SPU: Power consumption reduction when using SPU inaccurate reservations

rpcs3/Emu/CPU/CPUThread.cpp

@@ -5,6 +5,7 @@
 #include "Emu/System.h"
 #include "Emu/system_config.h"
 #include "Emu/Memory/vm_locking.h"
+#include "Emu/Memory/vm_reservation.h"
 #include "Emu/IdManager.h"
 #include "Emu/GDB.h"
 #include "Emu/Cell/PPUThread.h"
@@ -892,6 +893,14 @@ cpu_thread& cpu_thread::operator=(thread_state)
 	if (old & cpu_flag::wait && old.none_of(cpu_flag::again + cpu_flag::exit))
 	{
 		state.notify_one(cpu_flag::exit);
+
+		if (auto thread = try_get<spu_thread>())
+		{
+			if (u32 resv = atomic_storage<u32>::load(thread->raddr))
+			{
+				vm::reservation_notifier(resv).notify_one();
+			}
+		}
 	}
 
 	return *this;

rpcs3/Emu/Cell/PPUModule.cpp

@@ -38,6 +38,8 @@ extern void sys_initialize_tls(ppu_thread&, u64, u32, u32, u32);
 // HLE function name cache
 std::vector<std::string> g_ppu_function_names;
 
+extern atomic_t<u32> liblv2_begin = 0, liblv2_end = 0;
+
 extern u32 ppu_generate_id(std::string_view name)
 {
 	// Symbol name suffix
@@ -1367,6 +1369,12 @@ std::shared_ptr<lv2_prx> ppu_load_prx(const ppu_prx_object& elf, const std::stri
 	// Format patch name
 	std::string hash = fmt::format("PRX-%s", fmt::base57(prx->sha1));
 
+	if (prx->path.ends_with("sys/external/liblv2.sprx"sv))
+	{
+		liblv2_begin = prx->segs[0].addr;
+		liblv2_end = prx->segs[0].addr + prx->segs[0].size;
+	}
+
 	std::basic_string<u32> applied;
 
 	for (usz i = 0; i < prx->segs.size(); i++)
@@ -1441,6 +1449,12 @@ void ppu_unload_prx(const lv2_prx& prx)
 	//	}
 	//}
 
+	if (prx.path.ends_with("sys/external/liblv2.sprx"sv))
+	{
+		liblv2_begin = 0;
+		liblv2_end = 0;
+	}
+
 	// Format patch name
 	std::string hash = fmt::format("PRX-%s", fmt::base57(prx.sha1));
 
@@ -1935,6 +1949,9 @@ bool ppu_load_exec(const ppu_exec_object& elf, utils::serial* ar)
 	void init_fxo_for_exec(utils::serial* ar, bool full);
 	init_fxo_for_exec(ar, false);
 
+	liblv2_begin = 0;
+	liblv2_end = 0;
+
 	if (!load_libs.empty())
 	{
 		for (const auto& name : load_libs)

rpcs3/Emu/Cell/PPUThread.cpp

@@ -2642,11 +2642,9 @@ static bool ppu_store_reservation(ppu_thread& ppu, u32 addr, u64 reg_value)
 	}())
 	{
 		// Test a common pattern in lwmutex
-		constexpr u64 mutex_free = u64{static_cast<u32>(0 - 1)} << 32;
-		const bool may_be_lwmutex_related = sizeof(T) == 8 ?
-			(new_data == mutex_free && old_data == u64{ppu.id} << 32) : (old_data == mutex_free && new_data == u64{ppu.id} << 32);
+		extern atomic_t<u32> liblv2_begin, liblv2_end;
 
-		if (!may_be_lwmutex_related)
+		if (ppu.cia < liblv2_begin || ppu.cia >= liblv2_end)
 		{
 			res.notify_all(-128);
 		}

rpcs3/Emu/Cell/SPUThread.cpp

@@ -4336,6 +4336,14 @@ s64 spu_thread::get_ch_value(u32 ch)
 						return true;
 					});
 
+					if (raddr - spurs_addr <= 0x80 && !g_cfg.core.spu_accurate_reservations && mask1 == SPU_EVENT_LR)
+					{
+						// Wait without timeout, in this situation we have notifications for all writes making it possible
+						// Abort notifications are handled specially for performance reasons
+						vm::reservation_notifier(raddr).wait(rtime, -128);
+						continue;	
+					}
+
 					vm::reservation_notifier(raddr).wait(rtime, -128, atomic_wait_timeout{80'000});
 				}
 				else
@@ -5219,6 +5227,8 @@ bool spu_thread::stop_and_signal(u32 code)
 			break;
 		}
 
+		u32 prev_resv = 0;
+
 		for (auto& thread : group->threads)
 		{
 			if (thread)
@@ -5227,10 +5237,26 @@ bool spu_thread::stop_and_signal(u32 code)
 				if (thread.get() != this && thread->state & cpu_flag::ret)
 				{
 					thread_ctrl::notify(*thread);
+
+					if (u32 resv = atomic_storage<u32>::load(thread->raddr))
+					{
+						if (prev_resv && prev_resv != resv)
+						{
+							// Batch reservation notifications if possible
+							vm::reservation_notifier(prev_resv).notify_all();
+						}
+
+						prev_resv = resv;
+					}
 				}
 			}
 		}
-
+
+		if (prev_resv)
+		{
+			vm::reservation_notifier(prev_resv).notify_all();
+		}
+
 		check_state();
 		return true;
 	}

rpcs3/Emu/Cell/lv2/sys_spu.cpp

@@ -14,6 +14,7 @@
 #include "Emu/Cell/PPUThread.h"
 #include "Emu/Cell/RawSPUThread.h"
 #include "Emu/Cell/timers.hpp"
+#include "Emu/Memory/vm_reservation.h"
 #include "sys_interrupt.h"
 #include "sys_process.h"
 #include "sys_memory.h"
@@ -1365,14 +1366,32 @@ error_code sys_spu_thread_group_terminate(ppu_thread& ppu, u32 id, s32 value)
 		}
 	}
 
+	u32 prev_resv = 0;
+
 	for (auto& thread : group->threads)
 	{
 		while (thread && group->running && thread->state & cpu_flag::wait)
 		{
 			thread_ctrl::notify(*thread);
+
+			if (u32 resv = atomic_storage<u32>::load(thread->raddr))
+			{
+				if (prev_resv && prev_resv != resv)
+				{
+					// Batch reservation notifications if possible
+					vm::reservation_notifier(prev_resv).notify_all();
+				}
+
+				prev_resv = resv;
+			}
 		}
 	}
 
+	if (prev_resv)
+	{
+		vm::reservation_notifier(prev_resv).notify_all();
+	}
+
 	group->exit_status = value;
 	group->join_state = SYS_SPU_THREAD_GROUP_JOIN_TERMINATED;