diff options
Diffstat (limited to 'qemu/trace/control.c')
| -rw-r--r-- | qemu/trace/control.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/qemu/trace/control.c b/qemu/trace/control.c new file mode 100644 index 000000000..995beb384 --- /dev/null +++ b/qemu/trace/control.c @@ -0,0 +1,169 @@ +/* + * Interface for configuring and controlling the state of tracing events. + * + * Copyright (C) 2011-2014 Lluís Vilanova <vilanova@ac.upc.edu> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "trace/control.h" +#ifdef CONFIG_TRACE_SIMPLE +#include "trace/simple.h" +#endif +#ifdef CONFIG_TRACE_FTRACE +#include "trace/ftrace.h" +#endif +#include "qemu/error-report.h" + +TraceEvent *trace_event_name(const char *name) +{ + assert(name != NULL); + + TraceEventID i; + for (i = 0; i < trace_event_count(); i++) { + TraceEvent *ev = trace_event_id(i); + if (strcmp(trace_event_get_name(ev), name) == 0) { + return ev; + } + } + return NULL; +} + +static bool pattern_glob(const char *pat, const char *ev) +{ + while (*pat != '\0' && *ev != '\0') { + if (*pat == *ev) { + pat++; + ev++; + } + else if (*pat == '*') { + if (pattern_glob(pat, ev+1)) { + return true; + } else if (pattern_glob(pat+1, ev)) { + return true; + } else { + return false; + } + } else { + return false; + } + } + + while (*pat == '*') { + pat++; + } + + if (*pat == '\0' && *ev == '\0') { + return true; + } else { + return false; + } +} + +TraceEvent *trace_event_pattern(const char *pat, TraceEvent *ev) +{ + assert(pat != NULL); + + TraceEventID i; + + if (ev == NULL) { + i = -1; + } else { + i = trace_event_get_id(ev); + } + i++; + + while (i < trace_event_count()) { + TraceEvent *res = trace_event_id(i); + if (pattern_glob(pat, trace_event_get_name(res))) { + return res; + } + i++; + } + + return NULL; +} + +static void trace_init_events(const char *fname) +{ + Location loc; + FILE *fp; + char line_buf[1024]; + size_t line_idx = 0; + + if (fname == NULL) { + return; + } + + loc_push_none(&loc); + loc_set_file(fname, 0); + fp = fopen(fname, "r"); + if (!fp) { + error_report("%s", strerror(errno)); + exit(1); + } + while (fgets(line_buf, sizeof(line_buf), fp)) { + loc_set_file(fname, ++line_idx); + size_t len = strlen(line_buf); + if (len > 1) { /* skip empty lines */ + line_buf[len - 1] = '\0'; + if ('#' == line_buf[0]) { /* skip commented lines */ + continue; + } + const bool enable = ('-' != line_buf[0]); + char *line_ptr = enable ? line_buf : line_buf + 1; + if (trace_event_is_pattern(line_ptr)) { + TraceEvent *ev = NULL; + while ((ev = trace_event_pattern(line_ptr, ev)) != NULL) { + if (trace_event_get_state_static(ev)) { + trace_event_set_state_dynamic(ev, enable); + } + } + } else { + TraceEvent *ev = trace_event_name(line_ptr); + if (ev == NULL) { + error_report("WARNING: trace event '%s' does not exist", + line_ptr); + } else if (!trace_event_get_state_static(ev)) { + error_report("WARNING: trace event '%s' is not traceable", + line_ptr); + } else { + trace_event_set_state_dynamic(ev, enable); + } + } + } + } + if (fclose(fp) != 0) { + loc_set_file(fname, 0); + error_report("%s", strerror(errno)); + exit(1); + } + loc_pop(&loc); +} + +bool trace_init_backends(const char *events, const char *file) +{ +#ifdef CONFIG_TRACE_SIMPLE + if (!st_init(file)) { + fprintf(stderr, "failed to initialize simple tracing backend.\n"); + return false; + } +#else + if (file) { + fprintf(stderr, "error: -trace file=...: " + "option not supported by the selected tracing backends\n"); + return false; + } +#endif + +#ifdef CONFIG_TRACE_FTRACE + if (!ftrace_init()) { + fprintf(stderr, "failed to initialize ftrace backend.\n"); + return false; + } +#endif + + trace_init_events(events); + return true; +} |