Merge pull request #2230 from pbalcer/check-xpti-enabled

don't call xpti if there are no subscribers

Author: pbalcer

CMakeLists.txt

@@ -137,7 +137,7 @@ if(UR_ENABLE_TRACING)
 
     if (UR_BUILD_XPTI_LIBS)
         # fetch xpti proxy library for the tracing layer
-        FetchContentSparse_Declare(xpti https://github.com/intel/llvm.git "sycl-nightly/20230703" "xpti")
+        FetchContentSparse_Declare(xpti https://github.com/intel/llvm.git "nightly-2024-10-22" "xpti")
         FetchContent_MakeAvailable(xpti)
 
         # set -fPIC for xpti since we are linking it with a shared library
@@ -149,7 +149,7 @@ if(UR_ENABLE_TRACING)
         set(XPTI_DIR ${xpti_SOURCE_DIR})
         set(XPTI_ENABLE_TESTS OFF CACHE INTERNAL "Turn off xptifw tests")
 
-        FetchContentSparse_Declare(xptifw https://github.com/intel/llvm.git "sycl-nightly/20230703" "xptifw")
+        FetchContentSparse_Declare(xptifw https://github.com/intel/llvm.git "nightly-2024-10-22" "xptifw")
 
         FetchContent_MakeAvailable(xptifw)
 

examples/collector/collector.cpp

@@ -125,8 +125,7 @@ XPTI_CALLBACK_API void xptiTraceInit(unsigned int major_version,
         return;
     }
     if (std::string_view(stream_name) != UR_STREAM_NAME) {
-        std::cout << "Invalid stream name: " << stream_name << ". Expected "
-                  << UR_STREAM_NAME << ". Aborting." << std::endl;
+        // we expect ur.call, but this can also be xpti.framework.
         return;
     }
 

source/loader/layers/tracing/ur_tracing_layer.cpp

@@ -15,6 +15,7 @@
 #include "xpti/xpti_data_types.h"
 #include "xpti/xpti_trace_framework.h"
 #include <atomic>
+#include <cstdint>
 #include <optional>
 #include <sstream>
 
@@ -59,6 +60,12 @@ void context_t::notify(uint16_t trace_type, uint32_t id, const char *name,
 }
 
 uint64_t context_t::notify_begin(uint32_t id, const char *name, void *args) {
+    // we use UINT64_MAX as a special value that means "tracing disabled",
+    // so that we don't have to repeat this check in notify_end.
+    if (!xptiCheckTraceEnabled(call_stream_id)) {
+        return UINT64_MAX;
+    }
+
     if (auto loc = codelocData.get_codeloc()) {
         xpti::payload_t payload =
             xpti::payload_t(loc->functionName, loc->sourceFile, loc->lineNumber,
@@ -77,6 +84,10 @@ uint64_t context_t::notify_begin(uint32_t id, const char *name, void *args) {
 
 void context_t::notify_end(uint32_t id, const char *name, void *args,
                            ur_result_t *resultp, uint64_t instance) {
+    if (instance == UINT64_MAX) { // tracing disabled
+        return;
+    }
+
     notify((uint16_t)xpti::trace_point_type_t::function_with_args_end, id, name,
            args, resultp, instance);
 }

test/layers/tracing/test_collector.cpp

@@ -49,8 +49,7 @@ XPTI_CALLBACK_API void xptiTraceInit(unsigned int major_version,
         return;
     }
     if (std::string_view(stream_name) != UR_STREAM_NAME) {
-        std::cout << "Invalid stream name: " << stream_name << ". Expected "
-                  << UR_STREAM_NAME << ". Aborting." << std::endl;
+        // we expect ur.call, but this can also be xpti.framework.
         return;
     }