Commit Graph

259714 Commits

Author SHA1 Message Date
br
64cb3b9636 Provide a template for busdma code for RISC-V.
RISC-V ISA specifies no cache management instructions so leave cache
operations in cpufunc.h as no-op for now.

Note some new hardware comes with their own memory-mapped cache
management controller.

Tested on HiFive Unleashed board with cgem(4).

Reviewed by:	markj
Obtained from:	arm64
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D20126
2019-05-07 13:41:43 +00:00
emaste
4b1a9bdef5 Use @generated tag in generated files
Multiple tools use @generated to identify generated files (for example,
in a review Phabricator will by default hide diffs in generated files).
Use the @generated tag in makeobjops.awk and vnode_if.awk as we've done
for other generated files.

Sponsored by:	The FreeBSD Foundation
2019-05-07 13:04:26 +00:00
tsoome
b9bb0a1f15 command_bcache() does not use argv
Therefore mark argv __unused.
2019-05-07 10:01:45 +00:00
marius
02751cbaa9 o Avoid determining the MAC class (LEM/EM or IGB) - possibly even multiple
times - on every interrupt by using an own set of device methods for the
  IGB class. This translates to introducing igb_if_intr_{disable,enable}()
  and igb_if_{rx,tx}_queue_intr_enable() with that IGB-specific code moved
  out of their EM counterparts and otherwise continuing to use the EM IFDI
  methods also for IGB.
  Note that igb_if_intr_{disable,enable}() also issue E1000_WRITE_FLUSH as
  lost with the conversion of igb(4) to iflib(4).
  Also note, that the em_if_{disable,enable}_intr() methods are renamed to
  em_if_intr_{disable,enable}() for consistency with the names used in the
  interface declaration.
o In em_intr():
  - Don't bother to bail out if the interrupt type is "legacy", i. e. INTx
    or MSI, as iflib(4) doesn't use ift_legacy_intr methods for MSI-X. All
    other iflib(4)-based drivers avoid this check, too.
  - Given that only the MSI-X interrupts have one-shot behavior (by taking
    advantage of the EIAC register), explicitly disable interrupts. Hence,
    em_intr() now matches what {em,igb}_irq_fast() previously did (in case
    of igb(4) supposedly also to work around MSI message reordering errata
    on certain systems).
o In em_if_intr_disable():
  - Clear the EIAC register unconditionally for 82574 and not just in case
    of MSI-X, matching em_if_intr_enable() and bringing back the last hunk
    of r206437 lost with the iflib(4) conversion.
  - Write to EM_EIAC for clearing said register instead of to the IGB-only
    E1000_EIAC used ever since the iflib(4) conversion.

