Put common probe and session context state definitions in their own files.

translate.cxx contained code to produce the common probe and session
context state as C code snippets. Large parts were not dependent on the
session state at all, so they really were just static blobs of C code
wrapped in c++ io stream operators. These have been put in their own
C runtime header files (common_session_state.h, common_probe_context.h
and runtime_defines.h) to make it easier to edit and document.

diff --git a/runtime/common_probe_context.h b/runtime/common_probe_context.h
new file mode 100644 (file)
index 0000000..366cb59
--- /dev/null
+++ b/runtime/common_probe_context.h
@@ -0,0 +1,61 @@
+/* Included once by translate.cxx c_unparser::emit_common_header ()
+   Defines all common fields and probe flags for struct context.
+   Available to C-based probe handlers as fields of the CONTEXT ptr.  */
+
+atomic_t busy;
+const char *probe_point;
+const char *probe_name; /* as per 'stap -l' */
+int actionremaining;
+int nesting;
+string_t error_buffer;
+
+/* Only used when stap script uses tokenize.stp tapset.  */
+#ifdef STAP_NEED_CONTEXT_TOKENIZE
+string_t tok_str;
+char *tok_start;
+char *tok_end;
+#endif
+
+/* NB: last_error is used as a health flag within a probe.
+   While it's 0, execution continues
+   When it's "something", probe code unwinds, _stp_error's, sets error state */
+const char *last_error;
+const char *last_stmt;
+
+/* status of pt_regs regs field.  _STP_REGS_ flags.  */
+int regflags;
+struct pt_regs *regs;
+
+/* unwaddr is caching unwound address in each probe handler on ia64. */
+#if defined __ia64__
+unsigned long *unwaddr;
+#endif
+
+/* non-NULL when this probe was a kretprobe. */
+struct kretprobe_instance *pi;
+int pi_longs; /* int64_t count in pi->data, the rest is string_t */
+
+/* Only used when stap script uses the i386 or x86_64 register.stp tapset. */
+#ifdef STAP_NEED_REGPARM
+int regparm;
+#endif
+
+/* State for mark_derived_probes.  */
+va_list *mark_va_list;
+const char * marker_name;
+const char * marker_format;
+void *data;
+
+/* Only used for overload processing. */
+#ifdef STP_OVERLOAD
+cycles_t cycles_base;
+cycles_t cycles_sum;
+#endif
+
+/* non-NULL when this probe was a uretprobe. */
+struct uretprobe_instance *ri;
+
+/* Current state of the unwinder (as used in the unwind.c dwarf unwinder). */
+#if defined(STP_NEED_UNWIND_DATA)
+struct unwind_context uwcontext;
+#endif

diff --git a/runtime/common_session_state.h b/runtime/common_session_state.h
new file mode 100644 (file)
index 0000000..1cdf5b3
--- /dev/null
+++ b/runtime/common_session_state.h
@@ -0,0 +1,15 @@
+// Will be included once by translate.cxx c_unparser::emit_common_header ().
+
+#define STAP_SESSION_STARTING 0
+#define STAP_SESSION_RUNNING 1
+#define STAP_SESSION_ERROR 2
+#define STAP_SESSION_STOPPING 3
+#define STAP_SESSION_STOPPED 4
+static atomic_t session_state = ATOMIC_INIT (STAP_SESSION_STARTING);
+
+static atomic_t error_count = ATOMIC_INIT (0);
+static atomic_t skipped_count = ATOMIC_INIT (0);
+static atomic_t skipped_count_lowstack = ATOMIC_INIT (0);
+static atomic_t skipped_count_reentrant = ATOMIC_INIT (0);
+static atomic_t skipped_count_uprobe_reg = ATOMIC_INIT (0);
+static atomic_t skipped_count_uprobe_unreg = ATOMIC_INIT (0);

diff --git a/runtime/regs.h b/runtime/regs.h
index 08449aa6afb4c6f3b8eaa1013f8056465cc67c58..ca98c3126a0855d625f2d98853dded407239204b 100644 (file)
--- a/runtime/regs.h
+++ b/runtime/regs.h
@@ -11,6 +11,10 @@
 #ifndef _REGS_H_ /* -*- linux-c -*- */
 #define _REGS_H_
 
+/* Defines for the struct context regsflags field.
+   _STP_REGS_USER regsflags bit to indicate regs fully from user.  */
+#define _STP_REGS_USER_FLAG 1
+
 #if defined  (STAPCONF_X86_UNIREGS) && (defined (__x86_64__) || defined (__i386__))
 
