alistair23-linux/include/linux/tracepoint-defs.h
Linus Torvalds fefa636d81 Updates for tracing and bootconfig:
- Add support for "bool" type in synthetic events
 
 - Add per instance tracing for bootconfig
 
 - Support perf-style return probe ("SYMBOL%return") in kprobes and uprobes
 
 - Allow for kprobes to be enabled earlier in boot up
 
 - Added tracepoint helper function to allow testing if tracepoints are
   enabled in headers
 
 - Synthetic events can now have dynamic strings (variable length)
 
 - Various fixes and cleanups
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Merge tag 'trace-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Updates for tracing and bootconfig:

   - Add support for "bool" type in synthetic events

   - Add per instance tracing for bootconfig

   - Support perf-style return probe ("SYMBOL%return") in kprobes and
     uprobes

   - Allow for kprobes to be enabled earlier in boot up

   - Added tracepoint helper function to allow testing if tracepoints
     are enabled in headers

   - Synthetic events can now have dynamic strings (variable length)

   - Various fixes and cleanups"

* tag 'trace-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (58 commits)
  tracing: support "bool" type in synthetic trace events
  selftests/ftrace: Add test case for synthetic event syntax errors
  tracing: Handle synthetic event array field type checking correctly
  selftests/ftrace: Change synthetic event name for inter-event-combined test
  tracing: Add synthetic event error logging
  tracing: Check that the synthetic event and field names are legal
  tracing: Move is_good_name() from trace_probe.h to trace.h
  tracing: Don't show dynamic string internals in synthetic event description
  tracing: Fix some typos in comments
  tracing/boot: Add ftrace.instance.*.alloc_snapshot option
  tracing: Fix race in trace_open and buffer resize call
  tracing: Check return value of __create_val_fields() before using its result
  tracing: Fix synthetic print fmt check for use of __get_str()
  tracing: Remove a pointless assignment
  ftrace: ftrace_global_list is renamed to ftrace_ops_list
  ftrace: Format variable declarations of ftrace_allocate_records
  ftrace: Simplify the calculation of page number for ftrace_page->records
  ftrace: Simplify the dyn_ftrace->flags macro
  ftrace: Simplify the hash calculation
  ftrace: Use fls() to get the bits for dup_hash()
  ...
2020-10-15 15:51:28 -07:00

91 lines
2.3 KiB
C

/* 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;
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