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-rw-r--r--tapsets.cxx359
1 files changed, 355 insertions, 4 deletions
diff --git a/tapsets.cxx b/tapsets.cxx
index 22aae041..0711411e 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -3040,7 +3040,6 @@ dwarf_derived_probe::saveargs(dwarf_query& q, Dwarf_Die* scope_die, dwarf_var_ex
if (null_die(scope_die))
return;
- stringstream argstream;
string type_name;
Dwarf_Die type_die;
@@ -5319,7 +5318,341 @@ kprobe_builder::build(systemtap_session & sess,
}
}
+// ------------------------------------------------------------------------
+// Hardware breakpoint based probes.
+// ------------------------------------------------------------------------
+
+static const string TOK_HWBKPT("data");
+static const string TOK_HWBKPT_WRITE("write");
+static const string TOK_HWBKPT_RW("rw");
+static const string TOK_LENGTH("length");
+
+#define HWBKPT_READ 0
+#define HWBKPT_WRITE 1
+#define HWBKPT_RW 2
+struct hwbkpt_derived_probe: public derived_probe
+{
+ hwbkpt_derived_probe (probe *base,
+ probe_point *location,
+ uint64_t addr,
+ string symname,
+ unsigned int len,
+ bool has_only_read_access,
+ bool has_only_write_access,
+ bool has_rw_access
+ );
+ Dwarf_Addr hwbkpt_addr;
+ string symbol_name;
+ unsigned int hwbkpt_access,hwbkpt_len;
+
+ void printsig (std::ostream &o) const;
+ void join_group (systemtap_session& s);
+};
+
+struct hwbkpt_derived_probe_group: public derived_probe_group
+{
+ unsigned int max_hwbkpt_probes_by_arch;
+
+private:
+ vector<hwbkpt_derived_probe*> hwbkpt_probes_vector;
+ typedef vector<hwbkpt_derived_probe*>::iterator h_p_v_iterator;
+
+public:
+ void enroll (hwbkpt_derived_probe* probe, systemtap_session& s);
+ void emit_module_decls (systemtap_session& s);
+ void emit_module_init (systemtap_session& s);
+ void emit_module_exit (systemtap_session& s);
+};
+
+hwbkpt_derived_probe::hwbkpt_derived_probe (probe *base,
+ probe_point *location,
+ uint64_t addr,
+ string symname,
+ unsigned int len,
+ bool has_only_read_access,
+ bool has_only_write_access,
+ bool has_rw_access
+ ):
+ derived_probe (base, location),
+ hwbkpt_addr (addr),
+ symbol_name (symname),
+ hwbkpt_len (len)
+{
+ this->tok = base->tok;
+
+ vector<probe_point::component*> comps;
+ comps.push_back (new probe_point::component(TOK_KERNEL));
+
+ if (hwbkpt_addr)
+ comps.push_back (new probe_point::component (TOK_HWBKPT, new literal_number(hwbkpt_addr)));
+ else
+ if (symbol_name.size())
+ comps.push_back (new probe_point::component (TOK_HWBKPT, new literal_string(symbol_name)));
+
+ comps.push_back (new probe_point::component (TOK_LENGTH, new literal_number(hwbkpt_len)));
+
+ if (has_only_read_access)
+ this->hwbkpt_access = HWBKPT_READ ;
