1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */ 29cfe06f8SSteven Rostedt /* 39cfe06f8SSteven Rostedt * If TRACE_SYSTEM is defined, that will be the directory created 44e20e3a6SSteven Rostedt (Red Hat) * in the ftrace directory under /sys/kernel/tracing/events/<system> 59cfe06f8SSteven Rostedt * 644ad18e0SSteven Rostedt * The define_trace.h below will also look for a file name of 79cfe06f8SSteven Rostedt * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here. 867aedeb8SChunyan Zhang * In this case, it would look for sample-trace.h 99cfe06f8SSteven Rostedt * 1044ad18e0SSteven Rostedt * If the header name will be different than the system name 1144ad18e0SSteven Rostedt * (as in this case), then you can override the header name that 1244ad18e0SSteven Rostedt * define_trace.h will look up by defining TRACE_INCLUDE_FILE 139cfe06f8SSteven Rostedt * 1444ad18e0SSteven Rostedt * This file is called trace-events-sample.h but we want the system 1567aedeb8SChunyan Zhang * to be called "sample-trace". Therefore we must define the name of this 1644ad18e0SSteven Rostedt * file: 179cfe06f8SSteven Rostedt * 1844ad18e0SSteven Rostedt * #define TRACE_INCLUDE_FILE trace-events-sample 199cfe06f8SSteven Rostedt * 2044ad18e0SSteven Rostedt * As we do an the bottom of this file. 21d0b6e04aSLi Zefan * 22d0b6e04aSLi Zefan * Notice that TRACE_SYSTEM should be defined outside of #if 23d0b6e04aSLi Zefan * protection, just like TRACE_INCLUDE_FILE. 249cfe06f8SSteven Rostedt */ 259cfe06f8SSteven Rostedt #undef TRACE_SYSTEM 2688920427SSteven Rostedt (Red Hat) #define TRACE_SYSTEM sample-trace 2788920427SSteven Rostedt (Red Hat) 2888920427SSteven Rostedt (Red Hat) /* 2988920427SSteven Rostedt (Red Hat) * TRACE_SYSTEM is expected to be a C valid variable (alpha-numeric 3088920427SSteven Rostedt (Red Hat) * and underscore), although it may start with numbers. If for some 3188920427SSteven Rostedt (Red Hat) * reason it is not, you need to add the following lines: 3288920427SSteven Rostedt (Red Hat) */ 3388920427SSteven Rostedt (Red Hat) #undef TRACE_SYSTEM_VAR 3488920427SSteven Rostedt (Red Hat) #define TRACE_SYSTEM_VAR sample_trace 3588920427SSteven Rostedt (Red Hat) /* 3688920427SSteven Rostedt (Red Hat) * But the above is only needed if TRACE_SYSTEM is not alpha-numeric 3788920427SSteven Rostedt (Red Hat) * and underscored. By default, TRACE_SYSTEM_VAR will be equal to 3888920427SSteven Rostedt (Red Hat) * TRACE_SYSTEM. As TRACE_SYSTEM_VAR must be alpha-numeric, if 3988920427SSteven Rostedt (Red Hat) * TRACE_SYSTEM is not, then TRACE_SYSTEM_VAR must be defined with 4088920427SSteven Rostedt (Red Hat) * only alpha-numeric and underscores. 4188920427SSteven Rostedt (Red Hat) * 4288920427SSteven Rostedt (Red Hat) * The TRACE_SYSTEM_VAR is only used internally and not visible to 4388920427SSteven Rostedt (Red Hat) * user space. 4488920427SSteven Rostedt (Red Hat) */ 459cfe06f8SSteven Rostedt 469cfe06f8SSteven Rostedt /* 47d0b6e04aSLi Zefan * Notice that this file is not protected like a normal header. 48d0b6e04aSLi Zefan * We also must allow for rereading of this file. The 49d0b6e04aSLi Zefan * 50d0b6e04aSLi Zefan * || defined(TRACE_HEADER_MULTI_READ) 51d0b6e04aSLi Zefan * 52d0b6e04aSLi Zefan * serves this purpose. 53d0b6e04aSLi Zefan */ 54d0b6e04aSLi Zefan #if !defined(_TRACE_EVENT_SAMPLE_H) || defined(TRACE_HEADER_MULTI_READ) 55d0b6e04aSLi Zefan #define _TRACE_EVENT_SAMPLE_H 56d0b6e04aSLi Zefan 57d0b6e04aSLi Zefan /* 58d0b6e04aSLi Zefan * All trace headers should include tracepoint.h, until we finally 59d0b6e04aSLi Zefan * make it into a standard header. 60d0b6e04aSLi Zefan */ 61d0b6e04aSLi Zefan #include <linux/tracepoint.h> 62d0b6e04aSLi Zefan 63d0b6e04aSLi Zefan /* 649cfe06f8SSteven Rostedt * The TRACE_EVENT macro is broken up into 5 parts. 659cfe06f8SSteven Rostedt * 669cfe06f8SSteven Rostedt * name: name of the trace point. This is also how to enable the tracepoint. 679cfe06f8SSteven Rostedt * A function called trace_foo_bar() will be created. 689cfe06f8SSteven Rostedt * 699cfe06f8SSteven Rostedt * proto: the prototype of the function trace_foo_bar() 709cfe06f8SSteven Rostedt * Here it is trace_foo_bar(char *foo, int bar). 719cfe06f8SSteven Rostedt * 729cfe06f8SSteven Rostedt * args: must match the arguments in the prototype. 739cfe06f8SSteven Rostedt * Here it is simply "foo, bar". 749cfe06f8SSteven Rostedt * 759cfe06f8SSteven Rostedt * struct: This defines the way the data will be stored in the ring buffer. 764e20e3a6SSteven Rostedt (Red Hat) * The items declared here become part of a special structure 774e20e3a6SSteven Rostedt (Red Hat) * called "__entry", which can be used in the fast_assign part of the 784e20e3a6SSteven Rostedt (Red Hat) * TRACE_EVENT macro. 799cfe06f8SSteven Rostedt * 804e20e3a6SSteven Rostedt (Red Hat) * Here are the currently defined types you can use: 814e20e3a6SSteven Rostedt (Red Hat) * 824e20e3a6SSteven Rostedt (Red Hat) * __field : Is broken up into type and name. Where type can be any 834e20e3a6SSteven Rostedt (Red Hat) * primitive type (integer, long or pointer). 