Previous code supported only "continuous" code without any kind of
branch instructions. To change that, new function was implemented
which parses current instruction and returns an addres where
the jump might happen (alternative addr).
mdthread structure was extended to support two breakpoints
(one directly below current instruction and the second placed
at the alternative location).
One of them must trigger regardless the instruction has or has not been
executed due to condition field.
Upon cleanup, both software breakpoints are removed.
This implementation parses only the most common instructions
that are present in the code (like 99.99% of all), but there
is a chance there are some left, not covered by the parsing routine.
Parsing is done only for 32-bit instruction, no Thumb nor Thumb-2
support is provided.
Reviewed by: kib
Submitted by: Wojciech Macek <wma@semihalf.com>
Obtained from: Semihalf
Sponsored by: Juniper Networks Inc.
Differential Revision: https://reviews.freebsd.org/D4021
I discovered that we're logging each trap, which gets pretty spendy;
and there wasn't any further information on the pid/tid/progname involved.
I originally noticed this because I don't attach anything to /dev/log and so
the log() output stays going to the kernel. That's an oops on my part, but
I'm glad I did it.
This commit adds the following:
* a rate limiter, which could do with some eyeballs/ideas on how to
make it more predictable on SMP;
* log pid, tid, progname (comm) as part of the output.
I now get output like this:
Unaligned Load Word: pid=621 (pmcstat), tid=100060, pc=0xffffffff803ae898, badvaddr=0x40a10055
Unaligned Load Word: pid=621 (pmcstat), tid=100060, pc=0xffffffff803ae898, badvaddr=0x40a10051
Unaligned Load Word: pid=621 (pmcstat), tid=100060, pc=0xffffffff803ae898, badvaddr=0x40a1004d
Unaligned Load Word: pid=602 (login), tid=100042, pc=0xffffffff803ae898, badvaddr=0x401159
Unaligned Load Word: pid=602 (login), tid=100042, pc=0xffffffff803ae898, badvaddr=0x401155
Unaligned Load Word: pid=602 (login), tid=100042, pc=0xffffffff803ae898, badvaddr=0x401151
.. which makes it much easier to start figuring out what/where to fix.
The pc looks suss (it looks like it's in kernel space); I'll dig into that one next.
Tested:
* AR9331 SoC (Carambola2)
Certain invalid operations trigger hardware error conditions. Error
conditions that only halt one channel can be detected and recovered by
resetting the channel. Error conditions that halt the whole device are
generally not recoverable.
Add a sysctl to inject channel-fatal HW errors,
'dev.ioat.<N>.force_hw_error=1'.
When a halt due to a channel error is detected, ioat(4) blocks new
operations from being queued on the channel, completes any outstanding
operations with an error status, and resets the channel before allowing
new operations to be queued again.
Update ioat.4 to document error recovery; document blockfill introduced
in r290021 while we are here; document ioat_put_dmaengine() added in
r289907; document DMA_NO_WAIT added in r289982.
Sponsored by: EMC / Isilon Storage Division
whether an error is recoverable. Always re-dirty the buffer on errors
from write requests. The invalidation we used to do for errors not EIO
doesn't need to be done for a device that's really gone, since that's
done in a different path.
Reviewed by: mckusick@, kib@
mips24k/mips74k document that we need an explicit SYNC so to order
things correctly, even with access to uncachable memory.
We were doing calls to SYNC in the cache ops (inv, wbinv) but we
weren't doing it for uncachable memory.
When I ported this code from netbsd I was .. slightly mips74k greener.
I used writethrough because (a) it's what netbsd did, and (b) if I used
writethrough then things "didn't work."
Fast-forward a couple years, more MIPS hacking and a whole lot more
understanding of the bus APIs (the last few commits notwithstanding;
it's been a long week, ok?) and I have this working for arge,
argemdio, spi and ath. Hans has it working for USB. The ath barrier
code will come in a later commit.
This gets the routing throughput up from 220mbit -> 337mbit.
I'm sure the bridging throughput will be similarly improved.
Tested:
* QCA955x SoC, routing workload.
* use barriers in a slightly better fashion. You can blame this
glass of whiskey on putting barriers in the wrong spot. Grr adrian.
* steal/rewrite the mdio busy check from ag7100 from openwrt and
refactor the existing code out. This is .. more correct.
This seems to fix the boot-to-boot variation that I've been seeing
and it quietens the switch port status flapping.
Tested:
* QCA9558 SoC (AP135.)
Obtained from: Linux OpenWRT
This driver and the linux ag71xx driver both treat the transmit ring
as a circular linked list of descriptors. There's no "end" pointer
that is ever NULL - instead, it expects the MAC to hit a finished
descriptor (ARGE_DESC_EMPTY) and stop.
Now, since it's a circular buffer, we may end up with the hardware
hitting the beginning of our multi-descriptor frame before we've finished
setting it up. It then DMA's it in, starts sending it, and we finish
writing out the new descriptor. The hardware may then write its
completion for the next descriptor out; then we do, and when we next
read it it'll show up as "not done" and transmit completion stops.
This unfortunately manifests itself as the transmit queue always
being active and a massive TX interrupt storm. We need to actively
ACK packets back from the transmit engine and if we don't (eg because
we think the transmit isn't finished but it is) then the unit will
just keep generating interrupts.
