fix mpi

mpi/gen_mpi.rb

@@ -1,11 +1,5 @@
 require_relative 'mpi_model'
 
-puts <<~EOF
-  #include <stdint.h>
-  #include <mpi.h>
-  #include "mpi_tracepoints.h"
-EOF
-
 def common_block(c, provider)
   params = c.parameters.collect(&:name)
   tp_params = c.parameters.collect do |p|
@@ -31,10 +25,10 @@ def common_block(c, provider)
   if c.has_return_type?
     puts <<EOF
   #{c.type} _retval;
-  _retval = P#{c.name}(#{params.join(', ')});
+  _retval = #{MPI_POINTER_NAMES[c]}(#{params.join(', ')});
 EOF
   else
-    puts "  P#{c.name}(#{params.join(', ')});"
+    puts "  #{MPI_POINTER_NAMES[c]}(#{params.join(', ')});"
   end
   c.tracepoint_parameters.each do |p|
     puts p.init if p.after?
@@ -50,14 +44,57 @@ def normal_wrapper(c, provider)
   puts <<~EOF
     #{c.decl} {
   EOF
+  puts "  _init_tracer();" if c.init?
+
   common_block(c, provider)
   puts <<~EOF
     }
 
   EOF
 end
 
+def define_and_find_mpi_symbols()
+
+  $mpi_commands.each { |c|
+    puts <<EOF
+#define #{MPI_POINTER_NAMES[c]} #{c.pointer_name}
+#{c.decl_pointer(c.pointer_type_name)};
+static #{c.pointer_type_name} #{MPI_POINTER_NAMES[c]} = (void *) 0x0;
+
+EOF
+}
+
+  puts <<EOF
+
+static void find_mpi_symbols(void * handle, int verbose) {
+EOF
+  $mpi_commands.each { |c|
+     puts <<EOF
+
+    #{MPI_POINTER_NAMES[c]} = (#{c.pointer_type_name})(intptr_t)dlsym(handle, "#{c.name}");
+    if (!#{MPI_POINTER_NAMES[c]} && verbose)
+      fprintf(stderr, "THAPI: Missing symbol #{c.name}!\\n");
+EOF
+  }
+
+puts <<EOF
+}
+
+EOF
+end
+
+puts <<~EOF
+  #include <stdint.h>
+  #include <mpi.h>
+  #include "mpi_tracepoints.h"
+  #include <dlfcn.h>
+  #include <pthread.h>
+EOF
+
+define_and_find_mpi_symbols
+
+puts File::read(File.join(SRC_DIR,"tracer_mpi_helpers.include.c"))
+
 $mpi_commands.each do |c|
-  next if c.name.start_with?("PMPI")
   normal_wrapper(c, :lttng_ust_mpi)
 end

mpi/mpi_model.rb

@@ -25,7 +25,7 @@
 
 mpi_funcs_e = $mpi_api["functions"]
 
-INIT_FUNCTIONS=/None/
+INIT_FUNCTIONS=/MPI_Init|MPI_Init_thread/
 
 $mpi_meta_parameters = YAML::load_file(File.join(SRC_DIR, "mpi_meta_parameters.yaml"))
 $mpi_meta_parameters.fetch("meta_parameters",[]).each  { |func, list|
@@ -39,7 +39,7 @@
 }
 
 def upper_snake_case(str)
-  str.gsub(/([A-Z][A-Z0-9]*)/, '_\1').upcase
+  str.gsub(/([a-z][a-z0-9]*)/, '_\1').upcase
 end
 
 MPI_POINTER_NAMES = $mpi_commands.collect { |c|

mpi/tracer_mpi_helpers.include.c

@@ -0,0 +1,48 @@
+static pthread_once_t _init = PTHREAD_ONCE_INIT;
+static __thread volatile int in_init = 0;
+static volatile unsigned int _initialized = 0;
+
+static void _load_tracer(void) {
+  char *s = NULL;
+  void *handle = NULL;
+  int verbose = 0;
+
+  s = getenv("LTTNG_UST_MPI_LIBMPI_LOADER");
+  if (s)
+    handle = dlopen(s, RTLD_LAZY | RTLD_LOCAL | RTLD_DEEPBIND);
+  else
+    handle = dlopen("libmpi.so", RTLD_LAZY | RTLD_LOCAL | RTLD_DEEPBIND);
+  if (handle) {
+    void* ptr = dlsym(handle, "MPI_Init");
+    if (ptr == (void*)&MPI_Init) { //opening oneself
+      dlclose(handle);
+      handle = NULL;
+    }
+  }
+
+  if( !handle ) {
+    fprintf(stderr, "THAPI: Failure: could not load MPI library!\n");
+    exit(1);
+  }
+
+  s = getenv("LTTNG_UST_MPI_VERBOSE");
+  if (s)
+    verbose = 1;
+
+  find_mpi_symbols(handle, verbose);
+}
+
+static inline void _init_tracer(void) {
+  if( __builtin_expect (_initialized, 1) )
+    return;
+  /* Avoid reentrancy */
+  if (!in_init) {
+    in_init=1;
+    __sync_synchronize();
+    pthread_once(&_init, _load_tracer);
+    __sync_synchronize();
+    in_init=0;
+  }
+  _initialized = 1;
+}
+