[PATCH v1 10/22] powerpc/ftrace: Use CONFIG_FUNCTION_TRACER instead of CONFIG_DYNAMIC_FTRACE
Christophe Leroy
christophe.leroy at csgroup.eu
Fri May 6 21:41:02 AEST 2022
Le 18/04/2022 à 09:00, Naveen N. Rao a écrit :
> Christophe Leroy wrote:
>> Since commit 0c0c52306f47 ("powerpc: Only support DYNAMIC_FTRACE not
>> static"), CONFIG_DYNAMIC_FTRACE is always selected when
>> CONFIG_FUNCTION_TRACER is selected.
>>
>> To avoid confusion and have the reader wonder what's happen when
>> CONFIG_FUNCTION_TRACER is selected and CONFIG_DYNAMIC_FTRACE is not,
>> use CONFIG_FUNCTION_TRACER in ifdefs instead of CONFIG_DYNAMIC_FTRACE.
>>
>> As CONFIG_FUNCTION_GRAPH_TRACER depends on CONFIG_FUNCTION_TRACER,
>> ftrace.o doesn't need to appear for both symbols in Makefile.
>>
>> Then as ftrace.o is built only when CONFIG_FUNCTION_TRACER is selected
>
> and since it implies CONFIG_DYNAMIC_FTRACE, CONFIG_DYNAMIC_FTRACE is not
> needed in ftrace.c
Ok, added to the commit message
>
>> ifdef CONFIG_FUNCTION_TRACER is not needed in ftrace.c
>>
>> Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>
>> ---
>> arch/powerpc/include/asm/book3s/32/pgtable.h | 2 +-
>> arch/powerpc/include/asm/book3s/64/pgtable.h | 2 +-
>> arch/powerpc/include/asm/module.h | 4 ++--
>> arch/powerpc/include/asm/nohash/pgtable.h | 2 +-
>> arch/powerpc/kernel/module_32.c | 4 ++--
>> arch/powerpc/kernel/module_64.c | 6 +++---
>> arch/powerpc/kernel/trace/Makefile | 4 +---
>> arch/powerpc/kernel/trace/ftrace.c | 4 ----
>> 8 files changed, 11 insertions(+), 17 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h
>> b/arch/powerpc/include/asm/book3s/32/pgtable.h
>> index 772e00dc4ef1..992aed626eb4 100644
>> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
>> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
>> @@ -124,7 +124,7 @@ static inline bool pte_user(pte_t pte)
>> * on platforms where such control is possible.
>> */
>> #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) ||
>> defined(CONFIG_BDI_SWITCH) ||\
>> - defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE)
>> + defined(CONFIG_KPROBES) || defined(CONFIG_FUNCTION_TRACER)
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_X
>> #else
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX
>> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h
>> b/arch/powerpc/include/asm/book3s/64/pgtable.h
>> index 875730d5af40..cf01b609572f 100644
>> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
>> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
>> @@ -169,7 +169,7 @@
>> * on platforms where such control is possible.
>> */
>> #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) ||
>> defined(CONFIG_BDI_SWITCH) || \
>> - defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE)
>> + defined(CONFIG_KPROBES) || defined(CONFIG_FUNCTION_TRACER)
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_X
>> #else
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX
>> diff --git a/arch/powerpc/include/asm/module.h
>> b/arch/powerpc/include/asm/module.h
>> index 857d9ff24295..e6f5963fd96e 100644
>> --- a/arch/powerpc/include/asm/module.h
>> +++ b/arch/powerpc/include/asm/module.h
>> @@ -39,7 +39,7 @@ struct mod_arch_specific {
>> unsigned int init_plt_section;
>> #endif /* powerpc64 */
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> unsigned long tramp;
>> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
>> unsigned long tramp_regs;
>> @@ -68,7 +68,7 @@ struct mod_arch_specific {
>> # endif /* MODULE */
>> #endif
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> # ifdef MODULE
>> asm(".section .ftrace.tramp,\"ax\", at nobits; .align 3; .previous");
>> # endif /* MODULE */
>> diff --git a/arch/powerpc/include/asm/nohash/pgtable.h
>> b/arch/powerpc/include/asm/nohash/pgtable.h
>> index ac75f4ab0dba..2e8cf217a191 100644
>> --- a/arch/powerpc/include/asm/nohash/pgtable.h
>> +++ b/arch/powerpc/include/asm/nohash/pgtable.h
>> @@ -23,7 +23,7 @@
>> * on platforms where such control is possible.
