xref: /openbmc/qemu/trace/control-target.c (revision 7d87775f)
1 /*
2  * Interface for configuring and controlling the state of tracing events.
3  *
4  * Copyright (C) 2014-2017 Lluís Vilanova <vilanova@ac.upc.edu>
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  */
9 
10 #include "qemu/osdep.h"
11 #include "qemu/lockable.h"
12 #include "cpu.h"
13 #include "trace/control.h"
14 
15 
16 void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
17 {
18     bool state_pre;
19     assert(trace_event_get_state_static(ev));
20     /*
21      * We ignore the "vcpu" property here, since no vCPUs have been created
22      * yet. Then dstate can only be 1 or 0.
23      */
24     state_pre = *ev->dstate;
25     if (state_pre != state) {
26         if (state) {
27             trace_events_enabled_count++;
28             *ev->dstate = 1;
29         } else {
30             trace_events_enabled_count--;
31             *ev->dstate = 0;
32         }
33     }
34 }
35 
36 void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
37 {
38     assert(trace_event_get_state_static(ev));
39 
40     /*
41      * There is no longer a "vcpu" property, dstate can only be 1 or
42      * 0. With it, we haven't instantiated any vCPU yet, so we will
43      * set a global state instead, and trace_init_vcpu will reconcile
44      * it afterwards.
45      */
46     bool state_pre = *ev->dstate;
47     if (state_pre != state) {
48         if (state) {
49             trace_events_enabled_count++;
50             *ev->dstate = 1;
51         } else {
52             trace_events_enabled_count--;
53             *ev->dstate = 0;
54         }
55     }
56 }
57