From 10578a257d94fb59449d0b0e441990c45a036ccc Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 7 Jan 2016 16:55:26 +0300 Subject: trace: add "-trace enable=..." Allow enabling events without going through a file, for example: qemu-system-x86_64 -trace bdrv_aio_writev -trace bdrv_aio_readv or with globbing too: qemu-system-x86_64 -trace 'bdrv_aio_*' if an appropriate backend is enabled (simple, stderr, ftrace). Signed-off-by: Paolo Bonzini Signed-off-by: Denis V. Lunev Acked-by: Christian Borntraeger Message-id: 1452174932-28657-6-git-send-email-den@openvz.org Signed-off-by: Stefan Hajnoczi --- qemu-options.hx | 10 +++++++++- trace/control.c | 48 +++++++++++++++++++++++++++--------------------- trace/control.h | 9 +++++++++ vl.c | 11 +++++++++-- 4 files changed, 54 insertions(+), 24 deletions(-) diff --git a/qemu-options.hx b/qemu-options.hx index cbb4590ef7..35dc725958 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3544,7 +3544,7 @@ config files on @var{sysconfdir}, but won't make it skip the QEMU-provided confi files from @var{datadir}. ETEXI DEF("trace", HAS_ARG, QEMU_OPTION_trace, - "-trace [events=][,file=]\n" + "-trace [[enable=]][,events=][,file=]\n" " specify tracing options\n", QEMU_ARCH_ALL) STEXI @@ -3556,6 +3556,14 @@ HXCOMM HX does not support conditional compilation of text. Specify tracing options. @table @option +@item [enable=]@var{pattern} +Immediately enable events matching @var{pattern}. +The file must contain one event name (as listed in the @file{trace-events} file) +per line; globbing patterns are accepted too. This option is only +available if QEMU has been compiled with the @var{simple}, @var{stderr} +or @var{ftrace} tracing backend. To specify multiple events or patterns, +specify the @option{-trace} option multiple times. + @item events=@var{file} Immediately enable events listed in @var{file}. The file must contain one event name (as listed in the @file{trace-events} file) diff --git a/trace/control.c b/trace/control.c index f5a497a391..af92705bb4 100644 --- a/trace/control.c +++ b/trace/control.c @@ -88,6 +88,32 @@ TraceEvent *trace_event_pattern(const char *pat, TraceEvent *ev) return NULL; } +void trace_enable_events(const char *line_buf) +{ + const bool enable = ('-' != line_buf[0]); + const 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); + } + } +} + void trace_init_events(const char *fname) { Location loc; @@ -114,27 +140,7 @@ void trace_init_events(const char *fname) 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); - } - } + trace_enable_events(line_buf); } } if (fclose(fp) != 0) { diff --git a/trace/control.h b/trace/control.h index d50f3996c7..d5081ce169 100644 --- a/trace/control.h +++ b/trace/control.h @@ -181,6 +181,15 @@ void trace_init_events(const char *file); */ void trace_init_file(const char *file); +/** + * trace_enable_events: + * @line_buf: A string with a glob pattern of events to be enabled or, + * if the string starts with '-', disabled. + * + * Enable or disable matching events. + */ +void trace_enable_events(const char *line_buf); + #include "trace/control-internal.h" diff --git a/vl.c b/vl.c index 6370efee5f..58cc0507fe 100644 --- a/vl.c +++ b/vl.c @@ -270,9 +270,13 @@ static QemuOptsList qemu_sandbox_opts = { static QemuOptsList qemu_trace_opts = { .name = "trace", - .implied_opt_name = "trace", + .implied_opt_name = "enable", .head = QTAILQ_HEAD_INITIALIZER(qemu_trace_opts.head), .desc = { + { + .name = "enable", + .type = QEMU_OPT_STRING, + }, { .name = "events", .type = QEMU_OPT_STRING, @@ -3900,10 +3904,13 @@ int main(int argc, char **argv, char **envp) case QEMU_OPTION_trace: { opts = qemu_opts_parse_noisily(qemu_find_opts("trace"), - optarg, false); + optarg, true); if (!opts) { exit(1); } + if (qemu_opt_get(opts, "enable")) { + trace_enable_events(qemu_opt_get(opts, "enable")); + } trace_init_events(qemu_opt_get(opts, "events")); if (trace_file) { g_free(trace_file); -- cgit v1.2.3