With the patch applied the number of instruction events is 1% less and
number of mispredicted branch events is 5% less under multistream TCP
traffic load close to line rate.
Sponsored by: Solarflare Communications, Inc.
Approved by: gnn (mentor)
configured as 11b.
This came up when debugging other issues surrounding scanning and
channel modes.
What's going on:
* The VAP comes up as an 11b VAP, but on an 11n capable NIC;
* .. it announces HTINFO and MCS rates;
* The AP thinks it's an 11n capable device and transmits 11n frames
to the STA;
* But the STA is in 11b mode, and thus doesn't receive/ACK the frames.
It didn't happen for the ath(4) devices as the AR5416/AR9300 HALs
unconditionally enable MCS frame reception, even if the channel
mode is not 11n. But the Intel NICs are configured in 11b/11a/11g
modes when doing those, even if 11n is enabled and available.
So, don't announce 11n capabilities if the VAP isn't on an 11n
channel when sending management assocation request / reassociation
request frames.
TODO:
* Lots more testing - 11n should be "upgraded" after association,
and I just want to make sure I haven't broken 11n upgrade.
I shouldn't have - this is only happening for /sending/ association
requests, which APs aren't doing.
Tested:
* ath(4) APs (AR9331, AR7161+AR9280, AR934x)
* AR5416, STA mode
* Intel 5100, STA mode
PR: kern/196290
we need randomness in ULE. This removes random() call from the
rebalance interval code.
Submitted by: Harrison Grundy
Differential Revision: https://reviews.freebsd.org/D1968
milliseconds per transaction (DSM_MS_PER_TRANSACTION) calculation.
The comment was accurate many years ago when the kernel didn't
record I/O times on a per-I/O basis, but now that we do collect
that information in most areas, it isn't correct.
The milliseconds per transaction values are correct, assuming the
I/O duration has been recorded.
Sponsored by: Spectra Logic
MFC after: 3 days
On FreeBSD socklen_t is unsigned so the check negative len
in inet6_opt_append() is redundant and likely to be optimized
away by the compiler.
On other operating systems this is not necessarily so, and
in the future we may want to sign it so leave the check in
but place it in a secondary position as a subtle indication
that the bogus check is intentional.
Discussed with: rpaulo
CID: 1017783
Handling some interrupts in XLP (like PCIe and SATA) involves writing to
vendor specific registers as part of interrupt acknowledgement.
This was earlier done with xlp_establish_intr(), but a better solution
is to provide a function xlp_set_bus_ack() that can be used with
cpu_establish_hardintr(). This will allow platform initialization code to
setup these ACKs without changing the standrard drivers.
CDAI_FLAG_NONE advanced information CCB flag.
Support for the flag was merged to stable/10 in r279329, and the
__FreeBSD_version in stable/10 was bumped to 1001510.
Check for that version in the mps(4) and mpr(4) drivers when determining
whether to use the flag.
Sponsored by: Spectra Logic
MFC after: 3 days
r278854 introduced a race in the event channel handling code. We must make
sure that the pending bit is cleared before executing the filter, or else we
might miss other events that would be injected after the filter has ran but
before the pending bit is cleared.
While there also mask event channels while FreeBSD executes the ithread
bound to that event channel. This refrains Xen from injecting more
interrupts while the ithread has not finished it's work.
Sponsored by: Citrix Systems R&D
Reported by: sbruno, robak
Tested by: robak
block of free space after existing partition, take into account
provider's stripeoffset, since the result will be adjusted to this
value.
PR: 197989
MFC after: 1 week
level-triggered interrupt does not broadcast the EOI message to all
APICs in the system. Instead, interrupt handler must follow LAPIC EOI
with IOAPIC EOI. For modern IOAPICs, the later is done by writing to
EOIR register. Otherwise, Intel provided Linux with a trick of
temporary switching the pin config to edge and then back to level.
