Separate the procfs tapset

1 files changed, 1 insertions, 499 deletions

diff --git a/tapsets.cxx b/tapsets.cxx
index e6d641bd..86b2aa53 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -4270,15 +4270,6 @@ dwflpp::query_modules(base_query *q)
   iterate_over_modules(&query_module, q);
 }
 
-struct var_expanding_visitor: public update_visitor
-{
-  static unsigned tick;
-  stack<functioncall**> target_symbol_setter_functioncalls;
-
-  var_expanding_visitor() {}
-  void visit_assignment (assignment* e);
-};
-
 
 struct dwarf_var_expanding_visitor: public var_expanding_visitor
 {
@@ -8550,488 +8541,6 @@ kprobe_builder::build(systemtap_session & sess,
 
 
 // ------------------------------------------------------------------------
-// procfs file derived probes
-// ------------------------------------------------------------------------
-
-
-static string TOK_PROCFS("procfs");
-static string TOK_READ("read");
-static string TOK_WRITE("write");
-
-struct procfs_derived_probe: public derived_probe
-{
-  string path;
-  bool write;
-  bool target_symbol_seen;
-
-  procfs_derived_probe (systemtap_session &, probe* p, probe_point* l, string ps, bool w);
-  void join_group (systemtap_session& s);
-};
-
-
-struct procfs_probe_set
-{
-  procfs_derived_probe* read_probe;
-  procfs_derived_probe* write_probe;
-
-  procfs_probe_set () : read_probe (NULL), write_probe (NULL) {}
-};
-
-
-struct procfs_derived_probe_group: public generic_dpg<procfs_derived_probe>
-{
-private:
-  map<string, procfs_probe_set*> probes_by_path;
-  typedef map<string, procfs_probe_set*>::iterator p_b_p_iterator;
-  bool has_read_probes;
-  bool has_write_probes;
-
-public:
-  procfs_derived_probe_group () :
-    has_read_probes(false), has_write_probes(false) {}
-
-  void enroll (procfs_derived_probe* probe);
-  void emit_module_decls (systemtap_session& s);
-  void emit_module_init (systemtap_session& s);
-  void emit_module_exit (systemtap_session& s);
-};
-
-
-struct procfs_var_expanding_visitor: public var_expanding_visitor
-{
-  procfs_var_expanding_visitor(systemtap_session& s, const string& pn,
-                               string path, bool write_probe):
-    sess (s), probe_name (pn), path (path), write_probe (write_probe),
-    target_symbol_seen (false) {}
-
-  systemtap_session& sess;
-  string probe_name;
-  string path;
-  bool write_probe;
-  bool target_symbol_seen;
-
-  void visit_target_symbol (target_symbol* e);
-};
-
-
-procfs_derived_probe::procfs_derived_probe (systemtap_session &s, probe* p,
-					    probe_point* l, string ps, bool w):
-  derived_probe(p, l), path(ps), write(w), target_symbol_seen(false)
-{
-  // Expand local variables in the probe body
-  procfs_var_expanding_visitor v (s, name, path, write);
-  this->body = v.require (this->body);
-  target_symbol_seen = v.target_symbol_seen;
-}
-
-
-void
-procfs_derived_probe::join_group (systemtap_session& s)
-{
-  if (! s.procfs_derived_probes)
-    s.procfs_derived_probes = new procfs_derived_probe_group ();
-  s.procfs_derived_probes->enroll (this);
-}
-
-
-void
-procfs_derived_probe_group::enroll (procfs_derived_probe* p)
-{
-  procfs_probe_set *pset;
-
-  if (probes_by_path.count(p->path) == 0)
-    {
-      pset = new procfs_probe_set;
-      probes_by_path[p->path] = pset;
-    }
-  else
-    {
-      pset = probes_by_path[p->path];
-
-      // You can only specify 1 read and 1 write probe.
