Re: [PATCH v5 1/2] alloc_tag: move release_module_tags() above reserve_module_tags()

[Suren Baghdasaryan]

On Tue, Aug 11, 2026 at 10:41 PM Hao Ge <hao.ge@xxxxxxxxx> wrote:
>
> release_module_tags() is a cleanup helper. reserve_module_tags() can
> also fail after storing the reservation in the maple tree, in which
> case it should call release_module_tags() to undo it. Move the helper
> above reserve_module_tags() so no forward declaration is needed.
>
> No functional change.
>
> Fixes: 4835f747d3ed ("alloc_tag: support for page allocation tag compression")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Hao Ge <hao.ge@xxxxxxxxx>

Acked-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>

> ---
>  mm/alloc_tag.c | 92 +++++++++++++++++++++++++-------------------------
>  1 file changed, 46 insertions(+), 46 deletions(-)
>
> diff --git a/mm/alloc_tag.c b/mm/alloc_tag.c
> index 52aece27b00e..af44f90379f2 100644
> --- a/mm/alloc_tag.c
> +++ b/mm/alloc_tag.c
> @@ -835,6 +835,52 @@ static int vm_module_tags_populate(void)
>         return 0;
>  }
>
> +static void release_module_tags(struct module *mod, bool used)
> +{
> +       MA_STATE(mas, &mod_area_mt, module_tags.size, module_tags.size);
> +       struct alloc_tag *start_tag;
> +       struct alloc_tag *end_tag;
> +       struct module *val;
> +
> +       mas_lock(&mas);
> +       mas_for_each_rev(&mas, val, 0)
> +               if (val == mod)
> +                       break;
> +
> +       if (!val) /* module not found */
> +               goto out;
> +
> +       if (!used)
> +               goto release_area;
> +
> +       start_tag = (struct alloc_tag *)(module_tags.start_addr + mas.index);
> +       end_tag = (struct alloc_tag *)(module_tags.start_addr + mas.last);
> +       if (!clean_unused_counters(start_tag, end_tag)) {
> +               struct alloc_tag *tag;
> +
> +               for (tag = start_tag; tag <= end_tag; tag++) {
> +                       struct alloc_tag_counters counter;
> +
> +                       if (!tag->counters)
> +                               continue;
> +
> +                       counter = alloc_tag_read(tag);
> +                       pr_info("%s:%u module %s func:%s has %llu allocated at module unload\n",
> +                               tag->ct.filename, tag->ct.lineno, tag->ct.modname,
> +                               tag->ct.function, counter.bytes);
> +               }
> +       } else {
> +               used = false;
> +       }
> +release_area:
> +       mas_store(&mas, used ? &unloaded_mod : NULL);
> +       val = mas_prev_range(&mas, 0);
> +       if (val == &prepend_mod)
> +               mas_store(&mas, NULL);
> +out:
> +       mas_unlock(&mas);
> +}
> +
>  static void *reserve_module_tags(struct module *mod, unsigned long size,
>                                  unsigned int prepend, unsigned long align)
>  {
> @@ -922,52 +968,6 @@ static void *reserve_module_tags(struct module *mod, unsigned long size,
>         return (struct alloc_tag *)(module_tags.start_addr + offset);
>  }
>
> -static void release_module_tags(struct module *mod, bool used)
> -{
> -       MA_STATE(mas, &mod_area_mt, module_tags.size, module_tags.size);
> -       struct alloc_tag *start_tag;
> -       struct alloc_tag *end_tag;
> -       struct module *val;
> -
> -       mas_lock(&mas);
> -       mas_for_each_rev(&mas, val, 0)
> -               if (val == mod)
> -                       break;
> -
> -       if (!val) /* module not found */
> -               goto out;
> -
> -       if (!used)
> -               goto release_area;
> -
> -       start_tag = (struct alloc_tag *)(module_tags.start_addr + mas.index);
> -       end_tag = (struct alloc_tag *)(module_tags.start_addr + mas.last);
> -       if (!clean_unused_counters(start_tag, end_tag)) {
> -               struct alloc_tag *tag;
> -
> -               for (tag = start_tag; tag <= end_tag; tag++) {
> -                       struct alloc_tag_counters counter;
> -
> -                       if (!tag->counters)
> -                               continue;
> -
> -                       counter = alloc_tag_read(tag);
> -                       pr_info("%s:%u module %s func:%s has %llu allocated at module unload\n",
> -                               tag->ct.filename, tag->ct.lineno, tag->ct.modname,
> -                               tag->ct.function, counter.bytes);
> -               }
> -       } else {
> -               used = false;
> -       }
> -release_area:
> -       mas_store(&mas, used ? &unloaded_mod : NULL);
> -       val = mas_prev_range(&mas, 0);
> -       if (val == &prepend_mod)
> -               mas_store(&mas, NULL);
> -out:
> -       mas_unlock(&mas);
> -}
> -
>  static int load_module(struct module *mod, struct codetag *start, struct codetag *stop)
>  {
>         /* Allocate module alloc_tag percpu counters */
> --
> 2.25.1
>