linux/include/trace/syscall.h

#ifndef _TRACE_SYSCALL_H
#define _TRACE_SYSCALL_H

#include <linux/tracepoint.h>

#include <asm/ptrace.h>


extern void syscall_regfunc(void);
extern void syscall_unregfunc(void);

DECLARE_TRACE_WITH_CALLBACK(syscall_enter,
	TP_PROTO(struct pt_regs *regs, long id),
	TP_ARGS(regs, id),
	syscall_regfunc,
	syscall_unregfunc
);

DECLARE_TRACE_WITH_CALLBACK(syscall_exit,
	TP_PROTO(struct pt_regs *regs, long ret),
	TP_ARGS(regs, ret),
	syscall_regfunc,
	syscall_unregfunc
);

/*
 * A syscall entry in the ftrace syscalls array.
 *
 * @name: name of the syscall
 * @nb_args: number of parameters it takes
 * @types: list of types as strings
 * @args: list of args as strings (args[i] matches types[i])
 */
struct syscall_metadata {
	const char	*name;
	int		nb_args;
	const char	**types;
	const char	**args;
};

#ifdef CONFIG_FTRACE_SYSCALLS
extern struct syscall_metadata *syscall_nr_to_meta(int nr);
extern void start_ftrace_syscalls(void);
extern void stop_ftrace_syscalls(void);
extern void ftrace_syscall_enter(struct pt_regs *regs);
extern void ftrace_syscall_exit(struct pt_regs *regs);
#else
static inline void start_ftrace_syscalls(void)			{ }
static inline void stop_ftrace_syscalls(void)			{ }
static inline void ftrace_syscall_enter(struct pt_regs *regs)	{ }
static inline void ftrace_syscall_exit(struct pt_regs *regs)	{ }
#endif

#endif /* _TRACE_SYSCALL_H */