| Message ID | 20220224093251.49971-3-zhouchengming@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/3] ftrace: cleanup ftrace_graph_caller enable and disable | expand |
Hello, ping... have any comments? Thanks. On 2022/2/24 5:32 下午, Chengming Zhou wrote: > As we do in commit 0c0593b45c9b ("x86/ftrace: Make function graph > use ftrace directly"), we don't need special hook for graph tracer, > but instead we use graph_ops:func function to install return_hooker. > > Since commit 3b23e4991fb6 ("arm64: implement ftrace with regs") add > implementation for FTRACE_WITH_REGS on arm64, we can easily adopt > the same cleanup on arm64. And this cleanup only changes the > FTRACE_WITH_REGS implementation, so the mcount-based implementation > is unaffected. > > Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> > --- > Changes in v3: > - Add comments in ftrace_graph_func() as suggested by Steve. > > Changes in v2: > - Remove FTRACE_WITH_REGS ftrace_graph_caller asm as suggested by Mark. > --- > arch/arm64/include/asm/ftrace.h | 7 +++++++ > arch/arm64/kernel/entry-ftrace.S | 17 ----------------- > arch/arm64/kernel/ftrace.c | 17 +++++++++++++++++ > 3 files changed, 24 insertions(+), 17 deletions(-) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index 1494cfa8639b..dbc45a4157fa 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -80,8 +80,15 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) > > #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > struct dyn_ftrace; > +struct ftrace_ops; > +struct ftrace_regs; > + > int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); > #define ftrace_init_nop ftrace_init_nop > + > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs); > +#define ftrace_graph_func ftrace_graph_func > #endif > > #define ftrace_return_address(n) return_address(n) > diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S > index e535480a4069..d42a205ef625 100644 > --- a/arch/arm64/kernel/entry-ftrace.S > +++ b/arch/arm64/kernel/entry-ftrace.S > @@ -97,12 +97,6 @@ SYM_CODE_START(ftrace_common) > SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) > bl ftrace_stub > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller(); > - nop // If enabled, this will be replaced > - // "b ftrace_graph_caller" > -#endif > - > /* > * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved > * x19-x29 per the AAPCS, and we created frame records upon entry, so we need > @@ -127,17 +121,6 @@ ftrace_common_return: > ret x9 > SYM_CODE_END(ftrace_common) > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > -SYM_CODE_START(ftrace_graph_caller) > - ldr x0, [sp, #S_PC] > - sub x0, x0, #AARCH64_INSN_SIZE // ip (callsite's BL insn) > - add x1, sp, #S_LR // parent_ip (callsite's LR) > - ldr x2, [sp, #PT_REGS_SIZE] // parent fp (callsite's FP) > - bl prepare_ftrace_return > - b ftrace_common_return > -SYM_CODE_END(ftrace_graph_caller) > -#endif > - > #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > > /* > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c > index 4506c4a90ac1..35eb7c9b5e53 100644 > --- a/arch/arm64/kernel/ftrace.c > +++ b/arch/arm64/kernel/ftrace.c > @@ -268,6 +268,22 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, > } > > #ifdef CONFIG_DYNAMIC_FTRACE > + > +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs) > +{ > + /* > + * Athough graph_ops doesn't have FTRACE_OPS_FL_SAVE_REGS set in flags, > + * regs can't be NULL in DYNAMIC_FTRACE_WITH_REGS. By design, it should > + * be fixed when DYNAMIC_FTRACE_WITH_ARGS is implemented. > + */ > + struct pt_regs *regs = arch_ftrace_get_regs(fregs); > + unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); > + > + prepare_ftrace_return(ip, parent, frame_pointer(regs)); > +} > +#else > /* > * Turn on/off the call to ftrace_graph_caller() in ftrace_caller() > * depending on @enable. > @@ -297,5 +313,6 @@ int ftrace_disable_ftrace_graph_caller(void) > { > return ftrace_modify_graph_caller(false); > } > +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > #endif /* CONFIG_DYNAMIC_FTRACE */ > #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
