[Qemu-devel] [PATCH v6 15/22] instrument: Add event 'guest_cpu_exit'

[Lluís Vilanova]

Signed-off-by: Lluís Vilanova <address@hidden>
---
 instrument/control.c            |    9 +++++++++
 instrument/events.h             |    3 +++
 instrument/events.inc.h         |   11 +++++++++++
 instrument/load.c               |   17 +++++++++++++++++
 instrument/qemu-instr/control.h |   11 +++++++++++
 stubs/instrument.c              |    1 +
 trace/control.c                 |    4 +++-
 7 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/instrument/control.c b/instrument/control.c
index 4f9c138ccf..7ed4bf3505 100644
--- a/instrument/control.c
+++ b/instrument/control.c
@@ -125,3 +125,12 @@ SYM_PUBLIC void qi_event_set_guest_cpu_enter(void 
(*fn)(QICPU vcpu))
     ERROR_IF(!instr_get_state(), "called outside instrumentation");
     instr_set_event(guest_cpu_enter, fn);
 }
+
+
+void (*instr_event__guest_cpu_exit)(QICPU vcpu);
+
+SYM_PUBLIC void qi_event_set_guest_cpu_exit(void (*fn)(QICPU vcpu))
+{
+    ERROR_IF(!instr_get_state(), "called outside instrumentation");
+    instr_set_event(guest_cpu_exit, fn);
+}
diff --git a/instrument/events.h b/instrument/events.h
index 947f120aa9..c743cb8180 100644
--- a/instrument/events.h
+++ b/instrument/events.h
@@ -36,6 +36,9 @@ extern void *instr_event__fini_data;
 extern void (*instr_event__guest_cpu_enter)(QICPU vcpu);
 static inline void instr_guest_cpu_enter(CPUState *vcpu);
 
+extern void (*instr_event__guest_cpu_exit)(QICPU vcpu);
+static inline void instr_guest_cpu_exit(CPUState *vcpu);
+
 
 #include "instrument/events.inc.h"
 
diff --git a/instrument/events.inc.h b/instrument/events.inc.h
index e3f8024716..c88df7e42f 100644
--- a/instrument/events.inc.h
+++ b/instrument/events.inc.h
@@ -20,3 +20,14 @@ static inline void instr_guest_cpu_enter(CPUState *vcpu)
         instr_set_state(INSTR_STATE_DISABLE);
     }
 }
+
+static inline void instr_guest_cpu_exit(CPUState *vcpu)
+{
+    void (*cb)(QICPU vcpu) = instr_get_event(guest_cpu_exit);
+    if (cb) {
+        QICPU vcpu_ = instr_cpu_to_qicpu(vcpu);
+        instr_set_state(INSTR_STATE_ENABLE);
+        (*cb)(vcpu_);
+        instr_set_state(INSTR_STATE_DISABLE);
+    }
+}
diff --git a/instrument/load.c b/instrument/load.c
index 218bca74b2..6808d361b5 100644
--- a/instrument/load.c
+++ b/instrument/load.c
@@ -11,7 +11,9 @@
 #include "qemu-common.h"
 
 #include <dlfcn.h>
+#include "cpu.h"
 #include "exec/cpu-common.h"
+#include "exec/exec-all.h"
 #include "instrument/control.h"
 #include "instrument/events.h"
 #include "instrument/load.h"
@@ -127,6 +129,13 @@ out:
     return res;
 }
 
+
+static void instr_unload__cb(CPUState *cpu, void *data)
+{
+    tb_flush_sync(cpu);
+    instr_guest_cpu_exit(cpu);
+}
+
 InstrUnloadError instr_unload(const char *id)
 {
     InstrUnloadError res;
@@ -139,6 +148,10 @@ InstrUnloadError instr_unload(const char *id)
         goto out;
     }
 
+    InstrCPUStop info;
+    cpu_list_lock();
+    instr_cpu_stop_all_begin(&info, instr_unload__cb, NULL);
+
     qi_fini_fn fini_fn = instr_get_event(fini_fn);
     if (fini_fn) {
         void *fini_data = instr_get_event(fini_data);
@@ -147,6 +160,10 @@ InstrUnloadError instr_unload(const char *id)
 
     instr_set_event(fini_fn, NULL);
     instr_set_event(guest_cpu_enter, NULL);
+    instr_set_event(guest_cpu_exit, NULL);
+
+    instr_cpu_stop_all_end(&info);
+    cpu_list_unlock();
 
     /* this should never fail */
     if (dlclose(handle->dlhandle) < 0) {
diff --git a/instrument/qemu-instr/control.h b/instrument/qemu-instr/control.h
index f61e7a2b6e..107ee8afe0 100644
--- a/instrument/qemu-instr/control.h
+++ b/instrument/qemu-instr/control.h
@@ -85,6 +85,17 @@ void qi_set_fini(qi_fini_fn fn, void *data);
  */
 void qi_event_set_guest_cpu_enter(void (*fn)(QICPU vcpu));
 
+/*
+ * Hot-unplug a virtual (guest) CPU.
+ *
+ * Also triggered on each CPU when an instrumentation library is unloaded.
+ *
+ * Mode: user, softmmu
+ * Targets: all
+ * Time: exec
+ */
+void qi_event_set_guest_cpu_exit(void (*fn)(QICPU vcpu));
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/stubs/instrument.c b/stubs/instrument.c
index abed583a56..e7adea1aad 100644
--- a/stubs/instrument.c
+++ b/stubs/instrument.c
@@ -43,3 +43,4 @@ void qmp_instr_unload(const char *id, Error **errp)
 
 __thread InstrState instr_cur_state;
 void (*instr_event__guest_cpu_enter)(QICPU *vcpu);
+void (*instr_event__guest_cpu_exit)(QICPU *vcpu);
diff --git a/trace/control.c b/trace/control.c
index 82d8989c4d..946a0af818 100644
--- a/trace/control.c
+++ b/trace/control.c
@@ -1,13 +1,14 @@
 /*
  * Interface for configuring and controlling the state of tracing events.
  *
- * Copyright (C) 2011-2016 Lluís Vilanova <address@hidden>
+ * Copyright (C) 2011-2017 Lluís Vilanova <address@hidden>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  */
 
 #include "qemu/osdep.h"
+#include "instrument/events.h"
 #include "trace/control.h"
 #include "qemu/help_option.h"
 #ifdef CONFIG_TRACE_SIMPLE
@@ -272,6 +273,7 @@ void trace_fini_vcpu(CPUState *vcpu)
     TraceEventIter iter;
     TraceEvent *ev;
 
+    instr_guest_cpu_exit(vcpu);
     trace_guest_cpu_exit(vcpu);
 
     trace_event_iter_init(&iter, NULL);