From d43811165df75571055dab7b602526a40404a63e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Llu=C3=ADs=20Vilanova?= Date: Tue, 4 Jul 2017 10:38:26 +0200 Subject: [PATCH] trace: [tcg] Delay changes to dynamic state when translating MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This keeps consistency across all decisions taken during translation when the dynamic state of a vCPU is changed in the middle of translating some guest code. Signed-off-by: Lluís Vilanova Reviewed-by: Richard Henderson Reviewed-by: Emilio G. Cota Signed-off-by: Emilio G. Cota Message-id: 149915750615.6295.3713699402253529487.stgit@frigg.lan Signed-off-by: Stefan Hajnoczi --- include/qom/cpu.h | 3 +++ trace/control-target.c | 18 ++++++++++++++++-- 2 files changed, 19 insertions(+), 2 deletions(-) diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 5f188d4c28..25eefea7ab 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -302,6 +302,8 @@ struct qemu_work_item; * @kvm_fd: vCPU file descriptor for KVM. * @work_mutex: Lock to prevent multiple access to queued_work_*. * @queued_work_first: First asynchronous work pending. + * @trace_dstate_delayed: Delayed changes to trace_dstate (includes all changes + * to @trace_dstate). * @trace_dstate: Dynamic tracing state of events for this vCPU (bitmask). * * State of one CPU core or thread. @@ -372,6 +374,7 @@ struct CPUState { struct kvm_run *kvm_run; /* Used for events with 'vcpu' and *without* the 'disabled' properties */ + DECLARE_BITMAP(trace_dstate_delayed, CPU_TRACE_DSTATE_MAX_EVENTS); DECLARE_BITMAP(trace_dstate, CPU_TRACE_DSTATE_MAX_EVENTS); /* TODO Move common fields from CPUArchState here. */ diff --git a/trace/control-target.c b/trace/control-target.c index 99a8ed5157..31c2ed11a0 100644 --- a/trace/control-target.c +++ b/trace/control-target.c @@ -61,6 +61,13 @@ void trace_event_set_state_dynamic(TraceEvent *ev, bool state) } } +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); +} + void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, TraceEvent *ev, bool state) { @@ -73,13 +80,20 @@ void trace_event_set_vcpu_state_dynamic(CPUState *vcpu, if (state_pre != state) { if (state) { trace_events_enabled_count++; - set_bit(vcpu_id, vcpu->trace_dstate); + set_bit(vcpu_id, vcpu->trace_dstate_delayed); (*ev->dstate)++; } else { trace_events_enabled_count--; - clear_bit(vcpu_id, vcpu->trace_dstate); + clear_bit(vcpu_id, vcpu->trace_dstate_delayed); (*ev->dstate)--; } + /* + * 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); } }