freebsd with flexible iflib nic queues
1e35c8564a
for Windows are deserialized miniports. Such drivers maintain their own queues and do their own locking. This particular driver is not deserialized though, and we need special support to handle it correctly. Typically, in the ndis_rxeof() handler, we pass all incoming packets directly to (*ifp->if_input)(). This in turn may cause another thread to run and preempt us, and the packet may actually be processed and then released before we even exit the ndis_rxeof() routine. The problem with this is that releasing a packet calls the ndis_return_packet() function, which hands the packet and its buffers back to the driver. Calling ndis_return_packet() before ndis_rxeof() returns will screw up the driver's internal queues since, not being deserialized, it does no locking. To avoid this problem, if we detect a serialized driver (by checking the attribute flags passed to NdisSetAttributesEx(), we use an alternate ndis_rxeof() handler, ndis_rxeof_serial(), which puts the call to (*ifp->if_input)() on the NDIS SWI work queue. This guarantees the packet won't be processed until after ndis_rxeof_serial() returns. Note that another approach is to always copy the packet data into another mbuf and just let the driver retain ownership of the ndis_packet structure (ndis_return_packet() never needs to be called in this case). I'm not sure which method is faster. |
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| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| installworld_newk | ||
| installworld_oldk | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| README | ||
| UPDATING | ||
| UPDATING.64BTT | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html