linux/arch/x86/include/asm/ftrace.h
Steven Rostedt (Red Hat) 1026ff9b8e ftrace/x86: Have function graph tracer use its own trampoline
The function graph trampoline is called from the function trampoline
and both do a save and restore of registers. The save of registers
done by the function trampoline when only the function graph tracer
is running is a waste of CPU cycles.

As the function graph tracer trampoline in x86 is dependent from
the function trampoline, we can call it directly when a function
is only being traced by the function graph trampoline.

Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-07-17 09:44:37 -04:00

102 lines
2.3 KiB
C

#ifndef _ASM_X86_FTRACE_H
#define _ASM_X86_FTRACE_H
#ifdef __ASSEMBLY__
/* skip is set if the stack was already partially adjusted */
.macro MCOUNT_SAVE_FRAME skip=0
/*
* We add enough stack to save all regs.
*/
subq $(SS+8-\skip), %rsp
movq %rax, RAX(%rsp)
movq %rcx, RCX(%rsp)
movq %rdx, RDX(%rsp)
movq %rsi, RSI(%rsp)
movq %rdi, RDI(%rsp)
movq %r8, R8(%rsp)
movq %r9, R9(%rsp)
/* Move RIP to its proper location */
movq SS+8(%rsp), %rdx
movq %rdx, RIP(%rsp)
.endm
.macro MCOUNT_RESTORE_FRAME skip=0
movq R9(%rsp), %r9
movq R8(%rsp), %r8
movq RDI(%rsp), %rdi
movq RSI(%rsp), %rsi
movq RDX(%rsp), %rdx
movq RCX(%rsp), %rcx
movq RAX(%rsp), %rax
addq $(SS+8-\skip), %rsp
.endm
#endif
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CC_USING_FENTRY
# define MCOUNT_ADDR ((long)(__fentry__))
#else
# define MCOUNT_ADDR ((long)(mcount))
#endif
#define MCOUNT_INSN_SIZE 5 /* sizeof mcount call */
#ifdef CONFIG_DYNAMIC_FTRACE
#define ARCH_SUPPORTS_FTRACE_OPS 1
#endif
#ifndef __ASSEMBLY__
extern void mcount(void);
extern atomic_t modifying_ftrace_code;
extern void __fentry__(void);
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;
}
#ifdef CONFIG_DYNAMIC_FTRACE
struct dyn_arch_ftrace {
/* No extra data needed for x86 */
};
int ftrace_int3_handler(struct pt_regs *regs);
#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_FUNCTION_TRACER */
#if !defined(__ASSEMBLY__) && !defined(COMPILE_OFFSETS)
#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION)
#include <asm/compat.h>
/*
* Because ia32 syscalls do not map to x86_64 syscall numbers
* this screws up the trace output when tracing a ia32 task.
* Instead of reporting bogus syscalls, just do not trace them.
*
* If the user realy wants these, then they should use the
* raw syscall tracepoints with filtering.
*/
#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1
static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
{
if (is_compat_task())
return true;
return false;
}
#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */
#endif /* !__ASSEMBLY__ && !COMPILE_OFFSETS */
#endif /* _ASM_X86_FTRACE_H */