kern: partially implement SvcSignalProcessWideKey

libraries/libmesosphere/include/mesosphere/kern_k_condition_variable.hpp

@@ -64,6 +64,8 @@ namespace ams::kern {
 
                 this->tree.insert(*thread);
             }
+        private:
+            KThread *SignalImpl(KThread *thread);
     };
 
 }

libraries/libmesosphere/include/mesosphere/kern_k_process.hpp

@@ -192,6 +192,22 @@ namespace ams::kern {
 
             void SetPreemptionState();
 
+            Result SignalToAddress(KProcessAddress address) {
+                return this->cond_var.SignalToAddress(address);
+            }
+
+            Result WaitForAddress(ams::svc::Handle handle, KProcessAddress address, u32 tag) {
+                return this->cond_var.WaitForAddress(handle, address, tag);
+            }
+
+            void SignalConditionVariable(uintptr_t cv_key, int32_t count) {
+                return this->cond_var.Signal(cv_key, count);
+            }
+
+            Result WaitConditionVariable(KProcessAddress address, uintptr_t cv_key, u32 tag, s64 ns) {
+                return this->cond_var.Wait(address, cv_key, tag, ns);
+            }
+
             static void Switch(KProcess *cur_process, KProcess *next_process) {
                 /* Set the current process pointer. */
                 SetCurrentProcess(next_process);

libraries/libmesosphere/include/mesosphere/kern_k_thread.hpp

@@ -282,6 +282,15 @@ namespace ams::kern {
 
             constexpr uintptr_t GetConditionVariableKey() const { return this->condvar_key; }
 
+            constexpr void SetupForConditionVariableCompare(uintptr_t cv_key, int priority) {
+                this->condvar_key = cv_key;
+                this->priority    = priority;
+            }
+
+            void ClearConditionVariable() {
+                this->cond_var = nullptr;
+            }
+
             constexpr s32 GetIdealCore() const { return this->ideal_core_id; }
             constexpr s32 GetActiveCore() const { return this->core_id; }
             constexpr void SetActiveCore(s32 core) { this->core_id = core; }

libraries/libmesosphere/source/kern_k_condition_variable.cpp

@@ -0,0 +1,89 @@
+/*
+ * 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 {
+
+    namespace {
+
+        constinit KThread g_cv_compare_thread;
+
+    }
+
+    Result KConditionVariable::SignalToAddress(KProcessAddress addr) {
+        MESOSPHERE_UNIMPLEMENTED();
+    }
+
+    Result KConditionVariable::WaitForAddress(ams::svc::Handle handle, KProcessAddress addr, u32 value) {
+        MESOSPHERE_UNIMPLEMENTED();
+    }
+
+    KThread *KConditionVariable::SignalImpl(KThread *thread) {
+        MESOSPHERE_UNIMPLEMENTED();
+    }
+
+    void KConditionVariable::Signal(uintptr_t cv_key, s32 count) {
+        /* Prepare for signaling. */
+        constexpr int MaxThreads = 16;
+        KLinkedList<KThread> thread_list;
+        KThread *thread_array[MaxThreads];
+        int num_to_close = 0;
+
+        /* Perform signaling. */
+        int num_waiters = 0;
+        {
+            KScopedSchedulerLock sl;
+            g_cv_compare_thread.SetupForConditionVariableCompare(cv_key, -1);
+
+            auto it = this->tree.nfind(g_cv_compare_thread);
+            while ((it != this->tree.end()) && (count <= 0 || num_waiters < count) && (it->GetConditionVariableKey() == cv_key)) {
+                KThread *target_thread = std::addressof(*it);
+
+                if (KThread *thread = this->SignalImpl(target_thread); thread != nullptr) {
+                    if (num_to_close < MaxThreads) {
+                        thread_array[num_to_close++] = thread;
+                    } else {
+                        thread_list.push_back(*thread);
+                    }
+                }
+
+                it = this->tree.erase(it);
+                target_thread->ClearConditionVariable();
+                ++num_waiters;
+            }
+        }
+
+        /* Close threads in the array. */
+        for (auto i = 0; i < num_to_close; ++i) {
+            thread_array[i]->Close();
+        }
+
+        /* Close threads in the list. */
+        if (num_waiters > MaxThreads) {
+            auto it = thread_list.begin();
+            while (it != thread_list.end()) {
+                KThread *thread = std::addressof(*it);
+                thread->Close();
+                it = thread_list.erase(it);
+            }
+        }
+    }
+
+    Result KConditionVariable::Wait(KProcessAddress addr, uintptr_t key, u32 value, s64 timeout) {
+        MESOSPHERE_UNIMPLEMENTED();
+    }
+
+}

libraries/libmesosphere/source/svc/kern_svc_condition_variable.cpp

@@ -21,7 +21,9 @@ namespace ams::kern::svc {
 
     namespace {
 
-
+        void SignalProcessWideKey(uintptr_t cv_key, int32_t count) {
+            return GetCurrentProcess().SignalConditionVariable(util::AlignDown(cv_key, sizeof(u32)), count);
+        }
 
     }
 
@@ -32,7 +34,7 @@ namespace ams::kern::svc {
     }
 
     void SignalProcessWideKey64(ams::svc::Address cv_key, int32_t count) {
-        MESOSPHERE_PANIC("Stubbed SvcSignalProcessWideKey64 was called.");
+        return SignalProcessWideKey(cv_key, count);
     }
 
     /* ============================= 64From32 ABI ============================= */
@@ -42,7 +44,7 @@ namespace ams::kern::svc {
     }
 
     void SignalProcessWideKey64From32(ams::svc::Address cv_key, int32_t count) {
-        MESOSPHERE_PANIC("Stubbed SvcSignalProcessWideKey64From32 was called.");
+        return SignalProcessWideKey(cv_key, count);
     }
 
 }