diff options
author | Ingo Molnar <mingo@kernel.org> | 2019-12-10 10:11:00 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2019-12-10 10:11:00 +0100 |
commit | 2040cf9f59037aa8aec749363e69ead165b67b43 (patch) | |
tree | e9c15448e841cc493bc80b9f658d7955623e86dd /samples/ftrace/sample-trace-array.h | |
parent | f66c0447cca1281116224d474cdb37d6a18e4b5b (diff) | |
parent | e42617b825f8073569da76dc4510bfa019b1c35a (diff) |
Merge tag 'v5.5-rc1' into core/kprobes, to resolve conflicts
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'samples/ftrace/sample-trace-array.h')
-rw-r--r-- | samples/ftrace/sample-trace-array.h | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/samples/ftrace/sample-trace-array.h b/samples/ftrace/sample-trace-array.h new file mode 100644 index 0000000000000..6f89624281585 --- /dev/null +++ b/samples/ftrace/sample-trace-array.h @@ -0,0 +1,84 @@ +/* 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> |