From Jake:
"The iflib_fl_setup() function tries to pick various buffer sizes based
on the max_frame_size value defined by the parent driver. However, this
code was wrapped under CONTIGMALLOC_WORKS, which was never actually
defined anywhere.
This same code pattern was used in if_em.c, likely trying to match
what iflib uses.
Since CONTIGMALLOC_WORKS is not defined, remove this dead code from
iflib_fl_setup and if_em.c
Given that various iflib drivers appear to be using a similar
calculation, it might be worth making this buffer size a value that the
driver can peek at in the future."
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D19199
r241119 that's performed globally by device_attach(9).
- As for the EM-class of devices, em(4) supports multiple queues
and MSI-X respectively only with 82574 devices. However, since
the conversion to iflib(4), em(4) relies on the interrupt type
fallback mechanism, i. e. MSI-X -> MSI -> INTx, of iflib(4) to
figure out the interrupt type to use for the EM-class (as well
as the IGB-class) of MACs. Moreover, despite the datasheet for
82583V not mentioning any support of MSI-X, there actually are
82583V devices out there that report a varying number of MSI-X
messages as supported. The interrupt type fallback of iflib(4)
is causing two failure modes depending on the actual number of
MSI-X messages supported for such instances of 82583V:
1) With only one MSI-X message supported, none is left for the
RX/TX queues as that one message gets assigned to the admin
interrupt. Worse, later on - which will be addressed with a
separate fix - iflib(4) interprets that one messages as MSI
or INTx to be set up, but fails to actually do so as it has
previously called pci_alloc_msix(9). [1, 2]
2) With more message supported, their distribution is okay but
then em_if_msix_intr_assign() doesn't work for 82583V, with
the interface being left in a non-working state, too. [3]
Thus, let em_if_attach_pre() indicate to iflib(4) to try MSI-X
with 82574 only, and at most MSI for the remainder of EM-class
devices.
While at it, remove "try_second_bar" as it's polarity inverted
and not actually needed.
- Remove code from em_if_timer() that effectively is a NOP since
the conversion to iflib(4) ("trigger" is no longer read).
While at it, let the comment for em_if_timer() reflect reality
after said conversion.
- Implement an ifdi_watchdog_reset method which only updates the
em(4) "watchdog_events" counter but doesn't perform any reset,
so that the em(4) "watchdog_timeouts" SYSCTL (iflib(4) doesn't
provide a counterpart) reflects reality and these timeouts add
to IFCOUNTER_OERRORS again after the iflib(4) conversion.
- Remove the "mbuf_defrag_fail" and "tx_dma_fail" SYSCTLS; since
the iflib(4) conversion, associated counters are disconnected,
but iflib(4) provides "mbuf_defrag_failed" and "tx_map_failed"
respectively as equivalents.
- Move the description preceding lem_smartspeed() to the correct
spot before em_reset() and bring back appropriate comments for
{igb,em}_initialize_rss_mapping() and lem_smartspeed() lost in
the iflib(4) conversion.
- Adapt some other function descriptions and INIT_DEBUGOUT() use
to match reality after the iflib(4) conversion.
- Put the debugging message of em_enable_vectors_82574() (missed
in r343578) under bootverbose, too.
PR: 219428 [1], 235246 [2], 235147 [3]
Reviewed by: erj (previous version)
Differential Revision: https://reviews.freebsd.org/D19108
When configured with more tx queues than rx queues,
em_if_msix_intr_assign() was incorrectly routing the tx event
interrupts.
Reviewed by: erj, marius
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19070
bus_teardown_intr(9) before pci_release_msi(9).
- Ensure that iflib(4) and associated drivers pass correct RIDs to
bus_release_resource(9) by obtaining the RIDs via rman_get_rid(9)
on the corresponding resources instead of using the RIDs initially
passed to bus_alloc_resource_any(9) as the latter function may
change those RIDs. Solely em(4) for the ioport resource (but not
others) and bnxt(4) were using the correct RIDs by caching the ones
returned by bus_alloc_resource_any(9).