Reviewed by:	shurd
Differential Revision:	https://reviews.freebsd.org/D20176
2019-05-07 08:31:54 +00:00
marius
50c146a61b o Use iflib_fast_intr_rxtx() also for "legacy" interrupts, i. e. INTx and
MSI. Unlike as with iflib_fast_intr_ctx(), the former will also enqueue
  _task_fn_tx() in addition to _task_fn_rx() if appropriate, bringing TCP
  TX throughput of EM-class devices on par with the MSI-X case and, thus,
  close to wirespeed/pre-iflib(4) times again. [1]
  Note that independently of the interrupt type, the UDP performance with
  these MACs still is abysmal and nowhere near to where it was before the
  conversion of em(4) to iflib(4).
o In iflib_init_locked(), announce which free list failed to set up.
o In _task_fn_tx() when running netmap(4), issue ifdi_intr_enable instead
  of the ifdi_tx_queue_intr_enable method in case of a "legacy" interrupt
  as the latter is valid with MSI-X only.
o Instead of adding the missing - and apparently convoluted enough that a
  DBG_COUNTER_INC was put into a wrong spot in _task_fn_rx() - checks for
  ifdi_{r,t}x_queue_intr_enable being available in the MSI-X case also to
  iflib_fast_intr_rxtx(), factor these out to iflib_device_register() and
  make the checks fail gracefully rather than panic. This avoids invoking
  the checks at runtime over and over again in iflib_fast_intr_rxtx() and
  _task_fn_{r,t}x() - even if it's just in case of INVARIANTS - and makes
  these functions more readable.
o In iflib_rx_structures_setup(), only initialize LRO resources if device
  and driver have LRO capability in order to not waste memory. Also, free
  the LRO resources again if setting them up fails for one of the queues.
  However, don't bother invoking iflib_rx_sds_free() in that case because
  iflib_rx_structures_setup() doesn't call iflib_rxsd_alloc() either (and
  iflib_{device,pseudo}_register() will issue iflib_rx_sds_free() in case
  of failure via iflib_rx_structures_free(), but there definitely is some
  asymmetry left to be fixed, though).
o Similarly, free LRO resources again in iflib_rx_structures_free().
o In iflib_irq_set_affinity(), handle get_core_offset() errors gracefully
  instead of panicing (but only in case of INVARIANTS). This is a follow-
  up to r344132, as such driver bugs shouldn't be fatal.
o Likewise, handle unknown iflib_intr_type_t in iflib_irq_alloc_generic()
  gracefully, too.
o Bring yet more sanity to iflib_msix_init():
  - If the device doesn't provide enough MSI-X vectors or not all vectors
    can be allocate so the expected number of queues in addition to admin
    interrupts can't be supported, try MSI next (and then INTx) as proper
    MSI-X vector distribution can't be assured in such cases. In essence,
    this change brings r254008 forward to iflib(4). Also, this is the fix
    alluded to in the commit message of r343934.
  - If the MSI-X allocation has failed, don't prematurely announce MSI is
    going to be used as the latter in fact may not be available either.
  - When falling back to MSI, only release the MSI-X table resource again
    if it was allocated in iflib_msix_init(), i. e. isn't supplied by the
    driver, in the first place.
o In mp_ndesc_handler(), handle unknown type arguments gracefully, too.

PR:		235031 (likely) [1]
Reviewed by:	shurd
Differential Revision:	https://reviews.freebsd.org/D20175
2019-05-07 08:28:35 +00:00
tsoome
8d47118c9e loader: bcache code does not need to check argument for free() 2019-05-07 08:14:30 +00:00
tsoome
9236c6f0b8 loader: use safer DPRINTF body for non-debug case 2019-05-07 07:46:40 +00:00
dchagin
ff74a853f5 Remove wrong copyright line. Discussed with Carlos Neira.
Reported by:	Rodney W. Grimes
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D13656
2019-05-07 05:08:13 +00:00
kib
dcee73e7cf amd64: fix BUS_SPACE_MAXSIZE to 64bit max value.
Reviewed by:	jhb, tychon (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D20154
2019-05-07 01:18:57 +00:00
dougm
7da63e7938 The intention of the blist cursor is for the search for free blocks to
resume where the last search left off. Suppose that there are no free
blocks of size 32, but plenty of size 16. If we repeatedly request
size 32 blocks, fail, and retry with size 16 blocks, then the failures
all reset the cursor to the beginning of memory, making the 16 block
allocation use a first fit, rather than next fit, strategy.

This change has blist_alloc make a copy of the cursor for its own
decision making, and only updates the real blist cursor after a
successful allocation, making those 16 block searches behave like
next-fit searches.

