Separate the permon tapset

1 files changed, 463 insertions, 0 deletions

diff --git a/tapset-perfmon.cxx b/tapset-perfmon.cxx
new file mode 100644
index 00000000..e3f30ece
--- /dev/null
+++ b/tapset-perfmon.cxx
@@ -0,0 +1,463 @@
+// tapset for HW performance monitoring
+// Copyright (C) 2005-2009 Red Hat Inc.
+// Copyright (C) 2005-2007 Intel Corporation.
+// Copyright (C) 2008 James.Bottomley@HansenPartnership.com
+//
+// This file is part of systemtap, and is free software.  You can
+// redistribute it and/or modify it under the terms of the GNU General
+// Public License (GPL); either version 2, or (at your option) any
+// later version.
+
+#include "session.h"
+#include "tapsets.h"
+#include "util.h"
+
+#include <string>
+
+#ifdef PERFMON
+#include <perfmon/pfmlib.h>
+#include <perfmon/perfmon.h>
+#endif
+
+
+using namespace std;
+using namespace __gnu_cxx;
+
+
+
+// ------------------------------------------------------------------------
+// perfmon derived probes
+// ------------------------------------------------------------------------
+// This is a new interface to the perfmon hw.
+//
+
+
+struct perfmon_var_expanding_visitor: public var_expanding_visitor
+{
+  systemtap_session & sess;
+  unsigned counter_number;
+  perfmon_var_expanding_visitor(systemtap_session & s, unsigned c):
+    sess(s), counter_number(c) {}
+  void visit_target_symbol (target_symbol* e);
+};
+
+
+void
+perfmon_var_expanding_visitor::visit_target_symbol (target_symbol *e)
+{
+  assert(e->base_name.size() > 0 && e->base_name[0] == '$');
+
+  // Synthesize a function.
+  functiondecl *fdecl = new functiondecl;
+  fdecl->tok = e->tok;
+  embeddedcode *ec = new embeddedcode;
+  ec->tok = e->tok;
+  bool lvalue = is_active_lvalue(e);
+
+  if (lvalue )
+    throw semantic_error("writes to $counter not permitted");
+
+  string fname = string("_perfmon_tvar_get")
+                  + "_" + e->base_name.substr(1)
+                  + "_" + lex_cast<string>(counter_number);
+
+  if (e->base_name != "$counter")
+    throw semantic_error ("target variables not available to perfmon probes");
+
+  if (e->components.size() > 0)
+    {
+      switch (e->components[0].first)
+        {
+        case target_symbol::comp_literal_array_index:
+          throw semantic_error("perfmon probe '$counter' variable may not be used as array",
+                               e->tok);
+          break;
+        case target_symbol::comp_struct_member:
+          throw semantic_error("perfmon probe '$counter' variable may not be used as a structure",
+                               e->tok);
+          break;
+        default:
+          throw semantic_error ("invalid use of perfmon probe '$counter' variable",
+                                e->tok);
+          break;
+        }
+    }
+
+  ec->code = "THIS->__retvalue = _pfm_pmd_x[" +
+          lex_cast<string>(counter_number) + "].reg_num;";
+  ec->code += "/* pure */";
+  fdecl->name = fname;
+  fdecl->body = ec;
+  fdecl->type = pe_long;
+  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
+
+  provide (n);
+}
+
+
+enum perfmon_mode
+{
+  perfmon_count,
+  perfmon_sample
+};
+
+
+struct perfmon_derived_probe: public derived_probe
+{
+protected:
+  static unsigned probes_allocated;
+
+public:
+  systemtap_session & sess;
+  string event;
+  perfmon_mode mode;
+
+  perfmon_derived_probe (probe* p, probe_point* l, systemtap_session &s,
+                         string e, perfmon_mode m);
+  virtual void join_group (systemtap_session& s);