844e20e3a6SSteven Rostedt (Red Hat) * 854e20e3a6SSteven Rostedt (Red Hat) * __field(int, foo) 864e20e3a6SSteven Rostedt (Red Hat) * 874e20e3a6SSteven Rostedt (Red Hat) * __entry->foo = 5; 884e20e3a6SSteven Rostedt (Red Hat) * 894e20e3a6SSteven Rostedt (Red Hat) * __field_struct : This can be any static complex data type (struct, union 904e20e3a6SSteven Rostedt (Red Hat) * but not an array). Be careful using complex types, as each 914e20e3a6SSteven Rostedt (Red Hat) * event is limited in size, and copying large amounts of data 924e20e3a6SSteven Rostedt (Red Hat) * into the ring buffer can slow things down. 934e20e3a6SSteven Rostedt (Red Hat) * 944e20e3a6SSteven Rostedt (Red Hat) * __field_struct(struct bar, foo) 954e20e3a6SSteven Rostedt (Red Hat) * 964e20e3a6SSteven Rostedt (Red Hat) * __entry->bar.x = y; 974e20e3a6SSteven Rostedt (Red Hat) 984e20e3a6SSteven Rostedt (Red Hat) * __array: There are three fields (type, name, size). The type is the 9927019975SJeremy Linton * type of elements in the array, the name is the name of the array. 1004e20e3a6SSteven Rostedt (Red Hat) * size is the number of items in the array (not the total size). 1014e20e3a6SSteven Rostedt (Red Hat) * 1024e20e3a6SSteven Rostedt (Red Hat) * __array( char, foo, 10) is the same as saying: char foo[10]; 1034e20e3a6SSteven Rostedt (Red Hat) * 1044e20e3a6SSteven Rostedt (Red Hat) * Assigning arrays can be done like any array: 1054e20e3a6SSteven Rostedt (Red Hat) * 1064e20e3a6SSteven Rostedt (Red Hat) * __entry->foo[0] = 'a'; 1074e20e3a6SSteven Rostedt (Red Hat) * 1084e20e3a6SSteven Rostedt (Red Hat) * memcpy(__entry->foo, bar, 10); 1094e20e3a6SSteven Rostedt (Red Hat) * 11067aedeb8SChunyan Zhang * __dynamic_array: This is similar to array, but can vary its size from 1114e20e3a6SSteven Rostedt (Red Hat) * instance to instance of the tracepoint being called. 1124e20e3a6SSteven Rostedt (Red Hat) * Like __array, this too has three elements (type, name, size); 1134e20e3a6SSteven Rostedt (Red Hat) * type is the type of the element, name is the name of the array. 1144e20e3a6SSteven Rostedt (Red Hat) * The size is different than __array. It is not a static number, 1154e20e3a6SSteven Rostedt (Red Hat) * but the algorithm to figure out the length of the array for the 11627019975SJeremy Linton * specific instance of tracepoint. Again, size is the number of 1174e20e3a6SSteven Rostedt (Red Hat) * items in the array, not the total length in bytes. 1184e20e3a6SSteven Rostedt (Red Hat) * 1194e20e3a6SSteven Rostedt (Red Hat) * __dynamic_array( int, foo, bar) is similar to: int foo[bar]; 1204e20e3a6SSteven Rostedt (Red Hat) * 1214e20e3a6SSteven Rostedt (Red Hat) * Note, unlike arrays, you must use the __get_dynamic_array() macro 1224e20e3a6SSteven Rostedt (Red Hat) * to access the array. 1234e20e3a6SSteven Rostedt (Red Hat) * 1244e20e3a6SSteven Rostedt (Red Hat) * memcpy(__get_dynamic_array(foo), bar, 10); 1254e20e3a6SSteven Rostedt (Red Hat) * 1264e20e3a6SSteven Rostedt (Red Hat) * Notice, that "__entry" is not needed here. 1274e20e3a6SSteven Rostedt (Red Hat) * 1284e20e3a6SSteven Rostedt (Red Hat) * __string: This is a special kind of __dynamic_array. It expects to 12927019975SJeremy Linton * have a null terminated character array passed to it (it allows 1304e20e3a6SSteven Rostedt (Red Hat) * for NULL too, which would be converted into "(null)"). __string 13127019975SJeremy Linton * takes two parameter (name, src), where name is the name of 1324e20e3a6SSteven Rostedt (Red Hat) * the string saved, and src is the string to copy into the 1334e20e3a6SSteven Rostedt (Red Hat) * ring buffer. 1344e20e3a6SSteven Rostedt (Red Hat) * 1354e20e3a6SSteven Rostedt (Red Hat) * __string(foo, bar) is similar to: strcpy(foo, bar) 1364e20e3a6SSteven Rostedt (Red Hat) * 1374e20e3a6SSteven Rostedt (Red Hat) * To assign a string, use the helper macro __assign_str(). 1384e20e3a6SSteven Rostedt (Red Hat) * 1394e20e3a6SSteven Rostedt (Red Hat) * __assign_str(foo, bar); 1404e20e3a6SSteven Rostedt (Red Hat) * 1414e20e3a6SSteven Rostedt (Red Hat) * In most cases, the __assign_str() macro will take the same 1424e20e3a6SSteven Rostedt (Red Hat) * parameters as the __string() macro had to declare the string. 1434e20e3a6SSteven Rostedt (Red Hat) * 144fea6ac55SSteven Rostedt (Google) * __vstring: This is similar to __string() but instead of taking a 145fea6ac55SSteven Rostedt (Google) * dynamic length, it takes a variable list va_list 'va' variable. 146fea6ac55SSteven Rostedt (Google) * Some event callers already have a message from parameters saved 147fea6ac55SSteven Rostedt (Google) * in a va_list. Passing in the format and the va_list variable 148fea6ac55SSteven Rostedt (Google) * will save just enough on the ring buffer for that string. 149fea6ac55SSteven Rostedt (Google) * Note, the va variable used is a pointer to a va_list, not 150fea6ac55SSteven Rostedt (Google) * to the va_list directly. 151fea6ac55SSteven Rostedt (Google) * 152fea6ac55SSteven Rostedt (Google) * (va_list *va) 153fea6ac55SSteven Rostedt (Google) * 154fea6ac55SSteven Rostedt (Google) * __vstring(foo, fmt, va) is similar to: vsnprintf(foo, fmt, va) 155fea6ac55SSteven Rostedt (Google) * 156fea6ac55SSteven Rostedt (Google) * To assign the string, use the helper macro __assign_vstr(). 