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[PATCH 1/2] marker probe: $name support (Re: [RFC] sample test script and tapset for markers)
- From: Masami Hiramatsu <mhiramat at redhat dot com>
- To: "Frank Ch. Eigler" <fche at redhat dot com>, systemtap-ml <systemtap at sources dot redhat dot com>
- Cc: Hideo AOKI <haoki at redhat dot com>, Takahiro Yasui <tyasui at redhat dot com>
- Date: Fri, 05 Sep 2008 11:32:24 -0400
- Subject: [PATCH 1/2] marker probe: $name support (Re: [RFC] sample test script and tapset for markers)
- References: <48B42A17.1080106@redhat.com> <y0mhc97y59m.fsf@ton.toronto.redhat.com>
Hi,
Frank Ch. Eigler wrote:
> Masami Hiramatsu <mhiramat@redhat.com> writes:
>
>> [...]
>> * Each marker has "name" variable which stores marker name.
>
> It is unfortunate to have to hand-code this. It would be easy for the
> translator to provide the marker name as a $context variable.
Here is a patch which add $name variable access from marker probe.
I added _stp_mark_context structure which contains .name and .format
strings for passing both of them to marker handler. Now you can get
both of $format and $name from marker probes.
Thank you,
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division
e-mail: mhiramat@redhat.com
---
runtime/mark.h | 16 ++++++++++++++
tapset/marker.stp | 25 ++++++++++++++++++++++
tapsets.cxx | 60 ++++++++++++++++++++++--------------------------------
3 files changed, 66 insertions(+), 35 deletions(-)
Index: systemtap/tapsets.cxx
===================================================================
--- systemtap.orig/tapsets.cxx 2008-09-04 11:29:52.000000000 -0400
+++ systemtap/tapsets.cxx 2008-09-04 11:29:57.000000000 -0400
@@ -7753,7 +7753,7 @@
void visit_target_symbol (target_symbol* e);
void visit_target_symbol_arg (target_symbol* e);
- void visit_target_symbol_format (target_symbol* e);
+ void visit_target_symbol_context (target_symbol* e);
};
@@ -7860,48 +7860,37 @@
void
-mark_var_expanding_copy_visitor::visit_target_symbol_format (target_symbol* e)
+mark_var_expanding_copy_visitor::visit_target_symbol_context (target_symbol* e)
{
- static bool function_synthesized = false;
+ string sname = e->base_name;
if (is_active_lvalue (e))
- throw semantic_error("write to marker format not permitted", e->tok);
+ throw semantic_error("write to marker '" + sname + "' not permitted", e->tok);
if (e->components.size() > 0)
{
switch (e->components[0].first)
{
case target_symbol::comp_literal_array_index:
- throw semantic_error("marker format may not be used as array",
+ throw semantic_error("marker '" + sname + "' may not be used as array",
e->tok);
break;
case target_symbol::comp_struct_member:
- throw semantic_error("marker format may not be used as a structure",
+ throw semantic_error("marker '" + sname + "' may not be used as a structure",
e->tok);
break;
default:
- throw semantic_error ("invalid marker format use", e->tok);
+ throw semantic_error ("invalid marker '" + sname + "' use", e->tok);
break;
}
}
- string fname = string("_mark_format_get");
-
- // Synthesize a function (if not already synthesized).
- if (! function_synthesized)
- {
- function_synthesized = true;
- functiondecl *fdecl = new functiondecl;
- fdecl->tok = e->tok;
- embeddedcode *ec = new embeddedcode;
- ec->tok = e->tok;
-
- ec->code = string("strlcpy (THIS->__retvalue, CONTEXT->data, MAXSTRINGLEN); /* pure */");
- fdecl->name = fname;
- fdecl->body = ec;
- fdecl->type = pe_string;
- sess.functions.push_back(fdecl);
- }
+ string fname;
+ if (e->base_name == "$format") {
+ fname = string("_mark_format_get");
+ } else {
+ fname = string("_mark_name_get");
+ }
// Synthesize a functioncall.