On Tue, 22 Mar 2022 20:48:00 +0800 Chengming Zhou <zhouchengming@bytedance.com> wrote: > Hello, > > ping... have any comments? Hi Chengming, BTW, if you don't hear back for a week, it's OK to send a ping. You don't need to wait a month. Usually, it's just that the maintainers have other priorities and will try to look at it when they get a chance, but then forget to do so :-/ > > Thanks. > > On 2022/2/24 5:32 下午, Chengming Zhou wrote: > > As we do in commit 0c0593b45c9b ("x86/ftrace: Make function graph > > use ftrace directly"), we don't need special hook for graph tracer, > > but instead we use graph_ops:func function to install return_hooker. > > > > Since commit 3b23e4991fb6 ("arm64: implement ftrace with regs") add > > implementation for FTRACE_WITH_REGS on arm64, we can easily adopt > > the same cleanup on arm64. And this cleanup only changes the > > FTRACE_WITH_REGS implementation, so the mcount-based implementation > > is unaffected. > > > > Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> > > --- > > Changes in v3: > > - Add comments in ftrace_graph_func() as suggested by Steve. > > > > Changes in v2: > > - Remove FTRACE_WITH_REGS ftrace_graph_caller asm as suggested by Mark. > > --- > > arch/arm64/include/asm/ftrace.h | 7 +++++++ > > arch/arm64/kernel/entry-ftrace.S | 17 ----------------- > > arch/arm64/kernel/ftrace.c | 17 +++++++++++++++++ > > 3 files changed, 24 insertions(+), 17 deletions(-) > > > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > > index 1494cfa8639b..dbc45a4157fa 100644 > > --- a/arch/arm64/include/asm/ftrace.h > > +++ b/arch/arm64/include/asm/ftrace.h > > @@ -80,8 +80,15 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) > > > > #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > > struct dyn_ftrace; > > +struct ftrace_ops; > > +struct ftrace_regs; > > + > > int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); > > #define ftrace_init_nop ftrace_init_nop > > + > > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > > + struct ftrace_ops *op, struct ftrace_regs *fregs); > > +#define ftrace_graph_func ftrace_graph_func > > #endif > > > > #define ftrace_return_address(n) return_address(n) > > diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S > > index e535480a4069..d42a205ef625 100644 > > --- a/arch/arm64/kernel/entry-ftrace.S > > +++ b/arch/arm64/kernel/entry-ftrace.S > > @@ -97,12 +97,6 @@ SYM_CODE_START(ftrace_common) > > SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) > > bl ftrace_stub > > > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > > -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller(); > > - nop // If enabled, this will be replaced > > - // "b ftrace_graph_caller" > > -#endif > > - > > /* > > * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved > > * x19-x29 per the AAPCS, and we created frame records upon entry, so we need > > @@ -127,17 +121,6 @@ ftrace_common_return: > > ret x9 > > SYM_CODE_END(ftrace_common) > > > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > > -SYM_CODE_START(ftrace_graph_caller) > > - ldr x0, [sp, #S_PC] > > - sub x0, x0, #AARCH64_INSN_SIZE // ip (callsite's BL insn) > > - add x1, sp, #S_LR // parent_ip (callsite's LR) > > - ldr x2, [sp, #PT_REGS_SIZE] // parent fp (callsite's FP) > > - bl prepare_ftrace_return > > - b ftrace_common_return > > -SYM_CODE_END(ftrace_graph_caller) > > -#endif > > - > > #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > > > > /* > > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c > > index 4506c4a90ac1..35eb7c9b5e53 100644 > > --- a/arch/arm64/kernel/ftrace.c > > +++ b/arch/arm64/kernel/ftrace.c > > @@ -268,6 +268,22 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, > > } > > > > #ifdef CONFIG_DYNAMIC_FTRACE > > + > > +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS Is there a case were we have DYNAMIC_FTRACE but not DYNAMIC_FTRACE_WITH_REGS? > > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > > + struct ftrace_ops *op, struct