+//TODO add code for comps.push_back for read, since this flag is not for x86
+
+ else
+ {
+ if (has_only_write_access)
+ {
+ this->hwbkpt_access = HWBKPT_WRITE ;
+ comps.push_back (new probe_point::component(TOK_HWBKPT_WRITE));
+ }
+ else
+ {
+ this->hwbkpt_access = HWBKPT_RW ;
+ comps.push_back (new probe_point::component(TOK_HWBKPT_RW));
+ }
+ }
+
+ this->sole_location()->components = comps;
+}
+
+void hwbkpt_derived_probe::printsig (ostream& o) const
+{
+ sole_location()->print (o);
+ printsig_nested (o);
+}
+
+void hwbkpt_derived_probe::join_group (systemtap_session& s)
+{
+ if (! s.hwbkpt_derived_probes) {
+ s.hwbkpt_derived_probes = new hwbkpt_derived_probe_group ();
+ if (s.architecture == "i386" || s.architecture == "x86_64" )
+ s.hwbkpt_derived_probes->max_hwbkpt_probes_by_arch = 4;
+ else {
+ //TODO: Add code for other archs too
+ s.hwbkpt_derived_probes->max_hwbkpt_probes_by_arch = 0;
+ throw semantic_error ("Hardware Breakpoints not supported on arch " + s.architecture);
+ }
+ }
+ s.hwbkpt_derived_probes->enroll (this, s);
+}
+
+void hwbkpt_derived_probe_group::enroll (hwbkpt_derived_probe* p, systemtap_session& s)
+{
+ if (hwbkpt_probes_vector.size() >= max_hwbkpt_probes_by_arch ) {
+ clog << "Warning:No of Hardware breakpoint probes in script exceeds "
+ << "the number of hardware breakpoints that the architecture "
+ << "can support : max " << max_hwbkpt_probes_by_arch
+ << " on " << s.architecture ;
+ }
+ hwbkpt_probes_vector.push_back (p);
+}
+
+void
+hwbkpt_derived_probe_group::emit_module_decls (systemtap_session& s)
+{
+ if (hwbkpt_probes_vector.empty()) return;
+
+ s.op->newline() << "/* ---- hwbkpt-based probes ---- */";
+
+ s.op->newline() << "#include <linux/perf_event.h>";
+ s.op->newline() << "#include <linux/hw_breakpoint.h>";
+ s.op->newline();
+
+ // Forward declare the master entry functions
+ s.op->newline() << "static int enter_hwbkpt_probe (struct perf_event *bp,";
+ s.op->line() << " int nmi,";
+ s.op->line() << " struct perf_sample_data *data,";
+ s.op->line() << " struct pt_regs *regs);";
+ // Emit the actual probe list.
+
+ s.op->newline() << "static struct perf_event_attr ";
+ s.op->newline() << "stap_hwbkpt_probe_array[" << hwbkpt_probes_vector.size() << "];";
+
+ s.op->newline() << "static struct perf_event **";
+ s.op->newline() << "stap_hwbkpt_ret_array[" << hwbkpt_probes_vector.size() << "];";
+ s.op->newline() << "static struct stap_hwbkpt_probe {";
+ s.op->newline() << "int registered_p:1;";
+// registered_p = 0 signifies a probe that failed registration
+// registered_p = 1 signifies a probe that got registered successfully
+
+ // Probe point & Symbol Names are mostly small and uniform enough
+ // to justify putting const char*.
