freebsd with flexible iflib nic queues
53555c6fe6
Make state transitions of a thread on a mutex queue atomic (with respect to other threads and signal handlers). This includes: o Introduce two functions to implement atomicity with respect to other threads and signal handlers. Basically, _thread_critical_enter() locks the calling thread and blocks signals. _thread_critical_exit() unblocks signals and unlocks the thread. o Introduce two new functions: get_muncontested() locks a mutex that is not owned by another thread. get_mcontested() places a thread on a contested mutex's queue, taking care to use the _thread_critical_enter/exit functions to protect thread state. o Modify mutex_unlock_common() to also protect state transitions. In this case it needs the cooperation of mutex_queue_deq(), which must return with the thread locked and signals disabled *before* it takes the thread off the queue. Combine _pthread_mutex_lock() and _pthread_mutex_trylock() into one function: mutex_lock_common(), that can handle both cases. Its behaviour is controlled by an argument, int nonblock, which if not zero means do not attempt to acquire a contested mutex if the uncontested case fails. BTW, when I write about contested and uncontested mutexes, I'm writing about it from the application's point of view. I'm not writing about internal locking of pthread_mutex->lock, which is achieved differently. While internal mutex locking is mostly done, there's still a bit more work left in this area. Approved by: markm/mentor, re/blanket libthr Reviewed by: jeff (slightly diff. revision) |
||
|---|---|---|
| bin | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| 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 ``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