interface address, blow the address away again before returning the
error.
In in_ifinit(), if we get an error from rtinit() and we've also got
a destination address, return the error rather than masking EEXISTS.
Failing to create a host route when configuring an interface should
be treated as an error.
pointless and would be inadequate for SMP systems. We will rely on the
VM system's locks to serialise this for now.
* Change pmap_remove() so that if the range being removed is larger than
the number of pages mapped by the pmap, we iterate over the currently
mapped pages instead of over the virtual address range. This should
make a difference when removing large virtual address ranges from an
address space.
mbuf allocation fails, and fix (i hope) a couple of style bugs.
I believe these printf() are extremely dangerous because now they can
occur on every incoming packet and are not rate limited. They were
meant to warn the sysadmin about lack of resources, but now they
can become a nice way to panic your system under load.
Other drivers (e.g. the fxp driver) have nothing like this.
There is a pending discussion on putting this kind of warnings
elsewhere, and I hope we can fix this soon.
underlying unaligned bcopy) on incoming packets that are already
available (albeit unaligned) in a buffer.
The performance improvement varies, depending on CPU and memory
speed, but can be quite large especially on slow CPUs. I have seen
over 50% increase on forwarding speed on the sis driver for the
486/133 (embedded systems), which does exactly the same thing.
The behaviour is controlled by a sysctl variable, hw.dc_quick which
defaults to 1. Set it to 0 to restore the old behaviour.
After running a few experiments (in userland, though) I am convinced
that doing the m_devget() is detrimental to performance in almost
all cases.
Even if your CPU has degraded performance with misaligned data,
the bcopy() in the driver has the same overhead due to misaligment
as the one that you save in the uiomove(), plus you do one extra
copy and pollute the cache.
But more often than not, you do not even have to touch the payload,
e.g. when you are forwarding packets, and even in the often-cited
case of NFS, you often end up passing a pointer to the payload to
the disk controller.
In any case, you can play with the sysctl variable to toggle between
the two behaviours, and see if it makes a difference.
MFC-after: 3 days
readability.
o Conditionalize only the SYSCTL definitions for the regression
tree, not the variables itself, decreasing the number of #ifdef
REGRESSIONs scattered in kern_mib.c, and making the code more
readable.
Sponsored by: DARPA, NAI Labs
have alignment problems.
On small boxes (e.g. the net4501 from Soekris, featuring a 486/133)
this provides huge performance benefits: the peak forwarding rate
with avg.sized packets goes up by 50-70% because of this change
alone. Faster CPUs might benefit less from this change, but in any
case the CPU has better things to do than waste time on useless
memory-to-memory copies.
Several drivers (for Tulip-like cards) might benefit from a similar
change.
Right now the new behaviour is controlled by a sysctl variable,
hw.sis_quick which defaults to 1 (on), you can set it to 0 to
reintroduce the old behaviour (and compare the results). The
variable is only there to show how much you can gain with this
change, it will go away soon.
Also, slightly simplify the code to initialize the ring buffers,
and remove a couple of dangerous printf's which could trigger on
any packet in case of mbuf shortage.
MFC-after: 3 days
received on an interface without an IP address, try to find a
non-loopback AF_INET address to use. If that fails, drop it.
Previously, we used the address at the top of the in_ifaddrhead list,
which didn't make much sense, and would cause a panic if there were no
AF_INET addresses configured on the system.
PR: 29337, 30524
Reviewed by: ru, jlemon
Obtained from: NetBSD
respects locks. Before SMPng, one was able to call psignal()
using the "call" command, but this is no longer possible because it
does not respect locks by itself. This is very useful when one has
gotten their machine into a state where it is impossible to spawn
ps/kill or su to root.
In this case, respecting locks essentially means trying to aquire the
proc lock before calling psignal(). We can't block in the debugger,
so if trylock fails, the operation fails. This also means that we
can't use pfind(), since that will attempt to lock the process for us.
Reviewed by: jhb
idle and the driver would not detect the event, requiring userland
to cycle the interface to bring it up again.
The fix consists in adding SIS_IMR_RX_IDLE to the interrupt mask and
add a command in sis_intr() to restart the receiver when this happens.
While at it, make the test of status bits more efficient.
for passive mode data connections (PASV/EPSV -> 227/229). Well,
the actual punching happens a bit later, when the aliasing link
becomes fully specified.
Prodded by: Danny Carroll <dannycarroll@hotmail.com>
MFC after: 1 week