-      if (p->write && pset->write_probe != NULL)
-	throw semantic_error("only one write procfs probe can exist for procfs path \"" + p->path + "\"");
-      else if (! p->write && pset->read_probe != NULL)
-	throw semantic_error("only one read procfs probe can exist for procfs path \"" + p->path + "\"");
-
-      // XXX: multiple writes should be acceptable
-    }
-
-  if (p->write)
-  {
-    pset->write_probe = p;
-    has_write_probes = true;
-  }
-  else
-  {
-    pset->read_probe = p;
-    has_read_probes = true;
-  }
-}
-
-
-void
-procfs_derived_probe_group::emit_module_decls (systemtap_session& s)
-{
-  if (probes_by_path.empty())
-    return;
-
-  s.op->newline() << "/* ---- procfs probes ---- */";
-  s.op->newline() << "#include \"procfs.c\"";
-
-  // Emit the procfs probe data list
-  s.op->newline() << "static struct stap_procfs_probe {";
-  s.op->newline(1)<< "const char *path;";
-  s.op->newline() << "const char *read_pp;";
-  s.op->newline() << "void (*read_ph) (struct context*);";
-  s.op->newline() << "const char *write_pp;";
-  s.op->newline() << "void (*write_ph) (struct context*);";
-  s.op->newline(-1) << "} stap_procfs_probes[] = {";
-  s.op->indent(1);
-
-  for (p_b_p_iterator it = probes_by_path.begin(); it != probes_by_path.end();
-       it++)
-  {
-      procfs_probe_set *pset = it->second;
-
-      s.op->newline() << "{";
-      s.op->line() << " .path=" << lex_cast_qstring (it->first) << ",";
-
-      if (pset->read_probe != NULL)
-        {
-	  s.op->line() << " .read_pp="
-		       << lex_cast_qstring (*pset->read_probe->sole_location())
-		       << ",";
-	  s.op->line() << " .read_ph=&" << pset->read_probe->name << ",";
-	}
-      else
-        {
-	  s.op->line() << " .read_pp=NULL,";
-	  s.op->line() << " .read_ph=NULL,";
-	}
-
-      if (pset->write_probe != NULL)
-        {
-	  s.op->line() << " .write_pp="
-		       << lex_cast_qstring (*pset->write_probe->sole_location())
-		       << ",";
-	  s.op->line() << " .write_ph=&" << pset->write_probe->name;
-	}
-      else
-        {
-	  s.op->line() << " .write_pp=NULL,";
-	  s.op->line() << " .write_ph=NULL";
-	}
-      s.op->line() << " },";
-  }
-  s.op->newline(-1) << "};";
-
-  if (has_read_probes)
-    {
-      // Output routine to fill in 'page' with our data.
-      s.op->newline();
-
-      s.op->newline() << "static int _stp_procfs_read(char *page, char **start, off_t off, int count, int *eof, void *data) {";
-
-      s.op->newline(1) << "struct stap_procfs_probe *spp = (struct stap_procfs_probe *)data;";
-      s.op->newline() << "int bytes = 0;";
-      s.op->newline() << "string_t strdata = {'\\0'};";
-
-      common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING", "spp->read_pp");
-
-      s.op->newline() << "if (c->data == NULL)";
-      s.op->newline(1) << "c->data = &strdata;";
-      s.op->newline(-1) << "else {";
-
-      s.op->newline(1) << "if (unlikely (atomic_inc_return (& skipped_count) > MAXSKIPPED)) {";
-      s.op->newline(1) << "atomic_set (& session_state, STAP_SESSION_ERROR);";
-      s.op->newline() << "_stp_exit ();";
-      s.op->newline(-1) << "}";
-      s.op->newline() << "atomic_dec (& c->busy);";
-      s.op->newline() << "goto probe_epilogue;";
-      s.op->newline(-1) << "}";
