When an existing process is provided, the thread selected to use
to initialize the new thread could have exited and be reaped.
Acquire the proc lock earlier to ensure the thread remains valid.
Reviewed by: jhb, julian (previous version)
MFC after: 3 days
smlal, and umlal the output registers are allowed to be the same as either
input registers, where in ARMv4 and ARMv5 they could only be the same as the
last input register.
- It did not work with GENERIC kernel after r250603 because
options PROCDESC was required for pdfork(2). It now just uses fork(2)
instead when this syscall is not available.
- Fix verify(). This function was broken in r250602 because the outermost
"()" was removed from the condition !(isalnum() || ispunct()).
It prevented hostnames including "-", for example.
ensure that all such commands have a non-zero retry count except for those
that are expected to fail (for example, because they are used to probe for
feature support).
While it is possible to pass a retry count down to the hardware driver in
the command request structure, no hardware driver currently implements any
retry logic. The hardware doesn't know much about the context of a single
request, so it makes more sense to handle retries at a layer that does.
This adds retry loops to the mmc_wait_for_cmd() and mmc_wait_for_app_cmd()
functions. These functions are the gateway from other code within mmc.c
to the hardware. App commands are a sequence of two commands and a retry
has to rerun both of them in order, so it needs its own retry loop.
Retry looping is specifically NOT implemented in mmc_wait_for_request()
because it is the gateway for children on the bus, and they have to
implement their own retry logic depending on what makes sense for them.
address alignment of mappings.
- MAP_ALIGNED(n) requests a mapping aligned on a boundary of (1 << n).
Requests for n >= number of bits in a pointer or less than the size of
a page fail with EINVAL. This matches the API provided by NetBSD.
- MAP_ALIGNED_SUPER is a special case of MAP_ALIGNED. It can be used
to optimize the chances of using large pages. By default it will align
the mapping on a large page boundary (the system is free to choose any
large page size to align to that seems best for the mapping request).
However, if the object being mapped is already using large pages, then
it will align the virtual mapping to match the existing large pages in
the object instead.
- Internally, VMFS_ALIGNED_SPACE is now renamed to VMFS_SUPER_SPACE, and
VMFS_ALIGNED_SPACE(n) is repurposed for specifying a specific alignment.
MAP_ALIGNED(n) maps to using VMFS_ALIGNED_SPACE(n), while
MAP_ALIGNED_SUPER maps to VMFS_SUPER_SPACE.
- mmap() of a device object now uses VMFS_OPTIMAL_SPACE rather than
explicitly using VMFS_SUPER_SPACE. All device objects are forced to
use a specific color on creation, so VMFS_OPTIMAL_SPACE is effectively
equivalent.
Reviewed by: alc
MFC after: 1 month
has to be recalculated every time the SD clock frequency changes.
Also, tidy up the counter calculation... it makes no sense to calculate
a value one larger than the limit, then whine that it's too large and
truncate it to the limit. If the BROKEN_TIMEOUT quirk is set, don't
calculate the counter at all, just set it to the limit value.
We now pay attention to the maxio field in the XPT_PATH_INQ CCB,
and if it is set, propagate it up to physio via the si_iosize_max
field in the cdev structure.
We also now pay attention to the PIM_UNMAPPED capability bit in the
XPT_PATH_INQ CCB, and set the new SI_UNMAPPED cdev flag when the
underlying SIM supports unmapped I/O.
scsi_sa.c: Add unmapped I/O support and propagate the SIM's
maximum I/O size up.
Adjust scsi_tape_read_write() in the same way that
scsi_read_write() was changed to support unmapped
I/O. We overload the readop parameter with bits
that tell us whether it's an unmapped I/O, and we
need to set the CAM_DATA_BIO CCB flag. This change
should be backwards compatible in source and
binary forms.
MFC after: 1 week
Sponsored by: Spectra Logic
I removed functionality not proposed for POSIX in Austin group issue #411.
A man page (my own) and test cases will follow in later commits.
PR: 176233
Submitted by: Jukka Ukkonen
The previous method was to set the D_UNMAPPED_IO flag in the cdevsw
for the driver. The problem with this is that in many cases (e.g.
sa(4)) there may be some instances of the driver that can handle
unmapped I/O and some that can't. The isp(4) driver can handle
unmapped I/O, but the esp(4) driver currently cannot. The cdevsw
is shared among all driver instances.
So instead of setting a flag on the cdevsw, set a flag on the cdev.
This allows drivers to indicate support for unmapped I/O on a
per-instance basis.
sys/conf.h: Remove the D_UNMAPPED_IO cdevsw flag and replace it
with an SI_UNMAPPED cdev flag.
kern_physio.c: Look at the cdev SI_UNMAPPED flag to determine
whether or not a particular driver can handle
unmapped I/O.
geom_dev.c: Set the SI_UNMAPPED flag for all GEOM cdevs.
Since GEOM will create a temporary mapping when
needed, setting SI_UNMAPPED unconditionally will
work.
Remove the D_UNMAPPED_IO flag.
nvme_ns.c: Set the SI_UNMAPPED flag on cdevs created here
if NVME_UNMAPPED_BIO_SUPPORT is enabled.
vfs_aio.c: In aio_qphysio(), check the SI_UNMAPPED flag on a
cdev instead of the D_UNMAPPED_IO flag on the cdevsw.
sys/param.h: Bump __FreeBSD_version to 1000045 for the switch from
setting the D_UNMAPPED_IO flag in the cdevsw to setting
SI_UNMAPPED in the cdev.
Reviewed by: kib, jimharris
MFC after: 1 week
Sponsored by: Spectra Logic
the order that they arrive, to holding
(a) granted write lock requests, followed by
(b) granted read lock requests, followed by
(c) ungranted requests, in order of arrival.
This changes the stopping condition for iterating through granted locks to
see if a new request can be granted: When considering a read lock request,
we can stop iterating as soon as we see a read lock request, since anything
after that point is either a granted read lock request or a request which
has not yet been granted. (For write lock requests, we must still compare
against all granted lock requests.)
For workloads with R parallel reads and W parallel writes, this improves
the time spent from O((R+W)^2) to O(W*(R+W)); i.e., heavy parallel-read
workloads become significantly more scalable.
No statistically significant change in buildworld time has been measured,
but synthetic tests of parallel 'dd > /dev/null' and 'openssl enc >/dev/null'
with the input file cached yield dramatic (up to 10x) improvement with high
(up to 128 processes) levels of parallelism.
Reviewed by: kib