- Change the logic of iflib_msix_init() around to only map the MSI-X
BAR if MSI-X is actually supported, i. e. pci_msix_count(9) returns
> 0. Otherwise the "Unable to map MSIX table " message triggers for
devices that simply don't support MSI-X and the user may think that
something is wrong while in fact everything works as expected.
- Put some (mostly redundant) debug messages emitted by iflib(4)
and em(4) during attachment under bootverbose. The non-verbose
output of em(4) seen during attachment now is close to the one
prior to the conversion to iflib(4).
- Replace various variants of spelling "MSI-X" (several in messages)
with "MSI-X" as used in the PCI specifications.
- Remove some trailing whitespace from messages emitted by iflib(4)
and change them to consistently start with uppercase.
- Remove some obsolete comments about releasing interrupts from
drivers and correct a few others.
Reviewed by: erj, Jacob Keller, shurd
Differential Revision: https://reviews.freebsd.org/D18980
From Jake:
In r341156 ("Fix first-packet completion", 2018-11-28) a hack to work
around a delta calculation determining how many descriptors were used
was added to ixl_isc_tx_credits_update_dwb.
The same fix was also applied to the em and igb drivers in r340310, and
to ix in r341156.
The hack checked the case where prev and cur were equal, and then added
one. This works, because by the time we do the delta check, we already
know there is at least one packet available, so the delta should be at
least one.
However, it's not a complete fix, and as indicated by the comment is
really a hack to work around the real bug.
The real problem is that the first time that we transmit a packet,
tx_cidx_processed will be set to point to the start of the ring.
Ultimately, the credits_update function expects it to point to the
*last* descriptor that was processed. Since we haven't yet processed any
descriptors, pointing it to 0 results in this incorrect calculation.
Fix the initialization code to have it point to the end of the ring
instead. One way to think about this, is that we are setting the value
to be one prior to the first available descriptor.
Doing so, corrects the delta calculation in all cases. The original fix
only works if the first packet has exactly one descriptor. Otherwise, we
will report 1 less than the correct value.
As part of this fix, also update the MPASS assertions to match the real
expectations. First, ensure that prev is not equal to cur, since this
should never happen. Second, remove the assertion about prev==0 || delta
!= 0. It looks like that originated from when the em driver was
converted to iflib. It seems like it was supposed to ensure that delta
was non-zero. However, because we originally returned 0 delta for the
first calculation, the "prev == 0" was tacked on.
Instead, replace this with a check that delta is greater than zero,
after the correction necessary when the ring pointers wrap around.
This new solution should fix the same bug as r341156 did, but in a more
robust way.
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D18545
The first packet after the ring is initialized was never
completed as isc_txd_credits_update() would not include it in the
count of completed packets. This caused netmap to never complete
a batch. See PR 233022 for more details.
PR: 233022
Reported by: lev
Reviewed by: lev
MFC after: 3 days
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D17931
- Fix assert/panic on receive when Jumbo Frames are enabled.
From the commit I made to ixl:
"It turns out that *_isc_rxd_available is supposed to return how many
packets are available to be cleaned on the rx ring. This patch removes
a section of code where if the budget argument is 1, the function would return
one if there was a descriptor available, not necessarily a packet.
This is okay in regular mtu 1500 traffic since the max frame size is less
than the configured receive buffer size (2048), but this doesn't work when
received packets can span more than one descriptor, as is the case when the
mtu is 9000 and the receive buffer size is 4096."
- Fix possible Tx hang because *_isc_txd_credits_update returns incorrect result
From the commit by Krzysztof Galazka to ixl: "Function isc_txd_update_credits
called with clear set to false should return 1 if there are TX descriptors
already handled by HW. It was always returning 0 causing troubles with UDP TX
traffic."
PR: 231659
Reported by: lev@
Approved by: re (gjb@)
Sponsored by: Intel Corporation
These messages are totally redundant with the iflib messages.
They're also not very useful, since they don't include the
interface name.
