[systemtap.git] / tapset-itrace.cxx

// tapset for timers
// Copyright (C) 2005-2013 Red Hat Inc.
// Copyright (C) 2005-2007 Intel Corporation.
//
// 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 "task_finder.h"
#include "translate.h"
#include "util.h"

#include <cstring>
#include <string>


using namespace std;
using namespace __gnu_cxx;


static const string TOK_PROCESS("process");
static const string TOK_INSN("insn");
static const string TOK_BLOCK("block");


// ------------------------------------------------------------------------
// itrace user-space probes
// ------------------------------------------------------------------------


struct itrace_derived_probe: public derived_probe
{
  bool has_path;
  string path;
  int64_t pid;
  int single_step;

  itrace_derived_probe (systemtap_session &s, probe* p, probe_point* l,
                        bool hp, string &pn, int64_t pd, int ss
			);
  void join_group (systemtap_session& s);
};


struct itrace_derived_probe_group: public generic_dpg<itrace_derived_probe>
{
private:
  map<string, vector<itrace_derived_probe*> > probes_by_path;
  typedef map<string, vector<itrace_derived_probe*> >::iterator p_b_path_iterator;
  map<int64_t, vector<itrace_derived_probe*> > probes_by_pid;
  typedef map<int64_t, vector<itrace_derived_probe*> >::iterator p_b_pid_iterator;
  unsigned num_probes;

  void emit_probe_decl (systemtap_session& s, itrace_derived_probe *p);

public:
  itrace_derived_probe_group(): num_probes(0) { }

  void enroll (itrace_derived_probe* probe);
  void emit_module_decls (systemtap_session& s);
  void emit_module_init (systemtap_session& s);
  void emit_module_exit (systemtap_session& s);
};


itrace_derived_probe::itrace_derived_probe (systemtap_session &s,
                                            probe* p, probe_point* l,
                                            bool hp, string &pn, int64_t pd,
					    int ss
					    ):
  derived_probe(p, l), has_path(hp), path(pn), pid(pd), single_step(ss)
{
  if (s.kernel_config["CONFIG_UTRACE"] != string("y"))
    throw semantic_error (_("process probes not available without kernel CONFIG_UTRACE"));
}


void
itrace_derived_probe::join_group (systemtap_session& s)
{
  if (! s.itrace_derived_probes)
    s.itrace_derived_probes = new itrace_derived_probe_group ();

  s.itrace_derived_probes->enroll (this);

  enable_task_finder(s);
}

struct itrace_builder: public derived_probe_builder
{
  itrace_builder() {}
  virtual void build(systemtap_session & sess,
		     probe * base,
		     probe_point * location,
		     std::map<std::string, literal *> const & parameters,
		     vector<derived_probe *> & finished_results)
  {
    string path, path_tgt;
    int64_t pid = 0;
    int single_step;

    bool has_path = get_param (parameters, TOK_PROCESS, path);
    bool has_pid = get_param (parameters, TOK_PROCESS, pid);
    // XXX: PR 6445 needs !has_path && !has_pid support
    assert (has_path || has_pid);

    single_step = ! has_null_param (parameters, TOK_BLOCK);

    // If we have a path, we need to validate it.
    if (has_path)
      {
        path = find_executable (path, sess.sysroot, sess.sysenv);
        sess.unwindsym_modules.insert (path);
        path_tgt = path_remove_sysroot(sess, path);
      }

    finished_results.push_back(new itrace_derived_probe(sess, base, location,
							has_path, path_tgt, pid,
							single_step
							));
  }
};


void
itrace_derived_probe_group::enroll (itrace_derived_probe* p)
{
  if (p->has_path)
    probes_by_path[p->path].push_back(p);
  else
    probes_by_pid[p->pid].push_back(p);
  num_probes++;

