Object to query the index of.
+ */
+ s32 GetWaitObjectIndex(const WaitObject* object) const {
+ return wait_objects_index.at(object->GetObjectId());
+ }
+
/**
* Stops a thread, invalidating it from further use
*/
@@ -137,6 +149,15 @@ public:
return tls_address;
}
+ /**
+ * Returns whether this thread is waiting for all the objects in
+ * its wait list to become ready, as a result of a WaitSynchronizationN call
+ * with wait_all = true, or a ReplyAndReceive call.
+ */
+ bool IsSleepingOnWaitAll() const {
+ return !wait_objects.empty();
+ }
+
Core::ThreadContext context;
u32 thread_id;
@@ -154,16 +175,22 @@ public:
VAddr tls_address; ///< Virtual address of the Thread Local Storage of the thread
- bool waitsynch_waited; ///< Set to true if the last svcWaitSynch call caused the thread to wait
-
/// Mutexes currently held by this thread, which will be released when it exits.
boost::container::flat_set<SharedPtr<Mutex>> held_mutexes;
- SharedPtr<Process> owner_process; ///< Process that owns this thread
- std::vector<SharedPtr<WaitObject>> wait_objects; ///< Objects that the thread is waiting on
- VAddr wait_address; ///< If waiting on an AddressArbiter, this is the arbitration address
- bool wait_all; ///< True if the thread is waiting on all objects before resuming
- bool wait_set_output; ///< True if the output parameter should be set on thread wakeup
+ SharedPtr<Process> owner_process; ///< Process that owns this thread
+
+ /// Objects that the thread is waiting on.
+ /// This is only populated when the thread should wait for all the objects to become ready.
+ std::vector<SharedPtr<WaitObject>> wait_objects;
+
+ /// Mapping of Object ids to their position in the last waitlist that this object waited on.
+ boost::container::flat_map<int, s32> wait_objects_index;
+
+ VAddr wait_address; ///< If waiting on an AddressArbiter, this is the arbitration address
+
+ /// True if the WaitSynchronizationN output parameter should be set on thread wakeup.
+ bool wait_set_output;
std::string name;
@@ -215,10 +242,9 @@ void WaitCurrentThread_Sleep();
* @param wait_objects Kernel objects that we are waiting on
* @param wait_set_output If true, set the output parameter on thread wakeup (for
* WaitSynchronizationN only)
- * @param wait_all If true, wait on all objects before resuming (for WaitSynchronizationN only)
*/
void WaitCurrentThread_WaitSynchronization(std::vector<SharedPtr<WaitObject>> wait_objects,
- bool wait_set_output, bool wait_all);
+ bool wait_set_output);
/**
* Waits the current thread from an ArbitrateAddress call
diff --git a/src/core/hle/kernel/timer.cpp b/src/core/hle/kernel/timer.cpp
index eac181f4e..b50cf520d 100644
--- a/src/core/hle/kernel/timer.cpp
+++ b/src/core/hle/kernel/timer.cpp
@@ -60,14 +60,10 @@ void Timer::Set(s64 initial, s64 interval) {
u64 initial_microseconds = initial / 1000;
CoreTiming::ScheduleEvent(usToCycles(initial_microseconds), timer_callback_event_type,
callback_handle);
-
- HLE::Reschedule(__func__);
}
void Timer::Cancel() {
CoreTiming::UnscheduleEvent(timer_callback_event_type, callback_handle);
-
- HLE::Reschedule(__func__);
}
void Timer::Clear() {
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index e5ba9a484..ef25acc4a 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -43,6 +43,9 @@ const ResultCode ERR_PORT_NAME_TOO_LONG(ErrorDescription(30), ErrorModule::OS,
ErrorSummary::InvalidArgument,
ErrorLevel::Usage); // 0xE0E0181E
+const ResultCode ERR_SYNC_TIMEOUT(ErrorDescription::Timeout, ErrorModule::OS,
+ ErrorSummary::StatusChanged, ErrorLevel::Info);
+
const ResultCode ERR_MISALIGNED_ADDRESS{// 0xE0E01BF1
ErrorDescription::MisalignedAddress, ErrorModule::OS,
ErrorSummary::InvalidArgument, ErrorLevel::Usage};
@@ -260,27 +263,30 @@ static ResultCode WaitSynchronization1(Handle handle, s64 nano_seconds) {
auto object = Kernel::g_handle_table.GetWaitObject(handle);
Kernel::Thread* thread = Kernel::GetCurrentThread();
- thread->waitsynch_waited = false;
-
if (object == nullptr)
return ERR_INVALID_HANDLE;
LOG_TRACE(Kernel_SVC, "called handle=0x%08X(%s:%s), nanoseconds=%lld", handle,
object->GetTypeName().c_str(), object->GetName().c_str(), nano_seconds);
- HLE::Reschedule(__func__);
-
- // Check for next thread to schedule
if (object->ShouldWait()) {
+ if (nano_seconds == 0)
+ return ERR_SYNC_TIMEOUT;
+
object->AddWaitingThread(thread);
- Kernel::WaitCurrentThread_WaitSynchronization({object}, false, false);
+ // TODO(Subv): Perform things like update the mutex lock owner's priority to
+ // prevent priority inversion. Currently this is done in Mutex::ShouldWait,
+ // but it should be moved to a function that is called from here.