Discussed with: shurd
Approved by: re (rgrimes)
Sponsored by: Dell EMC Isilon
When using a vlan with igb and the vlanhwcsum option, any mbufs which
already had the TCP, UDP, or SCTP checksum calculated and therefore don't
have the CSUM_[IP|IP6]_[TCP|UDP|SCTP] bits set in the csum_flags field would
have the L4 checksum corrupted by the hardware.
This was caused by the driver setting E1000_TXD_POPTS_TXSM any time a
checksum bit was set OR a vlan tag was present.
The patched driver only sets E1000_TXD_POPTS_TXSM when an offload is
requested.
PR: 231416
Reported by: pi
Approved by: re (gjb)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D17404
It seems igb supports TSO6, but the capability got lost in
the iflib update. Restore this capability.
PR: 231476
Reported by: lev
Reviewed by: erj
Approved by: re (gjb)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D17242
- Don't bother calling if_setbaudrate(9) as iflib_link_state_change(9)
takes care of that,
- correctly check for E1000_CTRL_EXT_LINK_MODE_GMII in E1000_CTRL_EXT [1],
- properly convert the uint16_t link_speed to a uint64_t baudrate by
using IF_Mbps() which contains an appropriate cast [2],
- remove the duplicate link down announcement when bootverbose isn't
zero and bring the remaining one in line with the other link state
messages.
o Remove a dead store to rid in em_if_msix_intr_assign(). [3]
o Or in the DMA coalescing Rx threshold so the other bits set in E1000_DMACR
remain intact as intended in igb_init_dmac(). [4]
Reported by: Coverity
CID: 1378464 [1], 1368765 [2], 1381681 [3], 1304929 [4]
- Ever since the workaround for the silicon bug of TSO4 causing MAC hangs
was committed in r295133, CSUM_TSO always got disabled unconditionally
by em(4) on the first invocation of em_init_locked(). However, even with
that problem fixed, it turned out that for at least e. g. 82579 not all
necessary TSO workarounds are in place, still causing MAC hangs even at
Gigabit speed. Thus, for stable/11, TSO usage was deliberately disabled
in r323292 (r323293 for stable/10) for the EM-class by default, allowing
users to turn it on if it happens to work with their particular EM MAC
in a Gigabit-only environment.
In head, the TSO workaround for speeds other than Gigabit was lost with
the conversion to iflib(9) in r311849 (possibly along with another one
or two TSO workarounds). Yet at the same time, for EM-class MACs TSO4
got enabled by default again, causing device hangs. Therefore, change the
default for this hardware class back to have TSO4 off, allowing users
to turn it on manually if it happens to work in their environment as
we do in stable/{10,11}. An alternative would be to add a whitelist of
EM-class devices where TSO4 actually is reliable with the workarounds in
place, but given that the advantage of TSO at Gigabit speed is rather
limited - especially with the overhead of these workarounds -, that's
really not worth it. [1]
This change includes the addition of an isc_capabilities to struct
if_softc_ctx so iflib(9) can also handle interface capabilities that
shouldn't be enabled by default which is used to handle the default-off
capabilities of e1000 as suggested by shurd@ and moving their handling
from em_setup_interface() to em_if_attach_pre() accordingly.
- Although 82543 support TSO4 in theory, the former lem(4) didn't have
support for TSO4, presumably because TSO4 is even more broken in the
LEM-class of MACs than the later EM ones. Still, TSO4 for LEM-class
devices was enabled as part of the conversion to iflib(9) in r311849,
causing device hangs. So revert back to the pre-r311849 behavior of
not supporting TSO4 for LEM-class at all, which includes not creating
a TSO DMA tag in iflib(9) for devices not having IFCAP_TSO4 set. [2]
- In fact, the FreeBSD TCP stack can handle a TSO size of IP_MAXPACKET
(65535) rather than FREEBSD_TSO_SIZE_MAX (65518). However, the TSO
DMA must have a maxsize of the maximum TSO size plus the size of a
VLAN header for software VLAN tagging. The iflib(9) converted em(4),
thus, first correctly sets scctx->isc_tx_tso_size_max to EM_TSO_SIZE
in em_if_attach_pre(), but later on overrides it with IP_MAXPACKET
in em_setup_interface() (apparently, left-over from pre-iflib(9)
times). So remove the later and correct iflib(9) to correctly cap
the maximum TSO size reported to the stack at IP_MAXPACKET. While at
it, let iflib(9) use if_sethwtsomax*().
