1 /* 2 * Interface for configuring and controlling the state of tracing events. 3 * 4 * Copyright (C) 2014-2016 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 "cpu.h" 12 #include "trace.h" 13 #include "trace/control.h" 14 #include "translate-all.h" 15 16 17 void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state) 18 { 19 bool state_pre; 20 assert(trace_event_get_state_static(ev)); 21 /* 22 * We ignore the "vcpu" property here, since no vCPUs have been created 23 * yet. Then dstate can only be 1 or 0. 24 */ 25 state_pre = *ev->dstate; 26 if (state_pre != state) { 27 if (state) { 28 trace_events_enabled_count++; 29 *ev->dstate = 1; 30 } else { 31 trace_events_enabled_count--; 32 *ev->dstate = 0; 33 } 34 } 35 } 36 37 void trace_event_set_state_dynamic(TraceEvent *ev, bool state) 38 { 39 CPUState *vcpu; 40 assert(trace_event_get_state_static(ev)); 41 if (trace_event_is_vcpu(ev)) { 42 CPU_FOREACH(vcpu) { 43 trace_event_set_vcpu_state_dynamic(vcpu, ev, state); 44 } 45 } else { 46 /* Without the "vcpu" property, dstate can only be 1 or 0 */ 47 bool state_pre = *ev->dstate; 48 if (state_pre != state) { 49 if (state) { 50 trace_events_enabled_count++; 51 *ev->dstate = 1; 52 } else { 53 trace_events_enabled_count--; 54 *ev->dstate = 0; 55 } 56 } 57 } 58 } 59 60 void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, 61 TraceEvent *ev, bool state) 62 { 63 uint32_t vcpu_id; 64 bool state_pre; 65 assert(trace_event_get_state_static(ev)); 66 assert(trace_event_is_vcpu(ev)); 67 vcpu_id = trace_event_get_vcpu_id(ev); 68 state_pre = test_bit(vcpu_id, vcpu->trace_dstate); 69 if (state_pre != state) { 70 if (state) { 71 trace_events_enabled_count++; 72 set_bit(vcpu_id, vcpu->trace_dstate); 73 (*ev->dstate)++; 74 } else { 75 trace_events_enabled_count--; 76 clear_bit(vcpu_id, vcpu->trace_dstate); 77 (*ev->dstate)--; 78 } 79 } 80 } 81 82 static bool adding_first_cpu(void) 83 { 84 CPUState *cpu; 85 size_t count = 0; 86 CPU_FOREACH(cpu) { 87 count++; 88 if (count > 1) { 89 return false; 90 } 91 } 92 return true; 93 } 94 95 void trace_init_vcpu(CPUState *vcpu) 96 { 97 TraceEventIter iter; 98 TraceEvent *ev; 99 trace_event_iter_init(&iter, NULL); 100 while ((ev = trace_event_iter_next(&iter)) != NULL) { 101 if (trace_event_is_vcpu(ev) && 102 trace_event_get_state_static(ev) && 103 trace_event_get_state_dynamic(ev)) { 104 if (adding_first_cpu()) { 105 /* check preconditions */ 106 assert(*ev->dstate == 1); 107 /* disable early-init state ... */ 108 *ev->dstate = 0; 109 trace_events_enabled_count--; 110 /* ... and properly re-enable */ 111 trace_event_set_vcpu_state_dynamic(vcpu, ev, true); 112 } else { 113 trace_event_set_vcpu_state_dynamic(vcpu, ev, true); 114 } 115 } 116 } 117 trace_guest_cpu_enter(vcpu); 118 } 119