 #define REG_IP(regs) regs->ip

diff --git a/runtime/runtime_defines.h b/runtime/runtime_defines.h
new file mode 100644 (file)
index 0000000..8eccc1e
--- /dev/null
+++ b/runtime/runtime_defines.h
@@ -0,0 +1,58 @@
+/* Common runtime defines, not dependend on session variables.
+   Included once at the top of the generated stap.c file by the translate.cxx
+   translate_pass ().  */
+
+/* Strings are used for storing backtraces, they are larger on 64bit
+   so raise the size on 64bit architectures. PR10486.  */
+#include <asm/types.h>
+#ifndef MAXSTRINGLEN
+#if BITS_PER_LONG == 32
+#define MAXSTRINGLEN 256
+#else
+#define MAXSTRINGLEN 512
+#endif
+#endif
+typedef char string_t[MAXSTRINGLEN];
+
+#ifndef MAXACTION
+#define MAXACTION 1000
+#endif
+#ifndef MAXACTION_INTERRUPTIBLE
+#define MAXACTION_INTERRUPTIBLE (MAXACTION * 10)
+#endif
+#ifndef TRYLOCKDELAY
+#define TRYLOCKDELAY 10 /* microseconds */
+#endif
+#ifndef MAXTRYLOCK
+#define MAXTRYLOCK 100 /* 1 millisecond total */
+#endif
+#ifndef MAXMAPENTRIES
+#define MAXMAPENTRIES 2048
+#endif
+#ifndef MAXERRORS
+#define MAXERRORS 0
+#endif
+#ifndef MAXSKIPPED
+#define MAXSKIPPED 100
+#endif
+#ifndef MINSTACKSPACE
+#define MINSTACKSPACE 1024
+#endif
+#ifndef INTERRUPTIBLE
+#define INTERRUPTIBLE 1
+#endif
+
+/* Overload processing.  */
+#ifndef STP_OVERLOAD_INTERVAL
+#define STP_OVERLOAD_INTERVAL 1000000000LL
+#endif
+#ifndef STP_OVERLOAD_THRESHOLD
+#define STP_OVERLOAD_THRESHOLD 500000000LL
+#endif
+
+/* We allow the user to completely turn overload processing off
+   (as opposed to tuning it by overriding the values above) by
+   running:  stap -DSTP_NO_OVERLOAD {other options}.  */
+#if !defined(STP_NO_OVERLOAD) && !defined(STAP_NO_OVERLOAD)
+#define STP_OVERLOAD
+#endif

diff --git a/translate.cxx b/translate.cxx
index caf9f32a880bd9f07ea804499d9ecde8728c0ac5..4b5f3d493ca351c888382833b3646f5f1f45eec2 100644 (file)
--- a/translate.cxx
+++ b/translate.cxx
@@ -913,69 +913,17 @@ translator_output::line ()
 void
 c_unparser::emit_common_header ()
 {
+  // Common (static atomic) state of the stap session.
   o->newline();
-  o->newline() << "typedef char string_t[MAXSTRINGLEN];";
-  o->newline();
-  o->newline() << "#define STAP_SESSION_STARTING 0";
-  o->newline() << "#define STAP_SESSION_RUNNING 1";
-  o->newline() << "#define STAP_SESSION_ERROR 2";
-  o->newline() << "#define STAP_SESSION_STOPPING 3";
-  o->newline() << "#define STAP_SESSION_STOPPED 4";
-  o->newline() << "static atomic_t session_state = ATOMIC_INIT (STAP_SESSION_STARTING);";
-  o->newline() << "static atomic_t error_count = ATOMIC_INIT (0);";
-  o->newline() << "static atomic_t skipped_count = ATOMIC_INIT (0);";
-  o->newline() << "static atomic_t skipped_count_lowstack = ATOMIC_INIT (0);";
-  o->newline() << "static atomic_t skipped_count_reentrant = ATOMIC_INIT (0);";
-  o->newline() << "static atomic_t skipped_count_uprobe_reg = ATOMIC_INIT (0);";
-  o->newline() << "static atomic_t skipped_count_uprobe_unreg = ATOMIC_INIT (0);";
-
-  // Defines for the regsflags field.
-  // _STP_REGS_USER regsflags bit to indicate regs fully from user.
-  o->newline();
-  o->newline() << "#define _STP_REGS_USER_FLAG 1";
-  o->newline();
+  o->newline() << "#include \"common_session_state.h\"";
 
