Inconsistency in maximum rank

[wesbland]

It looks to me as if there is an inconsistency in how UCC determines the maximum rank within a team. On the one hand, there's this code in src/utils/ucc_datastruct.h that says the maximum rank is UINT32_MAX - 1 (4,294,967,295):

ucc/src/utils/ucc_datastruct.h

Lines 14 to 15 in 56df2df

	#define UCC_RANK_INVALID UINT32_MAX
	#define UCC_RANK_MAX UCC_RANK_INVALID - 1

On the other hand, within the UCP TL, this code seems to only handle a maximum of 24 bits (16,777,216):

ucc/src/components/tl/ucp/tl_ucp_tag.h

Lines 9 to 22 in 56df2df

	/*
	* UCP tag structure:
	*
	* 01 | 01234567 01234567 | 234 | 567 | 01234567 01234567 01234567 | 01234567 01234567
	* | | | | |
	* RESERV(2) | message tag (16) | SCOPE(3) | SCOPE_ID(3) | source rank (24) | team id (16)
	*/
	#define UCC_TL_UCP_RESERVED_BITS 2
	#define UCC_TL_UCP_SCOPE_BITS 3
	#define UCC_TL_UCP_SCOPE_ID_BITS 3
	#define UCC_TL_UCP_TAG_BITS 16
	#define UCC_TL_UCP_SENDER_BITS 24
	#define UCC_TL_UCP_ID_BITS 16

I don't think it's likely that either maximum is being hit right now, but it would probably be good to be consistent. Particularly as different TLs could potentially support different maximum sizes.

[vspetrov]

you are right. probably need to add a TL iface to query max size and in runtime disqualify TLs if user team size exceeds max supported. While UCC_RANK_MAX is internal max for any TL.