[OpenMP][NFC] Encapsulate Devices.size()

[jdoerfert]

No description provided.

[llvmbot]

@llvm/pr-subscribers-openmp

Author: Johannes Doerfert (jdoerfert)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/74010.diff

2 Files Affected:

• (modified) openmp/libomptarget/include/PluginManager.h (+5)
• (modified) openmp/libomptarget/src/api.cpp (+8-16)

diff --git a/openmp/libomptarget/include/PluginManager.h b/openmp/libomptarget/include/PluginManager.h index 3a1c97fc52c95df..e9b5169510fc4dc 100644 --- a/openmp/libomptarget/include/PluginManager.h +++ b/openmp/libomptarget/include/PluginManager.h @@ -143,6 +143,11 @@ struct PluginManager { DelayedBinDesc.clear(); } + int getNumDevices() { + std::lock_guard<decltype(RTLsMtx)> Lock(RTLsMtx); + return Devices.size(); + } + private: bool RTLsLoaded = false; llvm::SmallVector<__tgt_bin_desc *> DelayedBinDesc; diff --git a/openmp/libomptarget/src/api.cpp b/openmp/libomptarget/src/api.cpp index e44421428adab44..cc4cca286df511e 100644 --- a/openmp/libomptarget/src/api.cpp +++ b/openmp/libomptarget/src/api.cpp @@ -28,13 +28,11 @@ EXTERN int omp_get_num_devices(void) { TIMESCOPE(); - PM->RTLsMtx.lock(); - size_t DevicesSize = PM->Devices.size(); - PM->RTLsMtx.unlock(); + size_t NumDevices = PM->getNumDevices(); - DP("Call to omp_get_num_devices returning %zd\n", DevicesSize); + DP("Call to omp_get_num_devices returning %zd\n", NumDevices); - return DevicesSize; + return NumDevices; } EXTERN int omp_get_device_num(void) { @@ -112,10 +110,8 @@ EXTERN int omp_target_is_present(const void *Ptr, int DeviceNum) { return true; } - PM->RTLsMtx.lock(); - size_t DevicesSize = PM->Devices.size(); - PM->RTLsMtx.unlock(); - if (DevicesSize <= (size_t)DeviceNum) { + size_t NumDevices = PM->getNumDevices(); + if (NumDevices <= (size_t)DeviceNum) { DP("Call to omp_target_is_present with invalid device ID, returning " "false\n"); return false; @@ -562,18 +558,14 @@ EXTERN void *omp_get_mapped_ptr(const void *Ptr, int DeviceNum) { return nullptr; } - if (DeviceNum == omp_get_initial_device()) { + size_t NumDevices = omp_get_initial_device(); + if (DeviceNum == NumDevices) { REPORT("Device %d is initial device, returning Ptr " DPxMOD ".\n", DeviceNum, DPxPTR(Ptr)); return const_cast<void *>(Ptr); } - int DevicesSize = omp_get_initial_device(); - { - std::lock_guard<std::mutex> LG(PM->RTLsMtx); - DevicesSize = PM->Devices.size(); - } - if (DevicesSize <= DeviceNum) { + if (NumDevices <= DeviceNum) { DP("DeviceNum %d is invalid, returning nullptr.\n", DeviceNum); return nullptr; } 

[jhuber6]

Unrelated, but wondering why we need a mutex for this when we could just have an atomic counter inside of the plugin manager.

[jdoerfert]

Unrelated, but wondering why we need a mutex for this when we could just have an atomic counter inside of the plugin manager.

Should work too. Feel free ;)