From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jakub Kicinski Date: Thu, 27 Jun 2019 14:25:34 -0700 Subject: [Intel-wired-lan] [PATCH 00/11] XDP unaligned chunk placement support In-Reply-To: References: <20190620083924.1996-1-kevin.laatz@intel.com> Message-ID: <20190627142534.4f4b8995@cakuba.netronome.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On Thu, 27 Jun 2019 12:14:50 +0100, Laatz, Kevin wrote: > On the application side (xdpsock), we don't have to worry about the user > defined headroom, since it is 0, so we only need to account for the > XDP_PACKET_HEADROOM when computing the original address (in the default > scenario). That assumes specific layout for the data inside the buffer. Some NICs will prepend information like timestamp to the packet, meaning the packet would start at offset XDP_PACKET_HEADROOM + metadata len.. I think that's very limiting. What is the challenge in providing aligned addresses, exactly?