157fea6ac55SSteven Rostedt (Google) * 158fea6ac55SSteven Rostedt (Google) * __assign_vstr(foo, fmt, va); 159fea6ac55SSteven Rostedt (Google) * 160fea6ac55SSteven Rostedt (Google) * In most cases, the __assign_vstr() macro will take the same 161fea6ac55SSteven Rostedt (Google) * parameters as the __vstring() macro had to declare the string. 162fea6ac55SSteven Rostedt (Google) * Use __get_str() to retrieve the __vstring() just like it would for 163fea6ac55SSteven Rostedt (Google) * __string(). 164fea6ac55SSteven Rostedt (Google) * 165883b4aeeSSteven Rostedt (VMware) * __string_len: This is a helper to a __dynamic_array, but it understands 166883b4aeeSSteven Rostedt (VMware) * that the array has characters in it, and with the combined 167883b4aeeSSteven Rostedt (VMware) * use of __assign_str_len(), it will allocate 'len' + 1 bytes 168883b4aeeSSteven Rostedt (VMware) * in the ring buffer and add a '\0' to the string. This is 169883b4aeeSSteven Rostedt (VMware) * useful if the string being saved has no terminating '\0' byte. 170883b4aeeSSteven Rostedt (VMware) * It requires that the length of the string is known as it acts 171883b4aeeSSteven Rostedt (VMware) * like a memcpy(). 172883b4aeeSSteven Rostedt (VMware) * 173883b4aeeSSteven Rostedt (VMware) * Declared with: 174883b4aeeSSteven Rostedt (VMware) * 175883b4aeeSSteven Rostedt (VMware) * __string_len(foo, bar, len) 176883b4aeeSSteven Rostedt (VMware) * 177883b4aeeSSteven Rostedt (VMware) * To assign this string, use the helper macro __assign_str_len(). 178883b4aeeSSteven Rostedt (VMware) * 179ecbe794eSGeliang Tang * __assign_str_len(foo, bar, len); 180883b4aeeSSteven Rostedt (VMware) * 181883b4aeeSSteven Rostedt (VMware) * Then len + 1 is allocated to the ring buffer, and a nul terminating 182883b4aeeSSteven Rostedt (VMware) * byte is added. This is similar to: 183883b4aeeSSteven Rostedt (VMware) * 184883b4aeeSSteven Rostedt (VMware) * memcpy(__get_str(foo), bar, len); 185883b4aeeSSteven Rostedt (VMware) * __get_str(foo)[len] = 0; 186883b4aeeSSteven Rostedt (VMware) * 187883b4aeeSSteven Rostedt (VMware) * The advantage of using this over __dynamic_array, is that it 188883b4aeeSSteven Rostedt (VMware) * takes care of allocating the extra byte on the ring buffer 189883b4aeeSSteven Rostedt (VMware) * for the '\0' terminating byte, and __get_str(foo) can be used 190883b4aeeSSteven Rostedt (VMware) * in the TP_printk(). 191883b4aeeSSteven Rostedt (VMware) * 1924e20e3a6SSteven Rostedt (Red Hat) * __bitmask: This is another kind of __dynamic_array, but it expects 1934e20e3a6SSteven Rostedt (Red Hat) * an array of longs, and the number of bits to parse. It takes 1944e20e3a6SSteven Rostedt (Red Hat) * two parameters (name, nr_bits), where name is the name of the 1954e20e3a6SSteven Rostedt (Red Hat) * bitmask to save, and the nr_bits is the number of bits to record. 1964e20e3a6SSteven Rostedt (Red Hat) * 1974e20e3a6SSteven Rostedt (Red Hat) * __bitmask(target_cpu, nr_cpumask_bits) 1984e20e3a6SSteven Rostedt (Red Hat) * 1994e20e3a6SSteven Rostedt (Red Hat) * To assign a bitmask, use the __assign_bitmask() helper macro. 2004e20e3a6SSteven Rostedt (Red Hat) * 2014e20e3a6SSteven Rostedt (Red Hat) * __assign_bitmask(target_cpus, cpumask_bits(bar), nr_cpumask_bits); 2024e20e3a6SSteven Rostedt (Red Hat) * 203*8230f27bSSteven Rostedt (Google) * __cpumask: This is pretty much the same as __bitmask but is specific for 204*8230f27bSSteven Rostedt (Google) * CPU masks. The type displayed to the user via the format files will 205*8230f27bSSteven Rostedt (Google) * be "cpumaks_t" such that user space may deal with them differently 206*8230f27bSSteven Rostedt (Google) * if they choose to do so, and the bits is always set to nr_cpumask_bits. 207*8230f27bSSteven Rostedt (Google) * 208*8230f27bSSteven Rostedt (Google) * __cpumask(target_cpu) 209*8230f27bSSteven Rostedt (Google) * 210*8230f27bSSteven Rostedt (Google) * To assign a cpumask, use the __assign_cpumask() helper macro. 211*8230f27bSSteven Rostedt (Google) * 212*8230f27bSSteven Rostedt (Google) * __assign_cpumask(target_cpus, cpumask_bits(bar)); 2139cfe06f8SSteven Rostedt * 2149cfe06f8SSteven Rostedt * fast_assign: This is a C like function that is used to store the items 2154e20e3a6SSteven Rostedt (Red Hat) * into the ring buffer. A special variable called "__entry" will be the 2164e20e3a6SSteven Rostedt (Red Hat) * structure that points into the ring buffer and has the same fields as 2174e20e3a6SSteven Rostedt (Red Hat) * described by the struct part of TRACE_EVENT above. 2189cfe06f8SSteven Rostedt * 2199cfe06f8SSteven Rostedt * printk: This is a way to print out the data in pretty print. This is 2209cfe06f8SSteven Rostedt * useful if the system crashes and you are logging via a serial line, 2219cfe06f8SSteven Rostedt * the data can be printed to the console using this "printk" method. 2224e20e3a6SSteven Rostedt (Red Hat) * This is also used to print out the data from the trace files. 2234e20e3a6SSteven Rostedt (Red Hat) * Again, the __entry macro is used to access the data from the ring buffer. 