[OPENMP][AMDGCN] Improvements to print_kernel_trace (bit mask)

[ronlieb]

Summary

allow bit masking to select various trace features.
  bit 0 => Launch tracing           (stderr)
  bit 1 => timing of runtime        (stdout)
  bit 2 => detailed launch tracing  (stderr)
  bit 3 => timing goes to stdout instead of stderr

  example: LIBOMPTARGET_KERNEL_TRACE=7     does it all
           LIBOMPTARGET_KERNEL_TRACE=5     Launch + details
           LIBOMPTARGET_KERNEL_TRACE=2     timings + launch to stderr
           LIBOMPTARGET_KERNEL_TRACE=10    timings + launch to stdout

[JonChesterfield]

Enums are a good idea here, thanks.

[jdoerfert]

openmp/libomptarget/plugins/amdgpu/src/print_tracing.h

2

license missing

14

This doesn't seem clang formated.

[ronlieb]

added license, and clang-format-ed new file

[pdhaliwal]

Looks good to me. Thanks!

[ronlieb]

@jdoerfert acceptable?

[JonChesterfield]

Not Johannes, but probably yes. Wonder if we're missing the license header on other files in this plugin.

The int print_kernel_trace is a wide contract - it suggests it might be toggled from anywhere. Which it isn't. We should change to something more like the other debug/env wrapper and use a function call to access. Independent of this review - just reminded of it by seeing the raw int declaration.

openmp/libomptarget/plugins/amdgpu/src/print_tracing.h

+//===--- print_tracing.h - OpenMP interface definitions -------- AMDGPU -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBOMPTARGET_PLUGINS_AMGGPU_SRC_PRINT_TRACING_H_INCLUDED
+#define LIBOMPTARGET_PLUGINS_AMGGPU_SRC_PRINT_TRACING_H_INCLUDED
+
+enum PrintTraceControlBits {
+  LAUNCH = 1,          // print a message to stderr for each kernel launch
+  RTL_TIMING = 2,      // Print timing info around each RTL step
+  STARTUP_DETAILS = 4, // Details around loading up kernel
+  RTL_TO_STDOUT = 8    // Redirect RTL tracing to stdout
+};
+
+extern int print_kernel_trace; // set by environment variable
+
+#endif

openmp/libomptarget/plugins/amdgpu/src/rtl.cpp

 #include "atmi_interop_hsa.h"
 #include "atmi_runtime.h"
 
 #include "internal.h"
 
 #include "Debug.h"
 #include "get_elf_mach_gfx_name.h"
 #include "omptargetplugin.h"
+#include "print_tracing.h"
 
 #include "llvm/Frontend/OpenMP/OMPGridValues.h"
 
 #ifndef TARGET_NAME
 #define TARGET_NAME AMDHSA
 #endif
 #define DEBUG_PREFIX "Target " GETNAME(TARGET_NAME) " RTL"
 
int32_t __tgt_rtl_init_device(int device_id) {
   err = hsa_agent_get_info(agent, (hsa_agent_info_t)HSA_AGENT_INFO_NAME,
                            (void *)GetInfoName);
   if (err)
     DeviceInfo.GPUName[device_id] = "--unknown gpu--";
   else {
     DeviceInfo.GPUName[device_id] = GetInfoName;
   }
 
-  if (print_kernel_trace == 4)
+  if (print_kernel_trace & STARTUP_DETAILS)
     fprintf(stderr, "Device#%-2d CU's: %2d %s\n", device_id,
             DeviceInfo.ComputeUnits[device_id],
             DeviceInfo.GPUName[device_id].c_str());
 
   // Query attributes to determine number of threads/block and blocks/grid.
   uint16_t workgroup_max_dim[3];
   err = hsa_agent_get_info(agent, HSA_AGENT_INFO_WORKGROUP_MAX_DIM,
                            &workgroup_max_dim);
void getLaunchVals(int &threadsPerGroup, int &num_groups, int ConstWGSize,
                    int32_t device_id) {
 
   int Max_Teams = DeviceInfo.EnvMaxTeamsDefault > 0
                       ? DeviceInfo.EnvMaxTeamsDefault
                       : DeviceInfo.NumTeams[device_id];
   if (Max_Teams > DeviceInfo.HardTeamLimit)
     Max_Teams = DeviceInfo.HardTeamLimit;
 
-  if (print_kernel_trace == 4) {
+  if (print_kernel_trace & STARTUP_DETAILS) {
     fprintf(stderr, "RTLDeviceInfoTy::Max_Teams: %d\n",
             RTLDeviceInfoTy::Max_Teams);
     fprintf(stderr, "Max_Teams: %d\n", Max_Teams);
     fprintf(stderr, "RTLDeviceInfoTy::Warp_Size: %d\n",
             RTLDeviceInfoTy::Warp_Size);
     fprintf(stderr, "RTLDeviceInfoTy::Max_WG_Size: %d\n",
             RTLDeviceInfoTy::Max_WG_Size);
     fprintf(stderr, "RTLDeviceInfoTy::Default_WG_Size: %d\n",
if (thread_limit > 0) {
     }
   }
   // check flat_max_work_group_size attr here
   if (threadsPerGroup > ConstWGSize) {
     threadsPerGroup = ConstWGSize;
     DP("Reduced threadsPerGroup to flat-attr-group-size limit %d\n",
        threadsPerGroup);
   }
-  if (print_kernel_trace == 4)
+  if (print_kernel_trace & STARTUP_DETAILS)
     fprintf(stderr, "threadsPerGroup: %d\n", threadsPerGroup);
   DP("Preparing %d threads\n", threadsPerGroup);
 
