Date: Mon, 10 Oct 2016 14:09:01 +0300 From: Slawa Olhovchenkov <slw@zxy.spb.ru> To: John Baldwin <jhb@FreeBSD.org> Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: Re: svn commit: r306661 - in stable/11/sys/dev/cxgbe: . tom Message-ID: <20161010110901.GH6177@zxy.spb.ru> In-Reply-To: <201610032315.u93NFiHE057529@repo.freebsd.org> References: <201610032315.u93NFiHE057529@repo.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Oct 03, 2016 at 11:15:44PM +0000, John Baldwin wrote: > Author: jhb > Date: Mon Oct 3 23:15:44 2016 > New Revision: 306661 > URL: https://svnweb.freebsd.org/changeset/base/306661 > > Log: > MFC 303405: Add support for zero-copy aio_write() on TOE sockets. > > AIO write requests for a TOE socket on a Chelsio T4+ adapter can now > DMA directly from the user-supplied buffer. This is implemented by > wiring the pages backing the user-supplied buffer and queueing special > mbufs backed by raw VM pages to the socket buffer. The TOE code > recognizes these special mbufs and builds a sglist from the VM page > array associated with the mbuf when queueing a work request to the TOE. > > Because these mbufs do not have an associated virtual address, m_data > is not valid. Thus, the AIO handler does not invoke sosend() directly > for these mbufs but instead inlines portions of sosend_generic() and > tcp_usr_send(). > > An aiotx_buffer structure is used to describe the user buffer (e.g. > it holds the array of VM pages and a reference to the AIO job). The > special mbufs reference this structure via m_ext. Note that a single > job might be split across multiple mbufs (e.g. if it is larger than > the socket buffer size). The 'ext_arg2' member of each mbuf gives an > offset relative to the backing aiotx_buffer. The AIO job associated > with an aiotx_buffer structure is completed when the last reference to > the structure is released. > > Zero-copy aio_write()'s for connections associated with a given > adapter can be enabled/disabled at runtime via the > 'dev.t[45]nex.N.toe.tx_zcopy' sysctl. > > Sponsored by: Chelsio Communications Do you have any public available application patches for support this? May be nginx?
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20161010110901.GH6177>