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