in UVM, excluding uvmexp.free, which needs special treatment and will be
done with a separate commit. Cuts system time for a build by 20-25% on
a 48 CPU machine w/DIAGNOSTIC.
- Avoid 64-bit integer divide on every fault (for rnd_add_uint32).
rbtree page lookup was introduced during the NetBSD 5.0 development cycle to
bypass lock contention problems with the (then) global page hash, and was a
temporary solution to allow us to make progress. radixtree is the intended
replacement.
Ok yamt@.
lock for use of the pagedaemon policy code. Discussed on tech-kern.
PR kern/54209: NetBSD 8 large memory performance extremely low
PR kern/54210: NetBSD-8 processes presumably not exiting
PR kern/54727: writing a large file causes unreasonable system behaviour
pserialize_perform() is now basically just xc_barrier(XC_HIGHPRI).
No more tentacles throughout the scheduler. Simplify the psz read
count for diagnostic assertions by putting it unconditionally into
cpu_info.
From rmind@, tidied up by me.
- Delete the per-entry lock, and borrow the associated vnode's v_interlock
instead. We need to acquire it during lookup anyway. We can revisit this
in the future but for now it's a stepping stone, and works within the
quite limited context of what we have (BSD namecache/lookup design).
- Implement an idea that Mateusz Guzik (mjg@FreeBSD.org) gave me. In
cache_reclaim(), we don't need to lock out all of the CPUs to garbage
collect entries. All we need to do is observe their locks unheld at least
once: then we know they are not in the critical section, and no longer
have visibility of the entries about to be garbage collected.
- The above makes it safe for sysctl to take only namecache_lock to get stats,
and we can remove all the crap dealing with per-CPU locks.
- For lockstat, make namecache_lock a static now we have __cacheline_aligned.
- Avoid false sharing - don't write back to nc_hittime unless it has changed.
Put a a comment in place explaining this. Pretty sure this was there in
2008/2009 but someone removed it (understandably, the code looks weird).
- Use a mutex to protect the garbage collection queue instead of atomics, and
adjust the low water mark up so that cache_reclaim() isn't doing so much
work at once.
- Adapt to cpu_need_resched() changes. Avoid lost & duplicate IPIs and ASTs.
sched_resched_cpu() and sched_resched_lwp() contain the logic for this.
- Changes for LSIDL to make the locking scheme match the intended design.
- Reduce lock contention and false sharing further.
- Numerous small bugfixes, including some corrections for SCHED_FIFO/RT.
- Use setrunnable() in more places, and merge cut & pasted code.
Remove const from the 2nd argument.
const char ** and char ** are incompatible types and it was a cost to keep
the technically incompatible form for a more purist variation. NetBSD was
almost the last alive OS to still keep the const argument (known leftovers:
Minix and Illumos).
Keep the const form for the internal purposes inside citrus and rump.
Address the build breakage fallout in the same change.
There are no ABI changes.
Change accepted by core@.
GCC_NO_FORMAT_TRUNCATION -Wno-format-truncation (GCC 7/8)
GCC_NO_STRINGOP_TRUNCATION -Wno-stringop-truncation (GCC 8)
GCC_NO_STRINGOP_OVERFLOW -Wno-stringop-overflow (GCC 8)
GCC_NO_CAST_FUNCTION_TYPE -Wno-cast-function-type (GCC 8)
use these to turn off warnings for most GCC-8 complaints. many
of these are false positives, most of the real bugs are already
commited, or are yet to come.
we plan to introduce versions of (some?) of these that use the
"-Wno-error=" form, which still displays the warnings but does
not make it an error, and all of the above will be re-considered
as either being "fix me" (warning still displayed) or "warning
is wrong."
CVS: ----------------------------------------------------------------------
CVS: CVSROOT cvs.NetBSD.org:/cvsroot
CVS: please use "PR category/123" to have the commitmsg appended to PR 123
CVS:
CVS: Please evaluate your changes and consider the following.
CVS: Abort checkin if you answer no.
CVS: => For all changes:
CVS: Do the changed files compile?
CVS: Has the change been tested?
CVS: => If you are not completely familiar with the changed components:
CVS: Has the change been posted for review?
CVS: Have you allowed enough time for feedback?
CVS: => If the change is major:
CVS: => If the change adds files to, or removes files from $DESTDIR:
CVS: => If you are changing a library or kernel interface:
CVS: Have you successfully run "./build.sh release"?
CVS: ----------------------------------------------------------------------
CVS: CVSROOT cvs.NetBSD.org:/cvsroot
CVS: please use "PR category/123" to have the commitmsg appended to PR 123
CVS:
CVS: Please evaluate your changes and consider the following.
CVS: Abort checkin if you answer no.
CVS: => For all changes:
CVS: Do the changed files compile?
CVS: Has the change been tested?
CVS: => If you are not completely familiar with the changed components:
CVS: Has the change been posted for review?
CVS: Have you allowed enough time for feedback?
CVS: => If the change is major:
CVS: => If the change adds files to, or removes files from $DESTDIR:
CVS: => If you are changing a library or kernel interface:
CVS: Have you successfully run "./build.sh release"?
Benefits:
- larger seeds -- a 128-bit key alone is not enough for `128-bit security'
- better resistance to timing side channels than AES
- a better-understood security story (https://eprint.iacr.org/2018/349)
- no loss in compliance with US government standards that nobody ever
got fired for choosing, at least in the US-dominated western world
- no dirty endianness tricks
- self-tests
Drawbacks:
- performance hit: throughput is reduced to about 1/3 in naive measurements
=> possible to mitigate by using hardware SHA-256 instructions
=> all you really need is 32 bytes to seed a userland PRNG anyway
=> if we just used ChaCha this would go away...
XXX pullup-7
XXX pullup-8
XXX pullup-9
- Add support for dynamic NETMAP algorithm (stateful net-to-net).
- Add most of the support for the dynamic NAT rules; a little bit more
userland work is needed to finish this up and enable.
- Replace 'stateful-ends' with more permissive 'stateful-all'.
- Add various tunable parameters and document them, see npf-params(7).
- Reduce the memory usage of the connection state table (conndb).
- Portmap rewrite: use memory more efficiently, handle addresses dynamically.
- Bug fix: add splsoftnet()/splx() around the thmap writers and comment.
- npftest: clean up and simplify; fix some memleaks to make ASAN happy.