functioncall* n = new functioncall;
@@ -7918,10 +7907,10 @@
if (e->base_name.substr(0,4) == "$arg")
visit_target_symbol_arg (e);
- else if (e->base_name == "$format")
- visit_target_symbol_format (e);
+ else if (e->base_name == "$format" || e->base_name == "$name")
+ visit_target_symbol_context (e);
else
- throw semantic_error ("invalid target symbol for marker, $argN or $format expected",
+ throw semantic_error ("invalid target symbol for marker, $argN, $name or $format expected",
e->tok);
}
@@ -8108,7 +8097,8 @@
ec->code = string("#if ! defined(CONFIG_MARKERS)\n")
+ string("#error \"Need CONFIG_MARKERS!\"\n")
+ string("#endif\n")
- + string("#include <linux/marker.h>\n");
+ + string("#include <linux/marker.h>\n")
+ + string("#include \"mark.h\"\n");
s.embeds.push_back(ec);
}
@@ -8191,8 +8181,7 @@
s.op->newline() << "/* ---- marker probes ---- */";
s.op->newline() << "struct stap_marker_probe {";
- s.op->newline(1) << "const char * const name;";
- s.op->newline() << "const char * const format;";
+ s.op->newline(1) << "struct _stp_mark_context mark;";
s.op->newline() << "const char * const pp;";
s.op->newline() << "void (* const ph) (struct context *);";
@@ -8201,10 +8190,11 @@
for (unsigned i=0; i < probes.size(); i++)
{
s.op->newline () << "{";
+ s.op->line() << " .mark = {";
s.op->line() << " .name=" << lex_cast_qstring(probes[i]->probe_name)
<< ",";
s.op->line() << " .format=" << lex_cast_qstring(probes[i]->probe_format)
- << ",";
+ << " },";
s.op->line() << " .pp=" << lex_cast_qstring (*probes[i]->sole_location())
<< ",";
s.op->line() << " .ph=&" << probes[i]->name;
@@ -8220,7 +8210,7 @@
s.op->newline(1) << "struct stap_marker_probe *smp = (struct stap_marker_probe *)probe_data;";
common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING");
s.op->newline() << "c->probe_point = smp->pp;";
- s.op->newline() << "c->data = (char *)smp->format;";
+ s.op->newline() << "c->data = (void *)&smp->mark;";
s.op->newline() << "c->mark_va_list = args;";
s.op->newline() << "(*smp->ph) (c);";
@@ -8244,11 +8234,11 @@
s.op->newline() << "for (i=0; i<" << probes.size() << "; i++) {";
s.op->newline(1) << "struct stap_marker_probe *smp = &stap_marker_probes[i];";
s.op->newline() << "probe_point = smp->pp;";
- s.op->newline() << "rc = marker_probe_register(smp->name, smp->format, enter_marker_probe, smp);";
+ s.op->newline() << "rc = marker_probe_register(smp->mark.name, smp->mark.format, enter_marker_probe, smp);";
s.op->newline() << "if (rc) {";
s.op->newline(1) << "for (j=i-1; j>=0; j--) {"; // partial rollback
s.op->newline(1) << "struct stap_marker_probe *smp2 = &stap_marker_probes[j];";
- s.op->newline() << "marker_probe_unregister(smp2->name, enter_marker_probe, smp2);";
+ s.op->newline() << "marker_probe_unregister(smp2->mark.name, enter_marker_probe, smp2);";
s.op->newline(-1) << "}";
s.op->newline() << "break;"; // don't attempt to register any more probes
s.op->newline(-1) << "}";
@@ -8265,7 +8255,7 @@
s.op->newline() << "/* deregister marker probes */";
s.op->newline() << "for (i=0; i<" << probes.size() << "; i++) {";
s.op->newline(1) << "struct stap_marker_probe *smp = &stap_marker_probes[i];";
- s.op->newline() << "marker_probe_unregister(smp->name, enter_marker_probe, smp);";
+ s.op->newline() << "marker_probe_unregister(smp->mark.name, enter_marker_probe, smp);";
s.op->newline(-1) << "}"; // for loop
}
Index: systemtap/runtime/mark.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ systemtap/runtime/mark.h 2008-09-04 11:29:57.000000000 -0400
@@ -0,0 +1,16 @@
+/* marker support header
+ *
+ * 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.
+ */
+#ifndef _STP_MARK_H_
+#define _STP_MARK_H_
+
+struct _stp_mark_context {
+ const char * const name;
+ const char * const format;
+};
+
+#endif
Index: systemtap/tapset/marker.stp
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ systemtap/tapset/marker.stp 2008-09-04 11:29:57.000000000 -0400
@@ -0,0 +1,25 @@
+//
+// kernel marker tapset
+//
+// 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.
+
+/* marker-only context accessors */
+
+%{
+#include "mark.h"
+%}
+
+function _mark_name_get:string () %{
+ strlcpy (THIS->__retvalue,
+ ((struct _stp_mark_context *)(CONTEXT->data))->name,
+ MAXSTRINGLEN); /* pure */
+%}
+
+function _mark_format_get:string () %{
+ strlcpy (THIS->__retvalue,
+ ((struct _stp_mark_context *)(CONTEXT->data))->format,
+ MAXSTRINGLEN); /* pure */
+%}