+};
+
+
+struct perfmon_derived_probe_group: public generic_dpg<perfmon_derived_probe>
+{
+public:
+  void emit_module_decls (systemtap_session&) {}
+  void emit_module_init (systemtap_session&) {}
+  void emit_module_exit (systemtap_session&) {}
+};
+
+
+struct perfmon_builder: public derived_probe_builder
+{
+  perfmon_builder() {}
+  virtual void build(systemtap_session & sess,
+                     probe * base,
+                     probe_point * location,
+                     literal_map_t const & parameters,
+                     vector<derived_probe *> & finished_results)
+  {
+    string event;
+    if (!get_param (parameters, "counter", event))
+      throw semantic_error("perfmon requires an event");
+
+    sess.perfmon++;
+
+    // XXX: need to revise when doing sampling
+    finished_results.push_back(new perfmon_derived_probe(base, location,
+                                                         sess, event,
+                                                         perfmon_count));
+  }
+};
+
+
+unsigned perfmon_derived_probe::probes_allocated;
+
+perfmon_derived_probe::perfmon_derived_probe (probe* p, probe_point* l,
+                                              systemtap_session &s,
+                                              string e, perfmon_mode m)
+        : derived_probe (p, l), sess(s), event(e), mode(m)
+{
+  ++probes_allocated;
+
+  // Now expand the local variables in the probe body
+  perfmon_var_expanding_visitor v (sess, probes_allocated-1);
+  this->body = v.require (this->body);
+
+  if (sess.verbose > 1)
+    clog << "perfmon-based probe" << endl;
+}
+
+
+void
+perfmon_derived_probe::join_group (systemtap_session& s)
+{
+  throw semantic_error ("incomplete", this->tok);
+
+  if (! s.perfmon_derived_probes)
+    s.perfmon_derived_probes = new perfmon_derived_probe_group ();
+  s.perfmon_derived_probes->enroll (this);
+}
+
+
+#if 0
+void
+perfmon_derived_probe::emit_registrations_start (translator_output* o,
+                                                 unsigned index)
+{
+  for (unsigned i=0; i<locations.size(); i++)
+    o->newline() << "enter_" << name << "_" << i << " ();";
+}
+
+
+void
+perfmon_derived_probe::emit_registrations_end (translator_output * o,
+                                               unsigned index)
+{
+}
+
+
+void
+perfmon_derived_probe::emit_deregistrations (translator_output * o)
+{
+}
+
+
+void
+perfmon_derived_probe::emit_probe_entries (translator_output * o)
+{
+  o->newline() << "#ifdef STP_TIMING";
+  // NB: This variable may be multiply (but identically) defined.
+  o->newline() << "static __cacheline_aligned Stat " << "time_" << basest()->name << ";";
+  o->newline() << "#endif";
+
+  for (unsigned i=0; i<locations.size(); i++)
+    {
+      probe_point *l = locations[i];
+      o->newline() << "/* location " << i << ": " << *l << " */";
+      o->newline() << "static void enter_" << name << "_" << i << " (void) {";
+
+      o->indent(1);
+      o->newline() << "const char* probe_point = "
+                   << lex_cast_qstring(*l) << ";";
+
+      o->newline() << "static struct pfarg_ctx _pfm_context;";
+      o->newline() << "static void *_pfm_desc;";
+      o->newline() << "static struct pfarg_pmc *_pfm_pmc_x;";
+      o->newline() << "static int _pfm_num_pmc_x;";
+      o->newline() << "static struct pfarg_pmd *_pfm_pmd_x;";
+      o->newline() << "static int _pfm_num_pmd_x;";
+
+      emit_probe_prologue (o,
+                           (mode == perfmon_count ?
+                            "STAP_SESSION_STARTING" :
+                            "STAP_SESSION_RUNNING"),
+                           "probe_point");
+
+      // NB: locals are initialized by probe function itself
+      o->newline() << name << " (c);";
+
+      emit_probe_epilogue (o);
+
+      o->newline(-1) << "}\n";
+    }
+}
+#endif
+
+
+#if 0
+void no_pfm_event_error (string s)
+{
+  string msg(string("Cannot find event:" + s));
+  throw semantic_error(msg);
+}
+
+
+void no_pfm_mask_error (string s)
+{
+  string msg(string("Cannot find mask:" + s));
+  throw semantic_error(msg);
+}
+
+
+void
+split(const string& s, vector<string>& v, const string & separator)
+{
+  string::size_type last_pos = s.find_first_not_of(separator, 0);
+  string::size_type pos = s.find_first_of(separator, last_pos);
+
+  while (string::npos != pos || string::npos != last_pos) {
+    v.push_back(s.substr(last_pos, pos - last_pos));
+    last_pos = s.find_first_not_of(separator, pos);
+    pos = s.find_first_of(separator, last_pos);
+  }
+}
+
+
+void
+perfmon_derived_probe_group::emit_probes (translator_output* op, unparser* up)
+{
+  for (unsigned i=0; i < probes.size(); i++)
+    {
+      op->newline ();
+      up->emit_probe (probes[i]);
+    }
+}
+
+
+void
+perfmon_derived_probe_group::emit_module_init (translator_output* o)
+{
+  int ret;
+  pfmlib_input_param_t inp;
+  pfmlib_output_param_t outp;
+  pfarg_pmd_t pd[PFMLIB_MAX_PMDS];
+  pfarg_pmc_t pc[PFMLIB_MAX_PMCS];
+  pfarg_ctx_t ctx;
+  pfarg_load_t load_args;
+  pfmlib_options_t pfmlib_options;
+  unsigned int max_counters;
+
+  if ( probes.size() == 0)
+          return;
+  ret = pfm_initialize();
+  if (ret != PFMLIB_SUCCESS)
+    throw semantic_error("Unable to generate performance monitoring events (no libpfm)");
+
+  pfm_get_num_counters(&max_counters);
+
+  memset(&pfmlib_options, 0, sizeof(pfmlib_options));
+  pfmlib_options.pfm_debug   = 0; /* set to 1 for debug */
+  pfmlib_options.pfm_verbose = 0; /* set to 1 for debug */
+  pfm_set_options(&pfmlib_options);
+
+  memset(pd, 0, sizeof(pd));
+  memset(pc, 0, sizeof(pc));
+  memset(&ctx, 0, sizeof(ctx));
+  memset(&load_args, 0, sizeof(load_args));
+
+  /*
+   * prepare parameters to library.
+   */
+  memset(&inp,0, sizeof(inp));
+  memset(&outp,0, sizeof(outp));
+
+  /* figure out the events */
+  for (unsigned i=0; i<probes.size(); ++i)
+    {
+      if (probes[i]->event == "cycles") {
+        if (pfm_get_cycle_event( &inp.pfp_events[i].event) != PFMLIB_SUCCESS)
+          no_pfm_event_error(probes[i]->event);
+      } else if (probes[i]->event == "instructions") {
+        if (pfm_get_inst_retired_event( &inp.pfp_events[i].event) !=
+            PFMLIB_SUCCESS)
+          no_pfm_event_error(probes[i]->event);
+      } else {
+        unsigned int event_id = 0;
+        unsigned int mask_id = 0;
+        vector<string> event_spec;
+        split(probes[i]->event, event_spec, ":");
+        int num =  event_spec.size();
+        int masks = num - 1;
+
+        if (num == 0)
+          throw semantic_error("No events found");
+
+        /* setup event */
+        if (pfm_find_event(event_spec[0].c_str(), &event_id) != PFMLIB_SUCCESS)
+          no_pfm_event_error(event_spec[0]);
+        inp.pfp_events[i].event = event_id;
+
+        /* set up masks */
+        if (masks > PFMLIB_MAX_MASKS_PER_EVENT)
+          throw semantic_error("Too many unit masks specified");
+
+        for (int j=0; j < masks; j++) {
+                if (pfm_find_event_mask(event_id, event_spec[j+1].c_str(),
+                                        &mask_id) != PFMLIB_SUCCESS)
+            no_pfm_mask_error(string(event_spec[j+1]));
+          inp.pfp_events[i].unit_masks[j] = mask_id;
+        }
+        inp.pfp_events[i].num_masks = masks;
+      }
+    }
+
+  /* number of counters in use */
+  inp.pfp_event_count = probes.size();
+
+  // XXX: no elimination of duplicated counters
+  if (inp.pfp_event_count>max_counters)
+          throw semantic_error("Too many performance monitoring events.");
+
+  /* count events both in kernel and user-space */
+  inp.pfp_dfl_plm   = PFM_PLM0 | PFM_PLM3;
+
+  /* XXX: some cases a perfmon register might be used of watch dog
+     this code doesn't handle that case */
+
+  /* figure out the pmcs for the events */
+  if ((ret=pfm_dispatch_events(&inp, NULL, &outp, NULL)) != PFMLIB_SUCCESS)
+          throw semantic_error("Cannot configure events");
+
+  for (unsigned i=0; i < outp.pfp_pmc_count; i++) {
+    pc[i].reg_num   = outp.pfp_pmcs[i].reg_num;
+    pc[i].reg_value = outp.pfp_pmcs[i].reg_value;
+  }
+
+  /*
+   * There could be more pmc settings than pmd.
