I've missed that network driver sometimes returns taken request back to
available queue without processing. Add new helper function for that case.
Reported by: flo
MFC after: 2 weeks
traps do appear in the regular call stack, rather than only in a special
trap frame, so we don't need to inject the trap-frame $pc into a returned
stack trace in DTrace.
MFC after: 3 days
Sponsored by: DARPA, AFRL
I/O interface.
Asynchronous operation, based on r280026 change, allows to not block virtual
CPU during I/O processing, that on slow/busy storage can take seconds.
Use of recently improved block I/O interface allows to process multiple
requests same time, that improves random I/O performance on wide storages.
Benchmarks of virtual disk, backed by ZVOL on RAID10 pool of 4 HDDs, show
~3.5 times random read performance improvements, while no degradation on
linear I/O. Guest CPU usage during test dropped from 100% to almost zero.
MFC after: 2 weeks
skip using the DTrace 'profile' provider on ARM. This causes stack traces
to skip various driver-and callout-related things as they do on x86, where
the likewise arbitrary values are '6' (32-bit) and '10' (64-bit) for
similar sorts of reasons.
MFC after: 3 days
Sponsored by: DARPA, AFRL
Original virtqueue design allows queued and out-of-order processing, but
helpers added in r253440 suppose only direct blocking in-order one.
It could be fine for network, etc., but it is a huge limitation for storage
devices.
standard way (including the nulterm byte in the data returned to userland).
This augments the existing sysctl_handle_string() in that this can be used
with const strings without ugly inappropriate casting.
On parallel random I/O this allows better utilize wide storage pools.
To not confuse prefetcher on linear I/O, consecutive requests are executed
sequentially, following the same logic as was earlier implemented in CTL.
Benchmarks of virtual AHCI disk, backed by ZVOL on RAID10 pool of 4 HDDs,
show ~3.5 times random read performance improvements, while no degradation
on linear I/O.
MFC after: 2 weeks
If zvol_geom_start is called with a BIO_DELETE from a thread which can
sleep it queues it for later processing by the zvol_geom_worker. The
zvol_geom_worker didn't have a delete case so would simply loose the bio
hence preventing the original caller from every completing. In addition
an other unknown types would suffer the same fate.
Allow zvol_geom_worker to process BIO_DELETE's via zvol_strategy and
return unsupported for all unknown bio types.
MFC after: 2 weeks
Sponsored by: Multiplay
strings returned to userland include the nulterm byte.
Some uses of sbuf_new_for_sysctl() write binary data rather than strings;
clear the SBUF_INCLUDENUL flag after calling sbuf_new_for_sysctl() in
those cases. (Note that the sbuf code still automatically adds a nulterm
byte in sbuf_finish(), but since it's not included in the length it won't
get copied to userland along with the binary data.)
Remove explicit adding of a nulterm byte in a couple places now that it
gets done automatically by the sbuf drain code.
PR: 195668
The SBUF_INCLUDENUL flag causes the nulterm byte at the end of the string
to be counted in the length of the data. If copying the data using the
sbuf_data() and sbuf_len() functions, or if writing it automatically with
a drain function, the net effect is that the nulterm byte is copied along
with the rest of the data.
The restore utility already knows the full-resolution timestamps, so the
only thing to do is to stop converting the timespecs to timevals and use
futimens() and utimensat().
Differential Revision: https://reviews.freebsd.org/D2020
Reviewed by: jhb
