Merge branch 'master' of ssh://sources.redhat.com/git/systemtap

5 files changed, 42 insertions, 10 deletions

diff --git a/runtime/loc2c-runtime.h b/runtime/loc2c-runtime.h
index 92c017d3..16ddb950 100644
--- a/runtime/loc2c-runtime.h
+++ b/runtime/loc2c-runtime.h
@@ -186,7 +186,7 @@
  */
 
 #define kread(ptr) ({ \
-        typeof(*(ptr)) _v; \
+        typeof(*(ptr)) _v = 0; \
         if (lookup_bad_addr((unsigned long)(ptr)) || \
             probe_kernel_read((void *)&_v, (void *)(ptr), sizeof(*(ptr)))) \
           DEREF_FAULT(ptr); \
@@ -202,14 +202,13 @@
     })
 
 #define deref(size, addr) ({ \
-    intptr_t _i; \
+    intptr_t _i = 0; \
     switch (size) { \
       case 1: _i = kread((u8 *)(addr)); break; \
       case 2: _i = kread((u16 *)(addr)); break; \
       case 4: _i = kread((u32 *)(addr)); break; \
       case 8: _i = kread((u64 *)(addr)); break; \
       default: __deref_bad(); \
-      /* uninitialized _i should also be caught by -Werror */ \
     } \
     _i; \
   })
@@ -235,7 +234,7 @@ extern void __store_deref_bad(void);
   ({									      \
     int _bad = 0;							      \
     u8 _b; u16 _w; u32 _l;	                                              \
-    intptr_t _v;							      \
+    intptr_t _v = 0;							      \
     if (lookup_bad_addr((unsigned long)addr))                                 \
       _bad = 1;                                                               \
     else                                                                      \
@@ -275,7 +274,7 @@ extern void __store_deref_bad(void);
   ({									      \
     int _bad = 0;							      \
     u8 _b; u16 _w; u32 _l; u64 _q;					      \
-    intptr_t _v;							      \
+    intptr_t _v = 0;							      \
     if (lookup_bad_addr((unsigned long)addr))                                 \
       _bad = 1;                                                               \
     else                                                                      \
@@ -392,7 +391,7 @@ extern void __store_deref_bad(void);
 #define deref(size, addr)						      \
   ({									      \
     int _bad = 0;							      \
-    intptr_t _v;							      \
+    intptr_t _v = 0;							      \
     if (lookup_bad_addr((unsigned long)addr))                                 \
       _bad = 1;                                                               \
     else                                                                      \
diff --git a/tapset/task.stp b/tapset/task.stp
index 07337156..f1a10b0a 100644
--- a/tapset/task.stp
+++ b/tapset/task.stp
@@ -63,6 +63,30 @@ function task_pid:long (task:long)
 }
 
 
+// Return the task of the given process id
+function pid2task:long (pid:long) %{ /* pure */
+    struct task_struct *t = NULL;
+    pid_t t_pid  = (pid_t)(long)THIS->pid;
+    rcu_read_lock();
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
+      t = find_task_by_vpid (t_pid);
+#else
+      t = find_task_by_pid (t_pid);
+#endif
+    rcu_read_unlock();
+    THIS->__retvalue = (long)t;
+    CATCH_DEREF_FAULT();
+%}
+
+// Return the name of the given process id
+function pid2execname:string (pid:long) { 
+    tsk = pid2task(pid)
+    if (tsk)
+	return task_execname(tsk)
+    return ""
+}
+
+
 // Return the thread id of the given task
 function task_tid:long (task:long)
 {
diff --git a/tapsets.cxx b/tapsets.cxx
index 6efcb3af..2f940b29 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -9770,8 +9770,13 @@ tracepoint_derived_probe_group::emit_module_decls (systemtap_session& s)
       s.op->newline(1) << "return register_trace_" << p->tracepoint_name
                        << "(enter_tracepoint_probe_" << i << ");";
       s.op->newline(-1) << "}";
-      s.op->newline() << "static int unregister_tracepoint_probe_" << i << "(void) {";
-      s.op->newline(1) << "return unregister_trace_" << p->tracepoint_name
+
+      // NB: we're not prepared to deal with unreg failures.  However, failures
+      // can only occur if the tracepoint doesn't exist (yet?), or if we
+      // weren't even registered.  The former should be OKed by the initial
+      // registration call, and the latter is safe to ignore.
+      s.op->newline() << "static void unregister_tracepoint_probe_" << i << "(void) {";
+      s.op->newline(1) << "(void) unregister_trace_" << p->tracepoint_name
                        << "(enter_tracepoint_probe_" << i << ");";
       s.op->newline(-1) << "}";
       s.op->newline();
@@ -9780,7 +9785,7 @@ tracepoint_derived_probe_group::emit_module_decls (systemtap_session& s)
   // emit an array of registration functions for easy init/shutdown
   s.op->newline() << "static struct stap_tracepoint_probe {";
   s.op->newline(1) << "int (*reg)(void);";
-  s.op->newline(0) << "int (*unreg)(void);";
+  s.op->newline(0) << "void (*unreg)(void);";
   s.op->newline(-1) << "} stap_tracepoint_probes[] = {";
   s.op->indent(1);
   for (unsigned i = 0; i < probes.size(); ++i)
diff --git a/testsuite/buildok/task-embedded.stp b/testsuite/buildok/task-embedded.stp
index 4d1f5300..d35f3e0d 100755
--- a/testsuite/buildok/task-embedded.stp
+++ b/testsuite/buildok/task-embedded.stp
@@ -14,6 +14,8 @@ probe begin {
 		task_nice (0) +
 		task_cpu (0) +
 		task_open_file_handles (0) +
-		task_max_file_handles (0))
+		task_max_file_handles (0) +
+		pid2task(0))
 	print (task_execname (0))
+	print (pid2execname (0))
 }
diff --git a/testsuite/buildok/task_test.stp b/testsuite/buildok/task_test.stp
index c8da7da5..792f96ea 100755
--- a/testsuite/buildok/task_test.stp
+++ b/testsuite/buildok/task_test.stp
@@ -16,5 +16,7 @@ probe begin {
   log(sprint(task_cpu(c)))
   log(sprint(task_open_file_handles(c)))
   log(sprint(task_max_file_handles(c)))
+  log(sprint(pid2task(pid())))
+  log(sprint(pid2execname(pid())))
   exit()
 }