tep_get_page_size(3) — Linux manual page
LIBTRACEEVENT(3) libtraceevent Manual LIBTRACEEVENT(3)
NAME
tep_get_page_size, tep_set_page_size,
tep_get_sub_buffer_data_size, tep_get_sub_buffer_size - Get / set
the size of a memory page on the machine, where the trace is
generated
SYNOPSIS
#include <event-parse.h>
int tep_get_page_size(struct tep_handle *tep);
void tep_set_page_size(struct tep_handle *tep, int page_size);
int tep_get_sub_buffer_size(struct tep_handle *tep);
int tep_get_sub_buffer_data_size(struct tep_handle *tep);
int tep_get_sub_buffer_commit_offset(struct tep_handle *tep);
DESCRIPTION
The tep_get_page_size() function returns the size of a memory
page on the machine, where the trace is generated. The tep
argument is trace event parser context.
The tep_set_page_size() function stores in the tep context the
size of a memory page on the machine, where the trace is
generated. The tep argument is trace event parser context. The
page_size argument is the size of a memory page, in bytes.
The tep_get_sub_buffer_size() returns the size of each "sub
buffer" of the ring buffer. The Linux kernel ring buffer is
broken up into sections called sub buffers. This returns the size
of those buffers.
The tep_get_sub_buffer_data_size() returns the size of just the
data portion of the sub buffers.
The tep_get_sub_buffer_commit_offset() returns the offset on the
sub buffer that holds the committed portion of data. This number
contains the index from the data portion of the sub buffer that
is the end of the last element on the sub buffer.
RETURN VALUE
The tep_get_page_size() function returns size of the memory page,
in bytes.
The tep_get_sub_buffer_size() function returns the number of
bytes each sub buffer is made up of.
The tep_get_sub_buffer_commit_offset() function returns the
location on the sub buffer that contains the index of the last
element.
EXAMPLE
#include <unistd.h>
#include <event-parse.h>
...
struct tep_handle *tep = tep_alloc();
...
int page_size = getpagesize();
tep_set_page_size(tep, page_size);
printf("The page size for this machine is %d\n", tep_get_page_size(tep));
FILES
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
Steven Rostedt <rostedt@goodmis.org[1]>, author of libtraceevent.
Tzvetomir Stoyanov <tz.stoyanov@gmail.com[2]>, author of this man page.
REPORTING BUGS
Report bugs to <linux-trace-devel@vger.kernel.org[3]>
LICENSE
libtraceevent is Free Software licensed under the GNU LGPL 2.1
RESOURCES
https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/
NOTES
1. rostedt@goodmis.org
mailto:rostedt@goodmis.org
2. tz.stoyanov@gmail.com
mailto:tz.stoyanov@gmail.com
3. linux-trace-devel@vger.kernel.org
mailto:linux-trace-devel@vger.kernel.org
COLOPHON
This page is part of the libtraceevent (Linux kernel trace event
library) project. Information about the project can be found at
⟨https://www.trace-cmd.org/⟩. If you have a bug report for this
manual page, see ⟨https://www.trace-cmd.org/⟩. This page was
obtained from the project's upstream Git repository
⟨https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git⟩
on 2024-06-14. (At that time, the date of the most recent commit
that was found in the repository was 2024-05-17.) If you
discover any rendering problems in this HTML version of the page,
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