[Openmp-commits] [PATCH] D132885: [libomptarget] Deprecate old method for setting the tripcount

[Joseph Huber via Phabricator via Openmp-commits]

jhuber6 created this revision.
jhuber6 added reviewers: jdoerfert, tianshilei1992, ye-luo, ronlieb, JonChesterfield.
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Previously, the tripcount was set by a push call. We moved away from
this with the new interface that added the tripcount to the kernel
arguments struct, but kept around the old interface for legacy purposes
for the LLVM 15 release. This patch removes the support for the legacy
method.

This removes the support for the old method, but does not break
backwards compatibility. This will result in applications using the old
interface being slower when run on the device.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D132885

Files:
  openmp/libomptarget/include/device.h
  openmp/libomptarget/src/LegacyAPI.cpp
  openmp/libomptarget/src/omptarget.cpp


Index: openmp/libomptarget/src/omptarget.cpp
===================================================================
--- openmp/libomptarget/src/omptarget.cpp
+++ openmp/libomptarget/src/omptarget.cpp
@@ -1130,26 +1130,6 @@
   return nullptr;
 }
 
-/// Get loop trip count
-/// FIXME: This function will not work right if calling
-/// __kmpc_push_target_tripcount_mapper in one thread but doing offloading in
-/// another thread, which might occur when we call task yield.
-uint64_t getLoopTripCount(int64_t DeviceId) {
-  DeviceTy &Device = *PM->Devices[DeviceId];
-  uint64_t LoopTripCount = 0;
-
-  {
-    std::lock_guard<std::mutex> TblMapLock(PM->TblMapMtx);
-    auto I = Device.LoopTripCnt.find(__kmpc_global_thread_num(NULL));
-    if (I != Device.LoopTripCnt.end()) {
-      LoopTripCount = I->second;
-      Device.LoopTripCnt.erase(I);
-    }
-  }
-
-  return LoopTripCount;
-}
-
 /// A class manages private arguments in a target region.
 class PrivateArgumentManagerTy {
   /// A data structure for the information of first-private arguments. We can
@@ -1512,8 +1492,6 @@
   }
   assert(TargetTable && "Global data has not been mapped\n");
 
-  // FIXME: Use legacy tripcount method if it is '-1'.
-  Tripcount = Tripcount == -1UL ? getLoopTripCount(DeviceId) : Tripcount;
   DP("loop trip count is %" PRIu64 ".\n", Tripcount);
 
   // We need to keep bases and offsets separate. Sometimes (e.g. in OpenCL) we
Index: openmp/libomptarget/src/LegacyAPI.cpp
===================================================================
--- openmp/libomptarget/src/LegacyAPI.cpp
+++ openmp/libomptarget/src/LegacyAPI.cpp
@@ -77,7 +77,7 @@
                                map_var_info_t *ArgNames, void **ArgMappers) {
   TIMESCOPE_WITH_IDENT(Loc);
   __tgt_kernel_arguments KernelArgs{
-      1, ArgNum, ArgsBase, Args, ArgSizes, ArgTypes, ArgNames, ArgMappers, -1};
+      1, ArgNum, ArgsBase, Args, ArgSizes, ArgTypes, ArgNames, ArgMappers, 0};
   return __tgt_target_kernel(Loc, DeviceId, -1, -1, HostPtr, &KernelArgs);
 }
 
@@ -120,7 +120,7 @@
   TIMESCOPE_WITH_IDENT(Loc);
 
   __tgt_kernel_arguments KernelArgs{
-      1, ArgNum, ArgsBase, Args, ArgSizes, ArgTypes, ArgNames, ArgMappers, -1};
+      1, ArgNum, ArgsBase, Args, ArgSizes, ArgTypes, ArgNames, ArgMappers, 0};
   return __tgt_target_kernel(Loc, DeviceId, NumTeams, ThreadLimit, HostPtr,
                              &KernelArgs);
 }
@@ -165,17 +165,6 @@
 EXTERN void __kmpc_push_target_tripcount_mapper(ident_t *Loc, int64_t DeviceId,
                                                 uint64_t LoopTripcount) {
   TIMESCOPE_WITH_IDENT(Loc);
-  if (checkDeviceAndCtors(DeviceId, Loc)) {
-    DP("Not offloading to device %" PRId64 "\n", DeviceId);
-    return;
-  }
-
-  DP("__kmpc_push_target_tripcount(%" PRId64 ", %" PRIu64 ")\n", DeviceId,
-     LoopTripcount);
-  PM->TblMapMtx.lock();
-  PM->Devices[DeviceId]->LoopTripCnt[__kmpc_global_thread_num(NULL)] =
-      LoopTripcount;
-  PM->TblMapMtx.unlock();
 }
 
 EXTERN void __kmpc_push_target_tripcount(int64_t DeviceId,
Index: openmp/libomptarget/include/device.h
===================================================================
--- openmp/libomptarget/include/device.h
+++ openmp/libomptarget/include/device.h
@@ -334,10 +334,6 @@
 
   std::mutex PendingGlobalsMtx, ShadowMtx;
 
-  // NOTE: Once libomp gains full target-task support, this state should be
-  // moved into the target task in libomp.
-  std::map<int32_t, uint64_t> LoopTripCnt;
-
   DeviceTy(RTLInfoTy *RTL);
   // DeviceTy is not copyable
   DeviceTy(const DeviceTy &D) = delete;


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