From 136cd3450af8092f30d0e289806f08ac2aeee38f Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Thu, 3 Mar 2016 15:26:54 +1100 Subject: powerpc/module: Only try to generate the ftrace_caller() stub once Currently we generate the module stub for ftrace_caller() at the bottom of apply_relocate_add(). However apply_relocate_add() is potentially called more than once per module, which means we will try to generate the ftrace_caller() stub multiple times. Although the current code deals with that correctly, ie. it only generates a stub the first time, it would be clearer to only try to generate the stub once. Note also on first reading it may appear that we generate a different stub for each section that requires relocation, but that is not the case. The code in stub_for_addr() that searches for an existing stub uses sechdrs[me->arch.stubs_section], ie. the single stub section for this module. A cleaner approach is to only generate the ftrace_caller() stub once, from module_finalize(). Although the original code didn't check to see if the stub was actually generated correctly, it seems prudent to add a check, so do that. And an additional benefit is we can clean the ifdefs up a little. Finally we must propagate the const'ness of some of the pointers passed to module_finalize(), but that is also an improvement. Reviewed-by: Balbir Singh Reviewed-by: Torsten Duwe Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/module.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/powerpc/include/asm/module.h') diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h index dcfcad139bcc..74d25a749018 100644 --- a/arch/powerpc/include/asm/module.h +++ b/arch/powerpc/include/asm/module.h @@ -82,6 +82,15 @@ bool is_module_trampoline(u32 *insns); int module_trampoline_target(struct module *mod, u32 *trampoline, unsigned long *target); +#ifdef CONFIG_DYNAMIC_FTRACE +int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs); +#else +static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs) +{ + return 0; +} +#endif + struct exception_table_entry; void sort_ex_table(struct exception_table_entry *start, struct exception_table_entry *finish); -- cgit