r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
Modern GCC and Clang simply ignore the qualifier, while the old base GCC
produces a warning (treated as an error in the kernel build).
Approved by: cem
MFC after: 5 days
The new flag, -c <period>, sets the interrupt coalescing period in
microseconds through the new ioat(4) API ioat_set_interrupt_coalesce().
Also add a -z flag to zero ioat statistics before tests, to make it easy
to measure results.
Sponsored by: EMC / Isilon Storage Division
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
Allows DMA from/to arbitrary KVA or physical address. /dev/ioat_test
must be enabled by root and is only R/W root, so this is approximately
as dangerous as /dev/mem and /dev/kmem.
Sponsored by: EMC / Isilon Storage Division
The IOAT hardware supports writing a 64-bit pattern to some destination
buffer. The same limitations on buffer length apply as for copy
operations. Throughput is a bit higher (probably because fill does not
have to spend bandwidth reading from a source in memory).
Support for testing Block Fill has been added to ioatcontrol(8) and the
ioat_test device. ioatcontrol(8) accepts the '-f' flag, which tests
Block Fill. (If the flag is omitted, the tool tests copy by default.)
The '-V' flag, in conjunction with '-f', verifies that buffers are
filled in the expected pattern.
Tested on: Broadwell DE (Xeon D-1500)
Sponsored by: EMC / Isilon Storage Division
We only need to borrow a mutex for the drain sleep and the 0->1
transition, so just reuse an existing one for now.
The wchan is arbitrary. Using refcount itself would have required
__DEVOLATILE(), so use the lock's address instead.
Different uses are tagged by kind, although we only do anything with
that information in INVARIANTS builds.
Sponsored by: EMC / Isilon Storage Division
Replace custom Linux-like logging with a thin shim around
device_printf(), when the softc is available.
In ioat_test, shim around printf(9) instead.
Sponsored by: EMC / Isilon Storage Division
Don't run the selftest until after we've enabled bus mastering, or the
DMA engine can't copy anything for our test.
Create the ioat_test device on attach, if so tuned. Destroy the
ioat_test device on teardown.
Replace deprecated 'CALLOUT_MPSAFE' with correct '1' in callout_init().
Sponsored by: EMC / Isilon Storage Division
The test logic now preallocates memory before running the test.
The buffer size is now configurable. Post-copy verification is
configurable. The number of copies to chain into one transaction (one
interrupt) is configurable.
A 'duration' mode is added, which repeats the test until the duration
has elapsed, reporting the B/s and transactions completed.
ioatcontrol.8 has been updated to document the new arguments.
Initial limits (on this particular Broadwell-DE) (and when the
interrupts are working) seem to be: 256 interrupts/sec or ~6 GB/s,
whichever limit is more restrictive.
Unfortunately, it seems the interrupt-reset handling on Broadwell isn't
working as intended. That will be fixed in a later commit.
Sponsored by: EMC / Isilon Storage Division
I/OAT is also referred to as Crystal Beach DMA and is a Platform Storage
Extension (PSE) on some Intel server platforms.
This driver currently supports DMA descriptors only and is part of a
larger effort to upstream an interconnect between multiple systems using
the Non-Transparent Bridge (NTB) PSE.
For now, this driver is only built on AMD64 platforms. It may be ported
to work on i386 later, if that is desired. The hardware is exclusive to
x86.
Further documentation on ioat(4), including API documentation and usage,
can be found in the new manual page.
Bring in a test tool, ioatcontrol(8), in tools/tools/ioat. The test
tool is not hooked up to the build and is not intended for end users.
Submitted by: jimharris, Carl Delsey <carl.r.delsey@intel.com>
Reviewed by: jimharris (reviewed my changes)
Approved by: markj (mentor)
Relnotes: yes
Sponsored by: Intel
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D3456