Commit 585ec727 authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Stefan Hajnoczi
Browse files

trace: track enabled events in a separate array 



This is more cache friendly on the fast path, where we already have
the event id available.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 43b48cfc

scripts/tracetool/format/events_c.py

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ def generate(events, backend): 
    out('TraceEvent trace_events[TRACE_EVENT_COUNT] = {')



    for e in events:

        out('    { .id = %(id)s, .name = \"%(name)s\", .sstate = %(sstate)s, .dstate = 0 },',

        out('    { .id = %(id)s, .name = \"%(name)s\", .sstate = %(sstate)s },',

            id = "TRACE_" + e.name.upper(),

            name = e.name,

            sstate = "TRACE_%s_ENABLED" % e.name.upper())

trace/control-internal.h

+11 −4
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 




extern TraceEvent trace_events[];

extern bool trace_events_dstate[];

extern int trace_events_enabled_count;
@@ -52,18 +53,24 @@ static inline bool trace_event_get_state_static(TraceEvent *ev) 
    return ev->sstate;

}



static inline bool trace_event_get_state_dynamic_by_id(int id)

{

    return unlikely(trace_events_enabled_count) && trace_events_dstate[id];

}



static inline bool trace_event_get_state_dynamic(TraceEvent *ev)

{

    assert(ev != NULL);

    return unlikely(trace_events_enabled_count) && ev->dstate;

    int id = trace_event_get_id(ev);

    return trace_event_get_state_dynamic_by_id(id);

}



static inline void trace_event_set_state_dynamic(TraceEvent *ev, bool state)

{

    int id = trace_event_get_id(ev);

    assert(ev != NULL);

    assert(trace_event_get_state_static(ev));

    trace_events_enabled_count += state - ev->dstate;

    ev->dstate = state;

    trace_events_enabled_count += state - trace_events_dstate[id];

    trace_events_dstate[id] = state;

}



#endif  /* TRACE__CONTROL_INTERNAL_H */

trace/control.c

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include "qemu/error-report.h"



int trace_events_enabled_count;

bool trace_events_dstate[TRACE_EVENT_COUNT];



TraceEvent *trace_event_name(const char *name)

{

trace/control.h

+1 −1
Original line number Diff line number Diff line
@@ -104,7 +104,7 @@ static const char * trace_event_get_name(TraceEvent *ev); 
 * As a down side, you must always use an immediate #TraceEventID value.

 */

#define trace_event_get_state(id)                       \

    ((id ##_ENABLED) && trace_event_get_state_dynamic(trace_event_id(id)))

    ((id ##_ENABLED) && trace_event_get_state_dynamic_by_id(id))



/**

 * trace_event_get_state_static:

trace/event-internal.h

+0 −2
Original line number Diff line number Diff line
@@ -18,7 +18,6 @@ 
 * @id: Unique event identifier.

 * @name: Event name.

 * @sstate: Static tracing state.

 * @dstate: Dynamic tracing state.

 *

 * Opaque generic description of a tracing event.

 */
@@ -26,7 +25,6 @@ typedef struct TraceEvent { 
    TraceEventID id;

    const char * name;

    const bool sstate;

    bool dstate;

} TraceEvent;