kern: add debug thread dump

libraries/libmesosphere/include/mesosphere.hpp

@@ -54,6 +54,7 @@
 #include <mesosphere/kern_kernel.hpp>
 #include <mesosphere/kern_k_page_table_manager.hpp>
 #include <mesosphere/kern_select_page_table.hpp>
+#include <mesosphere/kern_k_dump_object.hpp>
 
 /* Miscellaneous objects. */
 #include <mesosphere/kern_k_shared_memory_info.hpp>

libraries/libmesosphere/include/mesosphere/kern_build_config.hpp

@@ -26,6 +26,7 @@
 #ifdef  MESOSPHERE_BUILD_FOR_DEBUGGING
 #define MESOSPHERE_ENABLE_ASSERTIONS
 #define MESOSPHERE_ENABLE_DEBUG_PRINT
+#define MESOSPHERE_ENABLE_KERNEL_STACK_USAGE
 #endif
 
 //#define MESOSPHERE_BUILD_FOR_TRACING

libraries/libmesosphere/include/mesosphere/kern_k_dump_object.hpp

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2018-2020 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/>.
+ */
+#pragma once
+#include <mesosphere/kern_common.hpp>
+#include <mesosphere/kern_select_cpu.hpp>
+
+namespace ams::kern::KDumpObject {
+
+    void DumpThread();
+    void DumpThread(u64 thread_id);
+
+}

libraries/libmesosphere/include/mesosphere/kern_k_thread.hpp

@@ -533,6 +533,7 @@ namespace ams::kern {
                 return this->termination_requested || this->GetRawState() == ThreadState_Terminated;
             }
 
+            size_t GetKernelStackUsage() const;
         public:
             /* Overridden parent functions. */
             virtual u64 GetId() const override final { return this->GetThreadId(); }

libraries/libmesosphere/source/kern_k_dump_object.cpp

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2018-2020 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 <mesosphere.hpp>
+
+namespace ams::kern::KDumpObject {
+
+    namespace {
+
+        constexpr const char * const ThreadStates[] = {
+            [KThread::ThreadState_Initialized] = "Initialized",
+            [KThread::ThreadState_Waiting]     = "Waiting",
+            [KThread::ThreadState_Runnable]    = "Runnable",
+            [KThread::ThreadState_Terminated]  = "Terminated",
+        };
+
+        void DumpThread(KThread *thread) {
+            if (KProcess *process = thread->GetOwnerProcess(); process != nullptr) {
+                MESOSPHERE_LOG("Thread ID=%5lu pid=%3lu %-11s Pri=%2d %-11s KernelStack=%4zu/%4zu Run=%d Ideal=%d (%d) Affinity=%016lx (%016lx)\n",
+                               thread->GetId(), process->GetId(), process->GetName(), thread->GetPriority(), ThreadStates[thread->GetState()],
+                               thread->GetKernelStackUsage(), PageSize, thread->GetActiveCore(), thread->GetIdealVirtualCore(), thread->GetIdealPhysicalCore(),
+                               thread->GetVirtualAffinityMask(), thread->GetAffinityMask().GetAffinityMask());
+
+                MESOSPHERE_LOG("    State: 0x%04x Suspend: 0x%04x Dpc: 0x%x\n", thread->GetRawState(), thread->GetSuspendFlags(), thread->GetDpc());
+
+                MESOSPHERE_LOG("    TLS: %p (%p)\n", GetVoidPointer(thread->GetThreadLocalRegionAddress()), thread->GetThreadLocalRegionHeapAddress());
+            } else {
+                MESOSPHERE_LOG("Thread ID=%5lu pid=%3d %-11s Pri=%2d %-11s KernelStack=%4zu/%4zu Run=%d Ideal=%d (%d) Affinity=%016lx (%016lx)\n",
+                               thread->GetId(), -1, "(kernel)", thread->GetPriority(), ThreadStates[thread->GetState()],
+                               thread->GetKernelStackUsage(), PageSize, thread->GetActiveCore(), thread->GetIdealVirtualCore(), thread->GetIdealPhysicalCore(),
+                               thread->GetVirtualAffinityMask(), thread->GetAffinityMask().GetAffinityMask());
+            }
+        }
+
+    }
+
+    void DumpThread() {
+        MESOSPHERE_LOG("Dump Thread\n");
+
+        {
+            /* Lock the list. */
+            KThread::ListAccessor accessor;
+            const auto end = accessor.end();
+
+            /* Dump each thread. */
+            for (auto it = accessor.begin(); it != end; ++it) {
+                DumpThread(static_cast<KThread *>(std::addressof(*it)));
+            }
+        }
+
+        MESOSPHERE_LOG("\n");
+    }
+
+    void DumpThread(u64 thread_id) {
+        MESOSPHERE_LOG("Dump Thread\n");
+
+        {
+            /* Find and dump the target thread. */
+            if (KThread *thread = KThread::GetThreadFromId(thread_id); thread != nullptr) {
+                ON_SCOPE_EXIT { thread->Close(); };
+                DumpThread(thread);
+            }
+        }
+
+        MESOSPHERE_LOG("\n");
+    }
+
+}

