tep_get_page_size(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | EXAMPLE | FILES | SEE ALSO | AUTHOR | REPORTING BUGS | LICENSE | RESOURCES | NOTES | COLOPHON

LIBTRACEEVENT(3)          libtraceevent Manual          LIBTRACEEVENT(3)

NAME         top

       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         top

       #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         top

       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         top

       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         top

           #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         top

           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         top

       libtraceevent(3), trace-cmd(1)

AUTHOR         top

           Steven Rostedt <[email protected][1]>, author of libtraceevent.
           Tzvetomir Stoyanov <[email protected][2]>, author of this man page.

REPORTING BUGS         top

       Report bugs to <[email protected][3]>

LICENSE         top

       libtraceevent is Free Software licensed under the GNU LGPL 2.1

RESOURCES         top

       https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/ 

NOTES         top

        1. [email protected]
           mailto:[email protected]

        2. [email protected]
           mailto:[email protected]

        3. [email protected]
           mailto:[email protected]

COLOPHON         top

       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,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to [email protected]

libtraceevent 1.8.2            06/07/2024               LIBTRACEEVENT(3)