Re: [RESEND PATCH net-next v3 4/5] ipv6: ioam: Support for IOAM injection with lwtunnels

On Wed, 26 May 2021 19:16:39 +0200 Justin Iurman wrote:

Add support for the IOAM inline insertion (only for the host-to-host use case)
which is per-route configured with lightweight tunnels. The target is iproute2
and the patch is ready. It will be posted as soon as this patchset is merged.
Here is an overview:

$ ip -6 ro ad fc00::1/128 encap ioam6 trace type 0x800000 ns 1 size 12 dev eth0

This example configures an IOAM Pre-allocated Trace option attached to the
fc00::1/128 prefix. The IOAM namespace (ns) is 1, the size of the pre-allocated
trace data block is 12 octets (size) and only the first IOAM data (bit 0:
hop_limit + node id) is included in the trace (type) represented as a bitfield.

The reason why the in-transit (IPv6-in-IPv6 encapsulation) use case is not
implemented is explained on the patchset cover.

Signed-off-by: Justin Iurman <redacted>

Please address the warnings from checkpatch --strict on this patches.

For all patches please make sure you don't use static inline in C
files, and let the compiler decide what to inline by itself.

+	if (trace->type.bit0) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit1) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit2) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit3) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit4) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit5) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit6) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit7) trace->nodelen += sizeof(__be32) / 4;
+	if (trace->type.bit8) trace->nodelen += sizeof(__be64) / 4;
+	if (trace->type.bit9) trace->nodelen += sizeof(__be64) / 4;
+	if (trace->type.bit10) trace->nodelen += sizeof(__be64) / 4;
+	if (trace->type.bit11) trace->nodelen += sizeof(__be32) / 4;

Seems simpler to do:

	nodelen += hweight16(field & MASK1) * (sizeof(__be32) / 4);
	nodelen += hweight16(field & MASK2) * (sizeof(__be64) / 4);