2244e20e3a6SSteven Rostedt (Red Hat) * 225*8230f27bSSteven Rostedt (Google) * Note, __dynamic_array, __string, __bitmask and __cpumask require special 226*8230f27bSSteven Rostedt (Google) * helpers to access the data. 2274e20e3a6SSteven Rostedt (Red Hat) * 2284e20e3a6SSteven Rostedt (Red Hat) * For __dynamic_array(int, foo, bar) use __get_dynamic_array(foo) 2294e20e3a6SSteven Rostedt (Red Hat) * Use __get_dynamic_array_len(foo) to get the length of the array 230d6726c81SSteven Rostedt (Red Hat) * saved. Note, __get_dynamic_array_len() returns the total allocated 231d6726c81SSteven Rostedt (Red Hat) * length of the dynamic array; __print_array() expects the second 232d6726c81SSteven Rostedt (Red Hat) * parameter to be the number of elements. To get that, the array length 233d6726c81SSteven Rostedt (Red Hat) * needs to be divided by the element size. 2344e20e3a6SSteven Rostedt (Red Hat) * 2354e20e3a6SSteven Rostedt (Red Hat) * For __string(foo, bar) use __get_str(foo) 2364e20e3a6SSteven Rostedt (Red Hat) * 2374e20e3a6SSteven Rostedt (Red Hat) * For __bitmask(target_cpus, nr_cpumask_bits) use __get_bitmask(target_cpus) 2384e20e3a6SSteven Rostedt (Red Hat) * 239*8230f27bSSteven Rostedt (Google) * For __cpumask(target_cpus) use __get_cpumask(target_cpus) 240*8230f27bSSteven Rostedt (Google) * 2419cfe06f8SSteven Rostedt * 2429cfe06f8SSteven Rostedt * Note, that for both the assign and the printk, __entry is the handler 2439cfe06f8SSteven Rostedt * to the data structure in the ring buffer, and is defined by the 2449cfe06f8SSteven Rostedt * TP_STRUCT__entry. 2459cfe06f8SSteven Rostedt */ 2464e20e3a6SSteven Rostedt (Red Hat) 2474e20e3a6SSteven Rostedt (Red Hat) /* 2484e20e3a6SSteven Rostedt (Red Hat) * It is OK to have helper functions in the file, but they need to be protected 2494e20e3a6SSteven Rostedt (Red Hat) * from being defined more than once. Remember, this file gets included more 2504e20e3a6SSteven Rostedt (Red Hat) * than once. 2514e20e3a6SSteven Rostedt (Red Hat) */ 2524e20e3a6SSteven Rostedt (Red Hat) #ifndef __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS 2534e20e3a6SSteven Rostedt (Red Hat) #define __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS 2544e20e3a6SSteven Rostedt (Red Hat) static inline int __length_of(const int *list) 2554e20e3a6SSteven Rostedt (Red Hat) { 2564e20e3a6SSteven Rostedt (Red Hat) int i; 2574e20e3a6SSteven Rostedt (Red Hat) 2584e20e3a6SSteven Rostedt (Red Hat) if (!list) 2594e20e3a6SSteven Rostedt (Red Hat) return 0; 2604e20e3a6SSteven Rostedt (Red Hat) 2614e20e3a6SSteven Rostedt (Red Hat) for (i = 0; list[i]; i++) 2624e20e3a6SSteven Rostedt (Red Hat) ; 2634e20e3a6SSteven Rostedt (Red Hat) return i; 2644e20e3a6SSteven Rostedt (Red Hat) } 26532eb3d0dSSteven Rostedt (Red Hat) 26632eb3d0dSSteven Rostedt (Red Hat) enum { 26732eb3d0dSSteven Rostedt (Red Hat) TRACE_SAMPLE_FOO = 2, 26832eb3d0dSSteven Rostedt (Red Hat) TRACE_SAMPLE_BAR = 4, 26932eb3d0dSSteven Rostedt (Red Hat) TRACE_SAMPLE_ZOO = 8, 27032eb3d0dSSteven Rostedt (Red Hat) }; 2714e20e3a6SSteven Rostedt (Red Hat) #endif 2724e20e3a6SSteven Rostedt (Red Hat) 27332eb3d0dSSteven Rostedt (Red Hat) /* 27432eb3d0dSSteven Rostedt (Red Hat) * If enums are used in the TP_printk(), their names will be shown in 27532eb3d0dSSteven Rostedt (Red Hat) * format files and not their values. This can cause problems with user 27632eb3d0dSSteven Rostedt (Red Hat) * space programs that parse the format files to know how to translate 27732eb3d0dSSteven Rostedt (Red Hat) * the raw binary trace output into human readable text. 27832eb3d0dSSteven Rostedt (Red Hat) * 27932eb3d0dSSteven Rostedt (Red Hat) * To help out user space programs, any enum that is used in the TP_printk() 28032eb3d0dSSteven Rostedt (Red Hat) * should be defined by TRACE_DEFINE_ENUM() macro. All that is needed to 28132eb3d0dSSteven Rostedt (Red Hat) * be done is to add this macro with the enum within it in the trace 28232eb3d0dSSteven Rostedt (Red Hat) * header file, and it will be converted in the output. 28332eb3d0dSSteven Rostedt (Red Hat) */ 28432eb3d0dSSteven Rostedt (Red Hat) 28532eb3d0dSSteven Rostedt (Red Hat) TRACE_DEFINE_ENUM(TRACE_SAMPLE_FOO); 28632eb3d0dSSteven Rostedt (Red Hat) TRACE_DEFINE_ENUM(TRACE_SAMPLE_BAR); 28732eb3d0dSSteven Rostedt (Red Hat) TRACE_DEFINE_ENUM(TRACE_SAMPLE_ZOO); 28832eb3d0dSSteven Rostedt (Red Hat) 2899cfe06f8SSteven Rostedt TRACE_EVENT(foo_bar, 2909cfe06f8SSteven Rostedt 2914e20e3a6SSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar, const int *lst, 292fea6ac55SSteven Rostedt (Google) const char *string, const struct cpumask *mask, 293fea6ac55SSteven Rostedt (Google) const char *fmt, va_list *va), 2949cfe06f8SSteven Rostedt 295fea6ac55SSteven Rostedt (Google) TP_ARGS(foo, bar, lst, string, mask, fmt, va), 2969cfe06f8SSteven Rostedt 2979cfe06f8SSteven Rostedt TP_STRUCT__entry( 2989cfe06f8SSteven Rostedt __array( char, foo, 10 ) 2999cfe06f8SSteven Rostedt __field( int, bar ) 3004e20e3a6SSteven Rostedt (Red Hat) __dynamic_array(int, list, __length_of(lst)) 3014e20e3a6SSteven Rostedt (Red Hat) __string( str, string ) 3024e20e3a6SSteven Rostedt (Red Hat) __bitmask( cpus, num_possible_cpus() ) 