>> */
>> #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) ||
>> defined(CONFIG_BDI_SWITCH) ||\
>> - defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE)
>> + defined(CONFIG_KPROBES) || defined(CONFIG_FUNCTION_TRACER)
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_X
>> #else
>> #define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX
>> diff --git a/arch/powerpc/kernel/module_32.c
>> b/arch/powerpc/kernel/module_32.c
>> index a0432ef46967..2aa368ce21c9 100644
>> --- a/arch/powerpc/kernel/module_32.c
>> +++ b/arch/powerpc/kernel/module_32.c
>> @@ -39,7 +39,7 @@ static unsigned int count_relocs(const Elf32_Rela
>> *rela, unsigned int num)
>> r_addend = rela[i].r_addend;
>> }
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> _count_relocs++; /* add one for ftrace_caller */
>> #endif
>> return _count_relocs;
>> @@ -288,7 +288,7 @@ int apply_relocate_add(Elf32_Shdr *sechdrs,
>> return 0;
>> }
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> int module_trampoline_target(struct module *mod, unsigned long addr,
>> unsigned long *target)
>> {
>> diff --git a/arch/powerpc/kernel/module_64.c
>> b/arch/powerpc/kernel/module_64.c
>> index 794720530442..b13a72665eee 100644
>> --- a/arch/powerpc/kernel/module_64.c
>> +++ b/arch/powerpc/kernel/module_64.c
>> @@ -207,7 +207,7 @@ static unsigned long get_stubs_size(const
>> Elf64_Ehdr *hdr,
>> }
>> }
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> /* make the trampoline to the ftrace_caller */
>> relocs++;
>> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
>> @@ -372,7 +372,7 @@ static bool is_mprofile_ftrace_call(const char *name)
>> {
>> if (!strcmp("_mcount", name))
>> return true;
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> if (!strcmp("ftrace_caller", name))
>> return true;
>> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
>> @@ -740,7 +740,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
>> return 0;
>> }
>>
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> +#ifdef CONFIG_FUNCTION_TRACER
>> int module_trampoline_target(struct module *mod, unsigned long addr,
>> unsigned long *target)
>> {
>
> The below two changes to trace/Makefile and trace/ftrace.c make sense,
> but I'm not sure the above changes are necessary.
>
> For generic code (outside arch/powerpc/kernel/trace), I think it is good
> to retain the actual dependency which is DYNAMIC_FTRACE. In my view,
> gating some of the above code on FUNCTION_TRACER is also confusing. The
> primary implication of always selecting DYNAMIC_FTRACE is within the
> powerpc trace code, and it is good to keep it that way.
Ok I keep only the changes to trace directory for now.
>
>> diff --git a/arch/powerpc/kernel/trace/Makefile
>> b/arch/powerpc/kernel/trace/Makefile
>> index fc32ec30b297..af8527538fe4 100644
>> --- a/arch/powerpc/kernel/trace/Makefile
>> +++ b/arch/powerpc/kernel/trace/Makefile
>> @@ -14,9 +14,7 @@ obj64-$(CONFIG_FUNCTION_TRACER) +=
>> ftrace_mprofile.o
>> else
>> obj64-$(CONFIG_FUNCTION_TRACER) += ftrace_64_pg.o
>> endif
>> -obj-$(CONFIG_FUNCTION_TRACER) += ftrace_low.o
>> -obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
>> -obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
>> +obj-$(CONFIG_FUNCTION_TRACER) += ftrace_low.o ftrace.o
>> obj-$(CONFIG_TRACING) += trace_clock.o
>>
>> obj-$(CONFIG_PPC64) += $(obj64-y)
>> diff --git a/arch/powerpc/kernel/trace/ftrace.c
>> b/arch/powerpc/kernel/trace/ftrace.c
>> index 2c7e42e439bb..188f59f4ee4a 100644
>> --- a/arch/powerpc/kernel/trace/ftrace.c
>> +++ b/arch/powerpc/kernel/trace/ftrace.c
>> @@ -28,9 +28,6 @@
>> #include <asm/syscall.h>
>> #include <asm/inst.h>
>>
>> -
>> -#ifdef CONFIG_DYNAMIC_FTRACE
>> -
>> /*
>> * We generally only have a single long_branch tramp and at most 2 or
>> 3 plt
>> * tramps generated. But, we don't use the plt tramps currently. We
>> also allot
>> @@ -783,7 +780,6 @@ int __init ftrace_dyn_arch_init(void)
>> return 0;
>> }
>> #endif
>> -#endif /* CONFIG_DYNAMIC_FTRACE */
>>
>> #ifdef CONFIG_FUNCTION_GRAPH_TRACER
>>
>> --
>> 2.35.1
>>
>
> - Naveen
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