/* * If TRACE_SYSTEM is defined, that will be the directory created * in the ftrace directory under /sys/kernel/debug/tracing/events/ * * The define_trace.h below will also look for a file name of * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here. * In this case, it would look for sample.h * * If the header name will be different than the system name * (as in this case), then you can override the header name that * define_trace.h will look up by defining TRACE_INCLUDE_FILE * * This file is called trace-events-sample.h but we want the system * to be called "sample". Therefore we must define the name of this * file: * * #define TRACE_INCLUDE_FILE trace-events-sample * * As we do an the bottom of this file. * * Notice that TRACE_SYSTEM should be defined outside of #if * protection, just like TRACE_INCLUDE_FILE. */ #undef TRACE_SYSTEM #define TRACE_SYSTEM ccci /* * Notice that this file is not protected like a normal header. * We also must allow for rereading of this file. The * * || defined(TRACE_HEADER_MULTI_READ) * * serves this purpose. */ #if !defined(_TRACE_EVENT_SAMPLE_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_EVENT_SAMPLE_H /* * All trace headers should include tracepoint.h, until we finally * make it into a standard header. */ #include /* * The TRACE_EVENT macro is broken up into 5 parts. * * name: name of the trace point. This is also how to enable the tracepoint. * A function called trace_foo_bar() will be created. * * proto: the prototype of the function trace_foo_bar() * Here it is trace_foo_bar(char *foo, int bar). * * args: must match the arguments in the prototype. * Here it is simply "foo, bar". * * struct: This defines the way the data will be stored in the ring buffer. * There are currently two types of elements. __field and __array. * a __field is broken up into (type, name). Where type can be any * type but an array. * For an array. there are three fields. (type, name, size). The * type of elements in the array, the name of the field and the size * of the array. * * __array( char, foo, 10) is the same as saying char foo[10]. * * fast_assign: This is a C like function that is used to store the items * into the ring buffer. * * printk: This is a way to print out the data in pretty print. This is * useful if the system crashes and you are logging via a serial line, * the data can be printed to the console using this "printk" method. * * Note, that for both the assign and the printk, __entry is the handler * to the data structure in the ring buffer, and is defined by the * TP_STRUCT__entry. */ TRACE_EVENT(ccci_bm, TP_PROTO(unsigned int req_bool_size, unsigned int bm_pool1_size, unsigned int bm_pool2_size, unsigned int bm_pool3_size), TP_ARGS(req_bool_size, bm_pool1_size, bm_pool2_size, bm_pool3_size), TP_STRUCT__entry(__field(unsigned int, req_bool_size) __field(unsigned int, bm_pool1_size) __field(unsigned int, bm_pool2_size) __field(unsigned int, bm_pool3_size) ), TP_fast_assign(__entry->req_bool_size = req_bool_size; __entry->bm_pool1_size = bm_pool1_size; __entry->bm_pool2_size = bm_pool2_size; __entry->bm_pool3_size = bm_pool3_size;), TP_printk("%u,%u,%u,%u", _entry->req_bool_size, __entry->bm_pool1_size, __entry->bm_pool2_size, __entry->bm_pool3_size) ); #endif /***** NOTICE! The #if protection ends here. *****/ /* * There are several ways I could have done this. If I left out the * TRACE_INCLUDE_PATH, then it would default to the kernel source * include/trace/events directory. * * I could specify a path from the define_trace.h file back to this * file. * * #define TRACE_INCLUDE_PATH ../../samples/trace_events * * But the safest and easiest way to simply make it use the directory * that the file is in is to add in the Makefile: * * CFLAGS_trace-events-sample.o := -I$(src) * * This will make sure the current path is part of the include * structure for our file so that define_trace.h can find it. * * I could have made only the top level directory the include: * * CFLAGS_trace-events-sample.o := -I$(PWD) * * And then let the path to this directory be the TRACE_INCLUDE_PATH: * * #define TRACE_INCLUDE_PATH samples/trace_events * * But then if something defines "samples" or "trace_events" as a macro * then we could risk that being converted too, and give us an unexpected * result. */ #undef TRACE_INCLUDE_PATH #undef TRACE_INCLUDE_FILE #define TRACE_INCLUDE_PATH . /* * TRACE_INCLUDE_FILE is not needed if the filename and TRACE_SYSTEM are equal */ #define TRACE_INCLUDE_FILE ccci_events #include