  // XXX: multiple exec probes (for instance) for the same path (or
  // pid) should all share a itrace report function, and have their
  // handlers executed sequentially.
}


void
itrace_derived_probe_group::emit_probe_decl (systemtap_session& s,
					     itrace_derived_probe *p)
{
  s.op->newline() << "{";
  s.op->line() << " .tgt={";
  s.op->line() << " .purpose=\"itrace\",";

  if (p->has_path)
    {
      s.op->line() << " .procname=\"" << p->path << "\",";
      s.op->line() << " .pid=0,";
    }
  else
    {
      s.op->line() << " .procname=NULL,";
      s.op->line() << " .pid=" << p->pid << ",";
    }

  s.op->line() << " .callback=&_stp_itrace_probe_cb,";
  s.op->line() << " },";
  s.op->line() << " .probe=" << common_probe_init (p) << ",";
  s.op->line() << " .single_step=" << p->single_step << ",";
  s.op->line() << " },";
}


void
itrace_derived_probe_group::emit_module_decls (systemtap_session& s)
{
  if (probes_by_path.empty() && probes_by_pid.empty())
    return;

  s.op->newline();
  s.op->newline() << "/* ---- itrace probes ---- */";

  s.op->newline() << "struct stap_itrace_probe {";
  s.op->indent(1);
  s.op->newline() << "struct stap_task_finder_target tgt;";
  s.op->newline() << "const struct stap_probe * const probe;";
  s.op->newline() << "int single_step;";
  s.op->newline(-1) << "};";
  s.op->newline() << "static void enter_itrace_probe(struct stap_itrace_probe *p, struct pt_regs *regs, void *data);";
  s.op->newline() << "#include \"linux/itrace.c\"";

  // output routine to call itrace probe
  s.op->newline() << "static void enter_itrace_probe(struct stap_itrace_probe *p, struct pt_regs *regs, void *data) {";
  s.op->indent(1);

  common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "p->probe",
				 "stp_probe_type_itrace");
  s.op->newline() << "c->uregs = regs;";
  s.op->newline() << "c->user_mode_p = 1;";

  // call probe function
  s.op->newline() << "(*p->probe->ph) (c);";
  common_probe_entryfn_epilogue (s, true);

  s.op->newline() << "return;";
  s.op->newline(-1) << "}";

  // Output task finder callback routine that gets called for all
  // itrace probe types.
  s.op->newline() << "static int _stp_itrace_probe_cb(struct stap_task_finder_target *tgt, struct task_struct *tsk, int register_p, int process_p) {";
  s.op->indent(1);
  s.op->newline() << "int rc = 0;";
  s.op->newline() << "struct stap_itrace_probe *p = container_of(tgt, struct stap_itrace_probe, tgt);";

  s.op->newline() << "if (register_p) ";
  s.op->indent(1);

  s.op->newline() << "rc = usr_itrace_init(p->single_step, tsk, p);";
  s.op->newline(-1) << "else";
  s.op->newline(1) << "remove_usr_itrace_info(find_itrace_info(tsk));";
  s.op->newline(-1) << "return rc;";
  s.op->newline(-1) << "}";

  s.op->newline() << "static struct stap_itrace_probe stap_itrace_probes[] = {";
  s.op->indent(1);

  // Set up 'process(PATH)' probes
  if (! probes_by_path.empty())
    {
      for (p_b_path_iterator it = probes_by_path.begin();
	   it != probes_by_path.end(); it++)
        {
	  for (unsigned i = 0; i < it->second.size(); i++)
	    {
	      itrace_derived_probe *p = it->second[i];
	      emit_probe_decl(s, p);
	    }
	}
    }

