trace/qmp.c

   1 /*
   2  * QMP commands for tracing events.
   3  *
   4  * Copyright (C) 2014-2016 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 "qapi/error.h"
  12 #include "qapi/qapi-commands-trace.h"
  13 #include "control.h"
  14
  15
  16 static bool check_events(bool ignore_unavailable, bool is_pattern,
  17                          const char *name, Error **errp)
  18 {
  19     if (!is_pattern) {
  20         TraceEvent *ev = trace_event_name(name);
  21
  22         /* error for non-existing event */
  23         if (ev == NULL) {
  24             error_setg(errp, "unknown event \"%s\"", name);
  25             return false;
  26         }
  27
  28         /* error for unavailable event */
  29         if (!ignore_unavailable && !trace_event_get_state_static(ev)) {
  30             error_setg(errp, "event \"%s\" is disabled", name);
  31             return false;
  32         }
  33
  34         return true;
  35     } else {
  36         /* error for unavailable events */
  37         TraceEventIter iter;
  38         TraceEvent *ev;
  39         trace_event_iter_init_pattern(&iter, name);
  40         while ((ev = trace_event_iter_next(&iter)) != NULL) {
  41             if (!ignore_unavailable && !trace_event_get_state_static(ev)) {
  42                 error_setg(errp, "event \"%s\" is disabled", trace_event_get_name(ev));
  43                 return false;
  44             }
  45         }
  46         return true;
  47     }
  48 }
  49
  50 TraceEventInfoList *qmp_trace_event_get_state(const char *name,
  51                                               bool has_vcpu, int64_t vcpu,
  52                                               Error **errp)
  53 {
  54     TraceEventInfoList *events = NULL;
  55     TraceEventIter iter;
  56     TraceEvent *ev;
  57     bool is_pattern = trace_event_is_pattern(name);
  58
  59     /* Check events */
  60     if (!check_events(true, is_pattern, name, errp)) {
  61         return NULL;
  62     }
  63
  64     /* Get states (all errors checked above) */
  65     trace_event_iter_init_pattern(&iter, name);
  66     while ((ev = trace_event_iter_next(&iter)) != NULL) {
  67         TraceEventInfo *value;
  68
  69         value = g_new(TraceEventInfo, 1);
  70         value->name = g_strdup(trace_event_get_name(ev));
  71
  72         if (!trace_event_get_state_static(ev)) {
  73             value->state = TRACE_EVENT_STATE_UNAVAILABLE;
  74         } else {
  75             if (trace_event_get_state_dynamic(ev)) {
  76                 value->state = TRACE_EVENT_STATE_ENABLED;
  77             } else {
  78                 value->state = TRACE_EVENT_STATE_DISABLED;
  79             }
  80         }
  81         QAPI_LIST_PREPEND(events, value);
  82     }
  83
  84     return events;
  85 }
  86
  87 void qmp_trace_event_set_state(const char *name, bool enable,
  88                                bool has_ignore_unavailable, bool ignore_unavailable,
  89                                bool has_vcpu, int64_t vcpu,
  90                                Error **errp)
  91 {
  92     TraceEventIter iter;
  93     TraceEvent *ev;
  94     bool is_pattern = trace_event_is_pattern(name);
  95
  96     /* Check events */
  97     if (!check_events(has_ignore_unavailable && ignore_unavailable,
  98                       is_pattern, name, errp)) {
  99         return;
 100     }
 101
 102     /* Apply changes (all errors checked above) */
 103     trace_event_iter_init_pattern(&iter, name);
 104     while ((ev = trace_event_iter_next(&iter)) != NULL) {
 105         if (!trace_event_get_state_static(ev)) {
 106             continue;
 107         }
 108         trace_event_set_state_dynamic(ev, enable);
 109     }
 110 }