When a transition from link alive to link dead configuration or vice
versa occurs, notify any upstream and / or downstream peers using
NGM_FLOW messagges.
Link state notification using NGM_FLOW messages is modelled around
around already existing code in ng_ether.c.
MFC after: 3 days
virtual ifnets more realistically mimic physical ethernet interfaces.
The main motivation behind this change is to allow for ng_eiface(4)
interfaces to participate in STP if_bridge(4) configurations.
When announcing link status changes, switch to the vnet to which the
ifnet belongs, since it is possible for ng_eiface ifnets to be assigned
to a vnet different from the one in which its netgraph node resides.
MFC after: 3 days
Specifically, a critical_exit() call that drops the nesting level to zero
has a brief window where the pending preemption flag is set and the
nesting level is set to zero. This is done purposefully to avoid races
where a preemption scheduled by an interrupt could be lost otherwise (see
revision 144777). However, this does mean that if an interrupt fires
during this window and enters and exits a critical section, it may preempt
from the interrupt context. This is generally fine as the interrupt code
is careful to arrange critical sections so that they are not exited until
it is safe to preempt (e.g. interrupts EOI'd and masked if necessary).
However, the SMP rendezvous IPI handler does not quite follow this rule,
and in general a rendezvous can never be preempted. Rendezvous handlers
are also not permitted to schedule threads to execute, so they will not
typically trigger preemptions. SMP rendezvous handlers may use
spinlocks (carefully) such as the rm_cleanIPI() handler used in rmlocks,
but using a spinlock also enters and exits a critical section. If the
interrupted top-half code is in the brief window of critical_exit() where
the nesting level is zero but a preemption is pending, then releasing the
spinlock can trigger a preemption. Because we know that SMP rendezvous
handlers can never schedule a thread, we know that a critical_exit() in
an SMP rendezvous handler will only preempt in this edge case. We also
know that the top-half thread will happily handle the deferred preemption
once the SMP rendezvous has completed, so the preemption will not be lost.
This makes it safe to employ a workaround where we use a nested critical
section in the SMP rendezvous code itself around rendezvous action
routines to prevent any preemptions during an SMP rendezvous. The
workaround intentionally avoids checking for a deferred preemption
when leaving the critical section on the assumption that if there is a
pending preemption it will be handled by the interrupted top-half code.
Submitted by: mlaier (variation specific to rm_cleanIPI())
Obtained from: Isilon
MFC after: 1 week
now the preferred typical return value from a probe routine. Discourage
the use of 0 (BUS_PROBE_SPECIFIC) as it should be used very rarely.
Point the reader to the DEVICE_PROBE(9) manpage for more detailed notes
on possible probe return values.
Submitted by: Philip Soeberg philip-dev of soeberg net
be represented:
- A single policy namespace is defined, consisting of four possible
policies: "default" to use the global default, "deferred" to force
deferred dispatch, "direct" to employ direct dispatch where possible, and
"hybrid" which makes a dynamic decision based on CPU affinity, ordering,
etc. Routines are implemented to convert between strings and an integer
namespace.
- A new global variable, netisr_dispatch_policy, subsumes existing global
variables for direct dispatch, forced direct dispatch, etc, and is used
for explicit policy interpretation and composition. Old variables remain
so that they can be exported by legacy sysctls for use by old netstat(1)
binaries. A new sysctl and tunable, netisr.dispatch.policy, accepts the
above strings for specifying a global policy default.
- The protocol registration structure, netisr_handler, grows an nh_dispatch
field, which accepts a per-policy policy override. The default value is
'0', which corresponds to "default", meaning that protocols will accept
the global default policy unless otherwise specified.
- Policies are now interpreted and composed explicitly at various points in
packet dispatch; protocol policies override global policies.
- Protocols grow the ability to express a non-opinion about affinity even
when implenting m2cpuid by returning NETISR_CPUID_NONE. In that case, the
framework falls back on source ordering, rather than simply using the
current CPU.
These changes are in support of allowing link layer re-dispatch based on
RSS or similar hashes provided by NICs, especially in the case where the
number of hardware receive queues matches hardware core count, rather than
hardware thread count, requiring further software redistributeon. (i.e.,
on RMI XLR).
MFC after: 3 weeks
Reviewed by: bz
Sponsored by: Juniper Networks, Inc.
Alexander Best (arundel@).
For clang, -fdiagnostics-show-option is enabled by default, but for gcc it
isn't. This option will report which -W* flag was responsible for triggering
a certain warning. This will bring gcc warnings closer to the ones clang emits
and might also help developers track down tinderbox failures a bit quicker.
Submitted by: arundel
on top of epair(4) virtual interfaces, since there's no physical
hardware associated with epair interfaces which would imply any
constraints on MTU sizes.
MFC after: 3 days
by borrowing the skeleton of if_media manipulation and reporting
code from if_lagg(4). The main motivation behind this change is
to allow for epair(4) interfaces to participate in STP if_bridge(4)
configurations.
Reviewed by: bz
MFC after: 3 days
This should hopefully make it clearer to developers what is going on
and when TPC is being hacked on, make it obvious why it isn't working for
series 1, 2, 3.
I won't flip on setting TX power for TX series 1, 2, 3 until I've done
some further testing with Kite to ensure it doesn't break anything.