  // Set up 'process(PID)' probes
  if (! probes_by_pid.empty())
    {
      for (p_b_pid_iterator it = probes_by_pid.begin();
	   it != probes_by_pid.end(); it++)
        {
	  for (unsigned i = 0; i < it->second.size(); i++)
	    {
	      itrace_derived_probe *p = it->second[i];
	      emit_probe_decl(s, p);
	    }
	}
    }
  s.op->newline(-1) << "};";
}


void
itrace_derived_probe_group::emit_module_init (systemtap_session& s)
{
  if (probes_by_path.empty() && probes_by_pid.empty())
    return;

  s.op->newline();
  s.op->newline() << "/* ---- itrace probes ---- */";

  s.op->newline() << "for (i=0; i<" << num_probes << "; i++) {";
  s.op->indent(1);
  s.op->newline() << "struct stap_itrace_probe *p = &stap_itrace_probes[i];";

  // 'arch_has_single_step' needs to be defined for either single step mode
  // or branch mode.
  s.op->newline() << "if (!arch_has_single_step()) {";
  s.op->indent(1);
  s.op->newline() << "_stp_error (\"insn probe init: arch does not support step mode\");";
  s.op->newline() << "rc = -EPERM;";
  s.op->newline() << "break;";
  s.op->newline(-1) << "}";
  s.op->newline() << "if (!p->single_step && !arch_has_block_step()) {";
  s.op->indent(1);
  s.op->newline() << "_stp_error (\"insn probe init: arch does not support block step mode\");";
  s.op->newline() << "rc = -EPERM;";
  s.op->newline() << "break;";
  s.op->newline(-1) << "}";

  s.op->newline() << "rc = stap_register_task_finder_target(&p->tgt);";
  s.op->newline(-1) << "}";
}


void
itrace_derived_probe_group::emit_module_exit (systemtap_session& s)
{
  if (probes_by_path.empty() && probes_by_pid.empty()) return;
  s.op->newline();
  s.op->newline() << "/* ---- itrace probes ---- */";
  s.op->newline() << "cleanup_usr_itrace();";
}

void
register_tapset_itrace(systemtap_session& s)
{
  match_node* root = s.pattern_root;
  derived_probe_builder *builder = new itrace_builder();

  root->bind_str(TOK_PROCESS)->bind(TOK_INSN)
    ->bind(builder);
  root->bind_num(TOK_PROCESS)->bind(TOK_INSN)
    ->bind(builder);
  root->bind_str(TOK_PROCESS)->bind(TOK_INSN)->bind(TOK_BLOCK)
    ->bind(builder);
  root->bind_num(TOK_PROCESS)->bind(TOK_INSN)->bind(TOK_BLOCK)
    ->bind(builder);
}


/* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */
Commit	Line	Data
93646f4d	1	// tapset for timers
1af100fc	2	// Copyright (C) 2005-2013 Red Hat Inc.
93646f4d	3	// Copyright (C) 2005-2007 Intel Corporation.
93646f4d JS	4	//
	5	// This file is part of systemtap, and is free software. You can
	6	// redistribute it and/or modify it under the terms of the GNU General
	7	// Public License (GPL); either version 2, or (at your option) any
	8	// later version.
	9
	10
	11	#include "session.h"
	12	#include "tapsets.h"
	13	#include "task_finder.h"
	14	#include "translate.h"
	15	#include "util.h"
	16
	17	#include <cstring>
	18	#include <string>
	19
	20
	21	using namespace std;
	22	using namespace __gnu_cxx;
	23
	24
4627ed58 JS	25	static const string TOK_PROCESS("process");
	26	static const string TOK_INSN("insn");
	27	static const string TOK_BLOCK("block");
93646f4d JS	28
	29
	30	// ------------------------------------------------------------------------
	31	// itrace user-space probes
	32	// ------------------------------------------------------------------------
	33
	34
	35	struct itrace_derived_probe: public derived_probe
	36	{
	37	bool has_path;
	38	string path;
	39	int64_t pid;
	40	int single_step;
	41
	42	itrace_derived_probe (systemtap_session &s, probe* p, probe_point* l,
	43	bool hp, string &pn, int64_t pd, int ss
	44	);
	45	void join_group (systemtap_session& s);
	46	};
	47
	48
	49	struct itrace_derived_probe_group: public generic_dpg<itrace_derived_probe>
	50	{
	51	private:
	52	map<string, vector<itrace_derived_probe*> > probes_by_path;
	53	typedef map<string, vector<itrace_derived_probe*> >::iterator p_b_path_iterator;
	54	map<int64_t, vector<itrace_derived_probe*> > probes_by_pid;
	55	typedef map<int64_t, vector<itrace_derived_probe*> >::iterator p_b_pid_iterator;
	56	unsigned num_probes;
	57
	58	void emit_probe_decl (systemtap_session& s, itrace_derived_probe *p);
	59
	60	public:
	61	itrace_derived_probe_group(): num_probes(0) { }
	62
	63	void enroll (itrace_derived_probe* probe);
	64	void emit_module_decls (systemtap_session& s);
	65	void emit_module_init (systemtap_session& s);
	66	void emit_module_exit (systemtap_session& s);
	67	};
	68
	69
	70	itrace_derived_probe::itrace_derived_probe (systemtap_session &s,
	71	probe* p, probe_point* l,
	72	bool hp, string &pn, int64_t pd,
	73	int ss
	74	):
	75	derived_probe(p, l), has_path(hp), path(pn), pid(pd), single_step(ss)
	76	{
e34d5d13	77	if (s.kernel_config["CONFIG_UTRACE"] != string("y"))
efee9a98	78	throw semantic_error (_("process probes not available without kernel CONFIG_UTRACE"));
93646f4d JS	79	}
	80
	81
	82	void
	83	itrace_derived_probe::join_group (systemtap_session& s)
	84	{
	85	if (! s.itrace_derived_probes)
	86	s.itrace_derived_probes = new itrace_derived_probe_group ();
	87
	88	s.itrace_derived_probes->enroll (this);
	89
	90	enable_task_finder(s);
	91	}
	92
	93	struct itrace_builder: public derived_probe_builder
	94	{
	95	itrace_builder() {}
	96	virtual void build(systemtap_session & sess,
	97	probe * base,
	98	probe_point * location,
	99	std::map<std::string, literal *> const & parameters,
	100	vector<derived_probe *> & finished_results)
	101	{
05fb3e0c	102	string path, path_tgt;
93646f4d JS	103	int64_t pid = 0;
	104	int single_step;
	105
	106	bool has_path = get_param (parameters, TOK_PROCESS, path);
	107	bool has_pid = get_param (parameters, TOK_PROCESS, pid);
	108	// XXX: PR 6445 needs !has_path && !has_pid support
	109	assert (has_path \|\| has_pid);
	110