+   * Figure out the actual pmds to use.
+   */
+  for (unsigned i=0, j=0; i < inp.pfp_event_count; i++) {
+    pd[i].reg_num   = outp.pfp_pmcs[j].reg_pmd_num;
+    for(; j < outp.pfp_pmc_count; j++)
+      if (outp.pfp_pmcs[j].reg_evt_idx != i) break;
+  }
+
+  // Output the be probes create function
+  o->newline() << "static int register_perfmon_probes (void) {";
+  o->newline(1) << "int rc = 0;";
+
+  o->newline() << "/* data for perfmon */";
+  o->newline() << "static int _pfm_num_pmc = " << outp.pfp_pmc_count << ";";
+  o->newline() << "static struct pfarg_pmc _pfm_pmc[" << outp.pfp_pmc_count
+               << "] = {";
+  /* output the needed bits for pmc here */
+  for (unsigned i=0; i < outp.pfp_pmc_count; i++) {
+    o->newline() << "{.reg_num=" << pc[i].reg_num << ", "
+                 << ".reg_value=" << lex_cast_hex<string>(pc[i].reg_value)
+                 << "},";
+  }
+
+  o->newline() << "};";
+  o->newline() << "static int _pfm_num_pmd = " << inp.pfp_event_count << ";";
+  o->newline() << "static struct pfarg_pmd _pfm_pmd[" << inp.pfp_event_count
+               << "] = {";
+  /* output the needed bits for pmd here */
+  for (unsigned i=0; i < inp.pfp_event_count; i++) {
+    o->newline() << "{.reg_num=" << pd[i].reg_num << ", "
+                 << ".reg_value=" << pd[i].reg_value << "},";
+  }
+  o->newline() << "};";
+  o->newline();
+
+  o->newline() << "_pfm_pmc_x=_pfm_pmc;";
+  o->newline() << "_pfm_num_pmc_x=_pfm_num_pmc;";
+  o->newline() << "_pfm_pmd_x=_pfm_pmd;";
+  o->newline() << "_pfm_num_pmd_x=_pfm_num_pmd;";
+
+  // call all the function bodies associated with perfcounters
+  for (unsigned i=0; i < probes.size (); i++)
+    probes[i]->emit_registrations_start (o,i);
+
+  /* generate call to turn on instrumentation */
+  o->newline() << "_pfm_context.ctx_flags |= PFM_FL_SYSTEM_WIDE;";
+  o->newline() << "rc = rc || _stp_perfmon_setup(&_pfm_desc, &_pfm_context,";
+  o->newline(1) << "_pfm_pmc, _pfm_num_pmc,";
+  o->newline() << "_pfm_pmd, _pfm_num_pmd);";
+  o->newline(-1);
+
+  o->newline() << "return rc;";
+  o->newline(-1) << "}\n";
+
+  // Output the be probes destroy function
+  o->newline() << "static void unregister_perfmon_probes (void) {";
+  o->newline(1) << "_stp_perfmon_shutdown(_pfm_desc);";
+  o->newline(-1) << "}\n";
+}
+#endif
+
+
+void
+register_tapset_perfmon(systemtap_session& s)
+{
+  s.pattern_root->bind("perfmon")->bind_str("counter")
+    ->bind(new perfmon_builder());
+}
+
+/* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */