summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--ChangeLog8
-rw-r--r--runtime/ChangeLog8
-rw-r--r--runtime/task_finder.c120
-rw-r--r--tapsets.cxx114
4 files changed, 121 insertions, 129 deletions
diff --git a/ChangeLog b/ChangeLog
index 2a8b62c5..2770a938 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2008-08-29 David Smith <dsmith@redhat.com>
+
+ * tapsets.cxx (utrace_derived_probe_group::emit_probe_decl):
+ Pushed quiesce logic down into the task_finder layer.
+ (utrace_derived_probe_group::emit_module_decls): Removed quiesce
+ handler routines. Syscall probe handler detaches if systemtap
+ state isn't correct.
+
2008-08-29 Wenji Huang <wenji.huang@oracle.com>
* main.cxx (printscript): Print variable name and type for listing mode.
diff --git a/runtime/ChangeLog b/runtime/ChangeLog
index 926e05d9..b7e44a0f 100644
--- a/runtime/ChangeLog
+++ b/runtime/ChangeLog
@@ -1,3 +1,11 @@
+2008-08-29 David Smith <dsmith@redhat.com>
+
+ * task_finder.c (__stp_utrace_attach_match_filename): Don't call
+ the callback when the interesting thread is found, call it when
+ the tread is quiesced.
+ (stap_start_task_finder): Ditto.
+ (__stp_utrace_task_finder_target_quiesce): Call the callback.
+
2008-08-26 David Smith <dsmith@redhat.com>
* autoconf-d_path-path.c: New file.
diff --git a/runtime/task_finder.c b/runtime/task_finder.c
index af2345be..f1c2c41b 100644
--- a/runtime/task_finder.c
+++ b/runtime/task_finder.c
@@ -341,23 +341,41 @@ __stp_get_mm_path(struct mm_struct *mm, char *buf, int buflen)
return rc;
}
+/*
+ * All user threads get an engine with __STP_TASK_FINDER_EVENTS events
+ * attached to it so the task_finder layer can monitor new thread
+ * creation/death.
+ */
#define __STP_TASK_FINDER_EVENTS (UTRACE_EVENT(CLONE) \
| UTRACE_EVENT(EXEC) \
| UTRACE_EVENT(DEATH))
-#define __STP_ATTACHED_TASK_BASE_EVENTS (UTRACE_EVENT(DEATH))
-
-#define __STP_ATTACHED_TASK_VM_BASE_EVENTS (__STP_ATTACHED_TASK_BASE_EVENTS \
- | UTRACE_EVENT(SYSCALL_ENTRY) \
- | UTRACE_EVENT(SYSCALL_EXIT))
-
-#define __STP_ATTACHED_TASK_VM_EVENTS (__STP_ATTACHED_TASK_BASE_EVENTS \
- | UTRACE_STOP \
- | UTRACE_EVENT(QUIESCE))
-
-#define __STP_ATTACHED_TASK_EVENTS(tgt) \
- ((((tgt)->vm_callback) == NULL) ? __STP_ATTACHED_TASK_BASE_EVENTS \
- : __STP_ATTACHED_TASK_VM_EVENTS)
+/*
+ * __STP_TASK_BASE_EVENTS: base events for stap_task_finder_target's
+ * without a vm_callback
+ *
+ * __STP_TASK_VM_BASE_EVENTS: base events for
+ * stap_task_finder_target's with a vm_callback
+ */
+#define __STP_TASK_BASE_EVENTS (UTRACE_EVENT(DEATH))
+
+#define __STP_TASK_VM_BASE_EVENTS (__STP_TASK_BASE_EVENTS \
+ | UTRACE_EVENT(SYSCALL_ENTRY)\
+ | UTRACE_EVENT(SYSCALL_EXIT))
+
+/*
+ * All "interesting" threads get an engine with
+ * __STP_ATTACHED_TASK_EVENTS events attached to it. After the thread
+ * quiesces, we reset the events to __STP_ATTACHED_TASK_BASE_EVENTS
+ * events.
