alignment restrictive, and help performance on some ethernet cards which
currently copy the entire packet a couple bytes to get the packet aligned
properly...
Wordsmithing by: dwhite
Obtained from: NetBSD (code only)
I'll clean it up later: rwatson
is the highest acceptable value for the ending of the resource being
allocated. One could also believe that it is the highest starting
value of the resource. The code definitely expects the former, but I
could find no documentation of this apart from TFSC.
clock time to uptime because wall clock time may go backwards.
This is a change in the API which will impact SNMP agents who are using
ifi_epoch to set RFC2233's ifCounterDiscontinuityTime. None are know to
exist today. This will not impact applications that are using the
<index, epoch> tuple to verify interface uniqueness except that it
eliminates a race which could lead to a false assumption of uniqueness.
Because this is a behavior change, bump __FreeBSD_version.
Discussed with: re (jhb, scottl)
MFC after: 3 days
Pointed out by: pkh (way back at EuroBSDCon)
Pointy hat: brooks
holding the mutex, say it will "block". Later in this manual page
we say that sleeping while holding a mutex isn't allowed, and this
can be confusing.
Submitted by: jhb
with other profiling and debugging options, such as INVARIANTS, WITNESS,
kernel profiling, etc. They all interfere with each other nastily and
will generate fairly useless results.
callout is first initialised, using a new function callout_init_mtx().
The callout system will acquire this mutex before calling the callout
function and release it on return.
In addition, the callout system uses the mutex to avoid most of the
complications and race conditions inherent in asynchronous timer
facilities, so mutex-protected callouts have much simpler semantics.
As long as the mutex is held when invoking callout_stop() or
callout_reset(), then these functions will guarantee that the callout
will be stopped, even if softclock() had already begun to process
the callout.
Existing Giant-locked callouts will automatically pick up the new
race-free semantics. This should close a number of race conditions
in the USB code and probably other areas of the kernel too.
There should be no change in behaviour for "MP-safe" callouts; these
still need to use the techniques mentioned in timeout(9) to avoid
race conditions.
when using the callout subsystem. Show how the callout_pending(),
callout_active() and callout_deactivate() macros can be used to
achieve simpler race-free callout semantics in many situations.
location of a PCI device in the system chassis.
Remove the note about PAE.
Update document date.
Update my email address.
Update copyright.
MFC after: 1 week
