Reverse logic of context tracking enablement from #1927 (#1971)

In this commit it disabled by default and can be enabled via
`RCCL_ENABLE_CONTEXT_TRACKING=1` for both (CDNA, RDNA)
Original PR https://github.com/ROCm/rccl/pull/1927

src/init.cc

@@ -246,6 +246,7 @@ RCCL_PARAM(EnableProxyTrace, "ENABLE_PROXY_TRACE", 0);
 
 RCCL_PARAM(KernelCollTraceEnable, "KERNEL_COLL_TRACE_ENABLE", 0);
 RCCL_PARAM(KernelCollTraceThreadEnable, "KERNEL_COLL_TRACE_THREAD_ENABLE", 0);
+RCCL_PARAM(EnableContextTracking, "ENABLE_CONTEXT_TRACKING", 0);
 
 #ifdef ENABLE_COLLTRACE
 // Should be in sync with 'ALL_COLLS' in Generator.cmake
@@ -532,8 +533,8 @@ static ncclResult_t commFree(ncclComm_t comm) {
   NCCLCHECK(ncclProfilerPluginFinalize(comm));
   NCCLCHECK(ncclNetFinalize(comm));
   // Disable until we validate NCCL_LAUNCH_IMPLICIT_ORDER support.
-  // but enable for Radeon due to big impact on performance
-  if (rcclNeedEnableContextTrack(comm->cudaDev)) {
+  // but can be enabled via environment variable
+  if (rcclParamEnableContextTracking() == 1) {
     ncclCudaContextDrop(comm->context);
     INFO(NCCL_INIT, "cudaDev %d context tracking destroyed", comm->cudaDev);
   }
@@ -633,8 +634,8 @@ static ncclResult_t commAlloc(struct ncclComm* comm, struct ncclComm* parent, in
   CUDACHECK(cudaGetDevice(&comm->cudaDev));
 
   // Disable until we validate NCCL_LAUNCH_IMPLICIT_ORDER support.
-  // but enable for Radeon due to big impact on performance
-  if (rcclNeedEnableContextTrack(comm->cudaDev)) {
+  // but can be enabled via environment variable
+  if (rcclParamEnableContextTracking() == 1) {
     NCCLCHECK(ncclCudaContextTrack(&comm->context));
     INFO(NCCL_INIT, "cudaDev %d context tracking created", comm->cudaDev);
   }