I hit this finally with the below testing setup. This fixed it for me.
Strictly speaking I should put in a sync in between writing out all of
the descriptors and writing out that final descriptor.
Tested:
* QCA9558 SoC (AP135 reference board) w/ arge1 + vlans acting as a
router, and iperf -d (tcp, bidirectional traffic.)
Obtained from: Linux OpenWRT (ag71xx_main.c.)
The MIPS busdma sync operations currently are a big no-op on coherent memory.
This isn't strictly correct behaviour as we need a SYNC in here to ensure that
the writes have finished and are visible in main memory before the MMIO accesses
occur. This will have to be addressed in a later commit.
But, before that happens, let's at least do a flush here to make things
more "correct".
This is required for even remotely sensible behaviour on mips74k with
write-through memory enabled.
The mips74k programmers guide notes that reads can be re-ordered, even
uncached ones, so we need an explicit SYNC between them.
Yes, this is a case of a driver author actively doing a bus barrier
operation.
This ends up being necessary when the mips74k core is run in write-back
mode rather than write-through mode. That's coming in an upcoming
commit.
Tested:
* mips74k, QCA9558 SoC (AP135 reference board), arge<->arge interface
routing traffic tests.
send frames.
This matches the other check for space.
"enough" is a misnomer, for "reasons". The biggest reason is that
the TX ring is actually a circular linked list, with no head/tail pointers.
This is just a bit more headroom between head/tail so we have time to
schedule frames before we hit where the hardware is at.
Ideally this would be tunable and a little larger.
This flushes out the write to the system before anything continues.
The mips74k guide, chapter 3.3.3 (write gathering) notes that writes
can be buffered in FIFOs - even uncached ones - so we can't guarantee
the device has felt its effects. Now, since we're all lazy driver
authors and don't pepper read/write barriers everywhere, fake it here.
tested:
* mips74k - QCA9558 SoC (AP135 reference board)
self-documented, and eases addition of new ops.
For the similar reasons, eliminate UMTX_OP_MAX. nitems() handles the
only use of the symbol.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Fixes race condition observed under following circumstances:
1) I/O split on 128KB boundary with Intel NVMe controller.
Current Intel controllers produce better latency when
I/Os do not span a 128KB boundary - even if the I/O size
itself is less than 128KB.
2) Per-CPU I/O queues are enabled.
3) Child I/Os are submitted on different submission queues.
4) Interrupts for child I/O completions occur almost
simultaneously.
5) ithread for child I/O A increments bio_inbed, then
immediately is preempted (rendezvous IPI, higher priority
interrupt).
6) ithread for child I/O B increments bio_inbed, then completes
parent bio since all children are now completed.
7) parent bio is freed, and immediately reallocated for a VFS
or gpart bio (including setting bio_children to 1 and
clearing bio_driver1).
8) ithread for child I/O A resumes processing. bio_children
for what it thinks is the parent bio is set to 1, so it
thinks it needs to complete the parent bio.
Result is either calling a NULL callback function, or double freeing
the bio to its uma zone.
PR: 203746
Reported by: Drew Gallatin <gallatin@netflix.com>,
Marc Goroff <mgoroff@quorum.net>
Tested by: Drew Gallatin <gallatin@netflix.com>
MFC after: 3 days
Sponsored by: Intel
if they are not required for mounting rootfs. However, it's possible
that some setups try to mount them in mountcritlocal (ie from fstab).
Export the list of current root mount holds using a new sysctl,
vfs.root_mount_hold, and make mountcritlocal retry if "mount -a" fails
and the list is not empty.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3709
status registers for every interrupt. Check a common host channel
status interrupt register first, then conditionally read the
individual host channel status registers.
Submitted by: Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after: 1 week
b_asize can be zero if the block is compressed into an empty block
(ZIO_COMPRESS_EMPTY) and the trim code asserts that meaningless
zero-sized trimming is not attempted.
The logic for calling trim_map_free() is extracted into a new function
l2arc_trim() to minimize code duplication.
PR: 203473
Reported by: Willem Jan Withagen <wjw@digiware.nl>
Tested by: Willem Jan Withagen <wjw@digiware.nl>
MFC after: 11 days
We can't use copyout because destination memory is userland address
in another process but we have reference to respective page so map
the page into kernel address space and copy fragments there
receives video memory address from VideoCore through property mailbox
channel. Older versions of firmware (and the one that is currently part
of sysutils/u-boot-rpi and sysutils/u-boot-rpi2) returned real physical
address, newer one returns VideoCore bus address, so we need to convert
it to actual physical address. this version works with both older and
newer interface.
point, e.g. on RaspberryPi 2 when control is passed from loader to kernel
it contains garbage. So we use cpsr as a base for new cpsr value: if we
have reached this point it means current value is OK
Reviewed by: andrew
When using route-to (or reply-to) pf sends the packet directly to the output
interface. If that interface doesn't support checksum offloading the checksum
has to be calculated in software.
That was already done in the IPv4 case, but not for the IPv6 case. As a result
we'd emit packets with pseudo-header checksums (i.e. incorrect checksums).
This issue was exposed by the changes in r289316 when pf stopped performing full
checksum calculations for all packets.
Submitted by: Luoqi Chen
MFC after: 1 week
