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                                               Error **errp)
  52 {
  53     TraceEventInfoList *events = NULL;
  54     TraceEventIter iter;
  55     TraceEvent *ev;
  56     bool is_pattern = trace_event_is_pattern(name);
  57
  58     /* Check events */
  59     if (!check_events(true, is_pattern, name, errp)) {
  60         return NULL;
  61     }
  62
  63     /* Get states (all errors checked above) */
  64     trace_event_iter_init_pattern(&iter, name);
  65     while ((ev = trace_event_iter_next(&iter)) != NULL) {
  66         TraceEventInfo *value;
  67
  68         value = g_new(TraceEventInfo, 1);
  69         value->name = g_strdup(trace_event_get_name(ev));
  70
  71         if (!trace_event_get_state_static(ev)) {
  72             value->state = TRACE_EVENT_STATE_UNAVAILABLE;
  73         } else {
  74             if (trace_event_get_state_dynamic(ev)) {
  75                 value->state = TRACE_EVENT_STATE_ENABLED;
  76             } else {
  77                 value->state = TRACE_EVENT_STATE_DISABLED;
  78             }
  79         }
  80         QAPI_LIST_PREPEND(events, value);
  81     }
  82
  83     return events;
  84 }
  85
  86 void qmp_trace_event_set_state(const char *name, bool enable,
  87                                bool has_ignore_unavailable, bool ignore_unavailable,
  88                                Error **errp)
  89 {
  90     TraceEventIter iter;
  91     TraceEvent *ev;
  92     bool is_pattern = trace_event_is_pattern(name);
  93
  94     /* Check events */
  95     if (!check_events(has_ignore_unavailable && ignore_unavailable,
  96                       is_pattern, name, errp)) {
  97         return;
  98     }
  99
 100     /* Apply changes (all errors checked above) */
 101     trace_event_iter_init_pattern(&iter, name);
 102     while ((ev = trace_event_iter_next(&iter)) != NULL) {
 103         if (!trace_event_get_state_static(ev)) {
 104             continue;
 105         }
 106         trace_event_set_state_dynamic(ev, enable);
 107     }
 108 }