	111	single_step = ! has_null_param (parameters, TOK_BLOCK);
	112
	113	// If we have a path, we need to validate it.
	114	if (has_path)
671ceda8	115	{
05fb3e0c	116	path = find_executable (path, sess.sysroot, sess.sysenv);
671ceda8	117	sess.unwindsym_modules.insert (path);
05fb3e0c	118	path_tgt = path_remove_sysroot(sess, path);
671ceda8	119	}
93646f4d JS	120
93646f4d JS	121	finished_results.push_back(new itrace_derived_probe(sess, base, location,
05fb3e0c	122	has_path, path_tgt, pid,
93646f4d JS	123	single_step
	124	));
	125	}
	126	};
	127
	128
	129	void
	130	itrace_derived_probe_group::enroll (itrace_derived_probe* p)
	131	{
	132	if (p->has_path)
	133	probes_by_path[p->path].push_back(p);
	134	else
	135	probes_by_pid[p->pid].push_back(p);
	136	num_probes++;
	137
	138	// XXX: multiple exec probes (for instance) for the same path (or
	139	// pid) should all share a itrace report function, and have their
	140	// handlers executed sequentially.
	141	}
	142
	143
	144	void
	145	itrace_derived_probe_group::emit_probe_decl (systemtap_session& s,
	146	itrace_derived_probe *p)
	147	{
	148	s.op->newline() << "{";
	149	s.op->line() << " .tgt={";
1af100fc	150	s.op->line() << " .purpose=\"itrace\",";
93646f4d JS	151
	152	if (p->has_path)
	153	{
b6921d59	154	s.op->line() << " .procname=\"" << p->path << "\",";
93646f4d JS	155	s.op->line() << " .pid=0,";
	156	}
	157	else
	158	{
b6921d59	159	s.op->line() << " .procname=NULL,";
93646f4d JS	160	s.op->line() << " .pid=" << p->pid << ",";
	161	}
	162
	163	s.op->line() << " .callback=&_stp_itrace_probe_cb,";
	164	s.op->line() << " },";
faea5e16	165	s.op->line() << " .probe=" << common_probe_init (p) << ",";
93646f4d	166	s.op->line() << " .single_step=" << p->single_step << ",";
93646f4d JS	167	s.op->line() << " },";
	168	}
	169
	170
	171	void
	172	itrace_derived_probe_group::emit_module_decls (systemtap_session& s)
	173	{
	174	if (probes_by_path.empty() && probes_by_pid.empty())
	175	return;
	176
	177	s.op->newline();
	178	s.op->newline() << "/* ---- itrace probes ---- */";
	179
	180	s.op->newline() << "struct stap_itrace_probe {";
	181	s.op->indent(1);
	182	s.op->newline() << "struct stap_task_finder_target tgt;";
7c3e97f4	183	s.op->newline() << "const struct stap_probe * const probe;";
93646f4d JS	184	s.op->newline() << "int single_step;";
	185	s.op->newline(-1) << "};";
	186	s.op->newline() << "static void enter_itrace_probe(struct stap_itrace_probe p, struct pt_regs regs, void *data);";
2ba1736a	187	s.op->newline() << "#include \"linux/itrace.c\"";
93646f4d JS	188
	189	// output routine to call itrace probe
	190	s.op->newline() << "static void enter_itrace_probe(struct stap_itrace_probe p, struct pt_regs regs, void *data) {";
	191	s.op->indent(1);
	192
71db462b	193	common_probe_entryfn_prologue (s, "STAP_SESSION_RUNNING", "p->probe",
cda141c2	194	"stp_probe_type_itrace");
d9aed31e	195	s.op->newline() << "c->uregs = regs;";
e04b5d74	196	s.op->newline() << "c->user_mode_p = 1;";
93646f4d JS	197
93646f4d JS	198	// call probe function
26e63673	199	s.op->newline() << "(*p->probe->ph) (c);";
f887a8c9	200	common_probe_entryfn_epilogue (s, true);
93646f4d JS	201
	202	s.op->newline() << "return;";
	203	s.op->newline(-1) << "}";
	204
	205	// Output task finder callback routine that gets called for all
	206	// itrace probe types.
	207	s.op->newline() << "static int _stp_itrace_probe_cb(struct stap_task_finder_target tgt, struct task_struct tsk, int register_p, int process_p) {";
	208	s.op->indent(1);
	209	s.op->newline() << "int rc = 0;";
