Re: [PATCH dwarves 1/1] dwarf_loader: Support for btf:type_tag

[Eduard Zingerman <eddyz87@gmail.com>]

On Tue, 2023-03-14 at 10:30 +0000, Alan Maguire wrote:
[...]
> > See also:
> > [1] Mailing list discussion regarding `btf:type_tag`
> >     https://lore.kernel.org/bpf/87r0w9jjoq.fsf@oracle.com/
> > 
> 
> I know there's a v2 coming but one suggestion and one other issue below..
> 
> this is a great explanation, thanks for the details! one other thing that might help
> here is specifying that the solution adopted is option 2 described in that discussion
> (at least I think it is?).

Hi Alan,

Yes, it's option #2, sorry should have noted it in the original message.

[...]

> > -static void ftype__recode_dwarf_types(struct tag *tag, struct cu *cu);
> > +/** Add @tuple to @ctx->mappings array, extend it if necessary. */
> > +static int push_btf_type_tag_mapping(struct btf_type_tag_mapping *tuple,
> > +				     struct recode_context *ctx)
> > +{
> > +	if (ctx->nr_allocated == ctx->nr_entries) {
> > +		uint32_t new_nr = ctx->nr_allocated * 2;
> > +		void *new_array = reallocarray(ctx->mappings, new_nr,
> > +					       sizeof(ctx->mappings[0]));
> 
> older libcs won't have reallocarray; might be good to either replace with realloc
> or define our own variant in dutil.h like was done with libbpf_reallocarray()?

Will use `realloc()`, thank you for the heads-up.

Thanks,
Eduard