Approved by: markj (mentor)
Differential Revision: https://reviews.freebsd.org/D20177
2019-05-06 22:12:15 +00:00
marius
a45957355f - Remove the unused ifc_link_irq and ifc_mtx_name members of struct iflib_ctx.
- Remove the only ever written to ift_db_mtx_name member of struct iflib_txq.
- Remove the unused or only ever written to ifr_size, ifr_cq_pidx, ifr_cq_gen
  and ifr_lro_enabled members of struct iflib_rxq.
- Consistently spell DMA, RX and TX uppercase in comments, messages etc.
  instead of mixing with some lowercase variants.
- Consistently use if_t instead of a mix of if_t and struct ifnet pointers.
- Bring the function comments of _iflib_fl_refill(), iflib_rx_sds_free() and
  iflib_fl_setup() in line with reality.
- Judging problem reports, people are wondering what on earth messages like:
  "TX(0) desc avail = 1024, pidx = 0"
  are trying to indicate. Thus, extend this string to be more like that of
  non-iflib(4) Ethernet MAC drivers, notifying about a watchdog timeout due
  to which the interface will be reset.
- Take advantage of the M_HAS_VLANTAG macro.
- Use false/true rather than FALSE/TRUE for variables of type bool.
- Use FALLTHROUGH as advocated by style(9).
2019-05-06 20:56:41 +00:00
phil
42e8bd2979 Import libxo-1.0.4:
- Avoid NULL deref in xo_xml_leader_len (replacing local fix in rS345967)
- update copyright dates
- update test cases
- fix uncommitted version change

Submitted by:	phil
MFC after:	2 weeks
2019-05-06 20:20:21 +00:00
dchagin
2c9faf1048 Adds sys/class/net devices to linsysfs.
Only two interfaces are created eth0 and lo and they expose
the following properties:
address, addr_len, flags, ifindex, mty, tx_queue_len and type.

Initial patch developed by Carlos Neira in 2017 and finished by me.

PR:		223722
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D13656
2019-05-06 20:01:13 +00:00
dchagin
b83adbe591 Rewrite linux_ifflags() in more readable Linuxulator style.
Reviewed by:	emaste
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D20146
2019-05-06 19:57:51 +00:00
dchagin
df8d6fbda3 Complete r347052 (https://reviews.freebsd.org/D20137) as it it was not
a final revision.

Fix style issues and change bool-like variables from int to bool.

Reviewed by:	emaste
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D20141
2019-05-06 19:56:13 +00:00
imp
eacbda1040 Simplify boot1 allocation of handles.
There's no need to pre-malloc the number of handles. Instead call
LocateHandles twice, once to get the size, and once to get the
data.
2019-05-06 19:35:30 +00:00
mav
c8679b8bb2 Drop periph lock around cam_periph_unmapmem().
Since r345656 it may call copyout(), that may sleep.

MFC after:	3 days
Sponsored by:	iXsystems, Inc.
2019-05-06 19:08:03 +00:00
dchagin
775c2bf391 The build process generates assym.inc from genassym.o, so don't forget
to clean genassym.o

MFC after:	2 weeks
2019-05-06 18:46:42 +00:00
imp
f7192df893 Abstract out efi_devpath_to_handle to search for a handle that matches
the desired devpath.
2019-05-06 18:39:27 +00:00
imp
44c35a8446 We only ever need one devinfo per handle. So allocate it outside of
looping over the filesystem modules rather than doing a malloc + free
each time through the loop. In addition, nothing changes from loop to
loop, so setup the new devinfo outside the loop as well.
2019-05-06 18:39:22 +00:00
imp
7131ecd11a Reach over and pull in devpath.c from libefi
This allows us to remove three nearly identical functions because the
differences don't matter, and the size difference is trivial.
2019-05-06 18:38:46 +00:00
cem
6058a49bde List-ify kernel dump device configuration
Allow users to specify multiple dump configurations in a prioritized list.
This enables fallback to secondary device(s) if primary dump fails.  E.g.,
one might configure a preference for netdump, but fallback to disk dump as a
second choice if netdump is unavailable.

This change does not list-ify netdump configuration, which is tracked
separately from ordinary disk dumps internally; only one netdump
configuration can be made at a time, for now.  It also does not implement
IPv6 netdump.

savecore(8) is already capable of scanning and iterating multiple devices
from /etc/fstab or passed on the command line.