+#define CALCIT(var) \
+ s.op->newline() << "const char * const " << #var << ";";
+ CALCIT(pp);
+ CALCIT(symbol);
+#undef CALCIT
+
+ s.op->newline() << "const unsigned long address;";
+ s.op->newline() << "uint8_t atype;";
+ s.op->newline() << "uint8_t len;";
+ s.op->newline() << "void (* const ph) (struct context*);";
+ s.op->newline() << "} stap_hwbkpt_probes[] = {";
+ s.op->indent(1);
+
+ for (unsigned int it = 0; it < hwbkpt_probes_vector.size(); it++)
+ {
+ hwbkpt_derived_probe* p = hwbkpt_probes_vector.at(it);
+ s.op->newline() << "{";
+ s.op->line() << " .registered_p=1,";
+ if (p->symbol_name.size())
+ s.op->line() << " .address=(unsigned long)0x0" << "ULL,";
+ else
+ s.op->line() << " .address=(unsigned long)0x" << hex << p->hwbkpt_addr << dec << "ULL,";
+ switch(p->hwbkpt_access){
+ case HWBKPT_READ:
+ s.op->line() << " .atype=HW_BREAKPOINT_R ,";
+ case HWBKPT_WRITE:
+ s.op->line() << " .atype=HW_BREAKPOINT_W ,";
+ case HWBKPT_RW:
+ s.op->line() << " .atype=HW_BREAKPOINT_R|HW_BREAKPOINT_W ,";
+ };
+ s.op->line() << " .len=" << p->hwbkpt_len << ",";
+ s.op->line() << " .pp=" << lex_cast_qstring (*p->sole_location()) << ",";
+ s.op->line() << " .symbol=\"" << p->symbol_name << "\",";
+ s.op->line() << " .ph=&" << p->name << "";
+ s.op->line() << " },";
+ }
+ s.op->newline() << "};";
+
+ // Emit the hwbkpt callback function
+ s.op->newline() ;
+ s.op->newline() << "static int enter_hwbkpt_probe (struct perf_event *bp,";
+ s.op->line() << " int nmi,";
+ s.op->line() << " struct perf_sample_data *data,";
+ s.op->line() << " struct pt_regs *regs) {";
+ s.op->newline() << "unsigned int i;";
+ s.op->newline() << "if (bp->attr.type != PERF_TYPE_BREAKPOINT )";
+ s.op->newline() << "return -1;";
+ s.op->newline() << "for ( i=0; i<" << hwbkpt_probes_vector.size() << "; i++) {";
+ s.op->newline() << "struct perf_event_attr *hp = & stap_hwbkpt_probe_array[i];";
+ s.op->newline() << "if (bp->attr.bp_addr==hp->bp_addr && bp->attr.bp_type==hp->bp_type && bp->attr.bp_len==hp->bp_len ) {";
+ s.op->newline() << "struct stap_hwbkpt_probe *sdp = &stap_hwbkpt_probes[i];";
+ common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING", "sdp->pp");
+ s.op->newline() << "c->regs = regs;";
+ s.op->newline() << "(*sdp->ph) (c);";
+ common_probe_entryfn_epilogue (s.op);
+ s.op->newline() << "return 0;";
+ s.op->newline() << "}";
+ s.op->newline(-1) << "}";
+ s.op->newline() << "return 0;";
+ s.op->newline() << "}";
+}
+
+void
+hwbkpt_derived_probe_group::emit_module_init (systemtap_session& s)
+{
+ s.op->newline() << "for (i=0; i<" << hwbkpt_probes_vector.size() << "; i++) {";
+ s.op->newline(1) << "struct stap_hwbkpt_probe *sdp = & stap_hwbkpt_probes[i];";
+ s.op->newline() << "struct perf_event_attr *hp = & stap_hwbkpt_probe_array[i];";
+ s.op->newline() << "void *addr = (void *) sdp->address;";
+ s.op->newline() << "const char *hwbkpt_symbol_name = addr ? NULL : sdp->symbol;";
+ s.op->newline() << " hw_breakpoint_init(hp);";
+ s.op->newline() << " if (addr) ";
+ s.op->newline() << " hp->bp_addr = (unsigned long) addr;";
+ s.op->newline() << " else { ";
+ s.op->newline() << " hp->bp_addr = kallsyms_lookup_name(hwbkpt_symbol_name);";
+ s.op->newline() << " if (!hp->bp_addr) { ";