libraries/libmesosphere/source/kern_k_thread.cpp

@@ -24,6 +24,15 @@ namespace ams::kern {
             return KernelVirtualAddressSpaceBase <= key_uptr && key_uptr <= KernelVirtualAddressSpaceLast;
         }
 
+        void InitializeKernelStack(uintptr_t stack_top) {
+            #if defined(MESOSPHERE_ENABLE_KERNEL_STACK_USAGE)
+                const uintptr_t stack_bottom = stack_top - PageSize;
+                std::memset(reinterpret_cast<void *>(stack_bottom), 0xCC, PageSize - sizeof(KThread::StackParameters));
+            #else
+                MESOSPHERE_UNUSED(stack_top);
+            #endif
+        }
+
         void CleanupKernelStack(uintptr_t stack_top) {
             const uintptr_t stack_bottom = stack_top - PageSize;
 
@@ -153,6 +162,11 @@ namespace ams::kern {
         this->resource_limit_release_hint   = 0;
         this->cpu_time                      = 0;
 
+        /* Setup our kernel stack. */
+        if (type != ThreadType_Main) {
+            InitializeKernelStack(reinterpret_cast<uintptr_t>(kern_stack_top));
+        }
+
         /* Clear our stack parameters. */
         std::memset(static_cast<void *>(std::addressof(this->GetStackParameters())), 0, sizeof(StackParameters));
 
@@ -803,6 +817,26 @@ namespace ams::kern {
         KScheduler::OnThreadStateChanged(this, old_state);
     }
 
+    size_t KThread::GetKernelStackUsage() const {
+        MESOSPHERE_ASSERT_THIS();
+        MESOSPHERE_ASSERT(this->kernel_stack_top != nullptr);
+
+        #if defined(MESOSPHERE_ENABLE_KERNEL_STACK_USAGE)
+            const u8 *stack = static_cast<const u8 *>(this->kernel_stack_top) - PageSize;
+
+            size_t i;
+            for (i = 0; i < PageSize; ++i) {
+                if (stack[i] != 0xCC) {
+                    break;
+                }
+            }
+
+            return PageSize - i;
+        #else
+            return 0;
+        #endif
+    }
+
     Result KThread::SetActivity(ams::svc::ThreadActivity activity) {
         /* Lock ourselves. */
         KScopedLightLock lk(this->activity_pause_lock);

libraries/libmesosphere/source/svc/kern_svc_kernel_debug.cpp

@@ -22,19 +22,27 @@ namespace ams::kern::svc {
     namespace {
 
         void KernelDebug(ams::svc::KernelDebugType kern_debug_type, uint64_t arg0, uint64_t arg1, uint64_t arg2) {
-            #ifdef ATMOSPHERE_BUILD_FOR_DEBUGGING
-            {
-                /* TODO: Implement Kernel Debugging. */
-            }
-            #else
-            {
             MESOSPHERE_UNUSED(kern_debug_type, arg0, arg1, arg2);
+
+            #ifdef MESOSPHERE_BUILD_FOR_DEBUGGING
+            {
+                switch (kern_debug_type) {
+                    case ams::svc::KernelDebugType_Thread:
+                        if (arg0 == static_cast<u64>(-1)) {
+                            KDumpObject::DumpThread();
+                        } else {
+                            KDumpObject::DumpThread(arg0);
+                        }
+                        break;
+                    default:
+                        break;
+                }
             }
             #endif
         }
 
         void ChangeKernelTraceState(ams::svc::KernelTraceState kern_trace_state) {
-            #ifdef ATMOSPHERE_BUILD_FOR_DEBUGGING
+            #ifdef MESOSPHERE_BUILD_FOR_DEBUGGING
             {
                 switch (kern_trace_state) {
                     case ams::svc::KernelTraceState_Enabled:

libraries/libvapours/include/vapours/svc/svc_types_common.hpp

@@ -470,7 +470,7 @@ namespace ams::svc {
     };
 
     enum KernelDebugType : u32 {
-        /* TODO */
+        KernelDebugType_Thread = 0,
     };
 
     enum KernelTraceState : u32 {