> From: Stephen Hemminger [mailto:[email protected]]
> Sent: Monday, 31 August 2026 18.06
> 
> On Thu, 27 Aug 2026 13:55:55 +0000
> Morten Brørup <[email protected]> wrote:
> 
> > +__rte_stack_pile_pop(struct rte_stack *s,
> > +           void **obj_table,
> 
> NAK to using always_inline on a function this big
> It generates worse code in a lot of cases because of register spill.

OK, I will change it to "inline", and let the compiler decide.
Then we don't have to discuss which is better. :-)

I'll change the pull function too.

BTW, it's not quite as big as it looks.
Here's the function without comments, assertions and empty lines:

static __rte_always_inline unsigned int
__rte_stack_pile_pop(struct rte_stack *s,
                void **obj_table,
                unsigned int n)
{
        struct rte_stack_pile *pile = &s->stack_pile;
        struct rte_stack_pile_bulk_elem *bulk_first = NULL, *bulk_last = NULL;
        struct rte_stack_lf_elem *solo_first = NULL, *solo_last = NULL;
        unsigned int n_bulk = n / RTE_STACK_PILE_BULK_SIZE;
        unsigned int n_solo = n & (RTE_STACK_PILE_BULK_SIZE - 1);
        if (unlikely(n_bulk == 0)) {
                if (unlikely(n_solo == 0))
                        return 0;
                goto solo;
        }
bulk:
        bulk_first = __rte_stack_pile_bulk_pop_elems(&pile->bulk, n_bulk, 
obj_table, &bulk_last);
        if (unlikely(bulk_first == NULL)) {
                unsigned int delta_bulk = n_bulk - 
__rte_stack_lf_elems_count(&pile->bulk);
                if (unlikely((int)delta_bulk <= 0))
                        delta_bulk = 1;
                n_bulk -= delta_bulk;
                n_solo += RTE_STACK_PILE_BULK_SIZE * delta_bulk;
                if (n_bulk == 0)
                        goto solo;
                goto bulk;
        }
        obj_table += n_bulk * RTE_STACK_PILE_BULK_SIZE;
        if (likely(n_solo == 0))
                goto done;
solo:
        solo_first = __rte_stack_lf_pop_elems(&pile->solo, n_solo,
                        obj_table, &solo_last);
        if (solo_first != NULL)
                goto done;
        if (unlikely(n_solo >= RTE_STACK_PILE_BULK_SIZE))
                goto fail;
        if (unlikely(__rte_stack_pile_pop_frag(pile, obj_table, n_solo) == 0))
                goto fail;
done:
        if (bulk_first != NULL)
                __rte_stack_pile_bulk_push_elems(&pile->free_bulk, bulk_first, 
bulk_last, n_bulk);
        if (solo_first != NULL)
                __rte_stack_lf_push_elems(&pile->free_solo, solo_first, 
solo_last, n_solo);
        return n;
fail:
        if (bulk_first != NULL)
                __rte_stack_pile_bulk_push_elems(&pile->bulk, bulk_first, 
bulk_last, n_bulk);
        return 0;
}

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