Add ability to redirect app core1 threads to core2

N3DS-only option. See config.ini for details and context. This should
make very demanding games (those which already use 3x clockrate and L2C
by default, like Pokémon US/UM) between 5 to 15% faster. Not widely
tested, and can potentially break some games and other apps.

arm9/source/config.c

@@ -62,6 +62,7 @@ static const char *singleOptionIniNamesBoot[] = {
     "use_emunand_firm_if_r_pressed",
     "enable_external_firm_and_modules",
     "enable_game_patching",
+    "app_syscore_threads_on_core_2",
     "show_system_settings_string",
     "show_gba_boot_screen",
 };
@@ -544,7 +545,8 @@ static size_t saveLumaIniConfigToStr(char *out)
         (int)CONFIG_VERSIONMAJOR, (int)CONFIG_VERSIONMINOR,
         (int)CONFIG(AUTOBOOTEMU), (int)CONFIG(USEEMUFIRM),
         (int)CONFIG(LOADEXTFIRMSANDMODULES), (int)CONFIG(PATCHGAMES),
-        (int)CONFIG(PATCHVERSTRING), (int)CONFIG(SHOWGBABOOT),
+        (int)CONFIG(REDIRECTAPPTHREADS), (int)CONFIG(PATCHVERSTRING),
+        (int)CONFIG(SHOWGBABOOT),
 
         1 + (int)MULTICONFIG(DEFAULTEMU), 4 - (int)MULTICONFIG(BRIGHTNESS),
         splashPosStr, (unsigned int)cfg->splashDurationMsec,
@@ -716,6 +718,7 @@ void configMenu(bool oldPinStatus, u32 oldPinMode)
                                                "( ) Use EmuNAND FIRM if booting with R",
                                                "( ) Enable loading external FIRMs and modules",
                                                "( ) Enable game patching",
+                                               "( ) Redirect app. syscore threads to core2",
                                                "( ) Show NAND or user string in System Settings",
                                                "( ) Show GBA boot screen in patched AGB_FIRM",
                                              };
@@ -793,6 +796,15 @@ void configMenu(bool oldPinStatus, u32 oldPinMode)
                                                  "for out-of-region games work.\n\n"
                                                  "Refer to the wiki for instructions.",
 
+                                                 "Redirect app. threads that would spawn\n"
+                                                 "on core1, to core2 (which is an extra\n"
+                                                 "CPU core for applications that usually\n"
+                                                 "remains unused).\n\n"
+                                                 "This improves the performance of very\n"
+                                                 "demanding games (like Pok\x82mon US/UM)\n" // CP437
+                                                 "by about 10%. Can break some games\n"
+                                                 "and other applications.\n",
+
                                                  "Enable showing the current NAND/FIRM:\n\n"
                                                  "\t* Sys  = SysNAND\n"
                                                  "\t* Emu  = EmuNAND 1\n"
@@ -839,6 +851,7 @@ void configMenu(bool oldPinStatus, u32 oldPinMode)
         { .visible = nandType == FIRMWARE_EMUNAND },
         { .visible = true },
         { .visible = true },
+        { .visible = ISN3DS },
         { .visible = true },
         { .visible = true },
     };

arm9/source/config.h

@@ -36,7 +36,7 @@
 
 #define CONFIG_FILE         "config.bin"
 #define CONFIG_VERSIONMAJOR 3
-#define CONFIG_VERSIONMINOR 2
+#define CONFIG_VERSIONMINOR 3
 
 #define BOOTCFG_NAND         BOOTCONFIG(0, 7)
 #define BOOTCFG_FIRM         BOOTCONFIG(3, 7)
@@ -59,6 +59,7 @@ enum singleOptions
     USEEMUFIRM,
     LOADEXTFIRMSANDMODULES,
     PATCHGAMES,
+    REDIRECTAPPTHREADS,
     PATCHVERSTRING,
     SHOWGBABOOT,
     PATCHUNITINFO,

k11_extension/include/config.h

@@ -30,6 +30,7 @@ enum singleOptions
     USEEMUFIRM,
     LOADEXTFIRMSANDMODULES,
     PATCHGAMES,
+    REDIRECTAPPTHREADS,
     PATCHVERSTRING,
     SHOWGBABOOT,
     PATCHUNITINFO,

k11_extension/include/globals.h

@@ -54,6 +54,7 @@ extern void (*KScheduler__AdjustThread)(KScheduler *this, KThread *thread, u32 o
 extern void (*KScheduler__AttemptSwitchingThreadContext)(KScheduler *this);
 
