freebsd kernel with SKQ
21a6592999
mtx interface for NDIS_LOCK/UNLOCK. This should result in less CPU utilization on behalf of the ndis driver. Additionally, this commit also fixes a potential LOR in the ndis_tick code, by not locking inside the ndis_tick function, but instead delegating that work to the helpers called through IoQueueWorkItem. The way that this is currently set up for NDIS prevents us from simply implementing a callout_init_mtx mechanism. However, the helper functions that handle the various timeout cases implement fine-grained locking using the spinlocks provided by the NDIS-compat layer, and using the mtx that is added with this commit. This leaves the following ndis_softc members operated on in ndis_tick in an unlocked context: * ndis_hang_timer - Only modified outside of ndis_tick once, before the first callout_reset to schedule ndis_tick * ifp->if_oerrors - Only incremented in two places, which should be an atomic op * ndis_tx_timer - Assigned to 5 (when guaranteed to be 0) or 0 (in txeof), to indicate to ndis_tick what to do. This is the only member of which I was suspicious for needing the NDIS_LOCK here. My testing (and another's) have been fine so far. * ndis_stat_callout - Only uses a simple set of callout routines, callout_reset only called by ndis_tick after the initial reset, and then callout_drain is used exactly once in shutdown code. The benefit is that ndis_tick doesn't acquire NDIS_LOCK unless one of the timeout conditions is flagged, and it still obeys the locking order semantics that are dictated by the NDIS layer at the moment. I have been investigating a more thorough s/spinlock/mtx/ of the NDIS layer, but the simplest naive approach (replace KeAcquireSpinLock with an mtx implementation) has anti-succeeded for me so far. This is a good first step though. Tested by: onemda@gmail.com Reviewed by: current@, jhb, thompsa Proposed by: jhb |
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bin | ||
cddl | ||
contrib | ||
crypto | ||
etc | ||
games | ||
gnu | ||
include | ||
kerberos5 | ||
lib | ||
libexec | ||
release | ||
rescue | ||
sbin | ||
secure | ||
share | ||
sys | ||
tools | ||
usr.bin | ||
usr.sbin | ||
COPYRIGHT | ||
LOCKS | ||
MAINTAINERS | ||
Makefile | ||
Makefile.inc1 | ||
ObsoleteFiles.inc | ||
README | ||
UPDATING |
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 ``world'' target should only be used in cases where the source tree has not changed from the currently running version. See: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html for more information, including setting make(1) variables. 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. rescue Build system for statically linked /rescue utilities. 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