+  // Per CPU context for probes. Includes common shared state held for
+  // all probes (defined in common_probe_context), the probe locals (union)
+  // and the function locals (union).
   o->newline() << "struct context {";
-  o->newline(1) << "atomic_t busy;";
-  o->newline() << "const char *probe_point;";
-  o->newline() << "const char *probe_name;"; // as per 'stap -l'
-  o->newline() << "int actionremaining;";
-  o->newline() << "int nesting;";
-  o->newline() << "string_t error_buffer;";
-  o->newline() << "#ifdef STAP_NEED_CONTEXT_TOKENIZE";
-  o->newline() << "string_t tok_str;";
-  o->newline() << "char *tok_start;";
-  o->newline() << "char *tok_end;";
-  o->newline() << "#endif";
-  o->newline() << "const char *last_error;";
-  // NB: last_error is used as a health flag within a probe.
-  // While it's 0, execution continues
-  // When it's "something", probe code unwinds, _stp_error's, sets error state
-  o->newline() << "const char *last_stmt;";
-  o->newline() << "struct pt_regs *regs;";
-  o->newline() << "#if defined __ia64__";
-  o->newline() << "unsigned long *unwaddr;";
-  // unwaddr is caching unwound address in each probe handler on ia64.
-  o->newline() << "#endif";
-  o->newline() << "struct kretprobe_instance *pi;";
-  o->newline() << "int pi_longs;"; // int64_t count in pi->data, the rest is string_t
-  o->newline() << "int regflags;"; // status of pt_regs regs field.
-  o->newline() << "#ifdef STAP_NEED_REGPARM"; // i386 or x86_64 register.stp
-  o->newline() << "int regparm;";
-  o->newline() << "#endif";
-  o->newline() << "va_list *mark_va_list;";
-  o->newline() << "const char * marker_name;";
-  o->newline() << "const char * marker_format;";
-  o->newline() << "void *data;";
-  o->newline() << "#ifdef STP_OVERLOAD";
-  o->newline() << "cycles_t cycles_base;";
-  o->newline() << "cycles_t cycles_sum;";
-  o->newline() << "#endif";
-  o->newline() << "struct uretprobe_instance *ri;";
 
-  o->newline() << "#if defined(STP_NEED_UNWIND_DATA)";
-  o->newline() << "struct unwind_context uwcontext;";
-  o->newline() << "#endif";
+  // Common state held shared by probes.
+  o->newline(1) << "#include \"common_probe_context.h\"";
 
   // PR10516: probe locals
   o->newline() << "union {";
@@ -5799,65 +5747,16 @@ translate_pass (systemtap_session& s)
       if (ri.recursive) nesting += 10;
 
       // This is at the very top of the file.
+      // All "static" defines (not dependend on session state).
+      s.op->newline() << "#include\"runtime_defines.h\"";
+
       if (! s.unprivileged)
        s.op->newline() << "#define STP_PRIVILEGED 1";
+
       s.op->newline() << "#ifndef MAXNESTING";
       s.op->newline() << "#define MAXNESTING " << nesting;
       s.op->newline() << "#endif";
 
-      // Strings are used for storing backtraces, they are larger on 64bit
-      // so raise the size on 64bit architectures. PR10486
-      s.op->newline() << "#include <asm/types.h>";
-      s.op->newline() << "#ifndef MAXSTRINGLEN";
-      s.op->newline() << "#if BITS_PER_LONG == 32";
-      s.op->newline() << "#define MAXSTRINGLEN 256";
-      s.op->newline() << "#else";
-      s.op->newline() << "#define MAXSTRINGLEN 512";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#endif";
-
-      s.op->newline() << "#ifndef MAXACTION";
-      s.op->newline() << "#define MAXACTION 1000";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MAXACTION_INTERRUPTIBLE";
-      s.op->newline() << "#define MAXACTION_INTERRUPTIBLE (MAXACTION * 10)";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef TRYLOCKDELAY";
-      s.op->newline() << "#define TRYLOCKDELAY 10 /* microseconds */";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MAXTRYLOCK";
-      s.op->newline() << "#define MAXTRYLOCK 100 /* 1 millisecond total */";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MAXMAPENTRIES";
-      s.op->newline() << "#define MAXMAPENTRIES 2048";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MAXERRORS";
-      s.op->newline() << "#define MAXERRORS 0";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MAXSKIPPED";
-      s.op->newline() << "#define MAXSKIPPED 100";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef MINSTACKSPACE";
-      s.op->newline() << "#define MINSTACKSPACE 1024";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef INTERRUPTIBLE";
-      s.op->newline() << "#define INTERRUPTIBLE 1";
-      s.op->newline() << "#endif";
-
-      // Overload processing
-      s.op->newline() << "#ifndef STP_OVERLOAD_INTERVAL";
-      s.op->newline() << "#define STP_OVERLOAD_INTERVAL 1000000000LL";
-      s.op->newline() << "#endif";
-      s.op->newline() << "#ifndef STP_OVERLOAD_THRESHOLD";
-      s.op->newline() << "#define STP_OVERLOAD_THRESHOLD 500000000LL";
-      s.op->newline() << "#endif";
-      // We allow the user to completely turn overload processing off
-      // (as opposed to tuning it by overriding the values above) by
-      // running:  stap -DSTP_NO_OVERLOAD {other options}
-      s.op->newline() << "#if !defined(STP_NO_OVERLOAD) && !defined(STAP_NO_OVERLOAD)";
-      s.op->newline() << "#define STP_OVERLOAD";
-      s.op->newline() << "#endif";
-
       s.op->newline() << "#define STP_SKIP_BADVARS " << (s.skip_badvars ? 1 : 0);
 
       if (s.bulk_mode)