 extern Result (*ControlMemory)(u32 *addrOut, u32 addr0, u32 addr1, u32 size, MemOp op, MemPerm perm, bool isLoader);
+extern Result (*CreateThread)(Handle *outThreadHandle, u32 ep, u32 arg, u32 stackTop, s32 priority, s32 processorId);
 extern void (*SleepThread)(s64 ns);
 extern Result (*CloseHandle)(Handle handle);
 extern Result (*GetHandleInfo)(s64 *out, Handle handle, u32 type);

k11_extension/include/kernel.h

@@ -1162,7 +1162,7 @@ offsetof(classname##O3DSPre8x, field)))
 #define KPROCESSHWINFO_GET_RVALUE(obj, field)             *(KPROCESSHWINFO_GET_PTR(obj, field))
 #define KPROCESSHWINFO_GET_RVALUE_TYPE(type, obj, field)  *(KPROCESSHWINFO_GET_PTR_TYPE(type, obj, field))
 
-extern u32 pidOffsetKProcess, hwInfoOffsetKProcess, codeSetOffsetKProcess, handleTableOffsetKProcess, debugOffsetKProcess;
+extern u32 pidOffsetKProcess, hwInfoOffsetKProcess, codeSetOffsetKProcess, handleTableOffsetKProcess, debugOffsetKProcess, flagsKProcess;
 
 static inline u32 idOfProcess(KProcess *process)
 {
@@ -1195,6 +1195,13 @@ static inline KDebug *debugOfProcess(KProcess *process)
     return debug;
 }
 
+static inline u32 flagsOfProcess(KProcess *process)
+{
+    u32 flags;
+    memcpy(&flags, (const u8 *)process + flagsKProcess, 4);
+    return flags;
+}
+
 static inline const char *classNameOfAutoObject(KAutoObject *object)
 {
     const char *name;

k11_extension/include/svc/CreateThread.h

@@ -0,0 +1,32 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2016-2023 Aurora Wright, TuxSH
+*
+*   This program is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   This program is distributed in the hope that 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/>.
+*
+*   Additional Terms 7.b and 7.c of GPLv3 apply to this file:
+*       * Requiring preservation of specified reasonable legal notices or
+*         author attributions in that material or in the Appropriate Legal
+*         Notices displayed by works containing it.
+*       * Prohibiting misrepresentation of the origin of that material,
+*         or requiring that modified versions of such material be marked in
+*         reasonable ways as different from the original version.
+*/
+
+#include "utils.h"
+#include "kernel.h"
+#include "svc.h"
+
+Result CreateThreadHookWrapper(Handle *outThreadHandle, u32 ep, u32 arg, u32 stackTop, s32 priority, s32 processorId);
+Result CreateThreadHook(Handle *outThreadHandle, u32 ep, u32 arg, u32 stackTop, s32 priority, s32 processorId);

k11_extension/source/globals.c

@@ -50,6 +50,7 @@ void (*KScheduler__AdjustThread)(KScheduler *this, KThread *thread, u32 oldSched
 void (*KScheduler__AttemptSwitchingThreadContext)(KScheduler *this);
 
 Result (*ControlMemory)(u32 *addrOut, u32 addr0, u32 addr1, u32 size, MemOp op, MemPerm perm, bool isLoader);
+Result (*CreateThread)(Handle *outThreadHandle, u32 ep, u32 arg, u32 stackTop, s32 priority, s32 processorId);
 void (*SleepThread)(s64 ns);
 Result (*CloseHandle)(Handle handle);
 Result (*GetHandleInfo)(s64 *out, Handle handle, u32 type);
@@ -114,4 +115,4 @@ u32 stolenSystemMemRegionSize;
 vu32 rosalinaState;
 bool hasStartedRosalinaNetworkFuncsOnce;
 
