From bed0d9a50dacee6fcf785c555cfb0d2573355afc Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 10 May 2022 14:26:13 +0200 Subject: ftrace: Add ftrace_lookup_symbols function Adding ftrace_lookup_symbols function that resolves array of symbols with single pass over kallsyms. The user provides array of string pointers with count and pointer to allocated array for resolved values. int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs) It iterates all kallsyms symbols and tries to loop up each in provided symbols array with bsearch. The symbols array needs to be sorted by name for this reason. We also check each symbol to pass ftrace_location, because this API will be used for fprobe symbols resolving. Suggested-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Reviewed-by: Masami Hiramatsu Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20220510122616.2652285-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/ftrace.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 4816b7e11047..820500430eae 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -303,6 +303,8 @@ int unregister_ftrace_function(struct ftrace_ops *ops); extern void ftrace_stub(unsigned long a0, unsigned long a1, struct ftrace_ops *op, struct ftrace_regs *fregs); + +int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs); #else /* !CONFIG_FUNCTION_TRACER */ /* * (un)register_ftrace_function must be a macro since the ops parameter @@ -313,6 +315,10 @@ extern void ftrace_stub(unsigned long a0, unsigned long a1, static inline void ftrace_kill(void) { } static inline void ftrace_free_init_mem(void) { } static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { } +static inline int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs) +{ + return -EOPNOTSUPP; +} #endif /* CONFIG_FUNCTION_TRACER */ struct ftrace_func_entry { -- cgit v1.2.3-71-gd317