+ s.op->newline() << " _stp_warn(\"Probe %s registration skipped : invalid symbol %s \",sdp->pp,hwbkpt_symbol_name);";
+ s.op->newline() << " sdp->registered_p = 0;";
+ s.op->newline() << " } ";
+ s.op->newline() << " } ";
+ if (s.architecture == "i386" || s.architecture == "x86_64" ) {
+ s.op->newline() << " switch(sdp->len) {";
+ s.op->newline() << " case 1:";
+ s.op->newline() << " hp->bp_len = HW_BREAKPOINT_LEN_1;";
+ s.op->newline() << " break;";
+ s.op->newline() << " case 2:";
+ s.op->newline() << " hp->bp_len = HW_BREAKPOINT_LEN_2;";
+ s.op->newline() << " break;";
+ s.op->newline() << " case 3:";
+ s.op->newline() << " case 4:";
+ s.op->newline() << " hp->bp_len = HW_BREAKPOINT_LEN_4;";
+ s.op->newline() << " break;";
+ s.op->newline() << " case 5:";
+ s.op->newline() << " case 6:";
+ s.op->newline() << " case 7:";
+ s.op->newline() << " case 8:";
+ s.op->newline() << " hp->bp_len = HW_BREAKPOINT_LEN_8;";
+ s.op->newline() << " break;";
+ s.op->newline() << " default:";
+ s.op->newline() << " _stp_warn(\"Probe %s registration skipped : unsupported length. Supported lengths for x86 are 1,2,4 {8 for x86_84 only} \",sdp->pp);";
+ s.op->newline() << " sdp->registered_p = 0;";
+ s.op->newline() << " }";
+ s.op->newline() << " hp->bp_type = sdp->atype;";
+ s.op->newline() << " if (sdp->atype == HW_BREAKPOINT_R) {";
+ s.op->newline() << " _stp_warn(\"Probe %s registration skipped : READ-ONLY hardware breakpoints not supported on x86\",sdp->pp);";
+ s.op->newline() << " sdp->registered_p = 0;";
+ s.op->newline() << " }";
+ } // end of x86 / x86_64 specific checks
+ s.op->newline() << "probe_point = sdp->pp;"; // for error messages
+ s.op->newline() << "if ( sdp->registered_p ) {";
+ s.op->newline() << " stap_hwbkpt_ret_array[i] = register_wide_hw_breakpoint( hp, (void *)&enter_hwbkpt_probe );";
+ s.op->newline() << " if (IS_ERR(stap_hwbkpt_ret_array[i])) {";
+ s.op->newline() << " int err_code = PTR_ERR(stap_hwbkpt_ret_array[i]);";
+ s.op->newline() << " sdp->registered_p = 0;";
+ s.op->newline(1) << " _stp_warn(\" Hwbkpt Probe %s : Registration error = %d, Addr = %p, name = %s\", probe_point, err_code, addr, hwbkpt_symbol_name);";
+ s.op->newline(-1) << " }";
+ s.op->newline() << " else sdp->registered_p = 1;";
+ s.op->newline() << "}";
+ s.op->newline(-1) << "}"; // for loop
+}
+
+void
+hwbkpt_derived_probe_group::emit_module_exit (systemtap_session& s)
+{
+ //Unregister hwbkpt probes.
+ s.op->newline() << "for (i=0; i<" << hwbkpt_probes_vector.size() << "; i++) {";
+ s.op->newline(1) << "struct stap_hwbkpt_probe *sdp = & stap_hwbkpt_probes[i];";
+ s.op->newline() << " if ( sdp->registered_p == 0 ) continue;";
+ s.op->newline() << " unregister_wide_hw_breakpoint(stap_hwbkpt_ret_array[i]);";
+ s.op->newline() << "sdp->registered_p = 0;";
+ s.op->newline(-1) << "}";
+}
+
+struct hwbkpt_builder: public derived_probe_builder
+{
+ hwbkpt_builder() {}
+ virtual void build(systemtap_session & sess,
+ probe * base,
+ probe_point * location,
+ literal_map_t const & parameters,
+ vector<derived_probe *> & finished_results);
+};
+
+void
+hwbkpt_builder::build(systemtap_session & sess,
+ probe * base,
+ probe_point * location,
