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Diffstat (limited to 'tools/lib/traceevent/Documentation/libtraceevent-commands.txt')
-rw-r--r-- | tools/lib/traceevent/Documentation/libtraceevent-commands.txt | 153 |
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diff --git a/tools/lib/traceevent/Documentation/libtraceevent-commands.txt b/tools/lib/traceevent/Documentation/libtraceevent-commands.txt deleted file mode 100644 index bec552001f8e..000000000000 --- a/tools/lib/traceevent/Documentation/libtraceevent-commands.txt +++ /dev/null @@ -1,153 +0,0 @@ -libtraceevent(3) -================ - -NAME ----- -tep_register_comm, tep_override_comm, tep_pid_is_registered, -tep_data_comm_from_pid, tep_data_pid_from_comm, tep_cmdline_pid - -Manage pid to process name mappings. - -SYNOPSIS --------- -[verse] --- -*#include <event-parse.h>* - -int *tep_register_comm*(struct tep_handle pass:[*]_tep_, const char pass:[*]_comm_, int _pid_); -int *tep_override_comm*(struct tep_handle pass:[*]_tep_, const char pass:[*]_comm_, int _pid_); -bool *tep_is_pid_registered*(struct tep_handle pass:[*]_tep_, int _pid_); -const char pass:[*]*tep_data_comm_from_pid*(struct tep_handle pass:[*]_pevent_, int _pid_); -struct cmdline pass:[*]*tep_data_pid_from_comm*(struct tep_handle pass:[*]_pevent_, const char pass:[*]_comm_, struct cmdline pass:[*]_next_); -int *tep_cmdline_pid*(struct tep_handle pass:[*]_pevent_, struct cmdline pass:[*]_cmdline_); --- - -DESCRIPTION ------------ -These functions can be used to handle the mapping between pid and process name. -The library builds a cache of these mappings, which is used to display the name -of the process, instead of its pid. This information can be retrieved from -tracefs/saved_cmdlines file. - -The _tep_register_comm()_ function registers a _pid_ / process name mapping. -If a command with the same _pid_ is already registered, an error is returned. -The _pid_ argument is the process ID, the _comm_ argument is the process name, -_tep_ is the event context. The _comm_ is duplicated internally. - -The _tep_override_comm()_ function registers a _pid_ / process name mapping. -If a process with the same pid is already registered, the process name string is -udapted with the new one. The _pid_ argument is the process ID, the _comm_ -argument is the process name, _tep_ is the event context. The _comm_ is -duplicated internally. - -The _tep_is_pid_registered()_ function checks if a pid has a process name -mapping registered. The _pid_ argument is the process ID, _tep_ is the event -context. - -The _tep_data_comm_from_pid()_ function returns the process name for a given -pid. The _pid_ argument is the process ID, _tep_ is the event context. -The returned string should not be freed, but will be freed when the _tep_ -handler is closed. - -The _tep_data_pid_from_comm()_ function returns a pid for a given process name. -The _comm_ argument is the process name, _tep_ is the event context. -The argument _next_ is the cmdline structure to search for the next pid. -As there may be more than one pid for a given process, the result of this call -can be passed back into a recurring call in the _next_ parameter, to search for -the next pid. If _next_ is NULL, it will return the first pid associated with -the _comm_. The function performs a linear search, so it may be slow. - -The _tep_cmdline_pid()_ function returns the pid associated with a given -_cmdline_. The _tep_ argument is the event context. - -RETURN VALUE ------------- -_tep_register_comm()_ function returns 0 on success. In case of an error -1 is -returned and errno is set to indicate the cause of the problem: ENOMEM, if there -is not enough memory to duplicate the _comm_ or EEXIST if a mapping for this -_pid_ is already registered. - -_tep_override_comm()_ function returns 0 on success. In case of an error -1 is -returned and errno is set to indicate the cause of the problem: ENOMEM, if there -is not enough memory to duplicate the _comm_. - -_tep_is_pid_registered()_ function returns true if the _pid_ has a process name -mapped to it, false otherwise. - -_tep_data_comm_from_pid()_ function returns the process name as string, or the -string "<...>" if there is no mapping for the given pid. - -_tep_data_pid_from_comm()_ function returns a pointer to a struct cmdline, that -holds a pid for a given process, or NULL if none is found. This result can be -passed back into a recurring call as the _next_ parameter of the function. - -_tep_cmdline_pid()_ functions returns the pid for the give cmdline. If _cmdline_ - is NULL, then -1 is returned. - -EXAMPLE -------- -The following example registers pid for command "ls", in context of event _tep_ -and performs various searches for pid / process name mappings: -[source,c] --- -#include <event-parse.h> -... -int ret; -int ls_pid = 1021; -struct tep_handle *tep = tep_alloc(); -... - ret = tep_register_comm(tep, "ls", ls_pid); - if (ret != 0 && errno == EEXIST) - ret = tep_override_comm(tep, "ls", ls_pid); - if (ret != 0) { - /* Failed to register pid / command mapping */ - } -... - if (tep_is_pid_registered(tep, ls_pid) == 0) { - /* Command mapping for ls_pid is not registered */ - } -... - const char *comm = tep_data_comm_from_pid(tep, ls_pid); - if (comm) { - /* Found process name for ls_pid */ - } -... - int pid; - struct cmdline *cmd = tep_data_pid_from_comm(tep, "ls", NULL); - while (cmd) { - pid = tep_cmdline_pid(tep, cmd); - /* Found pid for process "ls" */ - cmd = tep_data_pid_from_comm(tep, "ls", cmd); - } --- -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 |