This change includes the addition of isc_tso_max{seg,}size DMA engine
constraints for the TSO DMA tag to struct if_shared_ctx and letting
iflib_txsd_alloc() automatically adjust the maxsize of that tag in case
IFCAP_VLAN_MTU is supported as requested by shurd@.
- Move the if_setifheaderlen(9) call for adjusting the maximum Ethernet
header length from {ixgbe,ixl,ixlv,ixv,em}_setup_interface() to iflib(9)
so adjustment is automatically done in case IFCAP_VLAN_MTU is supported.
As a consequence, this adjustment now is also done in case of bnxt(4)
which missed it previously.
- Move the reduction of the maximum TSO segment count reported to the
stack by the number of m_pullup(9) calls (which in the worst case,
can add another mbuf and, thus, the requirement for another DMA
segment each) in the transmit path for performance reasons from
em_setup_interface() to iflib_txsd_alloc() as these pull-ups are now
done in iflib_parse_header() rather than in the no longer existing
em_xmit(). Moreover, this optimization applies to all drivers using
iflib(9) and not just em(4); all in-tree iflib(9) consumers still
have enough room to handle full size TSO packets. Also, reduce the
adjustment to the maximum number of m_pullup(9)'s now performed in
iflib_parse_header().
- Prior to the conversion of em(4)/igb(4)/lem(4) and ixl(4) to iflib(9)
in r311849 and r335338 respectively, these drivers didn't enable
IFCAP_VLAN_HWFILTER by default due to VLAN events not being passed
through by lagg(4). With iflib(9), IFCAP_VLAN_HWFILTER was turned on
by default but also lagg(4) was fixed in that regard in r203548. So
just remove the now redundant and defunct IFCAP_VLAN_HWFILTER handling
in {em,ixl,ixlv}_setup_interface().
- Nuke other redundant IFCAP_* setting in {em,ixl,ixlv}_setup_interface()
which is (more completely) already done in {em,ixl,ixlv}_if_attach_pre()
now.
- Remove some redundant/dead setting of scctx->isc_tx_csum_flags in
em_if_attach_pre().
- Remove some IFCAP_* duplicated either directly or indirectly (e. g.
via IFCAP_HWCSUM) in {EM,IGB,IXL}_CAPS.
- Don't bother to fiddle with IFCAP_HWSTATS in ixgbe(4)/ixgbev(4) as
iflib(9) adds that capability unconditionally.
- Remove some unused macros from em(4).
- Bump __FreeBSD_version as some of the above changes require the modules
of drivers using iflib(9) to be recompiled.
Okayed by: sbruno@ at 201806 DevSummit Transport Working Group [1]
Reviewed by: sbruno (earlier version), erj
PR: 219428 (part of; comment #10) [1], 220997 (part of; comment #3) [2]
Differential Revision: https://reviews.freebsd.org/D15720
I210 restore functionality if pxeboot rom is enabled on this device.
r333345 attempted to determine if this code was needed or it was some kind
of work around for a problem. Turns out, its definitely a work around for
hardware locking and synchronization that manifests itself if the option
Rom is enabled and is selected as a boot device (there was a PXE attempt).
Reviewed by: mmacy
Differential Revision: https://reviews.freebsd.org/D15439
r333345 added a panic to the default case statement on the incorrect
premise that it should "never happen" when in fact it is simply a
different adapter version.
Reported by: markj
Approved by: sbruno
With r333218 it is now possible for drivers to use an sx lock and thus sleep while
waiting on long running operations rather than DELAY().
