tile: remove dead is_dup_ack() function from tilepro net driver (48f2a4e1) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/net/ethernet/tile/tilepro.c

+0 −76

Original line number	Diff line number	Diff line
		@@ -89,9 +89,6 @@
		/* ISSUE: This has not been thoroughly tested (except at 1500). */
		#define TILE_NET_MTU 1500

		/* Define this to collapse "duplicate" acks. */
		/* #define IGNORE_DUP_ACKS */

		/* HACK: Define this to verify incoming packets. */
		/* #define TILE_NET_VERIFY_INGRESS */

		@@ -625,79 +622,6 @@ static void tile_net_handle_egress_timer(unsigned long arg)
		}


		#ifdef IGNORE_DUP_ACKS

		/*
		* Help detect "duplicate" ACKs. These are sequential packets (for a
		* given flow) which are exactly 66 bytes long, sharing everything but
		* ID=2@0x12, Hsum=2@0x18, Ack=4@0x2a, WinSize=2@0x30, Csum=2@0x32,
		* Tstamps=10@0x38. The ID's are +1, the Hsum's are -1, the Ack's are
		* +N, and the Tstamps are usually identical.
		*
		* NOTE: Apparently truly duplicate acks (with identical "ack" values),
		* should not be collapsed, as they are used for some kind of flow control.
		*/
		static bool is_dup_ack(char s1, char s2, unsigned int len)
		{
		int i;

		unsigned long long ignorable = 0;

		/* Identification. */
		ignorable \|= (1ULL << 0x12);
		ignorable \|= (1ULL << 0x13);

		/* Header checksum. */
		ignorable \|= (1ULL << 0x18);
		ignorable \|= (1ULL << 0x19);

		/* ACK. */
		ignorable \|= (1ULL << 0x2a);
		ignorable \|= (1ULL << 0x2b);
		ignorable \|= (1ULL << 0x2c);
		ignorable \|= (1ULL << 0x2d);

		/* WinSize. */
		ignorable \|= (1ULL << 0x30);
		ignorable \|= (1ULL << 0x31);

		/* Checksum. */
		ignorable \|= (1ULL << 0x32);
		ignorable \|= (1ULL << 0x33);

		for (i = 0; i < len; i++, ignorable >>= 1) {

		if ((ignorable & 1) \|\| (s1[i] == s2[i]))
		continue;

		#ifdef TILE_NET_DEBUG
		/* HACK: Mention non-timestamp diffs. */
		if (i < 0x38 && i != 0x2f &&
		net_ratelimit())
		pr_info("Diff at 0x%x\n", i);
		#endif

		return false;
		}

		#ifdef TILE_NET_NO_SUPPRESS_DUP_ACKS
		/* HACK: Do not suppress truly duplicate ACKs. */
		/* ISSUE: Is this actually necessary or helpful? */
		if (s1[0x2a] == s2[0x2a] &&
		s1[0x2b] == s2[0x2b] &&
		s1[0x2c] == s2[0x2c] &&
		s1[0x2d] == s2[0x2d]) {
		return false;
		}
		#endif

		return true;
		}

		#endif



		static void tile_net_discard_aux(struct tile_net_cpu *info, int index)
		{
		struct tile_netio_queue *queue = &info->queue;