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 "cpu.h" 12 #include "trace-root.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) && likely(first_cpu != NULL)) { 42 CPU_FOREACH(vcpu) { 43 trace_event_set_vcpu_state_dynamic(vcpu, ev, state); 44 } 45 } else { 46 /* 47 * Without the "vcpu" property, dstate can only be 1 or 0. With it, we 48 * haven't instantiated any vCPU yet, so we will set a global state 49 * instead, and trace_init_vcpu will reconcile it afterwards. 50 */ 51 bool state_pre = *ev->dstate; 52 if (state_pre != state) { 53 if (state) { 54 trace_events_enabled_count++; 55 *ev->dstate = 1; 56 } else { 57 trace_events_enabled_count--; 58 *ev->dstate = 0; 59 } 60 } 61 } 62 } 63 64 void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, 65 TraceEvent *ev, bool state) 66 { 67 uint32_t vcpu_id; 68 bool state_pre; 69 assert(trace_event_get_state_static(ev)); 70 assert(trace_event_is_vcpu(ev)); 71 vcpu_id = trace_event_get_vcpu_id(ev); 72 state_pre = test_bit(vcpu_id, vcpu->trace_dstate); 73 if (state_pre != state) { 74 if (state) { 75 trace_events_enabled_count++; 76 set_bit(vcpu_id, vcpu->trace_dstate); 77 (*ev->dstate)++; 78 } else { 79 trace_events_enabled_count--; 80 clear_bit(vcpu_id, vcpu->trace_dstate); 81 (*ev->dstate)--; 82 } 83 } 84 } 85 86 static bool adding_first_cpu1(void) 87 { 88 CPUState *cpu; 89 size_t count = 0; 90 CPU_FOREACH(cpu) { 91 count++; 92 if (count > 1) { 93 return false; 94 } 95 } 96 return true; 97 } 98 99 static bool adding_first_cpu(void) 100 { 101 bool res; 102 cpu_list_lock(); 103 res = adding_first_cpu1(); 104 cpu_list_unlock(); 105 return res; 106 } 107 108 void trace_init_vcpu(CPUState *vcpu) 109 { 110 TraceEventIter iter; 111 TraceEvent *ev; 112 trace_event_iter_init(&iter, NULL); 113 while ((ev = trace_event_iter_next(&iter)) != NULL) { 114 if (trace_event_is_vcpu(ev) && 115 trace_event_get_state_static(ev) && 116 trace_event_get_state_dynamic(ev)) { 117 if (adding_first_cpu()) { 118 /* check preconditions */ 119 assert(*ev->dstate == 1); 120 /* disable early-init state ... */ 121 *ev->dstate = 0; 122 trace_events_enabled_count--; 123 /* ... and properly re-enable */ 124 trace_event_set_vcpu_state_dynamic(vcpu, ev, true); 125 } else { 126 trace_event_set_vcpu_state_dynamic(vcpu, ev, true); 127 } 128 } 129 } 130 trace_guest_cpu_enter(vcpu); 131 } 132