Detect presence of EOIR register by reading IO-APIC version. The
summary table in the comments was taken from the Linux kernel. For
Intel, newer IO-APICs are only briefly documented as part of the
ICH/PCH datasheet. According to the BKDG and chipset documentation,
AMD LAPICs do not provide EOI suppression, althought IO-APICs do
declare version 0x21 and implement EOIR.
The trick to temporary switch pin to edge mode to clear IRR was tested
on modern chipset, by pretending that EOIR is not present, i.e. by
forcing io_haseoi to zero.
Tunable hw.lapic_eoi_suppression disables the optimization.
Reviewed by: neel
Tested by: pho
Review: https://reviews.freebsd.org/D1943
Sponsored by: The FreeBSD Foundation
MFC after: 2 months
dereferencing. NULL is allowed by C11 and must be handled.
Reported and tested by: Vineela <vineela_17@yahoo.com>
PR: 198038
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Gather all the IRQ definitions to interrupt.h. Earlier these were in xlp.h
and pic.h. Update the definition of XLP_IRQ_IS_PICINTR to check for last
irq as well.
bfd_dwarf2_find_line() calls find_line() with NULL functionname_ptr,
which resulted in a crash on certain ELF objects.
This change was implemented independently from upstream binutils, but
I have checked that the crash does not happen there.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
This can occur when DW_AT_specification is used to refer to another DIE
that provides the actual DW_AT_name string. For example:
< 3><0x00000086> DW_TAG_subprogram
DW_AT_name PrettyStackTraceEntry
...
< 1><0x00002cf4> DW_TAG_subprogram
DW_AT_specification <0x00000086>
We will need to add support for DW_AT_specification, but in the interim
we should not segfault.
Obtained from: Elftoolchain (r3170)
Sponsored by: The FreeBSD Foundation
declares support for it. Newer versions of Xen works fine with x2APIC
code, but e.g. Xen 4.2 delivers GPF on the LAPIC MSR write, despite
x2APIC mode being known to hypervisor.
Discussed with: royger
Sponsored by: The FreeBSD Foundation
Errors from _thr_umutex_unlock2 should "never happen" in normal
circumstances. If they do, however, return them to the application
so it can fail early and loudly. Hiding the errors will only delay
the inevitable failure, making it harder to find and diagnose.
Submitted by: Eric van Gyzen <eric_van_gyzen@dell.com>
Obtained from: Dell Inc.
PR: 198914
MFC after: 1 week
to its previous, unowned state. This avoids compounding an existing
problem of inconsistent ownership.
Submitted by: Eric van Gyzen <eric_van_gyzen@dell.com>
Obtained from: Dell Inc.
PR: 198914
MFC after: 1 week
is empty, look up the umtx_pi and disown it if the current thread owns it.
This can happen if a signal or timeout removed the last waiter from
the queue, but there is still a thread in do_lock_pi() holding a reference
on the umtx_pi. The unlocking thread might not own the umtx_pi in this case,
but if it does, it must disown it to keep the ownership consistent between
the umtx_pi and the umutex.
Submitted by: Eric van Gyzen <eric_van_gyzen@dell.com>
with advice from: Elliott Rabe and Jim Muchow, also at Dell Inc.
Obtained from: Dell Inc.
PR: 198914
of packets. When the data payload length excluding any headers, of an
outgoing IPv4 packet exceeds PAGE_SIZE bytes, a special case in
ip_fragment() can kick in to optimise the outgoing payload(s). The
code which was added in r98849 as part of zero copy socket support
assumes that the beginning of any MTU sized payload is aligned to
where a MBUF's "m_data" pointer points. This is not always the case
and can sometimes cause large IPv4 packets, as part of ping replies,
to be split more than needed.
Instead of iterating the MBUFs to figure out how much data is in the
current chain, use the value already in the "m_pkthdr.len" field of
the first MBUF in the chain.
Reviewed by: ken @
Differential Revision: https://reviews.freebsd.org/D1893
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
any applications which need unpredictable random numbers, not merely those
which are cryptographic in nature.
If you work for a lottery and you're using random(3) to select the winning
numbers, please let me know.
