Re: [PATCH v5 4/6] alloc_tag: add accuracy based filtering to ioctl

[Suren Baghdasaryan]

On Mon, Jun 15, 2026 at 4:04 PM Abhishek Bapat <abhishekbapat@xxxxxxxxxx> wrote:
>
> Extend the allocinfo filtering mechanism to allow users to filter tags
> based on their accuracy.
>
> Signed-off-by: Abhishek Bapat <abhishekbapat@xxxxxxxxxx>
> Acked-by: Hao Ge <hao.ge@xxxxxxxxx>

Acked-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>

> ---
>  include/uapi/linux/alloc_tag.h | 4 ++++
>  lib/alloc_tag.c                | 8 ++++++++
>  2 files changed, 12 insertions(+)
>
> diff --git a/include/uapi/linux/alloc_tag.h b/include/uapi/linux/alloc_tag.h
> index 7f5acbb44c14..6ea39c4869fe 100644
> --- a/include/uapi/linux/alloc_tag.h
> +++ b/include/uapi/linux/alloc_tag.h
> @@ -26,6 +26,8 @@ struct allocinfo_tag {
>         char function[ALLOCINFO_STR_SIZE];
>         char filename[ALLOCINFO_STR_SIZE];
>         __u64 lineno;
> +       /* filter criteria only; see allocinfo_counter.accurate for actual accuracy */
> +       __u64 inaccurate;
>  };
>
>  /* The alignment ensures 32-bit compatible interfaces are not broken */
> @@ -45,6 +47,7 @@ enum {
>         ALLOCINFO_FILTER_FUNCTION,
>         ALLOCINFO_FILTER_FILENAME,
>         ALLOCINFO_FILTER_LINENO,
> +       ALLOCINFO_FILTER_INACCURATE,
>         ALLOCINFO_FILTER_MIN_SIZE,
>         ALLOCINFO_FILTER_MAX_SIZE,
>         __ALLOCINFO_FILTER_LAST = ALLOCINFO_FILTER_MAX_SIZE
> @@ -54,6 +57,7 @@ enum {
>  #define ALLOCINFO_FILTER_MASK_FUNCTION         (1 << ALLOCINFO_FILTER_FUNCTION)
>  #define ALLOCINFO_FILTER_MASK_FILENAME         (1 << ALLOCINFO_FILTER_FILENAME)
>  #define ALLOCINFO_FILTER_MASK_LINENO           (1 << ALLOCINFO_FILTER_LINENO)
> +#define ALLOCINFO_FILTER_MASK_INACCURATE       (1 << ALLOCINFO_FILTER_INACCURATE)
>  #define ALLOCINFO_FILTER_MASK_MIN_SIZE         (1 << ALLOCINFO_FILTER_MIN_SIZE)
>  #define ALLOCINFO_FILTER_MASK_MAX_SIZE         (1 << ALLOCINFO_FILTER_MAX_SIZE)
>
> diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
> index b3d21834b61e..4fb3653cb876 100644
> --- a/lib/alloc_tag.c
> +++ b/lib/alloc_tag.c
> @@ -253,6 +253,8 @@ static bool matches_filter(struct codetag *ct, struct allocinfo_filter *filter,
>                            struct alloc_tag_counters *counters,
>                            bool *fetched_counters)
>  {
> +       bool inaccurate;
> +
>         if (!filter || !filter->mask)
>                 return true;
>
> @@ -278,6 +280,12 @@ static bool matches_filter(struct codetag *ct, struct allocinfo_filter *filter,
>             ct->lineno != filter->fields.lineno)
>                 return false;
>
> +       if (filter->mask & ALLOCINFO_FILTER_MASK_INACCURATE) {
> +               inaccurate = !!(ct->flags & CODETAG_FLAG_INACCURATE);
> +               if (inaccurate != !!(filter->fields.inaccurate))
> +                       return false;
> +       }
> +
>         if (filter->mask & (ALLOCINFO_FILTER_MASK_MIN_SIZE | ALLOCINFO_FILTER_MASK_MAX_SIZE)) {
>                 if (!*fetched_counters) {
>                         *counters = allocinfo_prefetch_counters(ct);
> --
> 2.54.0.1136.gdb2ca164c4-goog
>