every iteration of aac_startio(). This ensures that a command that is
deferred for lack of resources doesn't immediately get retried in the
aac_startio() loop. This avoids an almost certain livelock.
* Spell out some names that were pointlessly abbreviated
* Remove a couple of incidental duplicates
* Harry Truman had no actual middle name. The initial "S" was added to his
name to make him appear more statesmanlike. Therefore it's not usually punctuated.
* Format a couple of actual fortunes to fit into 72 columns
process id, instead of using pid==0. Ie, `ps -p 12,' and `ps -p ,12'
are now errors (instead of being treated like `ps -p 0 -p 12').
Noticed by: Cyrille Lefevre on freebsd-arch
the socket is on an accept queue of a listen socket. This change
renames the flags to SQ_COMP and SQ_INCOMP, and moves them to a new
state field on the socket, so_qstate, as the locking for these flags
is substantially different for the locking on the remainder of the
flags in so_state.
is treated like `ps -t p0', instead of changing it to `ps -T p0'.
Note that `ps t' is still changed to `ps -T', since that is one of
the main reasons for this kludge processing...
Noticed by: Jilles Tjoelker on freebsd-arch
more special situations. This is the code which process `ps blah',
when "blah" does not include a leading '-'.
This change also removes a long-undocumented BACKWARD_COMPATIBILITY
compile-time option, where:
ps -options arg1 arg2
(with no '-' on "arg1" and "arg2") was treated as:
ps -options -N arg1 -M arg2
This also changes `ps' to check for any additional arguments after
processing all the '-'-options, and attempt to use those arguments as
a pid or pidlist. If an extra argument is not a valid pidlist, then
`ps' will print an error and exit. This seems a more generally useful
extension of the kludge-option processing than the -N/-M behavior, and
has fewer confusing side-effects.
Reviewed by: freebsd-arch
It doesn't take 'align' and 'flags' but 'master' instead, which is
a reference to the Master Zone, containing the backing Keg.
Pointed out by: Tim Robbins (tjr)
them to behave the same as if the SS_NBIO socket flag had been set
for this call. The SS_NBIO flag for ordinary sockets is set by
fcntl(fd, F_SETFL, O_NONBLOCK).
Pass the MSG_NBIO flag to the soreceive() and sosend() calls in
fifo_read() and fifo_write() instead of frobbing the SS_NBIO flag
on the underlying socket for each I/O operation. The O_NONBLOCK
flag is a property of the descriptor, and unlike ordinary sockets,
fifos may be referenced by multiple descriptors.
about the risks of enabling raw sockets in prisons.
Because raw sockets can be used to configure and interact
with various network subsystems, extra caution should be
used where privileged access to jails is given out to
untrusted parties. As such, by default this option is disabled.
A few others and I are currently auditing the kernel
source code to ensure that the use of raw sockets by
privledged prison users is safe.
Approved by: bmilekic (mentor)
mbuma is an Mbuf & Cluster allocator built on top of a number of
extensions to the UMA framework, all included herein.
Extensions to UMA worth noting:
- Better layering between slab <-> zone caches; introduce
Keg structure which splits off slab cache away from the
zone structure and allows multiple zones to be stacked
on top of a single Keg (single type of slab cache);
perhaps we should look into defining a subset API on
top of the Keg for special use by malloc(9),
for example.
- UMA_ZONE_REFCNT zones can now be added, and reference
counters automagically allocated for them within the end
of the associated slab structures. uma_find_refcnt()
does a kextract to fetch the slab struct reference from
the underlying page, and lookup the corresponding refcnt.
mbuma things worth noting:
- integrates mbuf & cluster allocations with extended UMA
and provides caches for commonly-allocated items; defines
several zones (two primary, one secondary) and two kegs.
- change up certain code paths that always used to do:
m_get() + m_clget() to instead just use m_getcl() and
try to take advantage of the newly defined secondary
Packet zone.
- netstat(1) and systat(1) quickly hacked up to do basic
stat reporting but additional stats work needs to be
done once some other details within UMA have been taken
care of and it becomes clearer to how stats will work
within the modified framework.
From the user perspective, one implication is that the
NMBCLUSTERS compile-time option is no longer used. The
maximum number of clusters is still capped off according
to maxusers, but it can be made unlimited by setting
the kern.ipc.nmbclusters boot-time tunable to zero.
Work should be done to write an appropriate sysctl
handler allowing dynamic tuning of kern.ipc.nmbclusters
at runtime.
Additional things worth noting/known issues (READ):
- One report of 'ips' (ServeRAID) driver acting really
slow in conjunction with mbuma. Need more data.
Latest report is that ips is equally sucking with
and without mbuma.
- Giant leak in NFS code sometimes occurs, can't
reproduce but currently analyzing; brueffer is
able to reproduce but THIS IS NOT an mbuma-specific
problem and currently occurs even WITHOUT mbuma.
- Issues in network locking: there is at least one
code path in the rip code where one or more locks
are acquired and we end up in m_prepend() with
M_WAITOK, which causes WITNESS to whine from within
UMA. Current temporary solution: force all UMA
allocations to be M_NOWAIT from within UMA for now
to avoid deadlocks unless WITNESS is defined and we
can determine with certainty that we're not holding
any locks when we're M_WAITOK.
- I've seen at least one weird socketbuffer empty-but-
mbuf-still-attached panic. I don't believe this
to be related to mbuma but please keep your eyes
open, turn on debugging, and capture crash dumps.
This change removes more code than it adds.
A paper is available detailing the change and considering
various performance issues, it was presented at BSDCan2004:
http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf
Please read the paper for Future Work and implementation
details, as well as credits.
Testing and Debugging:
rwatson,
brueffer,
Ketrien I. Saihr-Kesenchedra,
...
Reviewed by: Lots of people (for different parts)
Add two additional pairs of assertions, one at the end of the NFS
server event loop, and one one exit from the NFS daemon, that
assert that if debug.mpsafenet is enabled, Giant is not held, and
that if it is not enabled, Giant will be held. This is intended
to support debugging scenarios where Giant is "leaked" during NFS
processing.
my Elektor card. Note that the hints are necessary to specify the
IO base of the pcf chip. This enables to check the IO base when the
probe routine is called during ISA enumeration.
The interrupt driven code is mixed with polled mode, which is wrong
and produces supposed spurious interrupts at each access. I still have
to work on it.
