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From: Tzvetomir Stoyanov <tstoyanov@vmware.com>
To: "rostedt@goodmis.org" <rostedt@goodmis.org>
Cc: "linux-trace-devel@vger.kernel.org" <linux-trace-devel@vger.kernel.org>
Subject: [PATCH 5/7] tools/lib/traceevent: Implement libtraceevent man pages
Date: Tue, 6 Nov 2018 13:20:54 +0000	[thread overview]
Message-ID: <20181106132035.7692-6-tstoyanov@vmware.com> (raw)
In-Reply-To: <20181106132035.7692-1-tstoyanov@vmware.com>

This patch implements a man page, which documents
tep_is_latency_format() and tep_set_latency_format()
libtraceevent APIs

Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
---
 .../libtraceevent-latency_format.txt          | 98 +++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-latency_format.txt

diff --git a/tools/lib/traceevent/Documentation/libtraceevent-latency_format.txt b/tools/lib/traceevent/Documentation/libtraceevent-latency_format.txt
new file mode 100644
index 000000000000..a7eaed5d1a7e
--- /dev/null
+++ b/tools/lib/traceevent/Documentation/libtraceevent-latency_format.txt
@@ -0,0 +1,98 @@
+libtraceevent(3)
+================
+
+NAME
+----
+tep_set_latency_format,tep_is_latency_format - Get / set "latency output" format.
+
+SYNOPSIS
+--------
+[verse]
+--
+*#include <event-parse.h>*
+
+void *tep_set_latency_format*(struct tep_handle pass:[*]_tep_, int _lat_);
+int *tep_is_latency_format*(struct tep_handle pass:[*]_tep_);
+
+--
+
+DESCRIPTION
+-----------
+"Latency output" format prints information about interrupts being disabled, 
+soft irq being disabled, the "need_resched" flag being set, preempt count, 
+and big kernel lock. This information is recorded with every event, but by 
+default is not printed.
+
+The _tep_set_latency_format()_ function enables the "latency output" printing.
+The _tep_ argument is trace event parser context. The _lat_ argument can be zero,
+for "latency output" disabled, or non zero for "latency output" enabled.
+Information is displayed with 6 characters. When a field is zero, or N/A, a pass:['.'] 
+is printed. Example:
+[verse]
+--
+  <idle>-0       0d.h1. 106467.859747: function:             ktime_get <-- tick_check_idle
+--
+The 0d.h1. denotes this information. The first character is never a pass:['.']
+and represents what CPU the trace was recorded on (CPU 0). The pass:['d'] denotes
+that interrupts were disabled. The pass:['h'] means that this was called inside
+an interrupt handler. The pass:['1'] is the preemption disabled (preempt_count)
+was set to one.  The two pass:['.']s are "need_resched" flag and kernel lock
+counter. If the "need_resched" flag is set, then that character would be a pass:['N'].
+
+The _tep_is_latency_format()_ function returns if "latency output" is enabled.
+
+RETURN VALUE
+------------
+
+The _tep_is_latency_format()_ function returns non zero if "latency output" 
+is enabled, or zero if it is disabled.
+
+EXAMPLE
+-------
+[source,c]
+--
+#include <event-parse.h>
+...
+struct tep_handle *tep = tep_alloc();
+...
+	tep_set_latency_format(tep, 1);
+...
+	if (tep_is_latency_format(tep)) {
+		/* latency output format is enabled */
+	} else {
+		/* latency output format is disabled */
+	}
+--
+
+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
-- 
2.17.2

  parent reply	other threads:[~2018-11-06 22:46 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-06 13:20 [PATCH 0/7] libtracevent man pages Tzvetomir Stoyanov
2018-11-06 13:20 ` [PATCH 1/7] tools/lib/traceevent: Implement libtraceevent " Tzvetomir Stoyanov
2018-11-06 13:20 ` [PATCH 2/7] " Tzvetomir Stoyanov
2018-11-07  0:07   ` Steven Rostedt
2018-11-06 13:20 ` [PATCH 3/7] " Tzvetomir Stoyanov
2018-11-07  0:14   ` Steven Rostedt
2018-11-06 13:20 ` [PATCH 4/7] " Tzvetomir Stoyanov
2018-11-07  0:15   ` Steven Rostedt
2018-11-07 14:45     ` Tzvetomir Stoyanov
2018-11-06 13:20 ` Tzvetomir Stoyanov [this message]
2018-11-07  0:19   ` [PATCH 5/7] " Steven Rostedt
2018-11-06 13:20 ` [PATCH 6/7] " Tzvetomir Stoyanov
2018-11-07  0:23   ` Steven Rostedt
2018-11-06 13:20 ` [PATCH 7/7] " Tzvetomir Stoyanov

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