Hi!
Le mercredi 1 novembre 2023, 01:15:09 EET Masami Hiramatsu a écrit :
> Hi,
>
> On Tue, 31 Oct 2023 23:24:43 +0200
>
> Francis Laniel <flan...@linux.microsoft.com> wrote:
> > > @@ -729,17 +744,55 @@ static int count_mod_symbols(void *data, const
> > > char
> > > *name, unsigned long unused) return 0;
> > >
> > > }
> > >
> > > -static unsigned int number_of_same_symbols(char *func_name)
> > > +static unsigned int number_of_same_symbols(const char *mod, const char
> > > *func_name) {
> > >
> > > struct sym_count_ctx ctx = { .count = 0, .name = func_name };
> > >
> > > - kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
> > > + if (!mod)
> > > + kallsyms_on_each_match_symbol(count_symbols, func_name,
> >
> > &ctx.count);
> >
> > > - module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
> > > + module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx);
> >
> > I may be missing something here or reviewing too quickly.
> > Wouldn't this function return count to be 0 if func_name is only part of
> > the module named mod?
>
> No, please read below.
>
> > Indeed, if the function is not in kernel symbol,
> > kallsyms_on_each_match_symbol() will not loop.
> > And, by giving mod to module_kallsyms_on_each_symbol(), the corresponding
> > module will be skipped, so count_mob_symbols() would not be called.
> > Hence, we would have 0 as count, which would lead to ENOENT later.
>
> Would you mean the case func_name is on the specific module?
> If 'mod' is specified, module_kallsyms_on_each_symbol() only loops on
> symbols in the module names 'mod'.
>
> int module_kallsyms_on_each_symbol(const char *modname,
> int (*fn)(void *, const char *, unsigned
> long), void *data)
> {
> struct module *mod;
> unsigned int i;
> int ret = 0;
>
> mutex_lock(&module_mutex);
> list_for_each_entry(mod, &modules, list) {
> struct mod_kallsyms *kallsyms;
>
> if (mod->state == MODULE_STATE_UNFORMED)
> continue;
>
> if (modname && strcmp(modname, mod->name))
> continue;
> ...
>
> So with above change, 'if mod is not specified, search the symbols in kernel
> and all modules. If mod is sepecified, search the symbol on the specific
> module'.
>
> Thus, "if func_name is only part of the module named mod", the
> module_kallsyms_on_each_symbol() will count the 'func_name' in 'mod' module
> correctly.
Sorry, I looked to quickly and forgot about the return value of strcmp()...
From the code, everything seems OK!
If I have some time, I will test it and potentially come back with a "Tested-
by" tag but without any warranty.
> Thank you,
>
>
> Thank you,
Best regards.
