From 02424d8966d803e33cbe51469be56b5d177b4a37 Mon Sep 17 00:00:00 2001 From: Ian Munsie Date: Wed, 2 Feb 2011 17:27:24 +0000 Subject: 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/ftrace.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'arch/powerpc/include/asm/ftrace.h') diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index dde1296b8b4..169d039ed40 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -60,4 +60,18 @@ struct dyn_arch_ftrace { #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 */ -- cgit v1.2.3-70-g09d2