+ */
+#define __STP_ATTACHED_TASK_EVENTS (__STP_TASK_BASE_EVENTS \
+ | UTRACE_STOP \
+ | UTRACE_EVENT(QUIESCE))
+
+#define __STP_ATTACHED_TASK_BASE_EVENTS(tgt) \
+ ((((tgt)->vm_callback) == NULL) ? __STP_TASK_BASE_EVENTS \
+ : __STP_TASK_VM_BASE_EVENTS)
static int
stap_utrace_attach(struct task_struct *tsk,
@@ -444,31 +462,40 @@ __stp_utrace_attach_match_filename(struct task_struct *tsk,
if (cb_tgt == NULL)
continue;
- if (cb_tgt->callback != NULL) {
- int rc = cb_tgt->callback(cb_tgt, tsk,
- register_p,
- process_p);
- if (rc != 0) {
- _stp_error("callback for %d failed: %d",
- (int)tsk->pid, rc);
- break;
- }
- }
-
// Set up events we need for attached tasks.
+ // When register_p is set, we won't actually
+ // call the callback here - we'll call it when
+ // the thread gets quiesced. When register_p
+ // isn't set, we can go ahead and call the
+ // callback.
if (register_p) {
rc = stap_utrace_attach(tsk, &cb_tgt->ops,
cb_tgt,
- __STP_ATTACHED_TASK_EVENTS(cb_tgt));
+ __STP_ATTACHED_TASK_EVENTS);
if (rc != 0 && rc != EPERM)
break;
cb_tgt->engine_attached = 1;
}
else {
+ if (cb_tgt->callback != NULL) {
+ rc = cb_tgt->callback(cb_tgt, tsk,
+ register_p,
+ process_p);
+ if (rc != 0) {
+ _stp_error("callback for %d failed: %d",
+ (int)tsk->pid, rc);
+ break;
+ }
+ }
+
rc = stap_utrace_detach(tsk, &cb_tgt->ops);
if (rc != 0)
break;
- cb_tgt->engine_attached = 0;
+
+ // Note that we don't want to set
+ // engine_attached to 0 here - only
+ // when *all* threads using this
+ // engine have been detached.
}
}
}
@@ -685,18 +712,32 @@ __stp_utrace_task_finder_target_quiesce(enum utrace_resume_action action,
struct stap_task_finder_target *tgt = engine->data;
int rc;
- // Turn off quiesce handling (and turn on syscall handling).
- rc = utrace_set_events(tsk, engine, __STP_ATTACHED_TASK_VM_BASE_EVENTS);
+ if (atomic_read(&__stp_task_finder_state) != __STP_TF_RUNNING) {
+ debug_task_finder_detach();
+ return UTRACE_DETACH;
+ }
+
+ if (tgt == NULL)
+ return UTRACE_DETACH;
+
+ // Turn off quiesce handling
+ rc = utrace_set_events(tsk, engine,
+ __STP_ATTACHED_TASK_BASE_EVENTS(tgt));
if (rc != 0)
_stp_error("utrace_set_events returned error %d on pid %d",
rc, (int)tsk->pid);
- if (atomic_read(&__stp_task_finder_state) != __STP_TF_RUNNING) {
- debug_task_finder_detach();
- return UTRACE_DETACH;
+ if (tgt->callback != NULL) {
+ /* Call the callback. Assume that if the thread is a
+ * thread group leader, it is a process. */
+ rc = tgt->callback(tgt, tsk, 1, (tsk->pid == tsk->tgid));
+ if (rc != 0) {
+ _stp_error("callback for %d failed: %d",
+ (int)tsk->pid, rc);
+ }
}
- if (tgt != NULL && tgt->vm_callback != NULL) {
+ if (tgt->vm_callback != NULL) {
struct mm_struct *mm;
char *mmpath_buf;
char *mmpath;
@@ -1148,24 +1189,11 @@ stap_start_task_finder(void)
callback_list);
if (cb_tgt == NULL)
continue;
-
- // Call the callback. Assume that if
- // the thread is a thread group
- // leader, it is a process.