Reported by: gallatin
Reviewed by: sbruno
Approved by: sbruno
MFC after: 1 month
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14984
"Under my tutelage Nicole did 85% of the work. At the time it seemed
simplest for a number of reasons to put my copyright on it. I now consider
that to have been a mistake."
Submitted by: Matthew Macy <mmacy@mattmacy.io>
Reviewed by: shurd
Approved by: shurd
Differential Revision: https://reviews.freebsd.org/D14766
The gcc 7 does check for switch statement fall through cases, and if legit,
such complaint can besilenced by /* FALLTHROUGH */ comment. Unfortunately
such comment is quite limited, but will still notify the reader.
This patch is backport from illumos, see
https://www.illumos.org/rb/r/941/
Reviewed by: eadler
Differential Revision: https://reviews.freebsd.org/D14663
Uses of mallocarray(9).
The use of mallocarray(9) has rocketed the required swap to build FreeBSD.
This is likely caused by the allocation size attributes which put extra pressure
on the compiler.
Given that most of these checks are superfluous we have to choose better
where to use mallocarray(9). We still have more uses of mallocarray(9) but
hopefully this is enough to bring swap usage to a reasonable level.
Reported by: wosch
PR: 225197
The value written to E1000_TARC(0) wasn't intended to have every bit but
E1000_TARC0_CB_MULTIQ_3_REQ cleared; a ~ was missing.
Also change the referenced spec update section in the comment to the correct
section.
Sponsored by: Intel Corporation
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
Email address has changed, uses consistent name (Matthew, not Matt)
Reported by: Matthew Macy <mmacy@mattmacy.io>
Differential Revision: https://reviews.freebsd.org/D13537
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Improved logging added in r323879 exposed an error during
attach. We need the irq, not the rid to work correctly. em uses
shared irqs, so it will use the same irq for TX as RX. bnxt does
not use shared irqs, or TX irqs at all, so there's no need to set
the TX irq affinity.
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12496
GPUs: radeonkms, i915kms
NICs: if_em, if_igb, if_bnxt
This metadata isn't used yet, but it will be handy to have later to
implement automatic module loading.
Reviewed by: imp, mmacy
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12488
If the packet is smaller than MTU, disable the TSO flags.
Move TCP header parsing inside the IS_TSO?() test.
Add a new IFLIB_NEED_ZERO_CSUM flag to indicate the checksums need to be zeroed before TX.
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12442
This was really too big of a commit even if everything worked, but there
are multiple new issues introduced in the one huge commit, so it's not
worth keeping this until it's fixed.
I'll work on splitting this up into logical chunks and introduce them one
at a time over the next week or two.
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
by Matt Macy as well as other changes which he has accepted via pull
request to his github repo at https://github.com/mattmacy/networking/
This should bring -CURRENT and the github repo into close enough sync to
allow small feature branches rather than a large chain of interdependant
patches being developed out of tree. The reset of the synchronization
should be able to be completed on github by splitting the remaining
changes that are not yet ready into short feature branches for later
review as smaller commits.
Here is a summary of changes included in this patch:
1) More checks when INVARIANTS are enabled for eariler problem
detection
2) Group Task Queue cleanups
- Fix use of duplicate shortdesc for gtaskqueue malloc type.
Some interfaces such as memguard(9) use the short description to
identify malloc types, so duplicates should be avoided.
3) Allow gtaskqueues to use ithreads in addition to taskqueues
- In some cases, this can improve performance
4) Better logging when taskqgroup_attach*() fails to set interrupt
affinity.
5) Do not start gtaskqueues until they're needed
6) Have mp_ring enqueue function enter the ABDICATED rather than BUSY
state. This moves the TX to the gtaskq and allows processing to
continue faster as well as make TX batching more likely.
7) Add an ift_txd_errata function to struct if_txrx. This allows
drivers to inspect/modify mbufs before transmission.
8) Add a new IFLIB_NEED_ZERO_CSUM for drivers to indicate they need
checksums zeroed for checksum offload to work. This avoids modifying
packet data in the TX path when possible.
