[igt-dev] [PATCH 1/4] lib/igt_kmod: simplify check for loaded module

[Chris Wilson]

Quoting Lucas De Marchi (2019-04-04 23:39:22)
> No need to go through the list of loaded modules and check one by one.
> We can just check if it's in "live" state or if it's builtin.
> 
> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
> ---
>  lib/igt_kmod.c | 19 ++++++-------------
>  1 file changed, 6 insertions(+), 13 deletions(-)
> 
> diff --git a/lib/igt_kmod.c b/lib/igt_kmod.c
> index 91662eb3..8d5ac788 100644
> --- a/lib/igt_kmod.c
> +++ b/lib/igt_kmod.c
> @@ -119,25 +119,18 @@ bool
>  igt_kmod_is_loaded(const char *mod_name)
>  {
>         struct kmod_ctx *ctx = kmod_ctx();
> -       struct kmod_list *mod, *list;
> +       enum kmod_module_initstate state;
> +       struct kmod_module *kmod;
>         bool ret = false;
>  
> -       if (kmod_module_new_from_loaded(ctx, &list) < 0)
> +       if (kmod_module_new_from_name(ctx, mod_name, &kmod) < 0)
>                 goto out;
>  
> -       kmod_list_foreach(mod, list) {
> -               struct kmod_module *kmod = kmod_module_get_module(mod);
> -               const char *kmod_name = kmod_module_get_name(kmod);
> +       state = kmod_module_get_initstate(kmod);
> +       ret = state == KMOD_MODULE_LIVE || state == KMOD_MODULE_BUILTIN;

So if the module is being loaded, it is also present. If the module is
being unloaded it is currently present and we need to wait.

Looks like this should be ret = state >= 0 ? If the module is any of
LIVE/BUILTIN/COMING/GOING it is presently loaded.
-Chris