When debugging a deadlock, it is useful to follow the full chain of locks as
far as possible.
Reviewed by: jhb
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12115
Rather than repeatedly nesting loops, separate concerns with a single loop
per call stack level. Use a table to drive the recursive routine. Handle
missing topology layers more gracefully (infer a single unit).
Analyze some additional optional layers which may be present on e.g. AMD Zen
systems (groups, aka dies, per package; and cachegroups, aka CCXes, per
group).
Display that additional information in the boot-time topology information,
when it is relevent (non-one).
Reviewed by: markj@, mjoras@ (earlier version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12019
This mode allows other clean buffers to arrive while we flush the buf
lists for the vnode, which is fine for the targeted use. We only need
that all buffers existed at the time of the function start were
flushed. In fact, only one assert has to be relaxed.
In collaboration with: pho
Reviewed by: rmacklem
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
X-Differential revision: https://reviews.freebsd.org/D12083
Right now we only need to pad when writing kernel dump headers, so
flatten three related subroutines into one. The encrypted kernel dump
code already writes out its key in a dumper.blocksize-sized block.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11647
This helps simplify the code in kern_shutdown.c and reduces the number
of globally visible functions.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11603
dump_start() and dump_finish() are responsible for writing kernel dump
headers, optionally writing the key when encryption is enabled, and
initializing the initial offset into the dump device.
Also remove the unused dump_pad(), and make some functions static now that
they're only called from kern_shutdown.c.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11584
sbuf is filled to capacity by vsnprintf(), the loop exits without error, and
the sbuf is not marked as auto-extendable.
SBUF_HASROOM() evaluates true if there is room for one or more non-NULL
characters, but in the case that the sbuf was filled exactly to capacity,
SBUF_HASROOM() evaluates false. Consequently, sbuf_vprintf() incorrectly
assigns an ENOMEM error to the sbuf when in fact everything is fine, in turn
poisoning the buffer for all subsequent operations.
Correct by moving the ENOMEM assignment into the loop where it can be made
unambiguously.
As a related safety net change, explicitly check for the zero bytes drained
case in sbuf_drain() and set EDEADLK as the error. This avoids an infinite loop
in sbuf_vprintf() if a drain function were to inadvertently return a value of
zero to sbuf_drain().
Reviewed by: cem, jtl, gallatin
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D8535
during drain operations. When an sbuf is configured to use this feature by way
of the SBUF_DRAINTOEOR sbuf_new() flag, top-level sections started with
sbuf_start_section() create a record boundary marker that is used to avoid
flushing partial records.
Reviewed by: cem,imp,wblock
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D8536
it automatically after it runs.
The config_intrhook mechanism allows a driver to stall the boot process
until device(s) required for booting are available, by not allowing system
inits to proceed until all intrhook functions have been unregistered.
Virtually all existing code simply unregisters from within the hook function
when it gets called.
This new function makes that common usage more convenient. Instead of
allocating and filling in a struct, passing it to a function that might (in
theory) fail, and checking the return code, now a driver can simply call
this cannot-fail routine, passing just the intrhook function and its arg.
Differential Revision: https://reviews.freebsd.org/D11963
another parameter that identifies a starting point in the memory address
block. Radix is a power of two, blk is a multiple of radix, and the
starting point is in the range [blk, blk+radix), so that blk can always be
computed from the other two. This change drops the blk parameter from the
meta functions and computes it instead. (On amd64, for example, this
change reduces subr_blist.o's text size by 7%.)
It also makes the radix parameters unsigned to address concerns that the
calculation of '-radix' might overflow without the -fwrapv option. (See
https://reviews.freebsd.org/D11819.)
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11964
cpumask it probably means we are unable to sent interrupts to CPUs outside
the map. As such only return the current CPU when it's within the mask
otherwise return the first valid CPU.
This is needed on ThunderX as, in a dual socket configuration, we are
unable to send MSI/MSI-X interrupts between sockets.
Reviewed by: mmel
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D11957
vm_page_grab() on consecutive page indices. Besides simplifying the code
in the caller, vm_page_grab_pages() allows for batching optimizations.
For example, the current implementation replaces calls to vm_page_lookup()
on consecutive page indices by cheaper calls to vm_page_next().
