/* SPDX-License-Identifier: GPL-2.0 */ /* * If TRACE_SYSTEM is defined, that will be the directory created * in the ftrace directory under /sys/kernel/tracing/events/<system> * * 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-trace.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 sample-trace-array.h but we want the system * to be called "sample-subsystem". Therefore we must define the name of this * file: * * #define TRACE_INCLUDE_FILE sample-trace-array * * As we do in 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 sample-subsystem /* * TRACE_SYSTEM is expected to be a C valid variable (alpha-numeric * and underscore), although it may start with numbers. If for some * reason it is not, you need to add the following lines: */ #undef TRACE_SYSTEM_VAR #define TRACE_SYSTEM_VAR sample_subsystem /* * But the above is only needed if TRACE_SYSTEM is not alpha-numeric * and underscored. By default, TRACE_SYSTEM_VAR will be equal to * TRACE_SYSTEM. As TRACE_SYSTEM_VAR must be alpha-numeric, if * TRACE_SYSTEM is not, then TRACE_SYSTEM_VAR must be defined with * only alpha-numeric and underscores. * * The TRACE_SYSTEM_VAR is only used internally and not visible to * user space. */ /* * 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(_SAMPLE_TRACE_ARRAY_H) || defined(TRACE_HEADER_MULTI_READ) #define _SAMPLE_TRACE_ARRAY_H #include <linux/tracepoint.h> TRACE_EVENT(sample_event, TP_PROTO(int count, unsigned long time), TP_ARGS(count, time), TP_STRUCT__entry( __field(int, count) __field(unsigned long, time) ), TP_fast_assign( __entry->count = count; __entry->time = time; ), TP_printk("count value=%d at jiffies=%lu", __entry->count, __entry->time) ); #endif #undef TRACE_INCLUDE_PATH #define TRACE_INCLUDE_PATH . #define TRACE_INCLUDE_FILE sample-trace-array #include <trace/define_trace.h>