[OpenMP] Additional Information for Libomptarget Device Mappings

[jhuber6]

Summary

This patch adds additonal support for priting infromation from Libomptarget for already existing maps and printing the final data mapped on the device at device destruction.

[jhuber6]

Printing out tables at destruction only shows the mappings that are typically declared on the target. The others get deallocated at some point when the target data region ends. Also the messages for existing data mappings are helpful but they can get a bit verbose.

[jdoerfert]

openmp/libomptarget/src/device.cpp

55

early exit please.

65

please call dumpTargetPointerMappings, maybe pass the initial message as an argument or something but there is little gain in duplicating the logic.

[jhuber6]

openmp/libomptarget/src/device.cpp

65

Alright, I just want to clarify that you want this to print out only the persisting data on the device. The devices are stored in a global vector so they only deallocate at the end of the program.

222–223

Do you think there's a way to get the names of these mappings? I think it would be extremely helpful but would probably require adding something similar the ident_t that would outweigh the benefits.

[jhuber6]

Merged calls to a single function. Made it not print out if the table is empty.

[jdoerfert]

LGTM

openmp/libomptarget/src/device.cpp

222–223

We can, and should pass the name in, later.

openmp/libomptarget/src/device.cpp

 
 #include "device.h"
 #include "MemoryManager.h"
 #include "private.h"
 #include "rtl.h"
 
 #include <cassert>
 #include <climits>
+#include <cstdio>
 #include <string>
 
 /// Map between Device ID (i.e. openmp device id) and its DeviceTy.
 DevicesTy Devices;
 
 DeviceTy::DeviceTy(const DeviceTy &D)
     : DeviceID(D.DeviceID), RTL(D.RTL), RTLDeviceID(D.RTLDeviceID),
       IsInit(D.IsInit), InitFlag(), HasPendingGlobals(D.HasPendingGlobals),

 }
 
 DeviceTy::DeviceTy(RTLInfoTy *RTL)
     : DeviceID(-1), RTL(RTL), RTLDeviceID(-1), IsInit(false), InitFlag(),
       HasPendingGlobals(false), HostDataToTargetMap(), PendingCtorsDtors(),
       ShadowPtrMap(), DataMapMtx(), PendingGlobalsMtx(), ShadowMtx(),
       MemoryManager(nullptr) {}
 
-DeviceTy::~DeviceTy() = default;
+DeviceTy::~DeviceTy() {
+  if (DeviceID == -1 || getInfoLevel() < 1)
+    return;
+
+  dumpTargetPointerMappings(*this);
+}
 
 int DeviceTy::associatePtr(void *HstPtrBegin, void *TgtPtrBegin, int64_t Size) {
   DataMapMtx.lock();
 
   // Check if entry exists
   auto search = HostDataToTargetMap.find(HstPtrBeginTy{(uintptr_t)HstPtrBegin});
   if (search != HostDataToTargetMap.end()) {
     // Mapping already exists
     bool isValid = search->HstPtrEnd == (uintptr_t)HstPtrBegin + Size &&
                    search->TgtPtrBegin == (uintptr_t)TgtPtrBegin;
     DataMapMtx.unlock();
     if (isValid) {
       DP("Attempt to re-associate the same device ptr+offset with the same "
          "host ptr, nothing to do\n");
void *DeviceTy::getOrAllocTgtPtr(void *HstPtrBegin, void *HstPtrBase,
   if (lr.Flags.IsContained ||
       ((lr.Flags.ExtendsBefore || lr.Flags.ExtendsAfter) && IsImplicit)) {
     auto &HT = *lr.Entry;
     IsNew = false;
 
     if (UpdateRefCount)
       HT.incRefCount();
 
