| Message ID | 20190412133811.15878-5-tstoyanov@vmware.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Libtraceevent MAN pages | expand |
On Fri, 12 Apr 2019 16:37:45 +0300 Tzvetomir Stoyanov <tstoyanov@vmware.com> wrote: > Create a man page for libtraceevent APIs: > tep_get_header_page_size(), > tep_get_header_timestamp_size(), > tep_is_old_format() > > Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> > --- > .../libtraceevent-header_page.txt | 105 ++++++++++++++++++ > 1 file changed, 105 insertions(+) > create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-header_page.txt > > diff --git a/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt b/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt > new file mode 100644 > index 000000000000..e1bd664ac123 > --- /dev/null > +++ b/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt > @@ -0,0 +1,105 @@ > +libtraceevent(3) > +================ > + > +NAME > +---- > +tep_get_header_page_size, tep_get_header_timestamp_size, tep_is_old_format - > +Get the data stored in the header page, in kernel context. > + > +SYNOPSIS > +-------- > +[verse] > +-- > +*#include <event-parse.h>* > + > +int *tep_get_header_page_size*(struct tep_handle pass:[*]_tep_); > +int *tep_get_header_timestamp_size*(struct tep_handle pass:[*]_tep_); > +bool *tep_is_old_format*(struct tep_handle pass:[*]_tep_); > +-- > +DESCRIPTION > +----------- > +These functions retrieve information from kernel context, stored in > +/sys/kernel/debug/tracing/events/header_page. Old kernels do not have header Let's avoid using full path names. This should be: stored in the tracefs events/header_page. > +page info, so default values from user space context are used. > + > +The _tep_get_header_page_size()_ function returns the size of a long integer, > +in kernel context. The _tep_ argument is trace event parser context. > +This information is retrieved from /sys/kernel/debug/tracing/events/header_page, Same here. > + "commit" field. > + > +The _tep_get_header_timestamp_size()_ function returns the size of timestamps, > +in kernel context. The _tep_ argument is trace event parser context. > +This information is retrieved from /sys/kernel/debug/tracing/events/header_page, and here. > + "timestamp" field. > + > +The _tep_is_old_format()_ function returns if the kernel is old one and has no The _tep_is_old_format()_ function returns true if the kernel predates the addition of events/header_page, otherwise it returns false. > +/sys/kernel/debug/tracing/events/header_page. > + > +RETURN VALUE > +------------ > +The _tep_get_header_page_size()_ function returns the size of a long integer, > +in bytes. > + > +The _tep_get_header_timestamp_size()_ function returns the size of timestamps, > +in bytes. > + > +The _tep_is_old_format()_ function returns true, if an old kernel is used to > +generate the tracing data, which has no > +/sys/kernel/debug/tracing/events/header_page. If the kernel is new, or _tep_ is Just say "no event/header_page" -- Steve > +NULL, false is returned. > + > +EXAMPLE > +------- > +[source,c] > +-- > +#include <event-parse.h> > +... > +struct tep_handle *tep = tep_alloc(); > +... > + int longsize; > + int timesize; > + bool old; > + > + longsize = tep_get_header_page_size(tep); > + timesize = tep_get_header_timestamp_size(tep); > + old = tep_is_old_format(tep); > + > + printf ("%s kernel is used to generate the tracing data.\n", > + old?"Old":"New"); > + printf("The size of a long integer is %d bytes.\n", longsize); > + printf("The timestamps size is %d bytes.\n", timesize); > +... > +-- > + > +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
diff --git a/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt b/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt new file mode 100644 index 000000000000..e1bd664ac123 --- /dev/null +++ b/tools/lib/traceevent/Documentation/libtraceevent-header_page.txt @@ -0,0 +1,105 @@ +libtraceevent(3) +================ + +NAME +---- +tep_get_header_page_size, tep_get_header_timestamp_size, tep_is_old_format - +Get the data stored in the header page, in kernel context. + +SYNOPSIS +-------- +[verse] +-- +*#include <event-parse.h>* + +int *tep_get_header_page_size*(struct tep_handle pass:[*]_tep_); +int *tep_get_header_timestamp_size*(struct tep_handle pass:[*]_tep_); +bool *tep_is_old_format*(struct tep_handle pass:[*]_tep_); +-- +DESCRIPTION +----------- +These functions retrieve information from kernel context, stored in +/sys/kernel/debug/tracing/events/header_page. Old kernels do not have header +page info, so default values from user space context are used. + +The _tep_get_header_page_size()_ function returns the size of a long integer, +in kernel context. The _tep_ argument is trace event parser context. +This information is retrieved from /sys/kernel/debug/tracing/events/header_page, + "commit" field. + +The _tep_get_header_timestamp_size()_ function returns the size of timestamps, +in kernel context. The _tep_ argument is trace event parser context. +This information is retrieved from /sys/kernel/debug/tracing/events/header_page, + "timestamp" field. + +The _tep_is_old_format()_ function returns if the kernel is old one and has no +/sys/kernel/debug/tracing/events/header_page. + +RETURN VALUE +------------ +The _tep_get_header_page_size()_ function returns the size of a long integer, +in bytes. + +The _tep_get_header_timestamp_size()_ function returns the size of timestamps, +in bytes. + +The _tep_is_old_format()_ function returns true, if an old kernel is used to +generate the tracing data, which has no +/sys/kernel/debug/tracing/events/header_page. If the kernel is new, or _tep_ is +NULL, false is returned. + +EXAMPLE +------- +[source,c] +-- +#include <event-parse.h> +... +struct tep_handle *tep = tep_alloc(); +... + int longsize; + int timesize; + bool old; + + longsize = tep_get_header_page_size(tep); + timesize = tep_get_header_timestamp_size(tep); + old = tep_is_old_format(tep); + + printf ("%s kernel is used to generate the tracing data.\n", + old?"Old":"New"); + printf("The size of a long integer is %d bytes.\n", longsize); + printf("The timestamps size is %d bytes.\n", timesize); +... +-- + +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
Create a man page for libtraceevent APIs: tep_get_header_page_size(), tep_get_header_timestamp_size(), tep_is_old_format() Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> --- .../libtraceevent-header_page.txt | 105 ++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-header_page.txt