303*8230f27bSSteven Rostedt (Google) __cpumask( cpum ) 304fea6ac55SSteven Rostedt (Google) __vstring( vstr, fmt, va ) 3059cfe06f8SSteven Rostedt ), 3069cfe06f8SSteven Rostedt 3079cfe06f8SSteven Rostedt TP_fast_assign( 308d8fae2f6SZhao Hongjiang strlcpy(__entry->foo, foo, 10); 3099cfe06f8SSteven Rostedt __entry->bar = bar; 3104e20e3a6SSteven Rostedt (Red Hat) memcpy(__get_dynamic_array(list), lst, 3114e20e3a6SSteven Rostedt (Red Hat) __length_of(lst) * sizeof(int)); 3124e20e3a6SSteven Rostedt (Red Hat) __assign_str(str, string); 313fea6ac55SSteven Rostedt (Google) __assign_vstr(vstr, fmt, va); 3144e20e3a6SSteven Rostedt (Red Hat) __assign_bitmask(cpus, cpumask_bits(mask), num_possible_cpus()); 315*8230f27bSSteven Rostedt (Google) __assign_cpumask(cpum, cpumask_bits(mask)); 3169cfe06f8SSteven Rostedt ), 3179cfe06f8SSteven Rostedt 318*8230f27bSSteven Rostedt (Google) TP_printk("foo %s %d %s %s %s %s (%s) (%s) %s", __entry->foo, __entry->bar, 31932eb3d0dSSteven Rostedt (Red Hat) 32032eb3d0dSSteven Rostedt (Red Hat) /* 32132eb3d0dSSteven Rostedt (Red Hat) * Notice here the use of some helper functions. This includes: 32232eb3d0dSSteven Rostedt (Red Hat) * 32332eb3d0dSSteven Rostedt (Red Hat) * __print_symbolic( variable, { value, "string" }, ... ), 32432eb3d0dSSteven Rostedt (Red Hat) * 32532eb3d0dSSteven Rostedt (Red Hat) * The variable is tested against each value of the { } pair. If 32632eb3d0dSSteven Rostedt (Red Hat) * the variable matches one of the values, then it will print the 32732eb3d0dSSteven Rostedt (Red Hat) * string in that pair. If non are matched, it returns a string 32832eb3d0dSSteven Rostedt (Red Hat) * version of the number (if __entry->bar == 7 then "7" is returned). 32932eb3d0dSSteven Rostedt (Red Hat) */ 33032eb3d0dSSteven Rostedt (Red Hat) __print_symbolic(__entry->bar, 33132eb3d0dSSteven Rostedt (Red Hat) { 0, "zero" }, 33232eb3d0dSSteven Rostedt (Red Hat) { TRACE_SAMPLE_FOO, "TWO" }, 33332eb3d0dSSteven Rostedt (Red Hat) { TRACE_SAMPLE_BAR, "FOUR" }, 33432eb3d0dSSteven Rostedt (Red Hat) { TRACE_SAMPLE_ZOO, "EIGHT" }, 33532eb3d0dSSteven Rostedt (Red Hat) { 10, "TEN" } 33632eb3d0dSSteven Rostedt (Red Hat) ), 33732eb3d0dSSteven Rostedt (Red Hat) 33832eb3d0dSSteven Rostedt (Red Hat) /* 33932eb3d0dSSteven Rostedt (Red Hat) * __print_flags( variable, "delim", { value, "flag" }, ... ), 34032eb3d0dSSteven Rostedt (Red Hat) * 34132eb3d0dSSteven Rostedt (Red Hat) * This is similar to __print_symbolic, except that it tests the bits 34232eb3d0dSSteven Rostedt (Red Hat) * of the value. If ((FLAG & variable) == FLAG) then the string is 34332eb3d0dSSteven Rostedt (Red Hat) * printed. If more than one flag matches, then each one that does is 34432eb3d0dSSteven Rostedt (Red Hat) * also printed with delim in between them. 34532eb3d0dSSteven Rostedt (Red Hat) * If not all bits are accounted for, then the not found bits will be 34632eb3d0dSSteven Rostedt (Red Hat) * added in hex format: 0x506 will show BIT2|BIT4|0x500 34732eb3d0dSSteven Rostedt (Red Hat) */ 34832eb3d0dSSteven Rostedt (Red Hat) __print_flags(__entry->bar, "|", 34932eb3d0dSSteven Rostedt (Red Hat) { 1, "BIT1" }, 35032eb3d0dSSteven Rostedt (Red Hat) { 2, "BIT2" }, 35132eb3d0dSSteven Rostedt (Red Hat) { 4, "BIT3" }, 35232eb3d0dSSteven Rostedt (Red Hat) { 8, "BIT4" } 35332eb3d0dSSteven Rostedt (Red Hat) ), 35432eb3d0dSSteven Rostedt (Red Hat) /* 35532eb3d0dSSteven Rostedt (Red Hat) * __print_array( array, len, element_size ) 35632eb3d0dSSteven Rostedt (Red Hat) * 35732eb3d0dSSteven Rostedt (Red Hat) * This prints out the array that is defined by __array in a nice format. 35832eb3d0dSSteven Rostedt (Red Hat) */ 3594e20e3a6SSteven Rostedt (Red Hat) __print_array(__get_dynamic_array(list), 360d6726c81SSteven Rostedt (Red Hat) __get_dynamic_array_len(list) / sizeof(int), 3614e20e3a6SSteven Rostedt (Red Hat) sizeof(int)), 362*8230f27bSSteven Rostedt (Google) __get_str(str), __get_bitmask(cpus), __get_cpumask(cpus), 363*8230f27bSSteven Rostedt (Google) __get_str(vstr)) 3649cfe06f8SSteven Rostedt ); 365c4c7eb29SSteven Rostedt (Red Hat) 366c4c7eb29SSteven Rostedt (Red Hat) /* 367c4c7eb29SSteven Rostedt (Red Hat) * There may be a case where a tracepoint should only be called if 368c4c7eb29SSteven Rostedt (Red Hat) * some condition is set. Otherwise the tracepoint should not be called. 369c4c7eb29SSteven Rostedt (Red Hat) * But to do something like: 370c4c7eb29SSteven Rostedt (Red Hat) * 371c4c7eb29SSteven Rostedt (Red Hat) * if (cond) 372c4c7eb29SSteven Rostedt (Red Hat) * trace_foo(); 373c4c7eb29SSteven Rostedt (Red Hat) * 374c4c7eb29SSteven Rostedt (Red Hat) * Would cause a little overhead when tracing is not enabled, and that 375c4c7eb29SSteven Rostedt (Red Hat) * overhead, even if small, is not something we want. As tracepoints 376c4c7eb29SSteven Rostedt (Red Hat) * use static branch (aka jump_labels), where no branch is taken to 377c4c7eb29SSteven Rostedt (Red Hat) * skip the tracepoint when not enabled, and a jmp is placed to jump 378c4c7eb29SSteven Rostedt (Red Hat) * to the tracepoint code when it is enabled, having a if statement 379c4c7eb29SSteven Rostedt (Red Hat) * nullifies that optimization. It