9) Use ithreads for iflib I/O instead of taskqueues
10) Clean up ioctl and support async ioctl functions
11) Prefetch two cachlines from each mbuf instead of one up to 128B. We
often need to parse packet header info beyond 64B.
12) Fix potential memory corruption due to fence post error in
bit_nclear() usage.
13) Improved hang detection and handling
14) If the packet is smaller than MTU, disable the TSO flags.
This avoids extra packet parsing when not needed.
15) Move TCP header parsing inside the IS_TSO?() test.
This avoids extra packet parsing when not needed.
16) Pass chains of mbufs that are not consumed by lro to if_input()
rather call if_input() for each mbuf.
17) Re-arrange packet header loads to get as much work as possible done
before a cache stall.
18) Lock the context when calling IFDI_ATTACH_PRE()/IFDI_ATTACH_POST()/
IFDI_DETACH();
19) Attempt to distribute RX/TX tasks across cores more sensibly,
especially when RX and TX share an interrupt. RX will attempt to
take the first threads on a core, and TX will attempt to take
successive threads.
20) Allow iflib_softirq_alloc_generic() to request affinity to the same
cpus an interrupt has affinity with. This allows TX queues to
ensure they are serviced by the socket the device is on.
21) Add new iflib sysctls to net.iflib:
- timer_int - interval at which to run per-queue timers in ticks
- force_busdma
22) Add new per-device iflib sysctls to dev.X.Y.iflib
- rx_budget allows tuning the batch size on the RX path
- watchdog_events Count of watchdog events seen since load
23) Fix error where netmap_rxq_init() could get called before
IFDI_INIT()
24) e1000: Fixed version of r323008: post-cold sleep instead of DELAY
when waiting for firmware
- After interrupts are enabled, convert all waits to sleeps
- Eliminates e1000 software/firmware synchronization busy waits after
startup
25) e1000: Remove special case for budget=1 in em_txrx.c
- Premature optimization which may actually be incorrect with
multi-segment packets
26) e1000: Split out TX interrupt rather than share an interrupt for
RX and TX.
- Allows better performance by keeping RX and TX paths separate
27) e1000: Separate igb from em code where suitable
Much easier to understand separate functions and "if (is_igb)" than
previous tests like "if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC))"
#blamebruno
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12235
Do not use malloc(M_NOWAIT), wait is possible there, and the malloc
failures where not checked. Do not forget to free malloced memory.
Reported and tested by: pho
Approved by: sbruno
Sponsored by: The FreeBSD Foundation
Post-cold sleep instead of DELAY when waiting for firmware.
Convert softc mutex to an SX lock. Change all waits to sleeps
once interrupts are enabled (and it is safe to sleep).
Submitted by: Matt Macy <matt@mattmacy.io>
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12101
according to the enabled interface capability bits. Also remove
some dead code, which tried to preserve already set contents of
E1000_WUC while that register is completely overwritten shortly
after in all cases.
recieve descriptors for the igb(4) class of devices. This will
allow a better definition for maximum going forward. Some igb(4)
devices support more than the default 4K.
Reported by: Jason (j@nitrology.com)
Sponsored by: Limelight Networks
- restore newer code for vf, i350, i210, i211
- restore dmac init code for i354 and i350
- restore WUC/WUFC update
- check for igb mac type before attempting trying to assert
a media changed event.
- handle link events for igb(4) and em(4) devices differently
and appropriately for their respective model types.
Submitted by: Matt Macy <mmacy@mattmacy.io>
Sponsored by: Limelight Networks
Two blocks in e1000_ich8lan.c are misaligned, causing noise with some
compilers (gcc 6).
Reviewed by: imp, erj
Differential Revision: https://reviews.freebsd.org/D10741
so that we can use it in iflib to detect pause frames.
The igb(4) driver definitely used to use this in its old timer function and
I see no reason to restrict it to that driver only.
Sponsored by: Limelight Networks
