iox-eclipse-iceoryx#2301 Add SpinLockSemaphore

elBoberido · Jul 24, 2024 · f70f1b5 · f70f1b5
1 parent 8736de4
commit f70f1b5
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Showing 2 changed files with 75 additions and 4 deletions.
diff --git a/iceoryx_posh/include/iceoryx_posh/internal/popo/building_blocks/condition_variable_data.hpp b/iceoryx_posh/include/iceoryx_posh/internal/popo/building_blocks/condition_variable_data.hpp
@@ -18,7 +18,10 @@
 #define IOX_POSH_POPO_BUILDING_BLOCKS_CONDITION_VARIABLE_DATA_HPP
 
 #include "iceoryx_posh/iceoryx_posh_types.hpp"
+#include "iceoryx_posh/internal/popo/building_blocks/locking_policy.hpp"
 #include "iceoryx_posh/internal/posh_error_reporting.hpp"
+#include "iox/deadline_timer.hpp"
+#include "iox/detail/adaptive_wait.hpp"
 #include "iox/unnamed_semaphore.hpp"
 
 #include <atomic>
@@ -27,6 +30,72 @@ namespace iox
 {
 namespace popo
 {
+class SpinLockSemaphore : public detail::SemaphoreInterface<SpinLockSemaphore>
+{
+  public:
+    SpinLockSemaphore()
+        : m_count(0)
+    {
+    }
+
+    ~SpinLockSemaphore()
+    {
+        m_to_be_destroyed = true;
+    }
+
+    expected<void, SemaphoreError> post()
+    {
+        std::lock_guard<SpinlockMutex> lock(spinlock);
+        ++m_count;
+        return ok();
+    }
+
+    expected<void, SemaphoreError> wait()
+    {
+        detail::adaptive_wait spinner;
+        spinner.wait_loop([this] { return !this->tryWait(); });
+        return ok();
+    }
+
+    expected<bool, SemaphoreError> tryWait()
+    {
+        std::lock_guard<SpinlockMutex> lock(spinlock);
+        if (m_to_be_destroyed == true)
+        {
+            return ok(true);
+        }
+        if (m_count > 0)
+        {
+            --m_count;
+            return ok(true);
+        }
+        return ok(false);
+    }
+
+    expected<SemaphoreWaitState, SemaphoreError> timedWait(const units::Duration& timeout)
+    {
+        iox::deadline_timer deadline_timer(timeout);
+        detail::adaptive_wait spinner;
+
+        auto ret_val = SemaphoreWaitState::TIMEOUT;
+        spinner.wait_loop([this, &deadline_timer, &ret_val] {
+            if (this->tryWait())
+            {
+                ret_val = SemaphoreWaitState::NO_TIMEOUT;
+                return false;
+            }
+            return !deadline_timer.hasExpired();
+        });
+
+        return ok(ret_val);
+    }
+
+  private:
+    std::atomic<int32_t> m_count{0};
+    std::atomic<bool> m_to_be_destroyed{false};
+    SpinlockMutex spinlock;
+};
+
 struct ConditionVariableData
 {
     ConditionVariableData() noexcept;
@@ -38,7 +107,7 @@ struct ConditionVariableData
     ConditionVariableData& operator=(ConditionVariableData&& rhs) = delete;
     ~ConditionVariableData() noexcept = default;
 
-    optional<UnnamedSemaphore> m_semaphore;
+    optional<SpinLockSemaphore> m_semaphore;
     RuntimeName_t m_runtimeName;
     std::atomic_bool m_toBeDestroyed{false};
     std::atomic_bool m_activeNotifications[MAX_NUMBER_OF_NOTIFIERS];

diff --git a/iceoryx_posh/source/popo/building_blocks/condition_variable_data.cpp b/iceoryx_posh/source/popo/building_blocks/condition_variable_data.cpp
@@ -30,9 +30,11 @@ ConditionVariableData::ConditionVariableData() noexcept
 ConditionVariableData::ConditionVariableData(const RuntimeName_t& runtimeName) noexcept
     : m_runtimeName(runtimeName)
 {
-    UnnamedSemaphoreBuilder().initialValue(0U).isInterProcessCapable(true).create(m_semaphore).or_else([](auto) {
-        IOX_REPORT_FATAL(PoshError::POPO__CONDITION_VARIABLE_DATA_FAILED_TO_CREATE_SEMAPHORE);
-    });
+    /// @todo iox-#2301 fix this with a proper spin-lock implementation
+    // UnnamedSemaphoreBuilder().initialValue(0U).isInterProcessCapable(true).create(m_semaphore).or_else([](auto) {
+    //     IOX_REPORT_FATAL(PoshError::POPO__CONDITION_VARIABLE_DATA_FAILED_TO_CREATE_SEMAPHORE);
+    // });
+    m_semaphore.emplace();
 
     for (auto& id : m_activeNotifications)
     {