+ literal_map_t const & parameters,
+ vector<derived_probe *> & finished_results)
+{
+ string symbol_str_val;
+ int64_t hwbkpt_address, len;
+ bool has_addr, has_symbol_str, has_write, has_rw, has_len;
+
+ has_addr = get_param (parameters, TOK_HWBKPT, hwbkpt_address);
+ has_symbol_str = get_param (parameters, TOK_HWBKPT, symbol_str_val);
+ has_len = get_param (parameters, TOK_LENGTH, len);
+ has_write = (parameters.find(TOK_HWBKPT_WRITE) != parameters.end());
+ has_rw = (parameters.find(TOK_HWBKPT_RW) != parameters.end());
+
+ if (!has_len)
+ len = 1;
+
+ if (has_addr)
+ finished_results.push_back (new hwbkpt_derived_probe (base,
+ location,
+ hwbkpt_address,
+ "",len,0,
+ has_write,
+ has_rw));
+ else // has symbol_str
+ finished_results.push_back (new hwbkpt_derived_probe (base,
+ location,
+ 0,
+ symbol_str_val,len,0,
+ has_write,
+ has_rw));
+}
// ------------------------------------------------------------------------
// statically inserted kernel-tracepoint derived probes
@@ -5811,7 +6144,7 @@ tracepoint_derived_probe_group::emit_module_decls (systemtap_session& s)
}
s.op->line() << ") {";
s.op->indent(1);
- common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING",
+ common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING",
lex_cast_qstring (*p->sole_location()));
s.op->newline() << "c->marker_name = "
<< lex_cast_qstring (p->tracepoint_name)
@@ -6140,7 +6473,6 @@ tracepoint_builder::init_dw(systemtap_session& s)
return true;
}
-
void
tracepoint_builder::build(systemtap_session& s,
probe *base, probe_point *location,
@@ -6158,7 +6490,6 @@ tracepoint_builder::build(systemtap_session& s,
}
-
// ------------------------------------------------------------------------
// Standard tapset registry.
// ------------------------------------------------------------------------
@@ -6205,6 +6536,25 @@ register_standard_tapsets(systemtap_session & s)
->bind_num(TOK_MAXACTIVE)->bind(new kprobe_builder());
s.pattern_root->bind(TOK_KPROBE)->bind_num(TOK_STATEMENT)
->bind(TOK_ABSOLUTE)->bind(new kprobe_builder());
+
+ //Hwbkpt based probe
+ if (s.kernel_config["CONFIG_PERF_EVENTS"] == string("y") &&
+ s.kernel_config["CONFIG_HAVE_HW_BREAKPOINT"] == string("y")) {
+ s.pattern_root->bind(TOK_KERNEL)->bind_num(TOK_HWBKPT)
+ ->bind(TOK_HWBKPT_WRITE)->bind(new hwbkpt_builder());
+ s.pattern_root->bind(TOK_KERNEL)->bind_str(TOK_HWBKPT)
+ ->bind(TOK_HWBKPT_WRITE)->bind(new hwbkpt_builder());
+ s.pattern_root->bind(TOK_KERNEL)->bind_num(TOK_HWBKPT)
+ ->bind(TOK_HWBKPT_RW)->bind(new hwbkpt_builder());
+ s.pattern_root->bind(TOK_KERNEL)->bind_str(TOK_HWBKPT)
+ ->bind(TOK_HWBKPT_RW)->bind(new hwbkpt_builder());
+ s.pattern_root->bind(TOK_KERNEL)->bind_num(TOK_HWBKPT)
+ ->bind_num(TOK_LENGTH)->bind(TOK_HWBKPT_WRITE)->bind(new hwbkpt_builder());
+ s.pattern_root->bind(TOK_KERNEL)->bind_num(TOK_HWBKPT)
+ ->bind_num(TOK_LENGTH)->bind(TOK_HWBKPT_RW)->bind(new hwbkpt_builder());
+ // length supported with address only, not symbol names
+ }
+
}
@@ -6231,6 +6581,7 @@ all_session_groups(systemtap_session& s)
DOONE(mark);
DOONE(tracepoint);
DOONE(kprobe);
+ DOONE(hwbkpt);
DOONE(hrtimer);
DOONE(perfmon);
DOONE(procfs);
generated by cgit (git 2.34.1) at 2025-08-02 14:45:28 +0000