name : tracepoint-defs.h /* 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