-
-      // call probe function (which copies data into strdata)
-      s.op->newline() << "(*spp->read_ph) (c);";
-
-      // copy string data into 'page'
-      s.op->newline() << "c->data = NULL;";
-      s.op->newline() << "bytes = strnlen(strdata, MAXSTRINGLEN - 1);";
-      s.op->newline() << "if (off >= bytes)";
-      s.op->newline(1) << "*eof = 1;";
-      s.op->newline(-1) << "else {";
-      s.op->newline(1) << "bytes -= off;";
-      s.op->newline() << "if (bytes > count)";
-      s.op->newline(1) << "bytes = count;";
-      s.op->newline(-1) << "memcpy(page, strdata + off, bytes);";
-      s.op->newline() << "*start = page;";
-      s.op->newline(-1) << "}";
-
-      common_probe_entryfn_epilogue (s.op);
-      s.op->newline() << "return bytes;";
-
-      s.op->newline(-1) << "}";
-    }
-  if (has_write_probes)
-    {
-      s.op->newline() << "static int _stp_procfs_write(struct file *file, const char *buffer, unsigned long count, void *data) {";
-
-      s.op->newline(1) << "struct stap_procfs_probe *spp = (struct stap_procfs_probe *)data;";
-      s.op->newline() << "string_t strdata = {'\\0'};";
-
-      common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING", "spp->write_pp");
-
-      s.op->newline() << "if (count > (MAXSTRINGLEN - 1))";
-      s.op->newline(1) << "count = MAXSTRINGLEN - 1;";
-      s.op->newline(-1) << "_stp_copy_from_user(strdata, buffer, count);";
-
-      s.op->newline() << "if (c->data == NULL)";
-      s.op->newline(1) << "c->data = &strdata;";
-      s.op->newline(-1) << "else {";
-
-      s.op->newline(1) << "if (unlikely (atomic_inc_return (& skipped_count) > MAXSKIPPED)) {";
-      s.op->newline(1) << "atomic_set (& session_state, STAP_SESSION_ERROR);";
-      s.op->newline() << "_stp_exit ();";
-      s.op->newline(-1) << "}";
-      s.op->newline() << "atomic_dec (& c->busy);";
-      s.op->newline() << "goto probe_epilogue;";
-      s.op->newline(-1) << "}";
-
-      // call probe function (which copies data out of strdata)
-      s.op->newline() << "(*spp->write_ph) (c);";
-
-      s.op->newline() << "c->data = NULL;";
-      common_probe_entryfn_epilogue (s.op);
-
-      s.op->newline() << "return count;";
-      s.op->newline(-1) << "}";
-    }
-}
-
-
-void
-procfs_derived_probe_group::emit_module_init (systemtap_session& s)
-{
-  if (probes_by_path.empty())
-    return;
-
-  s.op->newline() << "for (i = 0; i < " << probes_by_path.size() << "; i++) {";
-  s.op->newline(1) << "struct stap_procfs_probe *spp = &stap_procfs_probes[i];";
-
-  s.op->newline() << "if (spp->read_pp)";
-  s.op->newline(1) << "probe_point = spp->read_pp;";
-  s.op->newline(-1) << "else";
-  s.op->newline(1) << "probe_point = spp->write_pp;";
-
-  s.op->newline(-1) << "rc = _stp_create_procfs(spp->path, i);";
-
-  s.op->newline() << "if (rc) {";
-  s.op->newline(1) << "_stp_close_procfs();";
-  s.op->newline() << "break;";
-  s.op->newline(-1) << "}";
-
-  if (has_read_probes)
-    {
-      s.op->newline() << "if (spp->read_pp)";
-      s.op->newline(1) << "_stp_procfs_files[i]->read_proc = &_stp_procfs_read;";
-      s.op->newline(-1) << "else";
-      s.op->newline(1) << "_stp_procfs_files[i]->read_proc = NULL;";
-      s.op->indent(-1);
-    }
-  else
