samples/profiler/sample.c

   1 /*
   2  * Bare bones profiler showing how a profiler module should be structured.
   3  *
   4  * Compilation:
   5  * - Linux: gcc -fPIC -shared -o libmono-profiler-sample.so sample.c `pkg-config --cflags mono-2`
   6  * - OS X: clang -undefined suppress -flat_namespace -o mono-profiler-sample.dylib sample.c `pkg-config --cflags mono-2`
   7  *
   8  * If you're using a custom prefix for your Mono installation (e.g. /opt/mono),
   9  * pkg-config must be invoked like this: PKG_CONFIG_PATH=/opt/mono pkg-config --cflags mono-2
  10  *
  11  * Install the resulting shared library where the dynamic loader can find it,
  12  * e.g. /usr/local/lib or /opt/mono (custom prefix).
  13  *
  14  * To use the module: mono --profile=sample hello.exe
  15  */
  16
  17 #include <mono/metadata/profiler.h>
  18
  19 /*
  20  * Defining a type called _MonoProfiler will complete the opaque MonoProfiler
  21  * type, which is used throughout the profiler API.
  22  */
  23 struct _MonoProfiler {
  24         /* Handle obtained from mono_profiler_create (). */
  25         MonoProfilerHandle handle;
  26
  27         /* Counts the number of calls observed. */
  28         unsigned long long ncalls;
  29 };
  30
  31 /*
  32  * Use static storage for the profiler structure for simplicity. The structure
  33  * can be allocated dynamically as well, if needed.
  34  */
  35 static MonoProfiler profiler;
  36
  37 /*
  38  * Callback invoked after the runtime finishes shutting down. Managed code can
  39  * no longer run and most runtime services are unavailable.
  40  */
  41 static void
  42 sample_shutdown_end (MonoProfiler *prof)
  43 {
  44         printf ("Total number of calls: %llu\n", prof->ncalls);
  45 }
  46
  47 /*
  48  * Method enter callback invoked on entry to all instrumented methods.
  49  */
  50 static void
  51 sample_method_enter (MonoProfiler *prof, MonoMethod *method, MonoProfilerCallContext *ctx)
  52 {
  53         prof->ncalls++;
  54 }
  55
  56 /*
  57  * Filter callback that decides which methods to instrument and how.
  58  */
  59 static MonoProfilerCallInstrumentationFlags
  60 sample_call_instrumentation_filter (MonoProfiler *prof, MonoMethod *method)
  61 {
  62         return MONO_PROFILER_CALL_INSTRUMENTATION_ENTER;
  63 }
  64
  65 /*
  66  * The entry point function invoked by the Mono runtime.
  67  */
  68 void
  69 mono_profiler_init_sample (const char *desc)
  70 {
  71         profiler.handle = mono_profiler_create (&profiler);
  72
  73         mono_profiler_set_runtime_shutdown_end_callback (profiler.handle, sample_shutdown_end);
  74         mono_profiler_set_call_instrumentation_filter_callback (profiler.handle, sample_call_instrumentation_filter);
  75         mono_profiler_set_method_enter_callback (profiler.handle, sample_method_enter);
  76 }