Message ID | c78366416ce93f704ae7000c4ee60eb4258c38f7.1680954589.git.pengdonglin@sangfor.com.cn (mailing list archive) |
---|---|
State | Accepted |
Commit | 3646970322464c21e69dcb9a2e37d461c5834bf5 |
Headers | show |
Series | function_graph: Support recording and printing the return value of function | expand |
On Sat, Apr 08, 2023 at 05:42:18AM -0700, Donglin Peng wrote: > The previous patch ("function_graph: Support recording and printing > the return value of function") has laid the groundwork for the for > the funcgraph-retval, and this modification makes it available on > the ARM64 platform. > > We introduce a new structure called fgraph_ret_regs for the ARM64 > platform to hold return registers and the frame pointer. We then > fill its content in the return_to_handler and pass its address to > the function ftrace_return_to_handler to record the return value. > > Reviewed-by: Mark Rutland <mark.rutland@arm.com> > Tested-by: Mark Rutland <mark.rutland@arm.com> > Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn> We fully trust Mark's reviews ;) but just in case you need an official maintainer ack: Acked-by: Catalin Marinas <catalin.marinas@arm.com>
On Fri, 9 Jun 2023 10:31:19 +0100 Catalin Marinas <catalin.marinas@arm.com> wrote: > On Sat, Apr 08, 2023 at 05:42:18AM -0700, Donglin Peng wrote: > > The previous patch ("function_graph: Support recording and printing > > the return value of function") has laid the groundwork for the for > > the funcgraph-retval, and this modification makes it available on > > the ARM64 platform. > > > > We introduce a new structure called fgraph_ret_regs for the ARM64 > > platform to hold return registers and the frame pointer. We then > > fill its content in the return_to_handler and pass its address to > > the function ftrace_return_to_handler to record the return value. > > > > Reviewed-by: Mark Rutland <mark.rutland@arm.com> > > Tested-by: Mark Rutland <mark.rutland@arm.com> > > Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn> > > We fully trust Mark's reviews ;) but just in case you need an official > maintainer ack: > > Acked-by: Catalin Marinas <catalin.marinas@arm.com> Thanks Catalin, that does help. -- Steve
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1023e896d46b..48856d230800 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -195,6 +195,7 @@ config ARM64 select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER select HAVE_FUNCTION_ERROR_INJECTION + select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 1c2672bbbf37..657adcbd80a4 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -170,4 +170,26 @@ static inline bool arch_syscall_match_sym_name(const char *sym, } #endif /* ifndef __ASSEMBLY__ */ +#ifndef __ASSEMBLY__ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +struct fgraph_ret_regs { + /* x0 - x7 */ + unsigned long regs[8]; + + unsigned long fp; + unsigned long __unused; +}; + +static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) +{ + return ret_regs->regs[0]; +} + +static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) +{ + return ret_regs->fp; +} +#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ +#endif + #endif /* __ASM_FTRACE_H */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index ae345b06e9f7..75082e0409bf 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -197,6 +197,19 @@ int main(void) #endif #ifdef CONFIG_FUNCTION_TRACER DEFINE(FTRACE_OPS_FUNC, offsetof(struct ftrace_ops, func)); +#endif + BLANK(); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + DEFINE(FGRET_REGS_X0, offsetof(struct fgraph_ret_regs, regs[0])); + DEFINE(FGRET_REGS_X1, offsetof(struct fgraph_ret_regs, regs[1])); + DEFINE(FGRET_REGS_X2, offsetof(struct fgraph_ret_regs, regs[2])); + DEFINE(FGRET_REGS_X3, offsetof(struct fgraph_ret_regs, regs[3])); + DEFINE(FGRET_REGS_X4, offsetof(struct fgraph_ret_regs, regs[4])); + DEFINE(FGRET_REGS_X5, offsetof(struct fgraph_ret_regs, regs[5])); + DEFINE(FGRET_REGS_X6, offsetof(struct fgraph_ret_regs, regs[6])); + DEFINE(FGRET_REGS_X7, offsetof(struct fgraph_ret_regs, regs[7])); + DEFINE(FGRET_REGS_FP, offsetof(struct fgraph_ret_regs, fp)); + DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs)); #endif return 0; } diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S index 350ed81324ac..da1443bcf776 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -270,22 +270,23 @@ SYM_FUNC_END(ftrace_stub_graph) */ SYM_CODE_START(return_to_handler) /* save return value regs */ - sub sp, sp, #64 - stp x0, x1, [sp] - stp x2, x3, [sp, #16] - stp x4, x5, [sp, #32] - stp x6, x7, [sp, #48] + sub sp, sp, #FGRET_REGS_SIZE + stp x0, x1, [sp, #FGRET_REGS_X0] + stp x2, x3, [sp, #FGRET_REGS_X2] + stp x4, x5, [sp, #FGRET_REGS_X4] + stp x6, x7, [sp, #FGRET_REGS_X6] + str x29, [sp, #FGRET_REGS_FP] // parent's fp - mov x0, x29 // parent's fp - bl ftrace_return_to_handler// addr = ftrace_return_to_hander(fp); - mov x30, x0 // restore the original return address + mov x0, sp + bl ftrace_return_to_handler // addr = ftrace_return_to_hander(regs); + mov x30, x0 // restore the original return address /* restore return value regs */ - ldp x0, x1, [sp] - ldp x2, x3, [sp, #16] - ldp x4, x5, [sp, #32] - ldp x6, x7, [sp, #48] - add sp, sp, #64 + ldp x0, x1, [sp, #FGRET_REGS_X0] + ldp x2, x3, [sp, #FGRET_REGS_X2] + ldp x4, x5, [sp, #FGRET_REGS_X4] + ldp x6, x7, [sp, #FGRET_REGS_X6] + add sp, sp, #FGRET_REGS_SIZE ret SYM_CODE_END(return_to_handler)