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Tzvetomir StoyanovandArnaldo Carvalho de Melo
38847db974
Libtraceevent APIs for printing various trace events information are complicated, there are complex extra parameters. To control the way event information is printed, the user should call a set of functions in a specific sequence. These APIs are reimplemented to provide a more simple interface for printing event information. Removed APIs: tep_print_event_task() tep_print_event_time() tep_print_event_data() tep_event_info() tep_is_latency_format() tep_set_latency_format() tep_data_latency_format() tep_set_print_raw() A new API for printing event information is introduced: void tep_print_event(struct tep_handle *tep, struct trace_seq *s, struct tep_record *record, const char *fmt, ...); where "fmt" is a printf-like format string, followed by the event fields to be printed. Supported fields: TEP_PRINT_PID, "%d" - event PID TEP_PRINT_CPU, "%d" - event CPU TEP_PRINT_COMM, "%s" - event command string TEP_PRINT_NAME, "%s" - event name TEP_PRINT_LATENCY, "%s" - event latency TEP_PRINT_TIME, %d - event time stamp. A divisor and precision can be specified as part of this format string: "%precision.divisord". Example: "%3.1000d" - divide the time by 1000 and print the first 3 digits before the dot. Thus, the time stamp "123456000" will be printed as "123.456" TEP_PRINT_INFO, "%s" - event information. TEP_PRINT_INFO_RAW, "%s" - event information, in raw format. Example: tep_print_event(tep, s, record, "%16s-%-5d [%03d] %s %6.1000d %s %s", TEP_PRINT_COMM, TEP_PRINT_PID, TEP_PRINT_CPU, TEP_PRINT_LATENCY, TEP_PRINT_TIME, TEP_PRINT_NAME, TEP_PRINT_INFO); Output: ls-11314 [005] d.h. 185207.366383 function __wake_up Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: linux-trace-devel@vger.kernel.org Cc: Patrick McLean <chutzpah@gentoo.org> Link: http://lore.kernel.org/linux-trace-devel/20190801074959.22023-2-tz.stoyanov@gmail.com Link: http://lore.kernel.org/lkml/20190805204355.041132030@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.