The page daemon periodically invokes uma_reclaim() to reclaim cached
items from each zone when the system is under memory pressure. This
is important since the size of these caches is unbounded by default.
However it also results in bursts of high latency when allocating from
heavily used zones as threads miss in the per-CPU caches and must
access the keg in order to allocate new items.
With r340405 we maintain an estimate of each zone's usage of its
(per-NUMA domain) cache of full buckets. Start making use of this
estimate to avoid reclaiming the entire cache when under memory
pressure. In particular, introduce TRIM, DRAIN and DRAIN_CPU
verbs for uma_reclaim() and uma_zone_reclaim(). When trimming, only
items in excess of the estimate are reclaimed. Draining a zone
reclaims all of the cached full buckets (the previous behaviour of
uma_reclaim()), and may further drain the per-CPU caches in extreme
cases.
Now, when under memory pressure, the page daemon will trim zones
rather than draining them. As a result, heavily used zones do not incur
bursts of bucket cache misses following reclamation, but large, unused
caches will be reclaimed as before.
Reviewed by: jeff
Tested by: pho (an earlier version)
MFC after: 2 months
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16667
To permit larger values of MAXMEMDOM, which is currently 8 on amd64,
cpuset_setdomain(2) accepts a mask of size 256. In the kernel, domain
set masks are 64 bits wide, but can only represent a set of MAXMEMDOM
domains due to the use of the ds_order table.
Domain sets passed to cpuset_setdomain(2) are restricted to a subset
of their parent set, which is typically the root set, but before this
happens we modify the input set to exclude empty domains.
domainset_empty_vm() and other code which manipulates domain sets
expect the mask to be a subset of all_domains, so enforce that when
performing validation of cpuset_setdomain(2) parameters.
Reported and tested by: pho
Reviewed by: kib
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21477
This unbreaks using the powerpc64 loader on a 32-bit processor.
Approved by: jhibbits (mentor)
Differential Revision: https://reviews.freebsd.org/D21297
lldb prepends the thread name to log entries, and the existing thread
name for the FreeBSD ProcessMonitor thread was longer than the kernel's
supported thread name length, and so was truncated. This made logs hard
to read, as the truncated thread name ran into the log message. Shorten
"lldb.process.freebsd.operation" to just "freebsd.op" so that logs are
more readable.
(Upstreaming to lldb still to be done).
gets is unsafe and shouldn't be used (for many years now). Leave it in
the existing symbol version so anything that previously linked aginst it
still runs, but do not allow new software to link against it.
(The compatability/legacy implementation must not be static so that
the symbol and in particular the compat sym gets@FBSD_1.0 make it
into libc.)
PR: 222796 (exp-run)
Reported by: Paul Vixie
Reviewed by: allanjude, cy, eadler, gnn, jhb, kib, ngie (some earlier)
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D12298
The code used blindly ref based on an unsafely red address and then would
backpedal if necessary. This was safe in terms of memory access since
mounts are type-stable, but made for a potential a bug where the mount
was reused and had the count reset to 0 before this code decreased it.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21411
This fixes problem with parameters indicating a zero length or partial
parameters after an unknown parameter indicating to stop processing. It
also fixes a problem with state cookie parameters after unknown
parametes indicating to stop porcessing.
Thanks to Mark Wodrich from Google for finding two of these issues
by fuzz testing the userland stack and reporting them in
https://github.com/sctplab/usrsctp/issues/355
and
https://github.com/sctplab/usrsctp/issues/352
MFC after: 3 days
Similarly to the other routine stop taking the interlock for the lower
vnode. The interlock for nullfs vnode is still taken to ensure
stability of ->v_data.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21480
Future changes to posixshm will start tracking writeable mappings in order
to support file sealing. Tracking writeable mappings for an OBJT_DEFAULT
object is complicated as it may be swapped out and converted to an
OBJT_SWAP. One may generically add this tracking for vm_object, but this is
difficult to do without increasing memory footprint of vm_object and blowing
up memory usage by a significant amount.