ftrace_regs *fregs) > > +{ > > + /* > > + * Athough graph_ops doesn't have FTRACE_OPS_FL_SAVE_REGS set in flags, > > + * regs can't be NULL in DYNAMIC_FTRACE_WITH_REGS. By design, it should > > + * be fixed when DYNAMIC_FTRACE_WITH_ARGS is implemented. > > + */ > > + struct pt_regs *regs = arch_ftrace_get_regs(fregs); > > + unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); > > + > > + prepare_ftrace_return(ip, parent, frame_pointer(regs)); > > +} > > +#else You deleted ftrace_graph_caller above from entry-ftrace.S, if we can get here with some options, wouldn't that break the build? -- Steve > > /* > > * Turn on/off the call to ftrace_graph_caller() in ftrace_caller() > > * depending on @enable. > > @@ -297,5 +313,6 @@ int ftrace_disable_ftrace_graph_caller(void) > > { > > return ftrace_modify_graph_caller(false); > > } > > +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > > #endif /* CONFIG_DYNAMIC_FTRACE */ > > #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
On 2022/3/22 9:41 下午, Steven Rostedt wrote: > On Tue, 22 Mar 2022 20:48:00 +0800 > Chengming Zhou <zhouchengming@bytedance.com> wrote: > >> Hello, >> >> ping... have any comments? > > Hi Chengming, > > BTW, if you don't hear back for a week, it's OK to send a ping. You don't > need to wait a month. Usually, it's just that the maintainers have other > priorities and will try to look at it when they get a chance, but then > forget to do so :-/ Hi Steve, ok, I got it ;-) > > >> >> Thanks. >> >> On 2022/2/24 5:32 下午, Chengming Zhou wrote: >>> As we do in commit 0c0593b45c9b ("x86/ftrace: Make function graph >>> use ftrace directly"), we don't need special hook for graph tracer, >>> but instead we use graph_ops:func function to install return_hooker. >>> >>> Since commit 3b23e4991fb6 ("arm64: implement ftrace with regs") add >>> implementation for FTRACE_WITH_REGS on arm64, we can easily adopt >>> the same cleanup on arm64. And this cleanup only changes the >>> FTRACE_WITH_REGS implementation, so the mcount-based implementation >>> is unaffected. >>> >>> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> >>> --- >>> Changes in v3: >>> - Add comments in ftrace_graph_func() as suggested by Steve. >>> >>> Changes in v2: >>> - Remove FTRACE_WITH_REGS ftrace_graph_caller asm as suggested by Mark. >>> --- >>> arch/arm64/include/asm/ftrace.h | 7 +++++++ >>> arch/arm64/kernel/entry-ftrace.S | 17 ----------------- >>> arch/arm64/kernel/ftrace.c | 17 +++++++++++++++++ >>> 3 files changed, 24 insertions(+), 17 deletions(-) >>> >>> diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h >>> index 1494cfa8639b..dbc45a4157fa 100644 >>> --- a/arch/arm64/include/asm/ftrace.h >>> +++ b/arch/arm64/include/asm/ftrace.h >>> @@ -80,8 +80,15 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) >>> >>> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS >>> struct dyn_ftrace; >>> +struct ftrace_ops; >>> +struct ftrace_regs; >>> + >>> int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); >>> #define ftrace_init_nop ftrace_init_nop >>> + >>> +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, >>> + struct ftrace_ops *op, struct ftrace_regs *fregs); >>> +#define ftrace_graph_func ftrace_graph_func >>> #endif >>> >>> #define ftrace_return_address(n) return_address(n) >>> diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S >>> index e535480a4069..d42a205ef625 100644 >>> --- a/arch/arm64/kernel/entry-ftrace.S >>> +++ b/arch/arm64/kernel/entry-ftrace.S >>> @@ -97,12 +97,6 @@ SYM_CODE_START(ftrace_common) >>> SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) >>> bl ftrace_stub >>> >>> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER >>> -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller(); >>> - nop // If enabled, this will be replaced >>> - // "b ftrace_graph_caller" >>> -#endif >>> - >>> /* >>> * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved >>> * x19-x29 per the AAPCS, and we created frame records upon entry, so we need >>> @@ -127,17 +121,6 @@ ftrace_common_return: >>> ret x9 >>> SYM_CODE_END(ftrace_common) >>> >>> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER >>> -SYM_CODE_START(ftrace_graph_caller) >>> - ldr x0, [sp, #S_PC] >>> - sub x0, x0, #AARCH64_INSN_SIZE // ip (callsite's BL insn) >>> - add x1, sp, #S_LR // parent_ip (callsite's LR) >>> - ldr x2, [sp, #PT_REGS_SIZE] // parent fp (callsite's FP) >>> - bl prepare_ftrace_return >>> - b ftrace_common_return >>> -SYM_CODE_END(ftrace_graph_caller) >>> -#endif >>> - >>> #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ >>> >>> /* >>> diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c >>> index 4506c4a90ac1..35eb7c9b5e53 100644 >>> --- a/arch/arm64/kernel/ftrace.c >>> +++ b/arch/arm64/kernel/ftrace.c >>> @@ -268,6 +268,22 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, >>> } >>> >>> #ifdef CONFIG_DYNAMIC_FTRACE >>> + >>> +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > > Is there a case were we have DYNAMIC_FTRACE but not > DYNAMIC_FTRACE_WITH_REGS? Yes, when HAVE_DYNAMIC_FTRACE_WITH_REGS is not selected because of low gcc version. > >>> +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, >>> + struct ftrace_ops *op, struct ftrace_regs *fregs) >>> +{ >>> + /* >>> + * Athough graph_ops doesn't have FTRACE_OPS_FL_SAVE_REGS set in flags, >>> + * regs can't be NULL in DYNAMIC_FTRACE_WITH_REGS. By design, it should >>> + * be fixed when DYNAMIC_FTRACE_WITH_ARGS is implemented. >>> + */ >>> + struct pt_regs *regs = arch_ftrace_get_regs(fregs); >>> + unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); >>> + >>> + prepare_ftrace_return(ip, parent, frame_pointer(regs)); >>> +} >>> +#else > > You deleted ftrace_graph_caller above from entry-ftrace.S, if we can get > here with some options, wouldn't that break the build? The above ftrace_graph_caller deleted is only for CONFIG_DYNAMIC_FTRACE_WITH_REGS, and I tried using a low gcc version that doesn't select HAVE_DYNAMIC_FTRACE_WITH_REGS, it can build success. Thanks. > > -- Steve > > >>> /* >>> * Turn on/off the call to ftrace_graph_caller() in ftrace_caller() >>> * depending on @enable. >>> @@ -297,5 +313,6 @@ int ftrace_disable_ftrace_graph_caller(void) >>> { >>> return ftrace_modify_graph_caller(false); >>> } >>> +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ >>> #endif /* CONFIG_DYNAMIC_FTRACE */ >>> #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ >
On Tue, 22 Mar 2022 22:14:11 +0800 Chengming Zhou <zhouchengming@bytedance.com> wrote: > > You deleted ftrace_graph_caller above from entry-ftrace.S, if we can get > > here with some options, wouldn't that break the build? > > The above ftrace_graph_caller deleted is only for CONFIG_DYNAMIC_FTRACE_WITH_REGS, > and I tried using a low gcc version that doesn't select HAVE_DYNAMIC_FTRACE_WITH_REGS, > it can build success. OK, I didn't look too deep into this. I don't have an issue with this patch, but it needs to go through the arm64 tree. -- Steve
On 2022/3/22 22:49, Steven Rostedt wrote: > On Tue, 22 Mar 2022 22:14:11 +0800 > Chengming Zhou <zhouchengming@bytedance.com> wrote: > >>> You deleted ftrace_graph_caller above from entry-ftrace.S, if we can get >>> here with some options, wouldn't that break the build? >> >> The above ftrace_graph_caller deleted is only for CONFIG_DYNAMIC_FTRACE_WITH_REGS, >> and I tried using a low gcc version that doesn't select HAVE_DYNAMIC_FTRACE_WITH_REGS, >> it can build success. > > OK, I didn't look too deep into this. > > I don't have an issue with this patch, but it needs to go through the arm64 > tree. Hi Mark, would you mind picking this up for arm64 tree? Thanks. > > -- Steve
On Thu, Apr 07, 2022 at 10:26:53AM +0800, Chengming Zhou wrote: > On 2022/3/22 22:49, Steven Rostedt wrote: > > I don't have an issue with this patch, but it needs to go through the arm64 > > tree. > Hi Mark, would you mind picking this up for arm64 tree? [Different Mark here...] It's Catalin and Will who pick things up for the arm64 tree, AFAICT this was sent before -rc1 so you'll probably need to resend it to make sure it gets picked up.
On 2022/4/7 16:58, Mark Brown wrote: > On Thu, Apr 07, 2022 at 10:26:53AM +0800, Chengming Zhou wrote: >> On 2022/3/22 22:49, Steven Rostedt wrote: > >>> I don't have an issue with this patch, but it needs to go through the arm64 >>> tree. > >> Hi Mark, would you mind picking this up for arm64 tree? > > [Different Mark here...] > It's Catalin and Will who pick things up for the arm64 tree, AFAICT this > was sent before -rc1 so you'll probably need to resend it to make sure > it gets picked up. Ok, I will resend it. Thanks for reminding.
diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 1494cfa8639b..dbc45a4157fa 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -80,8 +80,15 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS struct dyn_ftrace; +struct ftrace_ops; +struct ftrace_regs; + int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #define ftrace_init_nop ftrace_init_nop + +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs); +#define ftrace_graph_func ftrace_graph_func #endif #define ftrace_return_address(n) return_address(n) diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S index e535480a4069..d42a205ef625 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -97,12 +97,6 @@ SYM_CODE_START(ftrace_common) SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) bl ftrace_stub -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller(); - nop // If enabled, this will be replaced - // "b ftrace_graph_caller" -#endif - /* * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved * x19-x29 per the AAPCS, and we created frame records upon entry, so we need @@ -127,17 +121,6 @@ ftrace_common_return: ret x9 SYM_CODE_END(ftrace_common) -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -SYM_CODE_START(ftrace_graph_caller) - ldr x0, [sp, #S_PC] - sub x0, x0, #AARCH64_INSN_SIZE // ip (callsite's BL insn) - add x1, sp, #S_LR // parent_ip (callsite's LR) - ldr x2, [sp, #PT_REGS_SIZE] // parent fp (callsite's FP) - bl prepare_ftrace_return - b ftrace_common_return -SYM_CODE_END(ftrace_graph_caller) -#endif - #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ /* diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 4506c4a90ac1..35eb7c9b5e53 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -268,6 +268,22 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, } #ifdef CONFIG_DYNAMIC_FTRACE + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) +{ + /* + * Athough graph_ops doesn't have FTRACE_OPS_FL_SAVE_REGS set in flags, + * regs can't be NULL in DYNAMIC_FTRACE_WITH_REGS. By design, it should + * be fixed when DYNAMIC_FTRACE_WITH_ARGS is implemented. + */ + struct pt_regs *regs = arch_ftrace_get_regs(fregs); + unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); + + prepare_ftrace_return(ip, parent, frame_pointer(regs)); +} +#else /* * Turn on/off the call to ftrace_graph_caller() in ftrace_caller() * depending on @enable. @@ -297,5 +313,6 @@ int ftrace_disable_ftrace_graph_caller(void) { return ftrace_modify_graph_caller(false); } +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ #endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
As we do in commit 0c0593b45c9b ("x86/ftrace: Make function graph use ftrace directly"), we don't need special hook for graph tracer, but instead we use graph_ops:func function to install return_hooker. Since commit 3b23e4991fb6 ("arm64: implement ftrace with regs") add implementation for FTRACE_WITH_REGS on arm64, we can easily adopt the same cleanup on arm64. And this cleanup only changes the FTRACE_WITH_REGS implementation, so the mcount-based implementation is unaffected. Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> --- Changes in v3: - Add comments in ftrace_graph_func() as suggested by Steve. Changes in v2: - Remove FTRACE_WITH_REGS ftrace_graph_caller asm as suggested by Mark. --- arch/arm64/include/asm/ftrace.h | 7 +++++++ arch/arm64/kernel/entry-ftrace.S | 17 ----------------- arch/arm64/kernel/ftrace.c | 17 +++++++++++++++++ 3 files changed, 24 insertions(+), 17 deletions(-)