+ thread->status = THREADSTATUS_WAIT_SYNCH;
// Create an event to wake the thread up after the specified nanosecond delay has passed
thread->WakeAfterDelay(nano_seconds);
- // NOTE: output of this SVC will be set later depending on how the thread resumes
- return HLE::RESULT_INVALID;
+ // Note: The output of this SVC will be set to RESULT_SUCCESS if the thread
+ // resumes due to a signal in its wait objects.
+ // Otherwise we retain the default value of timeout.
+ return ERR_SYNC_TIMEOUT;
}
object->Acquire();
@@ -291,11 +297,7 @@ static ResultCode WaitSynchronization1(Handle handle, s64 nano_seconds) {
/// Wait for the given handles to synchronize, timeout after the specified nanoseconds
static ResultCode WaitSynchronizationN(s32* out, Handle* handles, s32 handle_count, bool wait_all,
s64 nano_seconds) {
- bool wait_thread = !wait_all;
- int handle_index = 0;
Kernel::Thread* thread = Kernel::GetCurrentThread();
- bool was_waiting = thread->waitsynch_waited;
- thread->waitsynch_waited = false;
// Check if 'handles' is invalid
if (handles == nullptr)
@@ -311,90 +313,113 @@ static ResultCode WaitSynchronizationN(s32* out, Handle* handles, s32 handle_cou
return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS,
ErrorSummary::InvalidArgument, ErrorLevel::Usage);
- // If 'handle_count' is non-zero, iterate through each handle and wait the current thread if
- // necessary
- if (handle_count != 0) {
- bool selected = false; // True once an object has been selected
-
- Kernel::SharedPtr<Kernel::WaitObject> wait_object;
-
- for (int i = 0; i < handle_count; ++i) {
- auto object = Kernel::g_handle_table.GetWaitObject(handles[i]);
- if (object == nullptr)
- return ERR_INVALID_HANDLE;
-
- // Check if the current thread should wait on this object...
- if (object->ShouldWait()) {
-
- // Check we are waiting on all objects...
- if (wait_all)
- // Wait the thread
- wait_thread = true;
- } else {
- // Do not wait on this object, check if this object should be selected...
- if (!wait_all && (!selected || (wait_object == object && was_waiting))) {
- // Do not wait the thread
- wait_thread = false;
- handle_index = i;
- wait_object = object;
- selected = true;
- }
- }
- }
- } else {
- // If no handles were passed in, put the thread to sleep only when 'wait_all' is false
- // NOTE: This should deadlock the current thread if no timeout was specified
- if (!wait_all) {
- wait_thread = true;
- }
+ using ObjectPtr = Kernel::SharedPtr<Kernel::WaitObject>;
+ std::vector<ObjectPtr> objects(handle_count);
+
+ for (int i = 0; i < handle_count; ++i) {
+ auto object = Kernel::g_handle_table.GetWaitObject(handles[i]);
+ if (object == nullptr)
+ return ERR_INVALID_HANDLE;
+ objects[i] = object;
}
- SCOPE_EXIT({
- HLE::Reschedule("WaitSynchronizationN");
- }); // Reschedule after putting the threads to sleep.
+ // Clear the mapping of wait object indices.
+ // We don't want any lingering state in this map.
+ // It will be repopulated later in the wait_all = false case.
+ thread->wait_objects_index.clear();
+
+ if (wait_all) {
+ bool all_available =
+ std::all_of(objects.begin(), objects.end(),
+ [](const ObjectPtr& object) { return !object->ShouldWait(); });
+ if (all_available) {
+ // We can acquire all objects right now, do so.
+ for (auto& object : objects)
+ object->Acquire();
+ // Note: In this case, the `out` parameter is not set,
+ // and retains whatever value it had before.
+ return RESULT_SUCCESS;
+ }
+
+ // Not all objects were available right now, prepare to suspend the thread.
- // If thread should wait, then set its state to waiting
- if (wait_thread) {
+ // If a timeout value of 0 was provided, just return the Timeout error code instead of
+ // suspending the thread.
+ if (nano_seconds == 0)
+ return ERR_SYNC_TIMEOUT;
- // Actually wait the current thread on each object if we decided to wait...
