cpu: expose qemu_cpu_list_lock for lock-guard use

[mirror_qemu.git] / trace / control-target.c

diff --git a/trace/control-target.c b/trace/control-target.c
index 74c029acccb3e5f2a2489df72e4554b4279676fc..c0c1e2310a519642b61e1d727262ef1077ad6103 100644 (file)
--- a/trace/control-target.c
+++ b/trace/control-target.c
@@ -1,53 +1,148 @@
 /*
  * Interface for configuring and controlling the state of tracing events.
  *
- * Copyright (C) 2014-2016 Lluís Vilanova <vilanova@ac.upc.edu>
+ * Copyright (C) 2014-2017 Lluís Vilanova <vilanova@ac.upc.edu>
  *
  * 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 "qemu/lockable.h"
 #include "cpu.h"
+#include "trace/trace-root.h"
 #include "trace/control.h"
-#include "translate-all.h"
 
 
+void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
+{
+    bool state_pre;
+    assert(trace_event_get_state_static(ev));
+    /*
+     * We ignore the "vcpu" property here, since no vCPUs have been created
+     * yet. Then dstate can only be 1 or 0.
+     */
+    state_pre = *ev->dstate;
+    if (state_pre != state) {
+        if (state) {
+            trace_events_enabled_count++;
+            *ev->dstate = 1;
+        } else {
+            trace_events_enabled_count--;
+            *ev->dstate = 0;
+        }
+    }
+}
+
 void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
 {
     CPUState *vcpu;
     assert(trace_event_get_state_static(ev));
-    if (trace_event_is_vcpu(ev)) {
+    if (trace_event_is_vcpu(ev) && likely(first_cpu != NULL)) {
         CPU_FOREACH(vcpu) {
             trace_event_set_vcpu_state_dynamic(vcpu, ev, state);
         }
     } else {
-        TraceEventID id = trace_event_get_id(ev);
-        trace_events_enabled_count += state - trace_events_dstate[id];
-        trace_events_dstate[id] = state;
+        /*
+         * Without the "vcpu" property, dstate can only be 1 or 0. With it, we
+         * haven't instantiated any vCPU yet, so we will set a global state
+         * instead, and trace_init_vcpu will reconcile it afterwards.
+         */
+        bool state_pre = *ev->dstate;
+        if (state_pre != state) {
+            if (state) {
+                trace_events_enabled_count++;
+                *ev->dstate = 1;
+            } else {
+                trace_events_enabled_count--;
+                *ev->dstate = 0;
+            }
+        }
     }
 }
 
+static void trace_event_synchronize_vcpu_state_dynamic(
+    CPUState *vcpu, run_on_cpu_data ignored)
+{
+    bitmap_copy(vcpu->trace_dstate, vcpu->trace_dstate_delayed,
+                CPU_TRACE_DSTATE_MAX_EVENTS);
+    tcg_flush_jmp_cache(vcpu);
+}
+
 void trace_event_set_vcpu_state_dynamic(CPUState *vcpu,
                                         TraceEvent *ev, bool state)
 {
-    TraceEventID id;
-    TraceEventVCPUID vcpu_id;
+    uint32_t vcpu_id;
     bool state_pre;
     assert(trace_event_get_state_static(ev));
     assert(trace_event_is_vcpu(ev));
-    id = trace_event_get_id(ev);
     vcpu_id = trace_event_get_vcpu_id(ev);
     state_pre = test_bit(vcpu_id, vcpu->trace_dstate);
     if (state_pre != state) {
         if (state) {
             trace_events_enabled_count++;
-            set_bit(vcpu_id, vcpu->trace_dstate);
-            trace_events_dstate[id]++;
+            set_bit(vcpu_id, vcpu->trace_dstate_delayed);
+            (*ev->dstate)++;
         } else {
             trace_events_enabled_count--;
-            clear_bit(vcpu_id, vcpu->trace_dstate);
-            trace_events_dstate[id]--;
+            clear_bit(vcpu_id, vcpu->trace_dstate_delayed);
+            (*ev->dstate)--;
+        }
+        if (vcpu->created) {
+            /*
+             * Delay changes until next TB; we want all TBs to be built from a
+             * single set of dstate values to ensure consistency of generated
+             * tracing code.
+             */
+            async_run_on_cpu(vcpu, trace_event_synchronize_vcpu_state_dynamic,
+                             RUN_ON_CPU_NULL);
+        } else {
+            trace_event_synchronize_vcpu_state_dynamic(vcpu, RUN_ON_CPU_NULL);
+        }
+    }
+}
+
+static bool adding_first_cpu1(void)
+{
+    CPUState *cpu;
+    size_t count = 0;
+    CPU_FOREACH(cpu) {
+        count++;
+        if (count > 1) {
+            return false;
+        }
+    }
+    return true;
+}
+
+static bool adding_first_cpu(void)
+{
+    QEMU_LOCK_GUARD(&qemu_cpu_list_lock);
+
+    return adding_first_cpu1();
+}
+
+void trace_init_vcpu(CPUState *vcpu)
+{
+    TraceEventIter iter;
+    TraceEvent *ev;
+    trace_event_iter_init_all(&iter);
+    while ((ev = trace_event_iter_next(&iter)) != NULL) {
+        if (trace_event_is_vcpu(ev) &&
+            trace_event_get_state_static(ev) &&
+            trace_event_get_state_dynamic(ev)) {
+            if (adding_first_cpu()) {
+                /* check preconditions */
+                assert(*ev->dstate == 1);
+                /* disable early-init state ... */
+                *ev->dstate = 0;
+                trace_events_enabled_count--;
+                /* ... and properly re-enable */
+                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
+            } else {
+                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
+            }
         }
     }
+    trace_guest_cpu_enter(vcpu);
 }