     uintptr_t tp = HT.TgtPtrBegin + ((uintptr_t)HstPtrBegin - HT.HstPtrBegin);
-    DP("Mapping exists%s with HstPtrBegin=" DPxMOD ", TgtPtrBegin=" DPxMOD ", "
-        "Size=%" PRId64 ",%s RefCount=%s\n", (IsImplicit ? " (implicit)" : ""),
-        DPxPTR(HstPtrBegin), DPxPTR(tp), Size,
-        (UpdateRefCount ? " updated" : ""),
+    INFO(DeviceID,
+         "Mapping exists%s with HstPtrBegin=" DPxMOD ", TgtPtrBegin=" DPxMOD
+         ", "
+         "Size=%" PRId64 ",%s RefCount=%s\n",
+         (IsImplicit ? " (implicit)" : ""), DPxPTR(HstPtrBegin), DPxPTR(tp),
+         Size, (UpdateRefCount ? " updated" : ""),
          HT.isRefCountInf() ? "INF" : std::to_string(HT.getRefCount()).c_str());
     rc = (void *)tp;
   } else if ((lr.Flags.ExtendsBefore || lr.Flags.ExtendsAfter) && !IsImplicit) {
     // Explicit extension of mapped data - not allowed.
     MESSAGE("explicit extension not allowed: host address specified is " DPxMOD
             " (%" PRId64 " bytes), but device allocation maps to host at "
             DPxMOD " (%" PRId64 " bytes)",
             DPxPTR(HstPtrBegin), Size, DPxPTR(lr.Entry->HstPtrBegin),
             lr.Entry->HstPtrEnd - lr.Entry->HstPtrBegin);

openmp/libomptarget/src/interface.cpp

 #include <cstdlib>
 #include <mutex>
 
 // Store target policy (disabled, mandatory, default)
 kmp_target_offload_kind_t TargetOffloadPolicy = tgt_default;
 std::mutex TargetOffloadMtx;
 
 ////////////////////////////////////////////////////////////////////////////////
-/// dump a table of all the host-target pointer pairs on failure
-static void dumpTargetPointerMappings() {
-  for (const auto &Device : Devices) {
-    fprintf(stderr, "Device %d:\n", Device.DeviceID);
-    fprintf(stderr, "%-18s %-18s %s\n", "Host Ptr", "Target Ptr", "Size (B)");
-    for (const auto &HostTargetMap : Device.HostDataToTargetMap) {
-      fprintf(stderr, DPxMOD " " DPxMOD " %lu\n",
-              DPxPTR(HostTargetMap.HstPtrBegin),
-              DPxPTR(HostTargetMap.TgtPtrBegin),
-              HostTargetMap.HstPtrEnd - HostTargetMap.HstPtrBegin);
-    }
-  }
-}
-
-////////////////////////////////////////////////////////////////////////////////
 /// manage the success or failure of a target construct
 static void HandleDefaultTargetOffload() {
   TargetOffloadMtx.lock();
   if (TargetOffloadPolicy == tgt_default) {
     if (omp_get_num_devices() > 0) {
       DP("Default TARGET OFFLOAD policy is now mandatory "
          "(devices were found)\n");
       TargetOffloadPolicy = tgt_mandatory;
case tgt_disabled:
       break;
     case tgt_default:
       FATAL_MESSAGE0(1, "default offloading policy must be switched to "
                         "mandatory or disabled");
       break;
     case tgt_mandatory:
       if (!success) {
         if (getInfoLevel() > 1)
-          dumpTargetPointerMappings();
+          for (const auto &Device : Devices)
+            dumpTargetPointerMappings(Device);
         else
-          FAILURE_MESSAGE("run with env LIBOMPTARGET_INFO>1 to dump tables\n");
+          FAILURE_MESSAGE("run with env LIBOMPTARGET_INFO>1 to dump host-target"
+                          "pointer maps\n");
 
         FATAL_MESSAGE0(1, "failure of target construct while offloading is mandatory");
       }
       break;
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////

openmp/libomptarget/src/private.h

 int __kmpc_get_target_offload(void) __attribute__((weak));
 #ifdef __cplusplus
 }
 #endif
 
 #define TARGET_NAME Libomptarget
 #define DEBUG_PREFIX GETNAME(TARGET_NAME)
 
+////////////////////////////////////////////////////////////////////////////////
+/// dump a table of all the host-target pointer pairs on failure
+static inline void dumpTargetPointerMappings(const DeviceTy &Device) {
+  if (Device.HostDataToTargetMap.empty())
+    return;
+
+  fprintf(stderr, "Device %d Host-Device Pointer Mappings:\n", Device.DeviceID);
+  fprintf(stderr, "%-18s %-18s %s\n", "Host Ptr", "Target Ptr", "Size (B)");
+  for (const auto &HostTargetMap : Device.HostDataToTargetMap) {
+    fprintf(stderr, DPxMOD " " DPxMOD " %lu\n",
+            DPxPTR(HostTargetMap.HstPtrBegin),
+            DPxPTR(HostTargetMap.TgtPtrBegin),
+            HostTargetMap.HstPtrEnd - HostTargetMap.HstPtrBegin);
+  }
+}
+
 #endif