-u32 pidOffsetKProcess, hwInfoOffsetKProcess, codeSetOffsetKProcess, handleTableOffsetKProcess, debugOffsetKProcess;
+u32 pidOffsetKProcess, hwInfoOffsetKProcess, codeSetOffsetKProcess, handleTableOffsetKProcess, debugOffsetKProcess, flagsKProcess;

k11_extension/source/main.c

@@ -127,6 +127,7 @@ void configHook(vu8 *cfgPage)
     codeSetOffsetKProcess = KPROCESS_OFFSETOF(codeSet);
     handleTableOffsetKProcess = KPROCESS_OFFSETOF(handleTable);
     debugOffsetKProcess = KPROCESS_OFFSETOF(debug);
+    flagsKProcess = KPROCESS_OFFSETOF(kernelFlags);
 }
 
 static void findUsefulSymbols(void)
@@ -240,6 +241,7 @@ static void findUsefulSymbols(void)
     // The official prototype of ControlMemory doesn't have that extra param'
     ControlMemory = (Result (*)(u32 *, u32, u32, u32, MemOp, MemPerm, bool))
                     decodeArmBranch((u32 *)officialSVCs[0x01] + 5);
+    CreateThread = (Result (*)(Handle *, u32, u32, u32, s32, s32))decodeArmBranch((u32 *)officialSVCs[0x08] + 5);
     SleepThread = (void (*)(s64))officialSVCs[0x0A];
     CloseHandle = (Result (*)(Handle))officialSVCs[0x23];
     GetHandleInfo = (Result (*)(s64 *, Handle, u32))decodeArmBranch((u32 *)officialSVCs[0x29] + 3);

k11_extension/source/svc.c

@@ -28,6 +28,7 @@
 #include "synchronization.h"
 #include "svc.h"
 #include "svc/ControlMemory.h"
+#include "svc/CreateThread.h"
 #include "svc/GetHandleInfo.h"
 #include "svc/GetSystemInfo.h"
 #include "svc/GetProcessInfo.h"
@@ -63,6 +64,8 @@ void buildAlteredSvcTable(void)
 
     alteredSvcTable[0x01] = ControlMemoryHookWrapper;
 
+    if (isN3DS)
+        alteredSvcTable[0x08] = CreateThreadHookWrapper;
     alteredSvcTable[0x29] = GetHandleInfoHookWrapper;
     alteredSvcTable[0x2A] = GetSystemInfoHookWrapper;
     alteredSvcTable[0x2B] = GetProcessInfoHookWrapper;

k11_extension/source/svc/CreateThread.c

@@ -0,0 +1,37 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2016-2023 Aurora Wright, TuxSH
+*
+*   This program is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   This program is distributed in the hope that 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/>.
+*
+*   Additional Terms 7.b and 7.c of GPLv3 apply to this file:
+*       * Requiring preservation of specified reasonable legal notices or
+*         author attributions in that material or in the Appropriate Legal
+*         Notices displayed by works containing it.
+*       * Prohibiting misrepresentation of the origin of that material,
+*         or requiring that modified versions of such material be marked in
+*         reasonable ways as different from the original version.
+*/
+
+#include "svc/CreateThread.h"
+
+Result CreateThreadHook(Handle *outThreadHandle, u32 ep, u32 arg, u32 stackTop, s32 priority, s32 processorId)
+{
+    u32 flags = flagsOfProcess(currentCoreContext->objectContext.currentProcess);
+    if (isN3DS && CONFIG(REDIRECTAPPTHREADS) && processorId == 1 && (flags & 0xF00) == 0x100)
+        processorId = 2;
+
+    return CreateThread(outThreadHandle, ep, arg, stackTop, priority, processorId);
+}
+

k11_extension/source/svc/wrappers.s

@@ -84,3 +84,16 @@ ControlMemoryEx:
     ldr r1, [sp, #12]
     add sp, #20
     pop {pc}
+
+.global CreateThreadHookWrapper
+.type   CreateThreadHookWrapper, %function
+CreateThreadHookWrapper:
+    push {lr}
+    sub sp, #12
+    str r4, [sp, #4]
+    str r0, [sp]
+    add r0, sp, #8
+    bl CreateThreadHook
+    ldr r1, [sp, #8]
+    add sp, sp, #12
+    pop {pc}

sysmodules/loader/source/patcher.h

@@ -33,6 +33,7 @@ enum singleOptions
     USEEMUFIRM,
     LOADEXTFIRMSANDMODULES,
     PATCHGAMES,
+    REDIRECTAPPTHREADS,
     PATCHVERSTRING,
     SHOWGBABOOT,
     PATCHUNITINFO,

sysmodules/pm/source/luma.c

@@ -3,6 +3,23 @@
 #include "luma.h"
 #include "util.h"
 