   // Set default num_groups (teams)
   if (DeviceInfo.EnvTeamLimit > 0)
     num_groups = (Max_Teams < DeviceInfo.EnvTeamLimit)
                      ? Max_Teams
                      : DeviceInfo.EnvTeamLimit;
   else
     num_groups = Max_Teams;
   DP("Set default num of groups %d\n", num_groups);
 
-  if (print_kernel_trace == 4) {
+  if (print_kernel_trace & STARTUP_DETAILS) {
     fprintf(stderr, "num_groups: %d\n", num_groups);
     fprintf(stderr, "num_teams: %d\n", num_teams);
   }
 
   // Reduce num_groups if threadsPerGroup exceeds RTLDeviceInfoTy::Max_WG_Size
   // This reduction is typical for default case (no thread_limit clause).
   // or when user goes crazy with num_teams clause.
   // FIXME: We cant distinguish between a constant or variable thread limit.
   // So we only handle constant thread_limits.
   if (threadsPerGroup >
       RTLDeviceInfoTy::Default_WG_Size) //  256 < threadsPerGroup <= 1024
     // Should we round threadsPerGroup up to nearest RTLDeviceInfoTy::Warp_Size
     // here?
     num_groups = (Max_Teams * RTLDeviceInfoTy::Max_WG_Size) / threadsPerGroup;
 
   // check for num_teams() clause
   if (num_teams > 0) {
     num_groups = (num_teams < num_groups) ? num_teams : num_groups;
   }
-  if (print_kernel_trace == 4) {
+  if (print_kernel_trace & STARTUP_DETAILS) {
     fprintf(stderr, "num_groups: %d\n", num_groups);
     fprintf(stderr, "DeviceInfo.EnvNumTeams %d\n", DeviceInfo.EnvNumTeams);
     fprintf(stderr, "DeviceInfo.EnvTeamLimit %d\n", DeviceInfo.EnvTeamLimit);
   }
 
   if (DeviceInfo.EnvNumTeams > 0) {
     num_groups = (DeviceInfo.EnvNumTeams < num_groups) ? DeviceInfo.EnvNumTeams
                                                        : num_groups;
if (num_teams <= 0) {
            "threads per block %d\n",
            num_groups, loop_tripcount, threadsPerGroup);
       }
     } else {
       num_groups = num_teams;
     }
     if (num_groups > Max_Teams) {
       num_groups = Max_Teams;
-      if (print_kernel_trace == 4)
+      if (print_kernel_trace & STARTUP_DETAILS)
         fprintf(stderr, "Limiting num_groups %d to Max_Teams %d \n", num_groups,
                 Max_Teams);
     }
     if (num_groups > num_teams && num_teams > 0) {
       num_groups = num_teams;
-      if (print_kernel_trace == 4)
+      if (print_kernel_trace & STARTUP_DETAILS)
         fprintf(stderr, "Limiting num_groups %d to clause num_teams %d \n",
                 num_groups, num_teams);
     }
   }
 
   // num_teams clause always honored, no matter what, unless DEFAULT is active.
   if (num_teams > 0) {
     num_groups = num_teams;
     // Cap num_groups to EnvMaxTeamsDefault if set.
     if (DeviceInfo.EnvMaxTeamsDefault > 0 &&
         num_groups > DeviceInfo.EnvMaxTeamsDefault)
       num_groups = DeviceInfo.EnvMaxTeamsDefault;
   }
-  if (print_kernel_trace == 4) {
+  if (print_kernel_trace & STARTUP_DETAILS) {
     fprintf(stderr, "threadsPerGroup: %d\n", threadsPerGroup);
     fprintf(stderr, "num_groups: %d\n", num_groups);
     fprintf(stderr, "loop_tripcount: %ld\n", loop_tripcount);
   }
   DP("Final %d num_groups and %d threadsPerGroup\n", num_groups,
      threadsPerGroup);
 }
 
int32_t __tgt_rtl_run_target_team_region_locked(
   getLaunchVals(threadsPerGroup, num_groups, KernelInfo->ConstWGSize,
                 KernelInfo->ExecutionMode, DeviceInfo.EnvTeamLimit,
                 DeviceInfo.EnvNumTeams,
                 num_teams,      // From run_region arg
                 thread_limit,   // From run_region arg
                 loop_tripcount, // From run_region arg
                 KernelInfo->device_id);
 
-  if (print_kernel_trace >= 1)
+  if (print_kernel_trace >= LAUNCH) {
     // enum modes are SPMD, GENERIC, NONE 0,1,2
-    fprintf(stderr,
+    // if doing rtl timing, print to stderr, unless stdout requested.
+    bool traceToStdout = print_kernel_trace & (RTL_TO_STDOUT | RTL_TIMING);
+    fprintf(traceToStdout ? stdout : stderr,
             "DEVID:%2d SGN:%1d ConstWGSize:%-4d args:%2d teamsXthrds:(%4dX%4d) "
             "reqd:(%4dX%4d) n:%s\n",
             device_id, KernelInfo->ExecutionMode, KernelInfo->ConstWGSize,
             arg_num, num_groups, threadsPerGroup, num_teams, thread_limit,
             KernelInfo->Name);
+  }
 
   // Run on the device.
   {
     hsa_queue_t *queue = DeviceInfo.HSAQueues[device_id];
     uint64_t packet_id = acquire_available_packet_id(queue);
 
     const uint32_t mask = queue->size - 1; // size is a power of 2
     hsa_kernel_dispatch_packet_t *packet =