[Openmp-commits] [PATCH] D95786: [OpenMP] Fix seg fault in libomptarget when using Info with multiple threads

[Joseph Huber via Phabricator via Openmp-commits]

jhuber6 created this revision.
jhuber6 added a reviewer: jdoerfert.
jhuber6 added a project: OpenMP.
Herald added subscribers: guansong, yaxunl.
jhuber6 requested review of this revision.
Herald added subscribers: openmp-commits, sstefan1.

One option for the LIBOMPTARGET_INFO environment variable is to print the current status of the device's data mappings. These are a shared resource among threads so this needs to be protected when using multiple streams.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D95786

Files:
  openmp/libomptarget/src/interface.cpp
  openmp/libomptarget/src/private.h


Index: openmp/libomptarget/src/private.h
===================================================================
--- openmp/libomptarget/src/private.h
+++ openmp/libomptarget/src/private.h
@@ -99,7 +99,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 /// dump a table of all the host-target pointer pairs on failure
 static inline void dumpTargetPointerMappings(const ident_t *Loc,
-                                             const DeviceTy &Device) {
+                                             DeviceTy &Device) {
   if (Device.HostDataToTargetMap.empty())
     return;
 
@@ -109,6 +109,7 @@
        Kernel.getFilename(), Kernel.getLine(), Kernel.getColumn());
   INFO(OMP_INFOTYPE_ALL, Device.DeviceID, "%-18s %-18s %s %s %s\n", "Host Ptr",
        "Target Ptr", "Size (B)", "RefCount", "Declaration");
+  Device.DataMapMtx.lock();
   for (const auto &HostTargetMap : Device.HostDataToTargetMap) {
     SourceInfo Info(HostTargetMap.HstPtrName);
     INFO(OMP_INFOTYPE_ALL, Device.DeviceID,
@@ -118,6 +119,7 @@
          HostTargetMap.getRefCount(), Info.getName(), Info.getFilename(),
          Info.getLine(), Info.getColumn());
   }
+  Device.DataMapMtx.unlock();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
Index: openmp/libomptarget/src/interface.cpp
===================================================================
--- openmp/libomptarget/src/interface.cpp
+++ openmp/libomptarget/src/interface.cpp
@@ -58,7 +58,7 @@
   case tgt_mandatory:
     if (!success) {
       if (getInfoLevel() & OMP_INFOTYPE_DUMP_TABLE)
-        for (const auto &Device : PM->Devices)
+        for (auto &Device : PM->Devices)
           dumpTargetPointerMappings(loc, Device);
       else
         FAILURE_MESSAGE("Run with LIBOMPTARGET_DEBUG=%d to dump host-target "
@@ -76,7 +76,7 @@
           1, "failure of target construct while offloading is mandatory");
     } else {
       if (getInfoLevel() & OMP_INFOTYPE_DUMP_TABLE)
-        for (const auto &Device : PM->Devices)
+        for (auto &Device : PM->Devices)
           dumpTargetPointerMappings(loc, Device);
     }
     break;


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