1*287e80b3SSadaf Ebrahimilibtracefs(3) 2*287e80b3SSadaf Ebrahimi============= 3*287e80b3SSadaf Ebrahimi 4*287e80b3SSadaf EbrahimiNAME 5*287e80b3SSadaf Ebrahimi---- 6*287e80b3SSadaf Ebrahimitracefs_option_enable, tracefs_option_disable, tracefs_option_name - 7*287e80b3SSadaf EbrahimiVarious trace option functions. 8*287e80b3SSadaf Ebrahimi 9*287e80b3SSadaf EbrahimiSYNOPSIS 10*287e80b3SSadaf Ebrahimi-------- 11*287e80b3SSadaf Ebrahimi[verse] 12*287e80b3SSadaf Ebrahimi-- 13*287e80b3SSadaf Ebrahimi*#include <tracefs.h>* 14*287e80b3SSadaf Ebrahimi 15*287e80b3SSadaf Ebrahimiint *tracefs_option_enable*(struct tracefs_instance pass:[*]_instance_, enum tracefs_option_id _id_); 16*287e80b3SSadaf Ebrahimiint *tracefs_option_disable*(struct tracefs_instance pass:[*]_instance_, enum tracefs_option_id _id_); 17*287e80b3SSadaf Ebrahimiconst char pass:[*]*tracefs_option_name*(enum tracefs_option_id _id_); 18*287e80b3SSadaf Ebrahimi-- 19*287e80b3SSadaf Ebrahimi 20*287e80b3SSadaf EbrahimiDESCRIPTION 21*287e80b3SSadaf Ebrahimi----------- 22*287e80b3SSadaf EbrahimiThis set of APIs can be used to enable and disable ftrace options and to get the name of an option. 23*287e80b3SSadaf Ebrahimi 24*287e80b3SSadaf EbrahimiThe *tracefs_option_enable()* function enables the option with _id_ in the given _instance_. If 25*287e80b3SSadaf Ebrahimi_instance_ is NULL, the option is enabled in the top trace instance. 26*287e80b3SSadaf Ebrahimi 27*287e80b3SSadaf EbrahimiThe *tracefs_option_disable()* function disables the option with _id_ in the given _instance_. If 28*287e80b3SSadaf Ebrahimi_instance_ is NULL, the option is disabled in the top trace instance. 29*287e80b3SSadaf Ebrahimi 30*287e80b3SSadaf EbrahimiThe *tracefs_option_name()* function returns a string, representing the option with _id_. The string 31*287e80b3SSadaf Ebrahimimust *not* be freed. 32*287e80b3SSadaf Ebrahimi 33*287e80b3SSadaf Ebrahimi 34*287e80b3SSadaf EbrahimiRETURN VALUE 35*287e80b3SSadaf Ebrahimi------------ 36*287e80b3SSadaf EbrahimiThe *tracefs_option_enable()* and *tracefs_option_disable()* functions return 0 if the state of the 37*287e80b3SSadaf Ebrahimioption is set successfully, or -1 in case of an error. 38*287e80b3SSadaf Ebrahimi 39*287e80b3SSadaf EbrahimiThe *tracefs_option_name()* function returns string with option name, or "unknown" in case of an 40*287e80b3SSadaf Ebrahimierror. The returned string must *not* be freed. 41*287e80b3SSadaf Ebrahimi 42*287e80b3SSadaf EbrahimiEXAMPLE 43*287e80b3SSadaf Ebrahimi------- 44*287e80b3SSadaf Ebrahimi[source,c] 45*287e80b3SSadaf Ebrahimi-- 46*287e80b3SSadaf Ebrahimi#include <tracefs.h> 47*287e80b3SSadaf Ebrahimi... 48*287e80b3SSadaf Ebrahimiif (tracefs_option_enable(NULL, TRACEFS_OPTION_ANNOTATE)) { 49*287e80b3SSadaf Ebrahimi /* Failed to enable annotate option in top trace instance */ 50*287e80b3SSadaf Ebrahimi} 51*287e80b3SSadaf Ebrahimi... 52*287e80b3SSadaf Ebrahimiif (tracefs_option_disable(NULL, TRACEFS_OPTION_CONTEXT_INFO)) { 53*287e80b3SSadaf Ebrahimi /* Failed to disable context info option in top trace instance */ 54*287e80b3SSadaf Ebrahimi} 55*287e80b3SSadaf Ebrahimi... 56*287e80b3SSadaf Ebrahimichar *name = tracefs_option_name(TRACEFS_OPTION_FUNC_STACKTRACE); 57*287e80b3SSadaf Ebrahimiif (strcmp(name, "unknown")) { 58*287e80b3SSadaf Ebrahimi /* Cannot get the name of the option */ 59*287e80b3SSadaf Ebrahimi} 60*287e80b3SSadaf Ebrahimi 61*287e80b3SSadaf Ebrahimi-- 62*287e80b3SSadaf EbrahimiFILES 63*287e80b3SSadaf Ebrahimi----- 64*287e80b3SSadaf Ebrahimi[verse] 65*287e80b3SSadaf Ebrahimi-- 66*287e80b3SSadaf Ebrahimi*tracefs.h* 67*287e80b3SSadaf Ebrahimi Header file to include in order to have access to the library APIs. 68*287e80b3SSadaf Ebrahimi*-ltracefs* 69*287e80b3SSadaf Ebrahimi Linker switch to add when building a program that uses the library. 70*287e80b3SSadaf Ebrahimi-- 71*287e80b3SSadaf Ebrahimi 72*287e80b3SSadaf EbrahimiSEE ALSO 73*287e80b3SSadaf Ebrahimi-------- 74*287e80b3SSadaf Ebrahimi*libtracefs*(3), 75*287e80b3SSadaf Ebrahimi*libtraceevent*(3), 76*287e80b3SSadaf Ebrahimi*trace-cmd*(1) 77*287e80b3SSadaf Ebrahimi 78*287e80b3SSadaf EbrahimiAUTHOR 79*287e80b3SSadaf Ebrahimi------ 80*287e80b3SSadaf Ebrahimi[verse] 81*287e80b3SSadaf Ebrahimi-- 82*287e80b3SSadaf Ebrahimi*Steven Rostedt* <[email protected]> 83*287e80b3SSadaf Ebrahimi*Tzvetomir Stoyanov* <[email protected]> 84*287e80b3SSadaf Ebrahimi-- 85*287e80b3SSadaf EbrahimiREPORTING BUGS 86*287e80b3SSadaf Ebrahimi-------------- 87*287e80b3SSadaf EbrahimiReport bugs to <[email protected]> 88*287e80b3SSadaf Ebrahimi 89*287e80b3SSadaf EbrahimiLICENSE 90*287e80b3SSadaf Ebrahimi------- 91*287e80b3SSadaf Ebrahimilibtracefs is Free Software licensed under the GNU LGPL 2.1 92*287e80b3SSadaf Ebrahimi 93*287e80b3SSadaf EbrahimiRESOURCES 94*287e80b3SSadaf Ebrahimi--------- 95*287e80b3SSadaf Ebrahimihttps://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/ 96*287e80b3SSadaf Ebrahimi 97*287e80b3SSadaf EbrahimiCOPYING 98*287e80b3SSadaf Ebrahimi------- 99*287e80b3SSadaf EbrahimiCopyright \(C) 2020 VMware, Inc. Free use of this software is granted under 100*287e80b3SSadaf Ebrahimithe terms of the GNU Public License (GPL). 101