Reviewed by: kib, markj
Tested by: pho (an earlier version)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D11926
p1003_1b.aio_listio_max is now a tunable. Its value is reflected in the
sysctl of the same name, and the sysconf(3) variable _SC_AIO_LISTIO_MAX.
Its value will be bounded from below by the compile-time constant
AIO_LISTIO_MAX and from above by the compile-time constant
MAX_AIO_QUEUE_PER_PROC and the tunable vfs.aio.max_aio_queue.
Reviewed by: jhb, kib
MFC after: 3 weeks
Relnotes: yes
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D11601
o Replace __riscv64 with (__riscv && __riscv_xlen == 64)
This is required to support new GCC 7.1 compiler.
This is compatible with current GCC 6.1 compiler.
RISC-V is extensible ISA and the idea here is to have built-in define
per each extension, so together with __riscv we will have some subset
of these as well (depending on -march string passed to compiler):
__riscv_compressed
__riscv_atomic
__riscv_mul
__riscv_div
__riscv_muldiv
__riscv_fdiv
__riscv_fsqrt
__riscv_float_abi_soft
__riscv_float_abi_single
__riscv_float_abi_double
__riscv_cmodel_medlow
__riscv_cmodel_medany
__riscv_cmodel_pic
__riscv_xlen
Reviewed by: ngie
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D11901
When all instances of a lock type are destroyed (for example, after a
module unload), the corresponding witness entry remains associated with
that lock type. In this case, we shouldn't panic if a new instance of the
lock type is created and its lock class does not match that recorded in the
witness entry.
Reviewed by: jhb
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11788
'skip', which denote, respectively, the largest number of blocks that can be
managed by a subtree of that height, and one less than the number of nodes
in a subtree of that height. This change removes the 'skip' argument from
those functions because 'skip' can be trivially computed from 'radius'.
This change also redefines 'skip' so that it denotes the number of nodes in
the subtree, and so changes loop upper bound tests from '<= skip' to '<
skip' to account for the change.
The 'skip' field is also removed from the blist struct.
The self-test program is changed so that the print command includes the
cursor value in the output.
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
Linux specific things to the native fdescfs file system.
Unlike FreeBSD, the Linux fdescfs is a directory containing a symbolic
links to the actual files, which the process has open.
A readlink(2) call on this file returns a full path in case of regular file
or a string in a special format (type:[inode], anon_inode:<file-type>, etc..).
As well as in a FreeBSD, opening the file in the Linux fdescfs directory is
equivalent to duplicating the corresponding file descriptor.
Here we have mutually exclusive requirements:
- in case of readlink(2) call fdescfs lookup() method should return VLNK
vnode otherwise our kern_readlink() fail with EINVAL error;
- in the other calls fdescfs lookup() method should return non VLNK vnode.
For what new vnode v_flag VV_READLINK was added, which is set if fdescfs has beed
mounted with linrdlnk option an modified kern_readlinkat() to properly handle it.
For now For Linux ABI compatibility mount fdescfs volume with linrdlnk option:
mount -t fdescfs -o linrdlnk null /compat/linux/dev/fd
Reviewed by: kib@
MFC after: 1 week
Relnotes: yes
Atomic updates to v_wire_count are a significant source of contention, so
combine multiple updates into one in this easy case. Also remove an old
printf that gets executed if the page is shared-busied, which is a case
that will lead to a panic anyway.
Reviewed by: alc, kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11791
request that their clock_settime() methods be called at a given offset
from top-of-second. This adds a timeout_task to the rtc_instance so that
each clock can be separately added to taskqueue_thread with the scheduling
it prefers, instead of looping through all the clocks at once with a
single task on taskqueue_thread. If a driver doesn't call clock_schedule()
the default is the old behavior: clock_settime() is queued immediately.
The motivation behind this is that I was on the path of adding identical
code to a third RTC driver to figure out a delta to top-of-second and
sleep for that amount of time because writing the the RTC registers resets
the hardware's concept of top-of-second. (Sometimes it's not top-of-second,
some RTC clocks tick over a half second after you set their time registers.)
Worst-case would be to sleep for almost a full second, which is a rude thing
to do on a shared task queue thread.
over the scheduling precision than 'ticks' can offer, and because sometimes
you're already working with sbintime_t units and it's dumb to convert them
to ticks just so they can get converted back to sbintime_t under the hood.
