Viewing file:  tracepoint-defs.h (2.36 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef TRACEPOINT_DEFS_H
#define TRACEPOINT_DEFS_H 1
/*
* File can be included directly by headers who only want to access
* tracepoint->key to guard out of line trace calls, or the definition of
* trace_print_flags{_u64}. Otherwise linux/tracepoint.h should be used.
*/
#include <linux/atomic.h>
#include <linux/static_key.h>
struct static_call_key;
struct trace_print_flags {
unsigned long mask;
const char *name;
};
struct trace_print_flags_u64 {
unsigned long long mask;
const char *name;
};
struct tracepoint_func {
void *func;
void *data;
int prio;
};
struct tracepoint {
const char *name; /* Tracepoint name */
struct static_key key;
struct static_call_key *static_call_key;
void *static_call_tramp;
void *iterator;
void *probestub;
int (*regfunc)(void);
void (*unregfunc)(void);
struct tracepoint_func __rcu *funcs;
};
#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
typedef const int tracepoint_ptr_t;
#else
typedef struct tracepoint * const tracepoint_ptr_t;
#endif
struct bpf_raw_event_map {
struct tracepoint *tp;
void *bpf_func;
u32 num_args;
u32 writable_size;
} __aligned(32);
/*
* If a tracepoint needs to be called from a header file, it is not
* recommended to call it directly, as tracepoints in header files
* may cause side-effects and bloat the kernel. Instead, use
* tracepoint_enabled() to test if the tracepoint is enabled, then if
* it is, call a wrapper function defined in a C file that will then
* call the tracepoint.
*
* For "trace_foo_bar()", you would need to create a wrapper function
* in a C file to call trace_foo_bar():
* void do_trace_foo_bar(args) { trace_foo_bar(args); }
* Then in the header file, declare the tracepoint:
* DECLARE_TRACEPOINT(foo_bar);
* And call your wrapper:
* static inline void some_inlined_function() {
* [..]
* if (tracepoint_enabled(foo_bar))
* do_trace_foo_bar(args);
* [..]
* }
*
* Note: tracepoint_enabled(foo_bar) is equivalent to trace_foo_bar_enabled()
* but is safe to have in headers, where trace_foo_bar_enabled() is not.
*/
#define DECLARE_TRACEPOINT(tp) \
extern struct tracepoint __tracepoint_##tp
#ifdef CONFIG_TRACEPOINTS
# define tracepoint_enabled(tp) \
static_key_false(&(__tracepoint_##tp).key)
#else
# define tracepoint_enabled(tracepoint) false
#endif
#endif
|