linux_dsm_epyc7002/arch/arm64/include/asm/ftrace.h
AKASHI Takahiro 055b1212d1 arm64: ftrace: Add system call tracepoint
This patch allows system call entry or exit to be traced as ftrace events,
ie. sys_enter_*/sys_exit_*, if CONFIG_FTRACE_SYSCALLS is enabled.
Those events appear and can be controlled under
    ${sysfs}/tracing/events/syscalls/

Please note that we can't trace compat system calls here because
AArch32 mode does not share the same syscall table with AArch64.
Just define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS in order to avoid unexpected
results (bogus syscalls reported or even hang-up).

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-05-29 09:08:33 +01:00

60 lines
1.5 KiB
C

/*
* arch/arm64/include/asm/ftrace.h
*
* Copyright (C) 2013 Linaro Limited
* Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_FTRACE_H
#define __ASM_FTRACE_H
#include <asm/insn.h>
#define MCOUNT_ADDR ((unsigned long)_mcount)
#define MCOUNT_INSN_SIZE AARCH64_INSN_SIZE
#ifndef __ASSEMBLY__
#include <linux/compat.h>
extern void _mcount(unsigned long);
extern void *return_address(unsigned int);
struct dyn_arch_ftrace {
/* No extra data needed for arm64 */
};
extern unsigned long ftrace_graph_call;
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
/*
* addr is the address of the mcount call instruction.
* recordmcount does the necessary offset calculation.
*/
return addr;
}
#define ftrace_return_address(n) return_address(n)
/*
* Because AArch32 mode does not share the same syscall table with AArch64,
* tracing compat syscalls may result in reporting bogus syscalls or even
* hang-up, so just do not trace them.
* See kernel/trace/trace_syscalls.c
*
* x86 code says:
* If the user realy wants these, then they should use the
* raw syscall tracepoints with filtering.
*/
#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
{
return is_compat_task();
}
#endif /* ifndef __ASSEMBLY__ */
#endif /* __ASM_FTRACE_H */