(Before people ask - yes, TPC is only needed for 5ghz regdomains and
yes, Kite is a 2.4ghz only chip, but there are potential use cases
for 2ghz TPC. I just need to sit down and ensure it's supported and
functional.)
control the antenna control bits for the four TX series and the
TPC settings for TX series 1, 2, 3.
The specifics:
* The TPC setting for TX series 0 is handled in ctl0.
* TPC is currently disabled, so the per-packet TX power is
set via the global per-rate TX power register, not per packet.
* The antenna control bits don't matter for AR5416 and later
so they should stay 0 (which they currently do); they may
be set for Kite but as there's no TX diversity supported
at the moment (it requires the NIC to be built with an
external antenna switch, matching how antenna diversity
is done on legacy NICs), so again keep them 0.
This is in preparation for supporting per-rate TPC on the
AR5416 and later. The Kite (and soon to come Kiwi) code
sets ctl8-11 to 0x0, which doesn't have any effect at
the moment. When TPC is enabled it would result in the
second, third and fourth TX series attmpts to be done with
a TX power of 0. This commit doesn't change that; it'll
be followed up with some commits to properly set the TPC
registers appropriately.
Fix arguments passing to _long() version of atomic function for mips.
The native implementation is bogus in that regard and offers the same
problem solved for powerpc as r222198, but mips' guys just wanted a
small and self-contained patch for mips rather than rewriting the
whole support.
Reviewed by: art, imp
Tested by: gonzo
MFC after: 2 weeks
requests as well as number of activemap updates.
Number of BIO_WRITEs and activemap updates are especially interesting, because
if those two are too close to each other, it means that your workload needs
bigger number of dirty extents. Activemap should be updated as rarely as
possible.
MFC after: 1 week
quality to 950. HPET on modern platforms usually have better resolution and
lower latency than ACPI timer. Effectively this changes default timecounter
hardware from ACPI-fast to HPET by default when both are available.
Discussed with: avg
bits of the register is used for other purposes such that clearing
these bits resulted in unexpected results such as corrupted RX
frames or missing LE status updates. For old controllers like
Yukon EC it had no effect but it caused all kind of troubles on
Yukon Supreme.
This change shall improve stability of controllers like Yukon
Ultra, Ultra2, Extreme, Optima and Supreme.
reworking of inpcbinfo locking:
(1) Convert inpcb reference counting from manually manipulated integers to
the refcount(9) KPI. This allows the refcount to be managed atomically
with an inpcb read lock rather than write lock, or even with no inpcb
lock at all. As a result, in_pcbref() also no longer requires an inpcb
lock, so can be performed solely using the lock used to look up an
inpcb.
(2) Shift more inpcb freeing activity from the in_pcbrele() context (via
in_pcbfree_internal) to the explicit in_pcbfree() context. This means
that the inpcb refcount is increasingly used only to maintain memory
stability, not actually defer the clean up of inpcb protocol parts.
This is desirable as many of those protocol parts required the pcbinfo
lock, which we'd like not to acquire in in_pcbrele() contexts. Document
this in comments better.
(3) Introduce new read-locked and write-locked in_pcbrele() variations,
in_pcbrele_rlocked() and in_pcbrele_wlocked(), which allow the inpcb to
be properly unlocked as needed. in_pcbrele() is a wrapper around the
latter, and should probably go away at some point. This makes it
easier to use this weak reference model when holding only a read lock,
as will happen in the future.
This may well be safe to MFC, but some more KBI analysis is required.
Reviewed by: bz
MFC after: 3 weeks
Sponsored by: Juniper Networks, Inc.
in_pcb_lport(), in_pcblookup_local(), and in_pcblookup_hash(), and similarly
for IPv6 functions. In the future, we would like to support other flags
relating to locking strategy.
This change doesn't appear to modify the KBI in practice, as callers already
passed in INPLOOKUP_WILDCARD rather than a simple boolean.
MFC after: 3 weeks
Reviewed by: bz
Sponsored by: Juniper Networks, Inc.
(1) Add a locking guide for inpcbinfo.
(2) Annotate inpcbinfo fields with synchronisation information; not all
annotations are 100% satisfactory.
(3) Reorder inpcbinfo fields so that the lock is at the head of the
structure, and close to fields it protects.
(4) Sort fields that will eventually be hashlock/pcbgroup-related together
even though they remain locked by ipi_lock for now.
Reviewed by: bz
Sponsored by: Juniper Networks
X-MFC after: KBI analysis required
When we are operating on a symbolic link pointing to an existing
file, bail out by default, but go ahead if -f is specified.
Submitted by: arundel
MFC after: 2 weeks
Increase the size of cg_count in order to enable usage of > 127 CPUs.
cg_children is also bumped in order to keep the structure naturally
padded, even if this is not strictly necessary.
Submitted and tested by: sbruno
Rewrite atomic operations for powerpc in order to achieve the following:
- Produce a type-clean implementation (in terms of functions arguments
and returned values) for the primitives.
- Fix errors with _long() atomics where they ended up with the wrong
arguments to be accepted.
- Follow the sys/type.h specifics that define the numbered types starting
from standard C types.
- Let _ptr() version to not auto-magically cast arguments, but leave
the burden on callers, as _ptr() atomic is intended to be used
relatively rarely.
Fix cfi in order to support the latest point.
In collabouration with: bde
Tested by: andreast, nwhitehorn, jceel
MFC after: 2 weeks