-    s.op->newline() << "_stp_procfs_files[i]->read_proc = NULL;";
-
-  if (has_write_probes)
-    {
-      s.op->newline() << "if (spp->write_pp)";
-      s.op->newline(1) << "_stp_procfs_files[i]->write_proc = &_stp_procfs_write;";
-      s.op->newline(-1) << "else";
-      s.op->newline(1) << "_stp_procfs_files[i]->write_proc = NULL;";
-      s.op->indent(-1);
-    }
-  else
-    s.op->newline() << "_stp_procfs_files[i]->write_proc = NULL;";
-
-  s.op->newline() << "_stp_procfs_files[i]->data = spp;";
-  s.op->newline(-1) << "}"; // for loop
-}
-
-
-void
-procfs_derived_probe_group::emit_module_exit (systemtap_session& s)
-{
-  if (probes_by_path.empty())
-    return;
-
-  s.op->newline() << "_stp_close_procfs();";
-}
-
-
-void
-procfs_var_expanding_visitor::visit_target_symbol (target_symbol* e)
-{
-  assert(e->base_name.size() > 0 && e->base_name[0] == '$');
-
-  if (e->base_name != "$value")
-    throw semantic_error ("invalid target symbol for procfs probe, $value expected",
-			  e->tok);
-
-  if (e->components.size() > 0)
-    {
-      switch (e->components[0].first)
-	{
-	case target_symbol::comp_literal_array_index:
-	  throw semantic_error("procfs target variable '$value' may not be used as array",
-			       e->tok);
-	  break;
-	case target_symbol::comp_struct_member:
-	  throw semantic_error("procfs target variable '$value' may not be used as a structure",
-			       e->tok);
-	  break;
-	default:
-	  throw semantic_error ("invalid use of procfs target variable '$value'",
-				e->tok);
-	  break;
-	}
-    }
-
-  bool lvalue = is_active_lvalue(e);
-  if (write_probe && lvalue)
-    throw semantic_error("procfs $value variable is read-only in a procfs write probe", e->tok);
-  else if (! write_probe && ! lvalue)
-    throw semantic_error("procfs $value variable cannot be read in a procfs read probe", e->tok);
-
-  // Remember that we've seen a target variable.
-  target_symbol_seen = true;
-
-  // Synthesize a function.
-  functiondecl *fdecl = new functiondecl;
-  fdecl->tok = e->tok;
-  embeddedcode *ec = new embeddedcode;
-  ec->tok = e->tok;
-
-  string fname = (string(lvalue ? "_procfs_value_set" : "_procfs_value_get")
-		  + "_" + lex_cast<string>(tick++));
-  string locvalue = "CONTEXT->data";
-
-  if (! lvalue)
-    ec->code = string("strlcpy (THIS->__retvalue, ") + locvalue
-      + string(", MAXSTRINGLEN); /* pure */");
-  else
-    ec->code = string("strlcpy (") + locvalue
-      + string(", THIS->value, MAXSTRINGLEN);");
-
-  fdecl->name = fname;
-  fdecl->body = ec;
-  fdecl->type = pe_string;
-
-  if (lvalue)
-    {
-      // Modify the fdecl so it carries a single pe_string formal
-      // argument called "value".
-
-      vardecl *v = new vardecl;
-      v->type = pe_string;
-      v->name = "value";
-      v->tok = e->tok;
-      fdecl->formal_args.push_back(v);
-    }
-  sess.functions[fdecl->name]=fdecl;
-
-  // Synthesize a functioncall.
-  functioncall* n = new functioncall;
-  n->tok = e->tok;
-  n->function = fname;
-  n->referent = 0; // NB: must not resolve yet, to ensure inclusion in session
-
-  if (lvalue)
-    {
-      // Provide the functioncall to our parent, so that it can be
-      // used to substitute for the assignment node immediately above
-      // us.