On the other hand, the swap pager can be expanded to track writeable
mappings without increasing vm_object size. This change is currently in
D21456. Switch over to OBJT_SWAP in advance of the other changes to the
swap pager and posixshm.
o from FDT;
o from EFI;
o from Linux Boot API (ATAG).
U-Boot may pass RAM info all that 3 ways simultaneously.
We do select between FDT and EFI, but not for ATAG.
So this is not problem fix, but correctness check.
MFC after: 2 weeks
This unskips:
- lib.libc.stdlib.strtod_test.strtod_round
- lib.msun.fe_round_test.t_nofe_round
In lib/msun/tests/Makefile only define on fe_round_test.c because
lib.msun.ilogb_test.ilogb will get wrong results and needs more examination.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
data chunks. Abort the association if there are data chunks with larger
fragement sequence numbers than the fragement sequence of the last
fragment.
Thanks to Mark Wodrich from Google who found this issue by fuzz testing
the userland stack and reporting this issue in
https://github.com/sctplab/usrsctp/issues/355
MFC after: 3 days
When a vlan interface is created, its if_output is set directly to the
parent interface's if_output. This is fine in the normal case but has an
unfortunate consequence if you end up with a certain combination of vlan
and lagg interfaces.
Consider you have a lagg interface with a single laggport member. When
an interface is added to a lagg its if_output is set to
lagg_port_output, which blackholes traffic from the normal networking
stack but not certain frames from BPF (pseudo_AF_HDRCMPLT). If you now
create a vlan with the laggport member (not the lagg interface) as its
parent, its if_output is set to lagg_port_output as well. While this is
confusing conceptually and likely represents a misconfigured system, it
is not itself a problem. The problem arises when you then remove the
lagg interface. Doing this resets the if_output of the laggport member
back to its original state, but the vlan's if_output is left pointing to
lagg_port_output. This gives rise to the possibility that the system
will panic when e.g. bpf is used to send any frames on the vlan
interface.
Fix this by creating a new function, vlan_output, which simply wraps the
parent's current if_output. That way when the parent's if_output is
restored there is no stale usage of lagg_port_output.
Reviewed by: rstone
Differential Revision: D21209
- Fix warnings from igor and mandoc.
- Provide a brief description of the separation between zones and their
backend slab allocators.
- Document cache zones and secondary zones.
- Document the kernel config options added in r350659.
- Document the uma_zalloc_pcpu() and uma_zfree_pcpu() wrappers.
- Document uma_zone_reserve(), uma_zone_reserve_kva() and
uma_zone_prealloc().
- Document uma_zone_alloc() and uma_zone_freef().
- Add some missing MLINKs and Xrefs.
MFC after: 2 weeks
The returned error number may be EINTR or ERESTART depending on
whether or not the signal is supposed to interrupt the system call.
Reported and tested by: pho
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
The bhyve virtual local APIC uses an instance-global flag to indicate
when an error LVT is being delivered to prevent infinite recursion.
Use a function argument instead to reduce the amount of instance-global
state.
This was inspired by reviewing the bhyve save/restore work, which
saves a copy of the instance-global state for each vlapic.
Smart OS bug: https://smartos.org/bugview/OS-7777
Submitted by: Patrick Mooney
Reviewed by: markj, rgrimes
Obtained from: SmartOS / Joyent
Differential Revision: https://reviews.freebsd.org/D20365
When the pwm.9 manual was removed, a symlink between pwmbus.9 and pwm.9 was
created, but there's an entry in ObsoleteFiles.inc to remove pwn.9, meaning
that on every installation pwm.9 is created, and make delete-old deletes it.
Remove the entry from ObsoleteFiles.inc, the symlink is clearly intentional
and shouldn't be removed.
Reviewed by: imp, ian
Approved by: imp (implicit, review OK)
Differential Revision: https://reviews.freebsd.org/D21198
XPT_DEV_ADVINFO call should be protected by the lock of the specific
device it is addressed to, not the lock of SES device. In some weird
case, probably with hardware violating standards, it sometimes caused
NULL dereference due to race.
To protect from it further, add lock assertion to *_dev_advinfo().
MFC after: 1 week
Sponsored by: iXsystems, Inc.