+u32 config, multiConfig, bootConfig;
+
+void readLumaConfig(void)
+{
+    s64 out = 0;
+    bool isLumaWithKext = svcGetSystemInfo(&out, 0x20000, 0) == 1;
+    if (isLumaWithKext)
+    {
+        svcGetSystemInfo(&out, 0x10000, 3);
+        config = (u32)out;
+        svcGetSystemInfo(&out, 0x10000, 4);
+        multiConfig = (u32)out;
+        svcGetSystemInfo(&out, 0x10000, 5);
+        bootConfig = (u32)out;
+    }
+}
+
 bool hasKExt(void)
 {
     s64 val;

sysmodules/pm/source/luma.h

@@ -2,6 +2,42 @@
 
 #include <3ds/types.h>
 
+#define CONFIG(a)        (((config >> (a)) & 1) != 0)
+#define MULTICONFIG(a)   ((multiConfig >> (2 * (a))) & 3)
+#define BOOTCONFIG(a, b) ((bootConfig >> (a)) & (b))
+
+#define BOOTCFG_NAND         BOOTCONFIG(0, 7)
+#define BOOTCFG_FIRM         BOOTCONFIG(3, 7)
+#define BOOTCFG_NOFORCEFLAG  BOOTCONFIG(6, 1)
+#define BOOTCFG_NTRCARDBOOT  BOOTCONFIG(7, 1)
+
+enum multiOptions
+{
+    DEFAULTEMU = 0,
+    BRIGHTNESS,
+    SPLASH,
+    PIN,
+    NEWCPU,
+    AUTOBOOTMODE,
+};
+
+enum singleOptions
+{
+    AUTOBOOTEMU = 0,
+    USEEMUFIRM,
+    LOADEXTFIRMSANDMODULES,
+    PATCHGAMES,
+    REDIRECTAPPTHREADS,
+    PATCHVERSTRING,
+    SHOWGBABOOT,
+    PATCHUNITINFO,
+    DISABLEARM11EXCHANDLERS,
+    ENABLESAFEFIRMROSALINA,
+};
+
+extern u32 config, multiConfig, bootConfig;
+
+void readLumaConfig(void);
 bool hasKExt(void);
 u32 getKExtSize(void);
 u32 getStolenSystemMemRegionSize(void);

sysmodules/pm/source/main.c

@@ -13,6 +13,7 @@
 #include "util.h"
 #include "my_thread.h"
 #include "service_manager.h"
+#include "luma.h"
 
 static MyThread processMonitorThread, taskRunnerThread;
 static u8 ALIGN(8) processDataBuffer[0x40 * sizeof(ProcessData)] = {0};
@@ -34,6 +35,7 @@ Result __sync_init(void);
 void initSystem()
 {
     __sync_init();
+    readLumaConfig();
     //__libc_init_array();
 
     // Wait for sm

sysmodules/pm/source/reslimit.c

@@ -308,6 +308,11 @@ Result resetAppMemLimit(void)
 
 Result setAppCpuTimeLimit(s64 limit)
 {
+    // Prevent apps from enabling preemption on core1 (and kernel will
+    // redirect apps threads from core 1 to 2).
+    if (IS_N3DS && CONFIG(REDIRECTAPPTHREADS))
+        return 0;
+
     ResourceLimitType category = RESLIMIT_CPUTIME;
     return svcSetResourceLimitValues(g_manager.reslimits[0], &category, &limit, 1);
 }

sysmodules/rosalina/source/menus/miscellaneous.c

@@ -49,6 +49,7 @@ enum singleOptions
     USEEMUFIRM,
     LOADEXTFIRMSANDMODULES,
     PATCHGAMES,
+    REDIRECTAPPTHREADS,
     PATCHVERSTRING,
     SHOWGBABOOT,
     PATCHUNITINFO,
@@ -315,7 +316,8 @@ static size_t saveLumaIniConfigToStr(char *out, const CfgData *cfg)
         (int)cfg->formatVersionMajor, (int)cfg->formatVersionMinor,
         (int)CONFIG(AUTOBOOTEMU), (int)CONFIG(USEEMUFIRM),
         (int)CONFIG(LOADEXTFIRMSANDMODULES), (int)CONFIG(PATCHGAMES),
-        (int)CONFIG(PATCHVERSTRING), (int)CONFIG(SHOWGBABOOT),
+        (int)CONFIG(REDIRECTAPPTHREADS), (int)CONFIG(PATCHVERSTRING),
+        (int)CONFIG(SHOWGBABOOT),
 
         1 + (int)MULTICONFIG(DEFAULTEMU), 4 - (int)MULTICONFIG(BRIGHTNESS),
         splashPosStr, (unsigned int)cfg->splashDurationMsec,