/* * Interface for configuring and controlling the state of tracing events. * * Copyright (C) 2014-2017 LluĂs 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 "cpu.h" #include "trace-root.h" #include "trace/control.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) && likely(first_cpu != NULL)) { CPU_FOREACH(vcpu) { trace_event_set_vcpu_state_dynamic(vcpu, ev, state); } } else { /* * 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); cpu_tb_jmp_cache_clear(vcpu); } void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, TraceEvent *ev, bool state) { uint32_t vcpu_id; bool state_pre; assert(trace_event_get_state_static(ev)); assert(trace_event_is_vcpu(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_delayed); (*ev->dstate)++; } else { trace_events_enabled_count--; 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) { bool res; cpu_list_lock(); res = adding_first_cpu1(); cpu_list_unlock(); return res; } void trace_init_vcpu(CPUState *vcpu) { TraceEventIter iter; TraceEvent *ev; trace_event_iter_init(&iter, NULL); 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); }