linux/arch/powerpc/include/asm/ftrace.h
Ian Munsie 02424d8966 powerpc/ftrace: Implement raw syscall tracepoints on PowerPC
This patch implements the raw syscall tracepoints on PowerPC and exports
them for ftrace syscalls to use.

To minimise reworking existing code, I slightly re-ordered the thread
info flags such that the new TIF_SYSCALL_TRACEPOINT bit would still fit
within the 16 bits of the andi. instruction's UI field. The instructions
in question are in /arch/powerpc/kernel/entry_{32,64}.S to and the
_TIF_SYSCALL_T_OR_A with the thread flags to see if system call tracing
is enabled.

In the case of 64bit PowerPC, arch_syscall_addr and
arch_syscall_match_sym_name are overridden to allow ftrace syscalls to
work given the unusual system call table structure and symbol names that
start with a period.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:57 +10:00

78 lines
1.9 KiB
C

#ifndef _ASM_POWERPC_FTRACE
#define _ASM_POWERPC_FTRACE
#ifdef CONFIG_FUNCTION_TRACER
#define MCOUNT_ADDR ((long)(_mcount))
#define MCOUNT_INSN_SIZE 4 /* sizeof mcount call */
#ifdef __ASSEMBLY__
/* Based off of objdump optput from glibc */
#define MCOUNT_SAVE_FRAME \
stwu r1,-48(r1); \
stw r3, 12(r1); \
stw r4, 16(r1); \
stw r5, 20(r1); \
stw r6, 24(r1); \
mflr r3; \
lwz r4, 52(r1); \
mfcr r5; \
stw r7, 28(r1); \
stw r8, 32(r1); \
stw r9, 36(r1); \
stw r10,40(r1); \
stw r3, 44(r1); \
stw r5, 8(r1)
#define MCOUNT_RESTORE_FRAME \
lwz r6, 8(r1); \
lwz r0, 44(r1); \
lwz r3, 12(r1); \
mtctr r0; \
lwz r4, 16(r1); \
mtcr r6; \
lwz r5, 20(r1); \
lwz r6, 24(r1); \
lwz r0, 52(r1); \
lwz r7, 28(r1); \
lwz r8, 32(r1); \
mtlr r0; \
lwz r9, 36(r1); \
lwz r10,40(r1); \
addi r1, r1, 48
#else /* !__ASSEMBLY__ */
extern void _mcount(void);
#ifdef CONFIG_DYNAMIC_FTRACE
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
/* reloction of mcount call site is the same as the address */
return addr;
}
struct dyn_arch_ftrace {
struct module *mod;
};
#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* __ASSEMBLY__ */
#endif
#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_PPC64) && !defined(__ASSEMBLY__)
#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
{
/*
* Compare the symbol name with the system call name. Skip the .sys or .SyS
* prefix from the symbol name and the sys prefix from the system call name and
* just match the rest. This is only needed on ppc64 since symbol names on
* 32bit do not start with a period so the generic function will work.
*/
return !strcmp(sym + 4, name + 3);
}
#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_PPC64 && !__ASSEMBLY__ */
#endif /* _ASM_POWERPC_FTRACE */