- if (cb_tgt->callback != NULL) {
- rc = cb_tgt->callback(cb_tgt, tsk, 1,
- (tsk->pid == tsk->tgid));
- if (rc != 0) {
- _stp_error("attach callback for %d failed: %d",
- (int)tsk->pid, rc);
- goto stf_err;
- }
- }
// Set up events we need for attached tasks.
rc = stap_utrace_attach(tsk, &cb_tgt->ops,
cb_tgt,
- __STP_ATTACHED_TASK_EVENTS(cb_tgt));
+ __STP_ATTACHED_TASK_EVENTS);
if (rc != 0 && rc != EPERM)
goto stf_err;
cb_tgt->engine_attached = 1;
diff --git a/tapsets.cxx b/tapsets.cxx
index 289c5fac..aa6a611d 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -6073,17 +6073,13 @@ utrace_derived_probe_group::emit_probe_decl (systemtap_session& s,
// Handle flags
switch (p->flags)
{
- // Look in _stp_utrace_probe_cb for description of why quiesce is
- // used here.
+ // Notice that we'll just call the probe directly when we get
+ // notified, since the task_finder layer stops the thread for us.
case UDPF_BEGIN: // process begin
s.op->line() << " .flags=(UDPF_BEGIN),";
- s.op->line() << " .ops={ .report_quiesce=stap_utrace_probe_quiesce },";
- s.op->line() << " .events=(UTRACE_STOP|UTRACE_EVENT(QUIESCE)),";
break;
case UDPF_THREAD_BEGIN: // thread begin
s.op->line() << " .flags=(UDPF_THREAD_BEGIN),";
- s.op->line() << " .ops={ .report_quiesce=stap_utrace_probe_quiesce },";
- s.op->line() << " .events=(UTRACE_STOP|UTRACE_EVENT(QUIESCE)),";
break;
// Notice we're not setting up a .ops/.report_death handler for
@@ -6098,17 +6094,17 @@ utrace_derived_probe_group::emit_probe_decl (systemtap_session& s,
// For UDPF_SYSCALL/UDPF_SYSCALL_RETURN probes, the .report_death
// handler isn't strictly necessary. However, it helps to keep
- // our attaches/detaches symmetrical. Notice we're using quiesce
- // as a workaround for bug 6841.
+ // our attaches/detaches symmetrical. Since the task_finder layer
+ // stops the thread, that works around bug 6841.
case UDPF_SYSCALL:
s.op->line() << " .flags=(UDPF_SYSCALL),";
- s.op->line() << " .ops={ .report_syscall_entry=stap_utrace_probe_syscall, .report_death=stap_utrace_task_finder_report_death, .report_quiesce=stap_utrace_probe_syscall_quiesce },";
- s.op->line() << " .events=(UTRACE_STOP|UTRACE_EVENT(QUIESCE)|UTRACE_EVENT(DEATH)),";
+ s.op->line() << " .ops={ .report_syscall_entry=stap_utrace_probe_syscall, .report_death=stap_utrace_task_finder_report_death },";
+ s.op->line() << " .events=(UTRACE_EVENT(SYSCALL_ENTRY)|UTRACE_EVENT(DEATH)),";
break;
case UDPF_SYSCALL_RETURN:
s.op->line() << " .flags=(UDPF_SYSCALL_RETURN),";
- s.op->line() << " .ops={ .report_syscall_exit=stap_utrace_probe_syscall, .report_death=stap_utrace_task_finder_report_death, .report_quiesce=stap_utrace_probe_syscall_quiesce },";
- s.op->line() << " .events=(UTRACE_STOP|UTRACE_EVENT(QUIESCE)|UTRACE_EVENT(DEATH)),";