would be nice to place that 380c4c7eb29SSteven Rostedt (Red Hat) * condition within the static branch. This is where TRACE_EVENT_CONDITION 381c4c7eb29SSteven Rostedt (Red Hat) * comes in. 382c4c7eb29SSteven Rostedt (Red Hat) * 383c4c7eb29SSteven Rostedt (Red Hat) * TRACE_EVENT_CONDITION() is just like TRACE_EVENT, except it adds another 384c4c7eb29SSteven Rostedt (Red Hat) * parameter just after args. Where TRACE_EVENT has: 385c4c7eb29SSteven Rostedt (Red Hat) * 386c4c7eb29SSteven Rostedt (Red Hat) * TRACE_EVENT(name, proto, args, struct, assign, printk) 387c4c7eb29SSteven Rostedt (Red Hat) * 388c4c7eb29SSteven Rostedt (Red Hat) * the CONDITION version has: 389c4c7eb29SSteven Rostedt (Red Hat) * 390c4c7eb29SSteven Rostedt (Red Hat) * TRACE_EVENT_CONDITION(name, proto, args, cond, struct, assign, printk) 391c4c7eb29SSteven Rostedt (Red Hat) * 392c4c7eb29SSteven Rostedt (Red Hat) * Everything is the same as TRACE_EVENT except for the new cond. Think 393c4c7eb29SSteven Rostedt (Red Hat) * of the cond variable as: 394c4c7eb29SSteven Rostedt (Red Hat) * 395c4c7eb29SSteven Rostedt (Red Hat) * if (cond) 396c4c7eb29SSteven Rostedt (Red Hat) * trace_foo_bar_with_cond(); 397c4c7eb29SSteven Rostedt (Red Hat) * 398c4c7eb29SSteven Rostedt (Red Hat) * Except that the logic for the if branch is placed after the static branch. 399c4c7eb29SSteven Rostedt (Red Hat) * That is, the if statement that processes the condition will not be 400c4c7eb29SSteven Rostedt (Red Hat) * executed unless that traecpoint is enabled. Otherwise it still remains 401c4c7eb29SSteven Rostedt (Red Hat) * a nop. 402c4c7eb29SSteven Rostedt (Red Hat) */ 403c4c7eb29SSteven Rostedt (Red Hat) TRACE_EVENT_CONDITION(foo_bar_with_cond, 404c4c7eb29SSteven Rostedt (Red Hat) 405c4c7eb29SSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 406c4c7eb29SSteven Rostedt (Red Hat) 407c4c7eb29SSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 408c4c7eb29SSteven Rostedt (Red Hat) 409c4c7eb29SSteven Rostedt (Red Hat) TP_CONDITION(!(bar % 10)), 410c4c7eb29SSteven Rostedt (Red Hat) 411c4c7eb29SSteven Rostedt (Red Hat) TP_STRUCT__entry( 412c4c7eb29SSteven Rostedt (Red Hat) __string( foo, foo ) 413c4c7eb29SSteven Rostedt (Red Hat) __field( int, bar ) 414c4c7eb29SSteven Rostedt (Red Hat) ), 415c4c7eb29SSteven Rostedt (Red Hat) 416c4c7eb29SSteven Rostedt (Red Hat) TP_fast_assign( 417c4c7eb29SSteven Rostedt (Red Hat) __assign_str(foo, foo); 418c4c7eb29SSteven Rostedt (Red Hat) __entry->bar = bar; 419c4c7eb29SSteven Rostedt (Red Hat) ), 420c4c7eb29SSteven Rostedt (Red Hat) 421c4c7eb29SSteven Rostedt (Red Hat) TP_printk("foo %s %d", __get_str(foo), __entry->bar) 422c4c7eb29SSteven Rostedt (Red Hat) ); 4236adc13f8SSteven Rostedt (Red Hat) 4248cf868afSSteven Rostedt (Red Hat) int foo_bar_reg(void); 4256adc13f8SSteven Rostedt (Red Hat) void foo_bar_unreg(void); 4266adc13f8SSteven Rostedt (Red Hat) 4276adc13f8SSteven Rostedt (Red Hat) /* 4286adc13f8SSteven Rostedt (Red Hat) * Now in the case that some function needs to be called when the 4296adc13f8SSteven Rostedt (Red Hat) * tracepoint is enabled and/or when it is disabled, the 4306adc13f8SSteven Rostedt (Red Hat) * TRACE_EVENT_FN() serves this purpose. This is just like TRACE_EVENT() 4316adc13f8SSteven Rostedt (Red Hat) * but adds two more parameters at the end: 4326adc13f8SSteven Rostedt (Red Hat) * 4336adc13f8SSteven Rostedt (Red Hat) * TRACE_EVENT_FN( name, proto, args, struct, assign, printk, reg, unreg) 4346adc13f8SSteven Rostedt (Red Hat) * 4356adc13f8SSteven Rostedt (Red Hat) * reg and unreg are functions with the prototype of: 4366adc13f8SSteven Rostedt (Red Hat) * 4376adc13f8SSteven Rostedt (Red Hat) * void reg(void) 4386adc13f8SSteven Rostedt (Red Hat) * 4396adc13f8SSteven Rostedt (Red Hat) * The reg function gets called before the tracepoint is enabled, and 4406adc13f8SSteven Rostedt (Red Hat) * the unreg function gets called after the tracepoint is disabled. 4416adc13f8SSteven Rostedt (Red Hat) * 4426adc13f8SSteven Rostedt (Red Hat) * Note, reg and unreg are allowed to be NULL. If you only need to 4436adc13f8SSteven Rostedt (Red Hat) * call a function before enabling, or after disabling, just set one 4446adc13f8SSteven Rostedt (Red Hat) * function and pass in NULL for the other parameter. 4456adc13f8SSteven Rostedt (Red Hat) */ 4466adc13f8SSteven Rostedt (Red Hat) TRACE_EVENT_FN(foo_bar_with_fn, 4476adc13f8SSteven Rostedt (Red Hat) 4486adc13f8SSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 4496adc13f8SSteven Rostedt (Red Hat) 4506adc13f8SSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 4516adc13f8SSteven Rostedt (Red Hat) 4526adc13f8SSteven Rostedt (Red Hat) TP_STRUCT__entry( 4536adc13f8SSteven Rostedt (Red Hat) __string( foo, foo ) 4546adc13f8SSteven Rostedt (Red Hat) __field( int, bar ) 4556adc13f8SSteven Rostedt (Red Hat) ), 4566adc13f8SSteven Rostedt (Red Hat) 4576adc13f8SSteven Rostedt (Red Hat) TP_fast_assign( 4586adc13f8SSteven Rostedt (Red Hat) __assign_str(foo, foo); 4596adc13f8SSteven Rostedt (Red Hat) __entry->bar = bar; 4606adc13f8SSteven Rostedt (Red Hat) ), 4616adc13f8SSteven Rostedt (Red Hat) 4626adc13f8SSteven Rostedt (Red