From 7b9f428b23e1761e7b6c177d2e8eb9219ac6b7f6 Mon Sep 17 00:00:00 2001 From: bunnei Date: Mon, 23 Mar 2015 23:55:21 -0400 Subject: Thread: Implement priority boost for starved threads. SVC: Return correct error code on invalid CreateThread processor ID. SVC: Assert when creating a thread with an invalid userland priority. --- src/common/thread_queue_list.h | 18 +++++++++++++++ src/core/hle/function_wrappers.h | 7 ++++++ src/core/hle/kernel/thread.cpp | 48 ++++++++++++++++++++++++++++++---------- src/core/hle/kernel/thread.h | 25 ++++++++++++--------- src/core/hle/svc.cpp | 22 +++++++++++++----- 5 files changed, 92 insertions(+), 28 deletions(-) (limited to 'src') diff --git a/src/common/thread_queue_list.h b/src/common/thread_queue_list.h index 444abf11..4f27fc89 100644 --- a/src/common/thread_queue_list.h +++ b/src/common/thread_queue_list.h @@ -40,6 +40,18 @@ struct ThreadQueueList { return -1; } + T get_first() { + Queue *cur = first; + while (cur != nullptr) { + if (!cur->data.empty()) { + return cur->data.front(); + } + cur = cur->next_nonempty; + } + + return T(); + } + T pop_first() { Queue *cur = first; while (cur != nullptr) { @@ -79,6 +91,12 @@ struct ThreadQueueList { cur->data.push_back(thread_id); } + void move(const T& thread_id, Priority old_priority, Priority new_priority) { + remove(old_priority, thread_id); + prepare(new_priority); + push_back(new_priority, thread_id); + } + void remove(Priority priority, const T& thread_id) { Queue *cur = &queues[priority]; boost::remove_erase(cur->data, thread_id); diff --git a/src/core/hle/function_wrappers.h b/src/core/hle/function_wrappers.h index 0b6b6f51..be2626ee 100644 --- a/src/core/hle/function_wrappers.h +++ b/src/core/hle/function_wrappers.h @@ -46,6 +46,13 @@ template void Wrap(){ FuncReturn(retval); } +template void Wrap() { + u32 param_1 = 0; + u32 retval = func(¶m_1, PARAM(0), PARAM(1), PARAM(2), PARAM(3), PARAM(4)).raw; + Core::g_app_core->SetReg(1, param_1); + FuncReturn(retval); +} + template void Wrap() { s32 param_1 = 0; s32 retval = func(¶m_1, (Handle*)Memory::GetPointer(PARAM(1)), (s32)PARAM(2), diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp index be1aed61..3a1e15ac 100644 --- a/src/core/hle/kernel/thread.cpp +++ b/src/core/hle/kernel/thread.cpp @@ -140,6 +140,29 @@ void ArbitrateAllThreads(u32 address) { } } +/// Boost low priority threads (temporarily) that have been starved +static void PriorityBoostStarvedThreads() { + u64 current_ticks = CoreTiming::GetTicks(); + + for (auto& thread : thread_list) { + // TODO(bunnei): Threads that have been waiting to be scheduled for `boost_ticks` (or + // longer) will have their priority temporarily adjusted to 1 higher than the highest + // priority thread to prevent thread starvation. This general behavior has been verified + // on hardware. However, this is almost certainly not perfect, and the real CTR OS scheduler + // should probably be reversed to verify this. + + const u64 boost_timeout = 2000000; // Boost threads that have been ready for > this long + + u64 delta = current_ticks - thread->last_running_ticks; + + if (thread->status == THREADSTATUS_READY && delta > boost_timeout && !thread->idle) { + const s32 boost_priority = std::max(ready_queue.get_first()->current_priority - 1, 0); + ready_queue.move(thread, thread->current_priority, boost_priority); + thread->current_priority = boost_priority; + } + } +} + /** * Switches the CPU's active thread context to that of the specified thread * @param new_thread The thread to switch to @@ -151,6 +174,7 @@ static void SwitchContext(Thread* new_thread) { // Save context for previous thread if (previous_thread) { + previous_thread->last_running_ticks = CoreTiming::GetTicks(); Core::g_app_core->SaveContext(previous_thread->context); if (previous_thread->status == THREADSTATUS_RUNNING) { @@ -168,6 +192,9 @@ static void SwitchContext(Thread* new_thread) { ready_queue.remove(new_thread->current_priority, new_thread); new_thread->status = THREADSTATUS_RUNNING; + // Restores thread to its nominal priority if it has been temporarily changed + new_thread->current_priority = new_thread->nominal_priority; + Core::g_app_core->LoadContext(new_thread->context); } else { current_thread = nullptr; @@ -364,7 +391,8 @@ ResultVal> Thread::Create(std::string name, VAddr entry_point, thread->status = THREADSTATUS_DORMANT; thread->entry_point = entry_point; thread->stack_top = stack_top; - thread->initial_priority = thread->current_priority = priority; + thread->nominal_priority = thread->current_priority = priority; + thread->last_running_ticks = CoreTiming::GetTicks(); thread->processor_id = processor_id; thread->wait_set_output = false; thread->wait_all = false; @@ -400,18 +428,11 @@ static void ClampPriority(const Thread* thread, s32* priority) { void Thread::SetPriority(s32 priority) { ClampPriority(this, &priority); - if (current_priority == priority) { - return; - } + // If thread was ready, adjust queues + if (status == THREADSTATUS_READY) + ready_queue.move(this, current_priority, priority); - if (status == THREADSTATUS_READY) { - // If thread was ready, adjust queues - ready_queue.remove(current_priority, this); - ready_queue.prepare(priority); - ready_queue.push_back(priority, this); - } - - current_priority = priority; + nominal_priority = current_priority = priority; } SharedPtr SetupIdleThread() { @@ -440,6 +461,9 @@ SharedPtr SetupMainThread(u32 stack_size, u32 entry_point, s32 priority) void Reschedule() { Thread* prev = GetCurrentThread(); + + PriorityBoostStarvedThreads(); + Thread* next = PopNextReadyThread(); HLE::g_reschedule = false; diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h index bde4eecf..92f2c423 100644 --- a/src/core/hle/kernel/thread.h +++ b/src/core/hle/kernel/thread.h @@ -17,16 +17,19 @@ #include "core/hle/kernel/kernel.h" #include "core/hle/result.h" -enum ThreadPriority { - THREADPRIO_HIGHEST = 0x0, ///< Highest thread priority - THREADPRIO_DEFAULT = 0x30, ///< Default thread priority for userland apps - THREADPRIO_LOWEST = 0x3F, ///< Lowest thread priority +enum ThreadPriority : s32{ + THREADPRIO_HIGHEST = 0, ///< Highest thread priority + THREADPRIO_USERLAND_MAX = 24, ///< Highest thread priority for userland apps + THREADPRIO_DEFAULT = 48, ///< Default thread priority for userland apps + THREADPRIO_LOWEST = 63, ///< Lowest thread priority }; -enum ThreadProcessorId { - THREADPROCESSORID_0 = 0xFFFFFFFE, ///< Enables core appcode - THREADPROCESSORID_1 = 0xFFFFFFFD, ///< Enables core syscore - THREADPROCESSORID_ALL = 0xFFFFFFFC, ///< Enables both cores +enum ThreadProcessorId : s32 { + THREADPROCESSORID_DEFAULT = -2, ///< Run thread on default core specified by exheader + THREADPROCESSORID_ALL = -1, ///< Run thread on either core + THREADPROCESSORID_0 = 0, ///< Run thread on core 0 (AppCore) + THREADPROCESSORID_1 = 1, ///< Run thread on core 1 (SysCore) + THREADPROCESSORID_MAX = 2, ///< Processor ID must be less than this }; enum ThreadStatus { @@ -134,8 +137,10 @@ public: u32 entry_point; u32 stack_top; - s32 initial_priority; - s32 current_priority; + s32 nominal_priority; ///< Nominal thread priority, as set by the emulated application + s32 current_priority; ///< Current thread priority, can be temporarily changed + + u64 last_running_ticks; ///< CPU tick when thread was last running s32 processor_id; diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp index e89e9723..82e18746 100644 --- a/src/core/hle/svc.cpp +++ b/src/core/hle/svc.cpp @@ -312,7 +312,7 @@ static ResultCode GetResourceLimitCurrentValues(s64* values, Handle resource_lim } /// Creates a new thread -static ResultCode CreateThread(u32* out_handle, u32 priority, u32 entry_point, u32 arg, u32 stack_top, u32 processor_id) { +static ResultCode CreateThread(Handle* out_handle, s32 priority, u32 entry_point, u32 arg, u32 stack_top, s32 processor_id) { using Kernel::Thread; std::string name; @@ -323,6 +323,21 @@ static ResultCode CreateThread(u32* out_handle, u32 priority, u32 entry_point, u name = Common::StringFromFormat("unknown-%08x", entry_point); } + // TODO(bunnei): Implement resource limits to return an error code instead of the below assert. + // The error code should be: Description::NotAuthorized, Module::OS, Summary::WrongArgument, + // Level::Permanent + ASSERT_MSG(priority >= THREADPRIO_USERLAND_MAX, "Unexpected thread priority!"); + + if (priority > THREADPRIO_LOWEST) { + return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS, + ErrorSummary::InvalidArgument, ErrorLevel::Usage); + } + + if (processor_id > THREADPROCESSORID_MAX) { + return ResultCode(ErrorDescription::OutOfRange, ErrorModule::Kernel, + ErrorSummary::InvalidArgument, ErrorLevel::Permanent); + } + CASCADE_RESULT(SharedPtr thread, Kernel::Thread::Create( name, entry_point, priority, arg, processor_id, stack_top)); CASCADE_RESULT(*out_handle, Kernel::g_handle_table.Create(std::move(thread))); @@ -331,11 +346,6 @@ static ResultCode CreateThread(u32* out_handle, u32 priority, u32 entry_point, u "threadpriority=0x%08X, processorid=0x%08X : created handle=0x%08X", entry_point, name.c_str(), arg, stack_top, priority, processor_id, *out_handle); - if (THREADPROCESSORID_1 == processor_id) { - LOG_WARNING(Kernel_SVC, - "thread designated for system CPU core (UNIMPLEMENTED) will be run with app core scheduling"); - } - HLE::Reschedule(__func__); return RESULT_SUCCESS; -- cgit v1.2.3