Merge branch 'net-timestamp-introduce-a-flag-to-filter-out-rx-software-and-hardware-report'

Jason Xing says:

====================
net-timestamp: introduce a flag to filter out rx software and hardware report

When one socket is set SOF_TIMESTAMPING_RX_SOFTWARE which means the
whole system turns on the netstamp_needed_key button, other sockets
that only have SOF_TIMESTAMPING_SOFTWARE will be affected and then
print the rx timestamp information even without setting
SOF_TIMESTAMPING_RX_SOFTWARE generation flag.

How to solve it without breaking users?
We introduce a new flag named SOF_TIMESTAMPING_OPT_RX_FILTER. Using
it together with SOF_TIMESTAMPING_SOFTWARE can stop reporting the
rx software timestamp.

Similarly, we also filter out the hardware case where one process
enables the rx hardware generation flag, then another process only
passing SOF_TIMESTAMPING_RAW_HARDWARE gets the timestamp. So we can set
both SOF_TIMESTAMPING_RAW_HARDWARE and SOF_TIMESTAMPING_OPT_RX_FILTER
to stop reporting rx hardware timestamp after this patch applied.

v6: https://lore.kernel.org/20240906095640.77533-1-kerneljasonxing@gmail.com
v5: https://lore.kernel.org/20240905071738.3725-1-kerneljasonxing@gmail.com
v4: https://lore.kernel.org/20240830153751.86895-1-kerneljasonxing@gmail.com
v3: https://lore.kernel.org/20240828160145.68805-1-kerneljasonxing@gmail.com
v2: https://lore.kernel.org/20240825152440.93054-1-kerneljasonxing@gmail.com
====================

Link: https://patch.msgid.link/20240909015612.3856-1-kerneljasonxing@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>