Hat) TP_printk("foo %s %d", __get_str(foo), __entry->bar), 4636adc13f8SSteven Rostedt (Red Hat) 4646adc13f8SSteven Rostedt (Red Hat) foo_bar_reg, foo_bar_unreg 4656adc13f8SSteven Rostedt (Red Hat) ); 4666adc13f8SSteven Rostedt (Red Hat) 4677496946aSSteven Rostedt (Red Hat) /* 4687496946aSSteven Rostedt (Red Hat) * Each TRACE_EVENT macro creates several helper functions to produce 4697496946aSSteven Rostedt (Red Hat) * the code to add the tracepoint, create the files in the trace 4707496946aSSteven Rostedt (Red Hat) * directory, hook it to perf, assign the values and to print out 4717496946aSSteven Rostedt (Red Hat) * the raw data from the ring buffer. To prevent too much bloat, 4727496946aSSteven Rostedt (Red Hat) * if there are more than one tracepoint that uses the same format 4737496946aSSteven Rostedt (Red Hat) * for the proto, args, struct, assign and printk, and only the name 4747496946aSSteven Rostedt (Red Hat) * is different, it is highly recommended to use the DECLARE_EVENT_CLASS 4757496946aSSteven Rostedt (Red Hat) * 4767496946aSSteven Rostedt (Red Hat) * DECLARE_EVENT_CLASS() macro creates most of the functions for the 4777496946aSSteven Rostedt (Red Hat) * tracepoint. Then DEFINE_EVENT() is use to hook a tracepoint to those 4787496946aSSteven Rostedt (Red Hat) * functions. This DEFINE_EVENT() is an instance of the class and can 4797496946aSSteven Rostedt (Red Hat) * be enabled and disabled separately from other events (either TRACE_EVENT 4807496946aSSteven Rostedt (Red Hat) * or other DEFINE_EVENT()s). 4817496946aSSteven Rostedt (Red Hat) * 4827496946aSSteven Rostedt (Red Hat) * Note, TRACE_EVENT() itself is simply defined as: 4837496946aSSteven Rostedt (Red Hat) * 4847496946aSSteven Rostedt (Red Hat) * #define TRACE_EVENT(name, proto, args, tstruct, assign, printk) \ 485f094a233SWei Yang * DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, printk); \ 4867496946aSSteven Rostedt (Red Hat) * DEFINE_EVENT(name, name, proto, args) 4877496946aSSteven Rostedt (Red Hat) * 4887496946aSSteven Rostedt (Red Hat) * The DEFINE_EVENT() also can be declared with conditions and reg functions: 4897496946aSSteven Rostedt (Red Hat) * 4907496946aSSteven Rostedt (Red Hat) * DEFINE_EVENT_CONDITION(template, name, proto, args, cond); 4917496946aSSteven Rostedt (Red Hat) * DEFINE_EVENT_FN(template, name, proto, args, reg, unreg); 4927496946aSSteven Rostedt (Red Hat) */ 4937496946aSSteven Rostedt (Red Hat) DECLARE_EVENT_CLASS(foo_template, 4947496946aSSteven Rostedt (Red Hat) 4957496946aSSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 4967496946aSSteven Rostedt (Red Hat) 4977496946aSSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 4987496946aSSteven Rostedt (Red Hat) 4997496946aSSteven Rostedt (Red Hat) TP_STRUCT__entry( 5007496946aSSteven Rostedt (Red Hat) __string( foo, foo ) 5017496946aSSteven Rostedt (Red Hat) __field( int, bar ) 5027496946aSSteven Rostedt (Red Hat) ), 5037496946aSSteven Rostedt (Red Hat) 5047496946aSSteven Rostedt (Red Hat) TP_fast_assign( 5057496946aSSteven Rostedt (Red Hat) __assign_str(foo, foo); 5067496946aSSteven Rostedt (Red Hat) __entry->bar = bar; 5077496946aSSteven Rostedt (Red Hat) ), 5087496946aSSteven Rostedt (Red Hat) 5097496946aSSteven Rostedt (Red Hat) TP_printk("foo %s %d", __get_str(foo), __entry->bar) 5107496946aSSteven Rostedt (Red Hat) ); 5117496946aSSteven Rostedt (Red Hat) 5127496946aSSteven Rostedt (Red Hat) /* 5137496946aSSteven Rostedt (Red Hat) * Here's a better way for the previous samples (except, the first 51427019975SJeremy Linton * example had more fields and could not be used here). 5157496946aSSteven Rostedt (Red Hat) */ 5167496946aSSteven Rostedt (Red Hat) DEFINE_EVENT(foo_template, foo_with_template_simple, 5177496946aSSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 5187496946aSSteven Rostedt (Red Hat) TP_ARGS(foo, bar)); 5197496946aSSteven Rostedt (Red Hat) 5207496946aSSteven Rostedt (Red Hat) DEFINE_EVENT_CONDITION(foo_template, foo_with_template_cond, 5217496946aSSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 5227496946aSSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 5237496946aSSteven Rostedt (Red Hat) TP_CONDITION(!(bar % 8))); 5247496946aSSteven Rostedt (Red Hat) 5257496946aSSteven Rostedt (Red Hat) 5267496946aSSteven Rostedt (Red Hat) DEFINE_EVENT_FN(foo_template, foo_with_template_fn, 5277496946aSSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 5287496946aSSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 5297496946aSSteven Rostedt (Red Hat) foo_bar_reg, foo_bar_unreg); 5307496946aSSteven Rostedt (Red Hat) 5317496946aSSteven Rostedt (Red Hat) /* 5327496946aSSteven Rostedt (Red Hat) * Anytime two events share basically the same values and have 5337496946aSSteven Rostedt (Red Hat) * the same output, use the DECLARE_EVENT_CLASS() and DEFINE_EVENT() 5347496946aSSteven Rostedt (Red Hat) * when ever possible. 5357496946aSSteven Rostedt (Red Hat) */ 5367496946aSSteven Rostedt (Red Hat) 5377496946aSSteven Rostedt (Red Hat) /* 5387496946aSSteven Rostedt (Red Hat) * If the event is similar to the DECLARE_EVENT_CLASS, but you need 5397496946aSSteven Rostedt (Red Hat) * to have a different output, then use DEFINE_EVENT_PRINT() which 5407496946aSSteven Rostedt (Red Hat) * lets you override the TP_printk() of the class. 