On 12/18/25 8:34 AM, Dave Hansen wrote:
On 12/15/25 15:33, Ross Philipson wrote:
+static inline void *txt_sinit_mle_data_start(void *heap)
+{
+       return heap + txt_bios_data_size(heap) +
+               txt_os_mle_data_size(heap) +
+               txt_os_sinit_data_size(heap) + sizeof(u64);
+}

So each one of these walks through the entire table?

Maybe I'm naive, but wouldn't this all be a lot more sane if it was just
parsed *once* into a table of pointers?

enum {
        FIELD1,
        FIELD2,
        FIELD3,
        MAX_NR
};

void *parseit(u8 *heap)
{
        void *ptr_array[MAX_NR] = {};
        void *place = heap;

        for (int i = 0; i < MAX_NR; i++) {
                // The buffer starts with the length:
                u32 *size_ptr = place;

                // Consume the length:
                place += sizeof(*size_ptr);

                // Point at the data:
                ptr_array[i] = place;
                // Consume the data:
                place += *size_ptr;
        }
        // along with some sanity checks
}

Then, to access FIELDs you do:

        struct field1_struct *f1s = ptr_array[FIELD1];
        struct field2_struct *f1s = ptr_array[FIELD2];

Yeah, it means keeping that pointer array around. But <shrug>. It's also
not about performance. That ^ is a billion times easier to understand
because it lays out the "heap" logic in one place. You don't have to
recurse through half a dozen helpers to figure things out.

That is an excellent idea, we will do that. I may be able to use the same the index scheme when I do the early remap operations too. That walks the heap each time but does not have to. It just wants a pointer to what to map.

Thank you,
Ross



Reply via email to