Le 18/05/2022 à 11:45, Naveen N. Rao a écrit : > Christophe Leroy wrote: >> A lot of #ifdefs can be replaced by IS_ENABLED() >> >> Do so. >> >> This requires to have kernel_toc_addr() defined at all time >> as well as PPC_INST_LD_TOC and PPC_INST_STD_LR. >> >> Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu> >> --- >> v2: Moved the setup of pop outside of the big if()/else() in >> __ftrace_make_nop() >> --- >> arch/powerpc/include/asm/code-patching.h | 2 - >> arch/powerpc/include/asm/module.h | 2 - >> arch/powerpc/include/asm/sections.h | 24 +-- >> arch/powerpc/kernel/trace/ftrace.c | 182 +++++++++++------------ >> 4 files changed, 103 insertions(+), 107 deletions(-) >> > > <snip> > >> @@ -710,6 +707,9 @@ void arch_ftrace_update_code(int command) >> >> #ifdef CONFIG_PPC64 >> #define PACATOC offsetof(struct paca_struct, kernel_toc) >> +#else >> +#define PACATOC 0 >> +#endif > > This conflicts with my fix for the ftrace init tramp: > https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220516071422.463738-1-naveen.n....@linux.vnet.ibm.com/ > > > > It probably makes sense to retain #ifdef CONFIG_PPC64, so that we can > get rid of the PACATOC. Here is an incremental diff:
Ah yes, it makes sense. Initial purpose was to de-duplicate ftrace_dyn_arch_init(), but as ftrace_dyn_arch_init() is defined as a weak nop function in kernel/trace/ftrace.c we don't need it for PPC32 at all. And then kernel_toc_addr() could remain inside #ifdef CONFIG_PPC64 in asm/section.h > > diff --git a/arch/powerpc/kernel/trace/ftrace.c > b/arch/powerpc/kernel/trace/ftrace.c > index da1a2f8ebb72f3..28169a1ccc7377 100644 > --- a/arch/powerpc/kernel/trace/ftrace.c > +++ b/arch/powerpc/kernel/trace/ftrace.c > @@ -701,11 +701,6 @@ void arch_ftrace_update_code(int command) > } > > #ifdef CONFIG_PPC64 > -#define PACATOC offsetof(struct paca_struct, kernel_toc) > -#else > -#define PACATOC 0 > -#endif > - > extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[]; > > void ftrace_free_init_tramp(void) > @@ -724,7 +719,7 @@ int __init ftrace_dyn_arch_init(void) > int i; > unsigned int *tramp[] = { ftrace_tramp_text, ftrace_tramp_init }; > u32 stub_insns[] = { > - PPC_RAW_LD(_R12, _R13, PACATOC), > + PPC_RAW_LD(_R12, _R13, offsetof(struct paca_struct, kernel_toc)), > PPC_RAW_ADDIS(_R12, _R12, 0), > PPC_RAW_ADDI(_R12, _R12, 0), > PPC_RAW_MTCTR(_R12), > @@ -733,9 +728,6 @@ int __init ftrace_dyn_arch_init(void) > unsigned long addr; > long reladdr; > > - if (IS_ENABLED(CONFIG_PPC32)) > - return 0; > - > addr = ppc_global_function_entry((void *)FTRACE_REGS_ADDR); > reladdr = addr - kernel_toc_addr(); > > @@ -754,6 +746,7 @@ int __init ftrace_dyn_arch_init(void) > > return 0; > } > +#endif > > #ifdef CONFIG_FUNCTION_GRAPH_TRACER > > > - Naveen