6f3e0bcd3d
Most of the nodes in the general sysctl tree will be managed directly by the MIB service, which obtains the necessary information as needed. However, in certain cases, it makes more sense to let another service manage a part of the sysctl tree itself, in order to avoid replicating part of that other service in the MIB service. This patch adds the basic support for such delegation: remote services may now register their own subtrees within the full sysctl tree with the MIB service, which will then forward any sysctl(2) requests on such subtrees to the remote services. The system works much like mounting a file system, but in addition to support for shadowing an existing node, the MIB service also supports creating temporary mount point nodes. Each have their own use cases. A remote "kern.ipc" would use the former, because even when such a subtree were not mounted, userland would still expect some of its children to exist and return default values. A remote "net.inet" would use the latter, as there is no reason to precreate nodes for all possible supported networking protocols in the MIB "net" subtree. A standard remote MIB (RMIB) implementation is provided for services that wish to make use of this functionality. It is essentially a simplified and somewhat more lightweight version of the MIB service's internals, and works more or less the same from a programmer's point of view. The most important difference is the "rmib" prefix instead of the "mib" prefix. Documentation will hopefully follow later. Overall, the RMIB functionality should not be used lightly, for several reasons. First, despite being more lightweight than the MIB service, the RMIB module still adds substantially to the code footprint of the containing service. Second, the RMIB protocol not only adds extra IPC for sysctl(2), but has also not been optimized for performance in other ways. Third, and most importantly, the RMIB implementation also several limitations. The main limitation is that remote MIB subtrees must be fully static. Not only may the user not create or destroy nodes, the service itself may not either, as this would clash with the simplified remote node versioning system and the cached subtree root node child counts. Other limitations exist, such as the fact that the root of a remote subtree may only be a node-type node, and a stricter limit on the highest node identifier of any child in this subtree root (currently 4095). The current implementation was born out of necessity, and therefore it leaves several improvements to future work. Most importantly, support for exit and crash notification is missing, primarily in the MIB service. This means that remote subtrees may not be cleaned up immediately, but instead only when the MIB service attempts to talk to the dead remote service. In addition, if the MIB service itself crashes, re-registration of remote subtrees is currently left up to the individual RMIB users. Finally, the MIB service uses synchronous (sendrec-based) calls to the remote services, which while convenient may cause cascading service hangs. The underlying protocol is ready for conversion to an asynchronous implementation already, though. A new test set, testrmib.sh, tests the basic RMIB functionality. To this end it uses a test service, rmibtest, and also reuses part of the existing test87 MIB service test. Change-Id: I3378fe04f2e090ab231705bde7e13d6289a9183e |
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| .. | ||
| lists | ||
| attrs | ||
| checkflist | ||
| comments | ||
| culldeps | ||
| deps | ||
| descrs | ||
| getdirs.awk | ||
| join.awk | ||
| listpkgs | ||
| Makefile | ||
| makeflist | ||
| makeobsolete | ||
| makeplist | ||
| makesrctars | ||
| makesums | ||
| maketars | ||
| metalog.subr | ||
| mkvars.mk | ||
| README | ||
| regpkg | ||
| regpkgset | ||
| sets.subr | ||
| sort-list | ||
| syspkgdeps | ||
| TODO | ||
| versions | ||
# $NetBSD: README,v 1.13 2013/08/06 22:33:59 soren Exp $
the scripts should be run from the directory where they reside.
makeflist: output the list of files that should be in a
distribution, according to the contents of the
'lists' directory.
checkflist: check the file list (as internally generated
by makeflist) against the tree living in $DESTDIR.
(that tree should be made with 'make distribution'.)
maketars: make tarballs of the various sets in the distribution,
based on the contents of the lists, the tree in
$DESTDIR, and put the tarballs in $RELEASEDIR.
Note that this script _doesn't_ create the 'secr'
distribution, because (for now) it requires
manual intervention to get the binaries right...
(i'll add another script to create that dist, later.)
what's in 'lists':
lists describing file sets. There are two sets of lists per file
set: machine dependent and machine-independent files. (there's
also another file in the 'man' dir, which is used by the 'man'
and 'misc' sets, but that's explained later.)
There is one machine-independent file, named "mi". There are
N machine-dependent files (one per architecture), named "md.${ARCH}".
the sets are as follows:
base: the base binary set. excludes everything described
below.
comp: compiler tools. All of the tools relating to C, C++,
and FORTRAN (yes, there are two!) that are in the
tree. This includes includes, the linker, tool chain,
and the .a versions of the libraries. (obviously,
base includes ldd, ld.so, and the shared versions.
base also includes 'cpp', because that's used by X11.)
includes the man pages for all the binaries contained
within. Also, includes all library and system call
manual pages.
debug: Debugging libraries (_g.a/MKDEBUGLIB) and (.debug/MKDEBUG)
binaries.
etc: /etc, and associated files (/var/cron/tabs, /root,
etc.). things that shouldn't be blindly reinstalled
on an upgrade.
games: the games and their man pages.
man: all of the man pages for the system, except those
listed elsewhere (e.g. in comp, games, misc, text).
Includes machine-dependent man pages for this CPU.
misc: share/dict, share/doc, and the machine-dependent
man pages for other CPUs which happen to always
be installed.
modules: stand/${MACHINE}/${OSRELEASE}/modules kernel modules
tests: unit, regression, integration and stress tests for the
whole system.
text: text processing tools. groff and all of its friends.
includes man pages for all bins contained within.
Each set must contain "./etc/mtree/set.<set name>" within the mi
list. Failure to add this will break unprivileged builds.