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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.