mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
tools lib traceevent: Man pages for APIs used to extract common fields from a record
Create man pages for libtraceevent APIs: tep_data_type(), tep_data_pid(), tep_data_preempt_count(), tep_data_flags() 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 Link: http://lore.kernel.org/linux-trace-devel/20190503091119.23399-26-tstoyanov@vmware.com Link: http://lkml.kernel.org/r/20190510200110.284281830@goodmis.org [ Fixed missing T in description of NOSUPPORT flag ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
parent
73b6b470f6
commit
0133fc6068
1 changed files with 137 additions and 0 deletions
|
@ -0,0 +1,137 @@
|
|||
libtraceevent(3)
|
||||
================
|
||||
|
||||
NAME
|
||||
----
|
||||
tep_data_type, tep_data_pid,tep_data_preempt_count, tep_data_flags -
|
||||
Extract common fields from a record.
|
||||
|
||||
SYNOPSIS
|
||||
--------
|
||||
[verse]
|
||||
--
|
||||
*#include <event-parse.h>*
|
||||
|
||||
enum *trace_flag_type* {
|
||||
_TRACE_FLAG_IRQS_OFF_,
|
||||
_TRACE_FLAG_IRQS_NOSUPPORT_,
|
||||
_TRACE_FLAG_NEED_RESCHED_,
|
||||
_TRACE_FLAG_HARDIRQ_,
|
||||
_TRACE_FLAG_SOFTIRQ_,
|
||||
};
|
||||
|
||||
int *tep_data_type*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_);
|
||||
int *tep_data_pid*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_);
|
||||
int *tep_data_preempt_count*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_);
|
||||
int *tep_data_flags*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_);
|
||||
--
|
||||
|
||||
DESCRIPTION
|
||||
-----------
|
||||
This set of functions can be used to extract common fields from a record.
|
||||
|
||||
The _tep_data_type()_ function gets the event id from the record _rec_.
|
||||
It reads the "common_type" field. The _tep_ argument is the trace event parser
|
||||
context.
|
||||
|
||||
The _tep_data_pid()_ function gets the process id from the record _rec_.
|
||||
It reads the "common_pid" field. The _tep_ argument is the trace event parser
|
||||
context.
|
||||
|
||||
The _tep_data_preempt_count()_ function gets the preemption count from the
|
||||
record _rec_. It reads the "common_preempt_count" field. The _tep_ argument is
|
||||
the trace event parser context.
|
||||
|
||||
The _tep_data_flags()_ function gets the latency flags from the record _rec_.
|
||||
It reads the "common_flags" field. The _tep_ argument is the trace event parser
|
||||
context. Supported latency flags are:
|
||||
[verse]
|
||||
--
|
||||
_TRACE_FLAG_IRQS_OFF_, Interrupts are disabled.
|
||||
_TRACE_FLAG_IRQS_NOSUPPORT_, Reading IRQ flag is not supported by the architecture.
|
||||
_TRACE_FLAG_NEED_RESCHED_, Task needs rescheduling.
|
||||
_TRACE_FLAG_HARDIRQ_, Hard IRQ is running.
|
||||
_TRACE_FLAG_SOFTIRQ_, Soft IRQ is running.
|
||||
--
|
||||
|
||||
RETURN VALUE
|
||||
------------
|
||||
The _tep_data_type()_ function returns an integer, representing the event id.
|
||||
|
||||
The _tep_data_pid()_ function returns an integer, representing the process id
|
||||
|
||||
The _tep_data_preempt_count()_ function returns an integer, representing the
|
||||
preemption count.
|
||||
|
||||
The _tep_data_flags()_ function returns an integer, representing the latency
|
||||
flags. Look at the _trace_flag_type_ enum for supported flags.
|
||||
|
||||
All these functions in case of an error return a negative integer.
|
||||
|
||||
EXAMPLE
|
||||
-------
|
||||
[source,c]
|
||||
--
|
||||
#include <event-parse.h>
|
||||
...
|
||||
struct tep_handle *tep = tep_alloc();
|
||||
...
|
||||
void process_record(struct tep_record *record)
|
||||
{
|
||||
int data;
|
||||
|
||||
data = tep_data_type(tep, record);
|
||||
if (data >= 0) {
|
||||
/* Got the ID of the event */
|
||||
}
|
||||
|
||||
data = tep_data_pid(tep, record);
|
||||
if (data >= 0) {
|
||||
/* Got the process ID */
|
||||
}
|
||||
|
||||
data = tep_data_preempt_count(tep, record);
|
||||
if (data >= 0) {
|
||||
/* Got the preemption count */
|
||||
}
|
||||
|
||||
data = tep_data_flags(tep, record);
|
||||
if (data >= 0) {
|
||||
/* Got the latency flags */
|
||||
}
|
||||
}
|
||||
...
|
||||
--
|
||||
|
||||
FILES
|
||||
-----
|
||||
[verse]
|
||||
--
|
||||
*event-parse.h*
|
||||
Header file to include in order to have access to the library APIs.
|
||||
*-ltraceevent*
|
||||
Linker switch to add when building a program that uses the library.
|
||||
--
|
||||
|
||||
SEE ALSO
|
||||
--------
|
||||
_libtraceevent(3)_, _trace-cmd(1)_
|
||||
|
||||
AUTHOR
|
||||
------
|
||||
[verse]
|
||||
--
|
||||
*Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceevent*.
|
||||
*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>, author of this man page.
|
||||
--
|
||||
REPORTING BUGS
|
||||
--------------
|
||||
Report bugs to <linux-trace-devel@vger.kernel.org>
|
||||
|
||||
LICENSE
|
||||
-------
|
||||
libtraceevent is Free Software licensed under the GNU LGPL 2.1
|
||||
|
||||
RESOURCES
|
||||
---------
|
||||
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
|
Loading…
Reference in a new issue