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Message-ID: <20200702185703.619656282@goodmis.org>
Date: Thu, 02 Jul 2020 14:53:45 -0400
From: Steven Rostedt <rostedt@...dmis.org>
To: linux-kernel@...r.kernel.org, linux-trace-devel@...r.kernel.org
Cc: Arnaldo Carvalho de Melo <acme@...nel.org>,
Ingo Molnar <mingo@...nel.org>, Jiri Olsa <jolsa@...hat.com>,
Namhyung Kim <namhyung@...nel.org>,
Andrew Morton <akpm@...ux-foundation.org>,
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@...il.com>
Subject: [PATCH v2 01/15] tools lib traceevent: Add API to read time information from kbuffer
From: "Steven Rostedt (Red Hat)" <rostedt@...dmis.org>
Add the functions kbuffer_subbuf_timestamp() and kbuffer_ptr_delta() to get
the timing data stored in the ring buffer that is used to produced the time
stamps of the records.
This is useful for tools like trace-cmd to be able to display the content of
the read data to understand why the records show the time stamps that they
do.
Link: http://lore.kernel.org/linux-trace-devel/20200625100516.365338-2-tz.stoyanov@gmail.com
Signed-off-by: Steven Rostedt <rostedt@...dmis.org>
[ Ported from trace-cmd.git ]
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@...il.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@...dmis.org>
---
tools/lib/traceevent/kbuffer-parse.c | 28 ++++++++++++++++++++++++++++
tools/lib/traceevent/kbuffer.h | 2 ++
2 files changed, 30 insertions(+)
diff --git a/tools/lib/traceevent/kbuffer-parse.c b/tools/lib/traceevent/kbuffer-parse.c
index 27f3b07fdae8..583db99aee94 100644
--- a/tools/lib/traceevent/kbuffer-parse.c
+++ b/tools/lib/traceevent/kbuffer-parse.c
@@ -546,6 +546,34 @@ int kbuffer_load_subbuffer(struct kbuffer *kbuf, void *subbuffer)
return 0;
}
+/**
+ * kbuffer_subbuf_timestamp - read the timestamp from a sub buffer
+ * @kbuf: The kbuffer to load
+ * @subbuf: The subbuffer to read from.
+ *
+ * Return the timestamp from a subbuffer.
+ */
+unsigned long long kbuffer_subbuf_timestamp(struct kbuffer *kbuf, void *subbuf)
+{
+ return kbuf->read_8(subbuf);
+}
+
+/**
+ * kbuffer_ptr_delta - read the delta field from a record
+ * @kbuf: The kbuffer to load
+ * @ptr: The record in the buffe.
+ *
+ * Return the timestamp delta from a record
+ */
+unsigned int kbuffer_ptr_delta(struct kbuffer *kbuf, void *ptr)
+{
+ unsigned int type_len_ts;
+
+ type_len_ts = read_4(kbuf, ptr);
+ return ts4host(kbuf, type_len_ts);
+}
+
+
/**
* kbuffer_read_event - read the next event in the kbuffer subbuffer
* @kbuf: The kbuffer to read from
diff --git a/tools/lib/traceevent/kbuffer.h b/tools/lib/traceevent/kbuffer.h
index ed4d697fc137..5fa8292e341b 100644
--- a/tools/lib/traceevent/kbuffer.h
+++ b/tools/lib/traceevent/kbuffer.h
@@ -49,6 +49,8 @@ int kbuffer_load_subbuffer(struct kbuffer *kbuf, void *subbuffer);
void *kbuffer_read_event(struct kbuffer *kbuf, unsigned long long *ts);
void *kbuffer_next_event(struct kbuffer *kbuf, unsigned long long *ts);
unsigned long long kbuffer_timestamp(struct kbuffer *kbuf);
+unsigned long long kbuffer_subbuf_timestamp(struct kbuffer *kbuf, void *subbuf);
+unsigned int kbuffer_ptr_delta(struct kbuffer *kbuf, void *ptr);
void *kbuffer_translate_data(int swap, void *data, unsigned int *size);
--
2.26.2
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