- std::vector<SharedPtr<Kernel::WaitObject>> wait_objects;
- wait_objects.reserve(handle_count);
+ // Put the thread to sleep
+ thread->status = THREADSTATUS_WAIT_SYNCH;
- for (int i = 0; i < handle_count; ++i) {
- auto object = Kernel::g_handle_table.GetWaitObject(handles[i]);
- object->AddWaitingThread(Kernel::GetCurrentThread());
- wait_objects.push_back(object);
+ // Add the thread to each of the objects' waiting threads.
+ for (auto& object : objects) {
+ object->AddWaitingThread(thread);
+ // TODO(Subv): Perform things like update the mutex lock owner's priority to
+ // prevent priority inversion. Currently this is done in Mutex::ShouldWait,
+ // but it should be moved to a function that is called from here.
}
- Kernel::WaitCurrentThread_WaitSynchronization(std::move(wait_objects), true, wait_all);
+ // Set the thread's waitlist to the list of objects passed to WaitSynchronizationN
+ thread->wait_objects = std::move(objects);
// Create an event to wake the thread up after the specified nanosecond delay has passed
- Kernel::GetCurrentThread()->WakeAfterDelay(nano_seconds);
-
- // NOTE: output of this SVC will be set later depending on how the thread resumes
- return HLE::RESULT_INVALID;
- }
+ thread->WakeAfterDelay(nano_seconds);
- // Acquire objects if we did not wait...
- for (int i = 0; i < handle_count; ++i) {
- auto object = Kernel::g_handle_table.GetWaitObject(handles[i]);
+ // This value gets set to -1 by default in this case, it is not modified after this.
+ *out = -1;
+ // Note: The output of this SVC will be set to RESULT_SUCCESS if the thread resumes due to
+ // a signal in one of its wait objects.
+ return ERR_SYNC_TIMEOUT;
+ } else {
+ // Find the first object that is acquirable in the provided list of objects
+ auto itr = std::find_if(objects.begin(), objects.end(),
+ [](const ObjectPtr& object) { return !object->ShouldWait(); });
- // Acquire the object if it is not waiting...
- if (!object->ShouldWait()) {
+ if (itr != objects.end()) {
+ // We found a ready object, acquire it and set the result value
+ Kernel::WaitObject* object = itr->get();
object->Acquire();
+ *out = std::distance(objects.begin(), itr);
+ return RESULT_SUCCESS;
+ }
+
+ // No objects were ready to be acquired, prepare to suspend the thread.
+
+ // If a timeout value of 0 was provided, just return the Timeout error code instead of
+ // suspending the thread.
+ if (nano_seconds == 0)
+ return ERR_SYNC_TIMEOUT;
+
+ // Put the thread to sleep
+ thread->status = THREADSTATUS_WAIT_SYNCH;
- // If this was the first non-waiting object and 'wait_all' is false, don't acquire
- // any other objects
- if (!wait_all)
- break;
+ // Clear the thread's waitlist, we won't use it for wait_all = false
+ thread->wait_objects.clear();
+
+ // Add the thread to each of the objects' waiting threads.
+ for (size_t i = 0; i < objects.size(); ++i) {
+ Kernel::WaitObject* object = objects[i].get();
+ // Set the index of this object in the mapping of Objects -> index for this thread.
+ thread->wait_objects_index[object->GetObjectId()] = static_cast<int>(i);
+ object->AddWaitingThread(thread);
+ // TODO(Subv): Perform things like update the mutex lock owner's priority to
+ // prevent priority inversion. Currently this is done in Mutex::ShouldWait,
+ // but it should be moved to a function that is called from here.
}
- }
- // TODO(bunnei): If 'wait_all' is true, this is probably wrong. However, real hardware does
- // not seem to set it to any meaningful value.
- *out = handle_count != 0 ? (wait_all ? -1 : handle_index) : 0;
+ // Note: If no handles and no timeout were given, then the thread will deadlock, this is
+ // consistent with hardware behavior.
- return RESULT_SUCCESS;
+ // Create an event to wake the thread up after the specified nanosecond delay has passed
+ thread->WakeAfterDelay(nano_seconds);
+
+ // Note: The output of this SVC will be set to RESULT_SUCCESS if the thread resumes due to a
+ // signal in one of its wait objects.
+ // Otherwise we retain the default value of timeout, and -1 in the out parameter
+ thread->wait_set_output = true;
+ *out = -1;
+ return ERR_SYNC_TIMEOUT;
+ }
}
/// Create an address arbiter (to allocate access to shared resources)
@@ -1159,6 +1184,8 @@ void CallSVC(u32 immediate) {
if (info) {
if (info->func) {
info->func();
+ // TODO(Subv): Not all service functions should cause a reschedule in all cases.
+ HLE::Reschedule(__func__);
} else {
LOG_ERROR(Kernel_SVC, "unimplemented SVC function %s(..)", info->name);
}