	210	s.op->newline() << "struct stap_itrace_probe *p = container_of(tgt, struct stap_itrace_probe, tgt);";
	211
	212	s.op->newline() << "if (register_p) ";
	213	s.op->indent(1);
	214
c8a44dea	215	s.op->newline() << "rc = usr_itrace_init(p->single_step, tsk, p);";
93646f4d	216	s.op->newline(-1) << "else";
4f600a5f	217	s.op->newline(1) << "remove_usr_itrace_info(find_itrace_info(tsk));";
93646f4d JS	218	s.op->newline(-1) << "return rc;";
	219	s.op->newline(-1) << "}";
	220
93646f4d JS	221	s.op->newline() << "static struct stap_itrace_probe stap_itrace_probes[] = {";
	222	s.op->indent(1);
	223
	224	// Set up 'process(PATH)' probes
	225	if (! probes_by_path.empty())
	226	{
	227	for (p_b_path_iterator it = probes_by_path.begin();
	228	it != probes_by_path.end(); it++)
	229	{
	230	for (unsigned i = 0; i < it->second.size(); i++)
	231	{
	232	itrace_derived_probe *p = it->second[i];
	233	emit_probe_decl(s, p);
	234	}
	235	}
	236	}
	237
	238	// Set up 'process(PID)' probes
	239	if (! probes_by_pid.empty())
	240	{
	241	for (p_b_pid_iterator it = probes_by_pid.begin();
	242	it != probes_by_pid.end(); it++)
	243	{
	244	for (unsigned i = 0; i < it->second.size(); i++)
	245	{
	246	itrace_derived_probe *p = it->second[i];
	247	emit_probe_decl(s, p);
	248	}
	249	}
	250	}
	251	s.op->newline(-1) << "};";
	252	}
	253
	254
	255	void
	256	itrace_derived_probe_group::emit_module_init (systemtap_session& s)
	257	{
	258	if (probes_by_path.empty() && probes_by_pid.empty())
	259	return;
	260
93646f4d JS	261	s.op->newline();
	262	s.op->newline() << "/* ---- itrace probes ---- */";
	263
	264	s.op->newline() << "for (i=0; i<" << num_probes << "; i++) {";
	265	s.op->indent(1);
	266	s.op->newline() << "struct stap_itrace_probe *p = &stap_itrace_probes[i];";
	267
	268	// 'arch_has_single_step' needs to be defined for either single step mode
	269	// or branch mode.
	270	s.op->newline() << "if (!arch_has_single_step()) {";
	271	s.op->indent(1);
	272	s.op->newline() << "_stp_error (\"insn probe init: arch does not support step mode\");";
	273	s.op->newline() << "rc = -EPERM;";
	274	s.op->newline() << "break;";
	275	s.op->newline(-1) << "}";
	276	s.op->newline() << "if (!p->single_step && !arch_has_block_step()) {";
	277	s.op->indent(1);
	278	s.op->newline() << "_stp_error (\"insn probe init: arch does not support block step mode\");";
	279	s.op->newline() << "rc = -EPERM;";
	280	s.op->newline() << "break;";
	281	s.op->newline(-1) << "}";
	282
	283	s.op->newline() << "rc = stap_register_task_finder_target(&p->tgt);";
	284	s.op->newline(-1) << "}";
	285	}
	286
	287
	288	void
	289	itrace_derived_probe_group::emit_module_exit (systemtap_session& s)
	290	{
	291	if (probes_by_path.empty() && probes_by_pid.empty()) return;
	292	s.op->newline();
	293	s.op->newline() << "/* ---- itrace probes ---- */";
	294	s.op->newline() << "cleanup_usr_itrace();";
	295	}
	296
	297	void
	298	register_tapset_itrace(systemtap_session& s)
	299	{
	300	match_node* root = s.pattern_root;
	301	derived_probe_builder *builder = new itrace_builder();
	302
d2c9ec9b	303	root->bind_str(TOK_PROCESS)->bind(TOK_INSN)
d2c9ec9b DB	304	->bind(builder);
d2c9ec9b DB	305	root->bind_num(TOK_PROCESS)->bind(TOK_INSN)
d2c9ec9b DB	306	->bind(builder);
d2c9ec9b DB	307	root->bind_str(TOK_PROCESS)->bind(TOK_INSN)->bind(TOK_BLOCK)
d2c9ec9b DB	308	->bind(builder);
d2c9ec9b DB	309	root->bind_num(TOK_PROCESS)->bind(TOK_INSN)->bind(TOK_BLOCK)
d2c9ec9b	310	->bind(builder);
93646f4d JS	311	}
	312
	313
	314
	315	/* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */