| Message ID | 20220409153554.14470-1-zhouchengming@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4,1/2] ftrace: cleanup ftrace_graph_caller enable and disable | expand |
Hello, friendly ping :-) On 2022/4/9 23:35, Chengming Zhou wrote: > The ftrace_[enable,disable]_ftrace_graph_caller() are used to do > special hooks for graph tracer, which are not needed on some ARCHs > that use graph_ops:func function to install return_hooker. > > So introduce the weak version in ftrace core code to cleanup > in x86. > > Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> > --- > v4: > - put weak ftrace_enable,disable_ftrace_graph_caller() in > fgraph.c instead of ftrace.c as suggested by Steve. > > v3: > - consolidate two #if into a single #if, suggested by Steve. Thanks. > --- > arch/x86/kernel/ftrace.c | 17 ++--------------- > kernel/trace/fgraph.c | 18 ++++++++++++++++++ > 2 files changed, 20 insertions(+), 15 deletions(-) > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > index 1e31c7d21597..b09d73c2ba89 100644 > --- a/arch/x86/kernel/ftrace.c > +++ b/arch/x86/kernel/ftrace.c > @@ -579,9 +579,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops) > > #ifdef CONFIG_FUNCTION_GRAPH_TRACER > > -#ifdef CONFIG_DYNAMIC_FTRACE > - > -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS > +#if defined(CONFIG_DYNAMIC_FTRACE) && !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) > extern void ftrace_graph_call(void); > static const char *ftrace_jmp_replace(unsigned long ip, unsigned long addr) > { > @@ -610,18 +608,7 @@ int ftrace_disable_ftrace_graph_caller(void) > > return ftrace_mod_jmp(ip, &ftrace_stub); > } > -#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > -int ftrace_enable_ftrace_graph_caller(void) > -{ > - return 0; > -} > - > -int ftrace_disable_ftrace_graph_caller(void) > -{ > - return 0; > -} > -#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > -#endif /* !CONFIG_DYNAMIC_FTRACE */ > +#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > > /* > * Hook the return address and push it in the stack of return addrs > diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c > index 8f4fb328133a..289311680c29 100644 > --- a/kernel/trace/fgraph.c > +++ b/kernel/trace/fgraph.c > @@ -30,6 +30,24 @@ int ftrace_graph_active; > /* Both enabled by default (can be cleared by function_graph tracer flags */ > static bool fgraph_sleep_time = true; > > +/* > + * archs can override this function if they must do something > + * to enable hook for graph tracer. > + */ > +int __weak ftrace_enable_ftrace_graph_caller(void) > +{ > + return 0; > +} > + > +/* > + * archs can override this function if they must do something > + * to disable hook for graph tracer. > + */ > +int __weak ftrace_disable_ftrace_graph_caller(void) > +{ > + return 0; > +} > + > /** > * ftrace_graph_stop - set to permanently disable function graph tracing > *
On Sat, Apr 09, 2022 at 11:35:53PM +0800, Chengming Zhou wrote: > The ftrace_[enable,disable]_ftrace_graph_caller() are used to do > special hooks for graph tracer, which are not needed on some ARCHs > that use graph_ops:func function to install return_hooker. > > So introduce the weak version in ftrace core code to cleanup > in x86. > > Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> > --- > v4: > - put weak ftrace_enable,disable_ftrace_graph_caller() in > fgraph.c instead of ftrace.c as suggested by Steve. > > v3: > - consolidate two #if into a single #if, suggested by Steve. Thanks. > --- > arch/x86/kernel/ftrace.c | 17 ++--------------- > kernel/trace/fgraph.c | 18 ++++++++++++++++++ > 2 files changed, 20 insertions(+), 15 deletions(-) > > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > index 1e31c7d21597..b09d73c2ba89 100644 > --- a/arch/x86/kernel/ftrace.c > +++ b/arch/x86/kernel/ftrace.c > @@ -579,9 +579,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops) > > #ifdef CONFIG_FUNCTION_GRAPH_TRACER > > -#ifdef CONFIG_DYNAMIC_FTRACE > - > -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS > +#if defined(CONFIG_DYNAMIC_FTRACE) && !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) > extern void ftrace_graph_call(void); > static const char *ftrace_jmp_replace(unsigned long ip, unsigned long addr) > { > @@ -610,18 +608,7 @@ int ftrace_disable_ftrace_graph_caller(void) > > return ftrace_mod_jmp(ip, &ftrace_stub); > } > -#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > -int ftrace_enable_ftrace_graph_caller(void) > -{ > - return 0; > -} > - > -int ftrace_disable_ftrace_graph_caller(void) > -{ > - return 0; > -} > -#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > -#endif /* !CONFIG_DYNAMIC_FTRACE */ > +#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > > /* > * Hook the return address and push it in the stack of return addrs > diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c > index 8f4fb328133a..289311680c29 100644 > --- a/kernel/trace/fgraph.c > +++ b/kernel/trace/fgraph.c > @@ -30,6 +30,24 @@ int ftrace_graph_active; > /* Both enabled by default (can be cleared by function_graph tracer flags */ > static bool fgraph_sleep_time = true; > > +/* > + * archs can override this function if they must do something > + * to enable hook for graph tracer. > + */ > +int __weak ftrace_enable_ftrace_graph_caller(void) > +{ > + return 0; > +} > + > +/* > + * archs can override this function if they must do something > + * to disable hook for graph tracer. > + */ > +int __weak ftrace_disable_ftrace_graph_caller(void) > +{ > + return 0; > +} IIUC an arch should either: * Have ftrace_graph_call() * Have both ftrace_enable_ftrace_graph_caller() and ftrace_disable_ftrace_graph_caller() ... and I can't think of a reason an arch would need both ftrace_graph_call() *and* the enable/disable functions. Given that, could we drop the `__weak` and place these within ifdeffery, i.e. make the above: | #ifndef ftrace_graph_call | int ftrace_enable_ftrace_graph_caller(void) { return 0; } | int ftrace_disable_ftrace_graph_caller(void) { return 0; } | #endif /* ftrace_graph_call *. That way we'd catch cases when: * An architecture meant to provide one of these functions, but forgot (e.g. the name got typo'd) * An architecture provides an unnecessary implementation of either of these functions. Regardless, this looks ok to me. Steve, are you happy with this? I suspect we'd need to take this via the arm64 tree with the next patch, so we'd need your Ack. Thanks, Mark. > + > /** > * ftrace_graph_stop - set to permanently disable function graph tracing > * > -- > 2.35.1 >
Hi, On 2022/4/19 19:41, Mark Rutland wrote: > On Sat, Apr 09, 2022 at 11:35:53PM +0800, Chengming Zhou wrote: >> The ftrace_[enable,disable]_ftrace_graph_caller() are used to do >> special hooks for graph tracer, which are not needed on some ARCHs >> that use graph_ops:func function to install return_hooker. >> >> So introduce the weak version in ftrace core code to cleanup >> in x86. >> >> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> >> --- >> v4: >> - put weak ftrace_enable,disable_ftrace_graph_caller() in >> fgraph.c instead of ftrace.c as suggested by Steve. >> >> v3: >> - consolidate two #if into a single #if, suggested by Steve. Thanks. >> --- >> arch/x86/kernel/ftrace.c | 17 ++--------------- >> kernel/trace/fgraph.c | 18 ++++++++++++++++++ >> 2 files changed, 20 insertions(+), 15 deletions(-) >> >> diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c >> index 1e31c7d21597..b09d73c2ba89 100644 >> --- a/arch/x86/kernel/ftrace.c >> +++ b/arch/x86/kernel/ftrace.c >> @@ -579,9 +579,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops) >> >> #ifdef CONFIG_FUNCTION_GRAPH_TRACER >> >> -#ifdef CONFIG_DYNAMIC_FTRACE >> - >> -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS >> +#if defined(CONFIG_DYNAMIC_FTRACE) && !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) >> extern void ftrace_graph_call(void); >> static const char *ftrace_jmp_replace(unsigned long ip, unsigned long addr) >> { >> @@ -610,18 +608,7 @@ int ftrace_disable_ftrace_graph_caller(void) >> >> return ftrace_mod_jmp(ip, &ftrace_stub); >> } >> -#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ >> -int ftrace_enable_ftrace_graph_caller(void) >> -{ >> - return 0; >> -} >> - >> -int ftrace_disable_ftrace_graph_caller(void) >> -{ >> - return 0; >> -} >> -#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ >> -#endif /* !CONFIG_DYNAMIC_FTRACE */ >> +#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ >> >> /* >> * Hook the return address and push it in the stack of return addrs >> diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c >> index 8f4fb328133a..289311680c29 100644 >> --- a/kernel/trace/fgraph.c >> +++ b/kernel/trace/fgraph.c >> @@ -30,6 +30,24 @@ int ftrace_graph_active; >> /* Both enabled by default (can be cleared by function_graph tracer flags */ >> static bool fgraph_sleep_time = true; >> >> +/* >> + * archs can override this function if they must do something >> + * to enable hook for graph tracer. >> + */ >> +int __weak ftrace_enable_ftrace_graph_caller(void) >> +{ >> + return 0; >> +} >> + >> +/* >> + * archs can override this function if they must do something >> + * to disable hook for graph tracer. >> + */ >> +int __weak ftrace_disable_ftrace_graph_caller(void) >> +{ >> + return 0; >> +} > > IIUC an arch should either: > > * Have ftrace_graph_call() > > * Have both ftrace_enable_ftrace_graph_caller() and > ftrace_disable_ftrace_graph_caller() > > ... and I can't think of a reason an arch would need both ftrace_graph_call() > *and* the enable/disable functions. This way is more precise, but we have to add "#define ftrace_graph_call ftrace_graph_call" in all ARCH's asm/ftrace.h correctly. Previously we only need to define override ftrace_[enable,disable]_ftrace_graph_caller() in ARCH's ftrace.c, looks like a little more complexity? > > Given that, could we drop the `__weak` and place these within ifdeffery, i.e. > make the above: > > | #ifndef ftrace_graph_call > | int ftrace_enable_ftrace_graph_caller(void) { return 0; } > | int ftrace_disable_ftrace_graph_caller(void) { return 0; } > | #endif /* ftrace_graph_call *. > > That way we'd catch cases when: > > * An architecture meant to provide one of these functions, but forgot (e.g. the > name got typo'd) > > * An architecture provides an unnecessary implementation of either of these > functions. I tried this way today, and it works too. I'm ok with both way. Maybe I should send v5 with this patch unchanged first. Looking forward to Steve's opinion. Thanks. > > Regardless, this looks ok to me. Steve, are you happy with this? I suspect we'd > need to take this via the arm64 tree with the next patch, so we'd need your Ack. > > Thanks, > Mark. > >> + >> /** >> * ftrace_graph_stop - set to permanently disable function graph tracing >> * >> -- >> 2.35.1 >>
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 1e31c7d21597..b09d73c2ba89 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -579,9 +579,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops) #ifdef CONFIG_FUNCTION_GRAPH_TRACER -#ifdef CONFIG_DYNAMIC_FTRACE - -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS +#if defined(CONFIG_DYNAMIC_FTRACE) && !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) extern void ftrace_graph_call(void); static const char *ftrace_jmp_replace(unsigned long ip, unsigned long addr) { @@ -610,18 +608,7 @@ int ftrace_disable_ftrace_graph_caller(void) return ftrace_mod_jmp(ip, &ftrace_stub); } -#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ -int ftrace_enable_ftrace_graph_caller(void) -{ - return 0; -} - -int ftrace_disable_ftrace_graph_caller(void) -{ - return 0; -} -#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ -#endif /* !CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ /* * Hook the return address and push it in the stack of return addrs diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 8f4fb328133a..289311680c29 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -30,6 +30,24 @@ int ftrace_graph_active; /* Both enabled by default (can be cleared by function_graph tracer flags */ static bool fgraph_sleep_time = true; +/* + * archs can override this function if they must do something + * to enable hook for graph tracer. + */ +int __weak ftrace_enable_ftrace_graph_caller(void) +{ + return 0; +} + +/* + * archs can override this function if they must do something + * to disable hook for graph tracer. + */ +int __weak ftrace_disable_ftrace_graph_caller(void) +{ + return 0; +} + /** * ftrace_graph_stop - set to permanently disable function graph tracing *
The ftrace_[enable,disable]_ftrace_graph_caller() are used to do special hooks for graph tracer, which are not needed on some ARCHs that use graph_ops:func function to install return_hooker. So introduce the weak version in ftrace core code to cleanup in x86. Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> --- v4: - put weak ftrace_enable,disable_ftrace_graph_caller() in fgraph.c instead of ftrace.c as suggested by Steve. v3: - consolidate two #if into a single #if, suggested by Steve. Thanks. --- arch/x86/kernel/ftrace.c | 17 ++--------------- kernel/trace/fgraph.c | 18 ++++++++++++++++++ 2 files changed, 20 insertions(+), 15 deletions(-)