No functional change.
This is handy for FreeBSD derivatives that want to modify the value of
MAXPATHLEN, but not the kld_file_stat ABI.
Submitted by: Siddhant Agarwal <sagarwal AT isilon.com>
Sponsored by: Dell EMC Isilon
New kern.lognosys values are
1 - log to ctty
2 - log to console
3 - log to both.
Inspired by: eugen
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
"leaf" functions for alloc, free, and fill. After the change, the interface
functions call "meta" unconditionally, and the "meta" functions recur
unconditionally in looping over their descendants. The "meta" functions
start with a validity test, and then a test for the "leaf" case, before
falling into the general recursive case. This simplifies and shrinks the
code, and, for "free" and "fill" moves panic tests that check the same meta
node repeatedly in a loop to a place that will have each node tested once.
Remove irrelevant null checks from blist_free and blist_fill.
Make the code that initializes a meta node the same in blist_meta_alloc and
blist_meta_fill.
Parenthesize return expressions in blst_meta_fill.
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
Most realtime clocks store the year as 2 BCD digits. Some add a century bit
to extend the range another hundred years. Every clock driver has its own
code to determine the century and pass a full year value to clock_ct_to_ts().
Now clock drivers can just convert BCD to bin and store the result in the
clocktime struct and let the common code figure out the century. Clocks
with a century bit can just add 100 to year if the century bit is on.
of-line whitespace, remove excessive whitespace and blank lines, remove
dead code, follow our standard style for function definitions, and
correct grammatical and factual errors in some of the comments.
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
that start in 1970, assume most conversions are going to be for recent dates
and use a precomputed number of days through the end of 2016.
This is a do-over of r320997, hopefully this time with 100% more workiness.
The first attempt had an off-by-one error, but instead of just adding
another mysterious +1 adjustment, this rearranges the relationship between
recent_base_year and recent_base_days so that the latter is the number of
days that occurred before the start of the associated year (instead of the
count thru the end of that year). This makes the recent_base stuff work
more like the original loop logic that didn't need any +1 adjustments.
This appears to have been an oversight in r213536.
Reviewed by: markj
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D11521
the IO type (Admin or NVM) using XPT op-codes XPT_NVME_ADMIN or
XPT_NVME_IO.
Submitted by: Chuck Tuffli <chuck@tuffli.net>
Differential Revision: https://reviews.freebsd.org/D10247
Using the https://github.com/google/capsicum-test/ suite, the
PosixMqueue.CapModeForked test was failing due to an ECAPMODE after
calling kmq_notify(). On further inspection, the dynamically
loaded syscall entry was initialized with sy_flags zeroed out, since
SYSCALL_INIT_HELPER() left sysent.sy_flags with the default value.
Add a new helper SYSCALL{,32}_INIT_HELPER_F() which takes an
additional argument to specify the sy_flags value.
Submitted by: Siva Mahadevan <smahadevan@freebsdfoundation.org>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D11576
Make the %b formatter accept number formatting flags. It will now accept
alternate form, precision, and length modifiers. It also now partially
supports field width (but forces left justification).
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11284
on clock drivers.
This tracks multiple concurrent realtime clock drivers in a list sorted by
clock resolution. When system time changes (and periodically) the
clock_settime() methods of all registered clocks are invoked.
To initialize system time, each driver is tried in turn from best to worst
resolution, until one succesfully returns a valid time.
The code no longer holds a mutex while calling the clock_settime() and
clock_gettime() methods of the registered clocks. This allows clock drivers
to do whatever kind of locking or sleeping is necessary (this is especially
important for i2c clock chips since i2c drivers often need to sleep).
A new clock_register_flags() function allows the clock driver to pass
flags. The flags currently defined help support drivers that use their own
techniques to avoid roundoff errors (prevents the 4/5 rounding done by the
subr_rtc code). A driver which may need to wait for resources (such as bus
ownership) may pass a flag to indicate that it will obtain system time for
itself after waiting for resources; this is merely an optimization to avoid
the common code retrieving a timespec that will never get used.
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D11484
Uiomove can only block when the segflag is UIO_USERSPACE,
otherwise we end up just doing a bcopy (or nothing) and
moving cursors. So only emit witness warnings and
set deadlock thread flags in the UIO_USERSPACE case.
Reviewed by: kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D11489