Re: [Intel-gfx] [PATCH v5 1/2] module: update dependencies at try_module_get()

From: Andi Shyti
Date: Thu May 05 2022 - 17:36:17 EST


Hi Mauro,

[...]

> +static int ref_module_dependency(struct module *mod, struct module *this)
> +{
> + int ret;
> +
> + if (!this || !this->name)
> + return -EINVAL;
> +
> + if (mod == this)
> + return 0;
> +
> + mutex_lock(&module_mutex);
> +
> + ret = ref_module(this, mod);
> +
> +#ifdef CONFIG_MODULE_UNLOAD
> + if (ret)
> + goto ret;
> +
> + ret = sysfs_create_link(mod->holders_dir,
> + &this->mkobj.kobj, this->name);
> +#endif
> +
> +ret:
> + mutex_unlock(&module_mutex);
> + return ret;
> +}
> +
> /* Clear the unload stuff of the module. */
> static void module_unload_free(struct module *mod)
> {
> @@ -841,24 +886,16 @@ void __module_get(struct module *module)
> }
> EXPORT_SYMBOL(__module_get);
>
> -bool try_module_get(struct module *module)
> +bool try_module_get_owner(struct module *module, struct module *this)
> {
> - bool ret = true;
> + int ret = __try_module_get(module);
>
> - if (module) {
> - preempt_disable();
> - /* Note: here, we can fail to get a reference */
> - if (likely(module_is_live(module) &&
> - atomic_inc_not_zero(&module->refcnt) != 0))
> - trace_module_get(module, _RET_IP_);
> - else
> - ret = false;
> + if (ret)
> + ref_module_dependency(module, this);

do we care about the return value here?

Andi

>
> - preempt_enable();
> - }
> return ret;
> }
> -EXPORT_SYMBOL(try_module_get);
> +EXPORT_SYMBOL(try_module_get_owner);
>
> void module_put(struct module *module)
> {
> --
> 2.35.1