+ s.op->line() << " .ops={ .report_syscall_exit=stap_utrace_probe_syscall, .report_death=stap_utrace_task_finder_report_death },";
+ s.op->line() << " .events=(UTRACE_EVENT(SYSCALL_EXIT)|UTRACE_EVENT(DEATH)),";
break;
case UDPF_NONE:
@@ -6191,32 +6187,10 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->newline(-1) << "};";
- // Output handler function for UDPF_BEGIN and UDPF_THREAD_BEGIN
- if (flags_seen[UDPF_BEGIN] || flags_seen[UDPF_THREAD_BEGIN])
- {
- s.op->newline() << "#ifdef UTRACE_ORIG_VERSION";
- s.op->newline() << "static u32 stap_utrace_probe_quiesce(struct utrace_attached_engine *engine, struct task_struct *tsk) {";
- s.op->newline() << "#else";
- s.op->newline() << "static u32 stap_utrace_probe_quiesce(enum utrace_resume_action action, struct utrace_attached_engine *engine, struct task_struct *tsk, unsigned long event) {";
- s.op->newline() << "#endif";
- s.op->indent(1);
- s.op->newline() << "struct stap_utrace_probe *p = (struct stap_utrace_probe *)engine->data;";
-
- common_probe_entryfn_prologue (s.op, "STAP_SESSION_RUNNING");
- s.op->newline() << "c->probe_point = p->pp;";
-
- // call probe function
- s.op->newline() << "(*p->ph) (c);";
- common_probe_entryfn_epilogue (s.op);
-
- // we're detaching, so utrace automatically restarts the thread.
- s.op->newline() << "debug_task_finder_detach();";
- s.op->newline() << "return UTRACE_DETACH;";
- s.op->newline(-1) << "}";
- }
-
- // Output handler function for UDPF_END and UDPF_THREAD_END
- if (flags_seen[UDPF_END] || flags_seen[UDPF_THREAD_END])
+ // Output handler function for UDPF_BEGIN, UDPF_THREAD_BEGIN,
+ // UDPF_END, and UDPF_THREAD_END
+ if (flags_seen[UDPF_BEGIN] || flags_seen[UDPF_THREAD_BEGIN]
+ || flags_seen[UDPF_END] || flags_seen[UDPF_THREAD_END])
{
s.op->newline() << "static void stap_utrace_probe_handler(struct task_struct *tsk, struct stap_utrace_probe *p) {";
s.op->indent(1);
@@ -6236,33 +6210,6 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
if (flags_seen[UDPF_SYSCALL] || flags_seen[UDPF_SYSCALL_RETURN])
{
s.op->newline() << "#ifdef UTRACE_ORIG_VERSION";
- s.op->newline() << "static u32 stap_utrace_probe_syscall_quiesce(struct utrace_attached_engine *engine, struct task_struct *tsk) {";
- s.op->newline() << "#else";
- s.op->newline() << "static u32 stap_utrace_probe_syscall_quiesce(enum utrace_resume_action action, struct utrace_attached_engine *engine, struct task_struct *tsk, unsigned long event) {";
- s.op->newline() << "#endif";
- s.op->indent(1);
- s.op->newline() << "struct stap_utrace_probe *p = (struct stap_utrace_probe *)engine->data;";
- s.op->newline() << "int rc = 0;";
-
- // Turn off quiesce handling and turn on either syscall entry
- // or exit events.
