Commit 2bfe11c8 authored by Lluís Vilanova's avatar Lluís Vilanova Committed by Stefan Hajnoczi
Browse files

trace: Properly initialize dynamic event states in hot-plugged vCPUs 



Every time a vCPU is hot-plugged, it will "inherit" its tracing state
from the global state array. That is, if *any* existing vCPU has an
event enabled, new vCPUs will have too.

Signed-off-by: default avatarLluís Vilanova <vilanova@ac.upc.edu>
Message-id: 147428970768.15111.7664565956870423529.stgit@fimbulvetr.bsc.es
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 331f5eb2

bsd-user/main.c

+0 −1
Original line number Diff line number Diff line
@@ -1133,7 +1133,6 @@ int main(int argc, char **argv) 
        gdbserver_start (gdbstub_port);

        gdb_handlesig(cpu, 0);

    }

    trace_init_vcpu_events();

    cpu_loop(env);

    /* never exits */

    return 0;

linux-user/main.c

+0 −1
Original line number Diff line number Diff line
@@ -4800,7 +4800,6 @@ int main(int argc, char **argv, char **envp) 
        }

        gdb_handlesig(cpu, 0);

    }

    trace_init_vcpu_events();

    cpu_loop(env);

    /* never exits */

    return 0;

qom/cpu.c

+3 −0
Original line number Diff line number Diff line
@@ -333,6 +333,9 @@ static void cpu_common_realizefn(DeviceState *dev, Error **errp) 
        cpu_synchronize_post_init(cpu);

        cpu_resume(cpu);

    }



    /* NOTE: latest generic point where the cpu is fully realized */

    trace_init_vcpu(cpu);

}



static void cpu_common_initfn(Object *obj)

stubs/trace-control.c

+6 −0
Original line number Diff line number Diff line
@@ -44,3 +44,9 @@ void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, 
    /* should never be called on non-target binaries */

    abort();

}



void trace_init_vcpu(CPUState *vcpu)

{

    /* should never be called on non-target binaries */

    abort();

}

trace/control-target.c

+37 −0
Original line number Diff line number Diff line
@@ -81,3 +81,40 @@ void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, 
        }

    }

}



static bool adding_first_cpu(void)

{

    CPUState *cpu;

    size_t count = 0;

    CPU_FOREACH(cpu) {

        count++;

        if (count > 1) {

            return false;

        }

    }

    return true;

}



void trace_init_vcpu(CPUState *vcpu)

{

    TraceEvent *ev = NULL;



    while ((ev = trace_event_pattern("*", ev)) != NULL) {

        if (trace_event_is_vcpu(ev) &&

            trace_event_get_state_static(ev) &&

            trace_event_get_state_dynamic(ev)) {

            TraceEventID id = trace_event_get_id(ev);

            if (adding_first_cpu()) {

                /* check preconditions */

                assert(trace_events_dstate[id] == 1);

                /* disable early-init state ... */

                trace_events_dstate[id] = 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);

            }

        }

    }

}