Stanislav Fomichev
5ef44b3cb4
Commit86e25f40aa("net: napi: Add napi_config") moved napi->napi_id assignment to a later point in time (napi_hash_add_with_id). This breaks __xdp_rxq_info_reg which copies napi_id at an earlier time and now stores 0 napi_id. It also makes sk_mark_napi_id_once_xdp and __sk_mark_napi_id_once useless because they now work against 0 napi_id. Since sk_busy_loop requires valid napi_id to busy-poll on, there is no way to busy-poll AF_XDP sockets anymore. Bring back the ability to busy-poll on XSK by resolving socket's napi_id at bind time. This relies on relatively recent netif_queue_set_napi, but (assume) at this point most popular drivers should have been converted. This also removes per-tx/rx cycles which used to check and/or set the napi_id value. Confirmed by running a busy-polling AF_XDP socket (github.com/fomichev/xskrtt) on mlx5 and looking at BusyPollRxPackets from /proc/net/netstat. Fixes:86e25f40aa("net: napi: Add napi_config") Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20250109003436.2829560-1-sdf@fomichev.me Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.