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 --- trace/control.c | 48 +++++++++++++++++++++++++++--------------------- trace/control.h | 9 +++++++++ 2 files changed, 36 insertions(+), 21 deletions(-) (limited to 'trace') 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" -- cgit v1.2.1