-      assert(!target_symbol_setter_functioncalls.empty());
-      *(target_symbol_setter_functioncalls.top()) = n;
-    }
-
-  provide (n);
-}
-
-
-struct procfs_builder: public derived_probe_builder
-{
-  procfs_builder() {}
-  virtual void build(systemtap_session & sess,
-		     probe * base,
-		     probe_point * location,
-		     literal_map_t const & parameters,
-		     vector<derived_probe *> & finished_results);
-};
-
-
-void
-procfs_builder::build(systemtap_session & sess,
-		      probe * base,
-		      probe_point * location,
-		      literal_map_t const & parameters,
-		      vector<derived_probe *> & finished_results)
-{
-  string path;
-  bool has_procfs = get_param(parameters, TOK_PROCFS, path);
-  bool has_read = (parameters.find(TOK_READ) != parameters.end());
-  bool has_write = (parameters.find(TOK_WRITE) != parameters.end());
-
-  // If no procfs path, default to "command".  The runtime will do
-  // this for us, but if we don't do it here, we'll think the
-  // following 2 probes are attached to different paths:
-  //
-  //   probe procfs("command").read {}"
-  //   probe procfs.write {}
-
-  if (! has_procfs)
-    path = "command";
-  // If we have a path, we need to validate it.
-  else
-    {
-      string::size_type start_pos, end_pos;
-      string component;
-      start_pos = 0;
-      while ((end_pos = path.find('/', start_pos)) != string::npos)
-        {
-	  // Make sure it doesn't start with '/'.
-	  if (end_pos == 0)
-	    throw semantic_error ("procfs path cannot start with a '/'",
-				  location->tok);
-
-	  component = path.substr(start_pos, end_pos - start_pos);
-	  // Make sure it isn't empty.
-	  if (component.size() == 0)
-	    throw semantic_error ("procfs path component cannot be empty",
-				  location->tok);
-	  // Make sure it isn't relative.
-	  else if (component == "." || component == "..")
-	    throw semantic_error ("procfs path cannot be relative (and contain '.' or '..')", location->tok);
-
-	  start_pos = end_pos + 1;
-	}
-      component = path.substr(start_pos);
-      // Make sure it doesn't end with '/'.
-      if (component.size() == 0)
-	throw semantic_error ("procfs path cannot end with a '/'", location->tok);
-      // Make sure it isn't relative.
-      else if (component == "." || component == "..")
-	throw semantic_error ("procfs path cannot be relative (and contain '.' or '..')", location->tok);
-    }
-
-  if (!(has_read ^ has_write))
-    throw semantic_error ("need read/write component", location->tok);
-
-  finished_results.push_back(new procfs_derived_probe(sess, base, location,
-						      path, has_write));
-}
-
-
-
-// ------------------------------------------------------------------------
 // statically inserted macro-based derived probes
 // ------------------------------------------------------------------------
 
@@ -10987,6 +10496,7 @@ void
 register_standard_tapsets(systemtap_session & s)
 {
   register_tapset_been(s);
+  register_tapset_procfs(s);
   register_tapset_timers(s);
 
   s.pattern_root->bind("perfmon")->bind_str("counter")
@@ -11061,14 +10571,6 @@ register_standard_tapsets(systemtap_session & s)
   s.pattern_root->bind(TOK_KERNEL)->bind_str(TOK_TRACE)
     ->bind(new tracepoint_builder());
 
-  // procfs parts
-  s.pattern_root->bind(TOK_PROCFS)->bind(TOK_READ)->bind(new procfs_builder());
-  s.pattern_root->bind_str(TOK_PROCFS)->bind(TOK_READ)
-    ->bind(new procfs_builder());
-  s.pattern_root->bind(TOK_PROCFS)->bind(TOK_WRITE)->bind(new procfs_builder());
-  s.pattern_root->bind_str(TOK_PROCFS)->bind(TOK_WRITE)
-    ->bind(new procfs_builder());
-
   // Kprobe based probe
   s.pattern_root->bind(TOK_KPROBE)->bind_str(TOK_FUNCTION)
      ->bind(new kprobe_builder());