- s.op->newline() << "if (p->flags == UDPF_SYSCALL)";
- s.op->indent(1);
- s.op->newline() << "rc = utrace_set_events(tsk, engine, UTRACE_EVENT(SYSCALL_ENTRY)|UTRACE_EVENT(DEATH));";
- s.op->indent(-1);
- s.op->newline() << "else if (p->flags == UDPF_SYSCALL_RETURN)";
- s.op->indent(1);
- s.op->newline() << "rc = utrace_set_events(tsk, engine, UTRACE_EVENT(SYSCALL_EXIT)|UTRACE_EVENT(DEATH));";
- s.op->indent(-1);
- s.op->newline() << "if (rc != 0)";
- s.op->indent(1);
- s.op->newline() << "_stp_error(\"utrace_set_events returned error %d on pid %d\", rc, (int)tsk->pid);";
- s.op->indent(-1);
-
- s.op->newline() << "return UTRACE_RESUME;";
- s.op->newline(-1) << "}";
-
- s.op->newline() << "#ifdef UTRACE_ORIG_VERSION";
s.op->newline() << "static u32 stap_utrace_probe_syscall(struct utrace_attached_engine *engine, struct task_struct *tsk, struct pt_regs *regs) {";
s.op->newline() << "#else";
s.op->newline() << "static u32 stap_utrace_probe_syscall(enum utrace_resume_action action, struct utrace_attached_engine *engine, struct task_struct *tsk, struct pt_regs *regs) {";
@@ -6279,6 +6226,11 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->newline() << "(*p->ph) (c);";
common_probe_entryfn_epilogue (s.op);
+ s.op->newline() << "if ((atomic_read (&session_state) != STAP_SESSION_STARTING) && (atomic_read (&session_state) != STAP_SESSION_RUNNING)) {";
+ s.op->indent(1);
+ s.op->newline() << "debug_task_finder_detach();";
+ s.op->newline() << "return UTRACE_DETACH;";
+ s.op->newline(-1) << "}";
s.op->newline() << "return UTRACE_RESUME;";
s.op->newline(-1) << "}";
}
@@ -6307,11 +6259,7 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->indent(1);
s.op->newline() << "if (process_p) {";
s.op->indent(1);
- s.op->newline() << "rc = stap_utrace_attach(tsk, &p->ops, p, p->events);";
- s.op->newline() << "if (rc == 0) {";
- s.op->indent(1);
- s.op->newline() << "p->engine_attached = 1;";
- s.op->newline(-1) << "}";
+ s.op->newline() << "stap_utrace_probe_handler(tsk, p);";
s.op->newline(-1) << "}";
s.op->newline() << "break;";
s.op->indent(-1);
@@ -6322,11 +6270,7 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->indent(1);
s.op->newline() << "if (! process_p) {";
s.op->indent(1);
- s.op->newline() << "rc = stap_utrace_attach(tsk, &p->ops, p, p->events);";
- s.op->newline() << "if (rc == 0) {";
- s.op->indent(1);
- s.op->newline() << "p->engine_attached = 1;";
- s.op->newline(-1) << "}";
+ s.op->newline() << "stap_utrace_probe_handler(tsk, p);";
s.op->newline(-1) << "}";
s.op->newline() << "break;";
s.op->indent(-1);
@@ -6367,7 +6311,8 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->newline(-1) << "}";
// Since this engine could be attached to multiple threads, don't
- // call stap_utrace_detach_ops() here.
+ // call stap_utrace_detach_ops() here, only call
+ // stap_utrace_detach() as necessary.
s.op->newline() << "else {";
s.op->indent(1);
s.op->newline() << "switch (p->flags) {";
@@ -6396,15 +6341,18 @@ utrace_derived_probe_group::emit_module_decls (systemtap_session& s)
s.op->indent(-1);
}
- // For begin/thread_begin probes, at deregistration time we'll try
- // to detach. This will only be necessary if the new thread/process
- // got killed before the probe got run in the UTRACE_EVENT(QUIESCE)
- // handler.
- if (flags_seen[UDPF_BEGIN] || flags_seen[UDPF_THREAD_BEGIN]
- || flags_seen[UDPF_SYSCALL] || flags_seen[UDPF_SYSCALL_RETURN])
- {
+ // For begin/thread_begin probes, we don't need to do anything.
+ if (flags_seen[UDPF_BEGIN] || flags_seen[UDPF_THREAD_BEGIN])
+ {
s.op->newline() << "case UDPF_BEGIN:";
s.op->newline() << "case UDPF_THREAD_BEGIN:";
+ s.op->indent(1);
+ s.op->newline() << "break;";
+ s.op->indent(-1);
+ }
+
+ if (flags_seen[UDPF_SYSCALL] || flags_seen[UDPF_SYSCALL_RETURN])
+ {
s.op->newline() << "case UDPF_SYSCALL:";
s.op->newline() << "case UDPF_SYSCALL_RETURN:";
s.op->indent(1);
generated by cgit (git 2.34.1) at 2025-08-05 11:12:23 +0000