diff options
Diffstat (limited to 'Documentation/trace/tracepoints.txt')
| -rw-r--r-- | Documentation/trace/tracepoints.txt | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/Documentation/trace/tracepoints.txt b/Documentation/trace/tracepoints.txt index da49437d5ae..ac4170dd0f2 100644 --- a/Documentation/trace/tracepoints.txt +++ b/Documentation/trace/tracepoints.txt @@ -40,7 +40,13 @@ Two elements are required for tracepoints : In order to use tracepoints, you should include linux/tracepoint.h. -In include/trace/subsys.h : +In include/trace/events/subsys.h : + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM subsys + +#if !defined(_TRACE_SUBSYS_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_SUBSYS_H #include <linux/tracepoint.h> @@ -48,10 +54,16 @@ DECLARE_TRACE(subsys_eventname, TP_PROTO(int firstarg, struct task_struct *p), TP_ARGS(firstarg, p)); +#endif /* _TRACE_SUBSYS_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> + In subsys/file.c (where the tracing statement must be added) : -#include <trace/subsys.h> +#include <trace/events/subsys.h> +#define CREATE_TRACE_POINTS DEFINE_TRACE(subsys_eventname); void somefct(void) @@ -72,6 +84,9 @@ Where : - TP_ARGS(firstarg, p) are the parameters names, same as found in the prototype. +- if you use the header in multiple source files, #define CREATE_TRACE_POINTS + should appear only in one source file. + Connecting a function (probe) to a tracepoint is done by providing a probe (function to call) for the specific tracepoint through register_trace_subsys_eventname(). Removing a probe is done through |