5417496946aSSteven Rostedt (Red Hat) */ 5427496946aSSteven Rostedt (Red Hat) 5437496946aSSteven Rostedt (Red Hat) DEFINE_EVENT_PRINT(foo_template, foo_with_template_print, 5447496946aSSteven Rostedt (Red Hat) TP_PROTO(const char *foo, int bar), 5457496946aSSteven Rostedt (Red Hat) TP_ARGS(foo, bar), 5467496946aSSteven Rostedt (Red Hat) TP_printk("bar %s %d", __get_str(foo), __entry->bar)); 5477496946aSSteven Rostedt (Red Hat) 548b466b133SMasami Hiramatsu /* 549b466b133SMasami Hiramatsu * There are yet another __rel_loc dynamic data attribute. If you 550b466b133SMasami Hiramatsu * use __rel_dynamic_array() and __rel_string() etc. macros, you 551b466b133SMasami Hiramatsu * can use this attribute. There is no difference from the viewpoint 552b466b133SMasami Hiramatsu * of functionality with/without 'rel' but the encoding is a bit 553b466b133SMasami Hiramatsu * different. This is expected to be used with user-space event, 554b466b133SMasami Hiramatsu * there is no reason that the kernel event use this, but only for 555b466b133SMasami Hiramatsu * testing. 556b466b133SMasami Hiramatsu */ 557b466b133SMasami Hiramatsu 558b466b133SMasami Hiramatsu TRACE_EVENT(foo_rel_loc, 559b466b133SMasami Hiramatsu 560*8230f27bSSteven Rostedt (Google) TP_PROTO(const char *foo, int bar, unsigned long *mask, const cpumask_t *cpus), 561b466b133SMasami Hiramatsu 562*8230f27bSSteven Rostedt (Google) TP_ARGS(foo, bar, mask, cpus), 563b466b133SMasami Hiramatsu 564b466b133SMasami Hiramatsu TP_STRUCT__entry( 565b466b133SMasami Hiramatsu __rel_string( foo, foo ) 566b466b133SMasami Hiramatsu __field( int, bar ) 567b466b133SMasami Hiramatsu __rel_bitmask( bitmask, 568b466b133SMasami Hiramatsu BITS_PER_BYTE * sizeof(unsigned long) ) 569*8230f27bSSteven Rostedt (Google) __rel_cpumask( cpumask ) 570b466b133SMasami Hiramatsu ), 571b466b133SMasami Hiramatsu 572b466b133SMasami Hiramatsu TP_fast_assign( 573b466b133SMasami Hiramatsu __assign_rel_str(foo, foo); 574b466b133SMasami Hiramatsu __entry->bar = bar; 575b466b133SMasami Hiramatsu __assign_rel_bitmask(bitmask, mask, 576b466b133SMasami Hiramatsu BITS_PER_BYTE * sizeof(unsigned long)); 577*8230f27bSSteven Rostedt (Google) __assign_rel_cpumask(cpumask, cpus); 578b466b133SMasami Hiramatsu ), 579b466b133SMasami Hiramatsu 580*8230f27bSSteven Rostedt (Google) TP_printk("foo_rel_loc %s, %d, %s, %s", __get_rel_str(foo), __entry->bar, 581*8230f27bSSteven Rostedt (Google) __get_rel_bitmask(bitmask), 582*8230f27bSSteven Rostedt (Google) __get_rel_cpumask(cpumask)) 583b466b133SMasami Hiramatsu ); 5849cfe06f8SSteven Rostedt #endif 5859cfe06f8SSteven Rostedt 5869cfe06f8SSteven Rostedt /***** NOTICE! The #if protection ends here. *****/ 5879cfe06f8SSteven Rostedt 5889cfe06f8SSteven Rostedt 5899cfe06f8SSteven Rostedt /* 5909cfe06f8SSteven Rostedt * There are several ways I could have done this. If I left out the 5919cfe06f8SSteven Rostedt * TRACE_INCLUDE_PATH, then it would default to the kernel source 5929cfe06f8SSteven Rostedt * include/trace/events directory. 5939cfe06f8SSteven Rostedt * 5949cfe06f8SSteven Rostedt * I could specify a path from the define_trace.h file back to this 5959cfe06f8SSteven Rostedt * file. 5969cfe06f8SSteven Rostedt * 5979cfe06f8SSteven Rostedt * #define TRACE_INCLUDE_PATH ../../samples/trace_events 5989cfe06f8SSteven Rostedt * 59944ad18e0SSteven Rostedt * But the safest and easiest way to simply make it use the directory 60044ad18e0SSteven Rostedt * that the file is in is to add in the Makefile: 6019cfe06f8SSteven Rostedt * 60244ad18e0SSteven Rostedt * CFLAGS_trace-events-sample.o := -I$(src) 6039cfe06f8SSteven Rostedt * 6049cfe06f8SSteven Rostedt * This will make sure the current path is part of the include 60544ad18e0SSteven Rostedt * structure for our file so that define_trace.h can find it. 6069cfe06f8SSteven Rostedt * 6079cfe06f8SSteven Rostedt * I could have made only the top level directory the include: 6089cfe06f8SSteven Rostedt * 6099cfe06f8SSteven Rostedt * CFLAGS_trace-events-sample.o := -I$(PWD) 6109cfe06f8SSteven Rostedt * 6119cfe06f8SSteven Rostedt * And then let the path to this directory be the TRACE_INCLUDE_PATH: 6129cfe06f8SSteven Rostedt * 6139cfe06f8SSteven Rostedt * #define TRACE_INCLUDE_PATH samples/trace_events 6149cfe06f8SSteven Rostedt * 61544ad18e0SSteven Rostedt * But then if something defines "samples" or "trace_events" as a macro 61644ad18e0SSteven Rostedt * then we could risk that being converted too, and give us an unexpected 6179cfe06f8SSteven Rostedt * result. 6189cfe06f8SSteven Rostedt */ 6199cfe06f8SSteven Rostedt #undef TRACE_INCLUDE_PATH 62071e1c8acSSteven Rostedt #undef TRACE_INCLUDE_FILE 6219cfe06f8SSteven Rostedt #define TRACE_INCLUDE_PATH . 62271e1c8acSSteven Rostedt /* 62371e1c8acSSteven Rostedt * TRACE_INCLUDE_FILE is not needed if the filename and TRACE_SYSTEM are equal 62471e1c8acSSteven Rostedt */ 62571e1c8acSSteven Rostedt #define TRACE_INCLUDE_FILE trace-events-sample 6269cfe06f8SSteven Rostedt #include <trace/define_trace.h> 627