This change doesn't update the rc or loader variables 'dumpdev' in any way;
it can still be set to configure a single dump device, and rc.d/savecore
still uses it as a single device.  Only dumpon(8) is updated to be able to
configure the more complicated configurations for now.

As part of revving the ABI, unify netdump and disk dump configuration ioctl
/ structure, and leave room for ipv6 netdump as a future possibility.
Backwards-compatibility ioctls are added to smooth ABI transition,
especially for developers who may not keep kernel and userspace perfectly
synced.

Reviewed by:	markj, scottl (earlier version)
Relnotes:	maybe
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D19996
2019-05-06 18:24:07 +00:00
hselasky
97403087df Use PCIV_INVALID in pci_channel_offline() in the LinuxKPI.
Build tested drm-current-kmod prior to commit.

MFC after:		1 week
Submitted by:		slavash@
Sponsored by:		Mellanox Technologies
2019-05-06 16:22:45 +00:00
hselasky
6e5bade211 Disabling a PCI device should only disable busmaster in the LinuxKPI.
As Linux comment for this function point:
Signal to the system that the PCI device is not in use by the system
anymore. This only involves disabling PCI bus-mastering, if active.

Build tested drm-current-kmod prior to commit.

MFC after:		1 week
Submitted by:		slavash@
Sponsored by:		Mellanox Technologies
2019-05-06 16:17:38 +00:00
hselasky
ec09430682 Implement print_hex_dump_debug() function macro in the LinuxKPI.
Build tested drm-current-kmod prior to commit.

MFC after:		1 week
Submitted by:		slavash@
Sponsored by:		Mellanox Technologies
2019-05-06 16:10:26 +00:00
emaste
ef0f4aa09f Reformat arm64 linux syscalls.master per current style
Equivalent to r339958 for sys/kern/syscalls.master.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D14858
2019-05-06 16:07:14 +00:00
hselasky
f4b58c1701 Allow controlling pr_debug at runtime in the LinuxKPI.
Turning on pr_debug at compile time make it non-optional at runtime.
This often means that the amount of the debugging is unbearable.
Allow developer to turn on pr_debug output only when needed.

Build tested drm-current-kmod prior to commit.

MFC after:		1 week
Submitted by:		kib@
Sponsored by:		Mellanox Technologies
2019-05-06 16:00:20 +00:00
royger
35bdc8c699 geom: fix initialization order
There's a race between the initialization of devsoftc.mtx (by devinit)
and the creation of the geom worker thread g_run_events, which calls
devctl_queue_data_f. Both of those are initialized at SI_SUB_DRIVERS
and SI_ORDER_FIRST, which means the geom worked thread can be created
before the mutex has been initialized, leading to the panic below:

 wpanic: mtx_lock() of spin mutex (null) @ /usr/home/osstest/build.135317.build-amd64-freebsd/freebsd/sys/kern/subr_bus.c:620
 cpuid = 3
 time = 1
 KDB: stack backtrace:
 db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe003b968710
 vpanic() at vpanic+0x19d/frame 0xfffffe003b968760
 panic() at panic+0x43/frame 0xfffffe003b9687c0
 __mtx_lock_flags() at __mtx_lock_flags+0x145/frame 0xfffffe003b968810
 devctl_queue_data_f() at devctl_queue_data_f+0x6a/frame 0xfffffe003b968840
 g_dev_taste() at g_dev_taste+0x463/frame 0xfffffe003b968a00
 g_load_class() at g_load_class+0x1bc/frame 0xfffffe003b968a30
 g_run_events() at g_run_events+0x197/frame 0xfffffe003b968a70
 fork_exit() at fork_exit+0x84/frame 0xfffffe003b968ab0
 fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe003b968ab0
 --- trap 0, rip = 0, rsp = 0, rbp = 0 ---
 KDB: enter: panic
 [ thread pid 13 tid 100029 ]
 Stopped at      kdb_enter+0x3b: movq    $0,kdb_why

Fix this by initializing geom at SI_ORDER_SECOND instead of
SI_ORDER_FIRST.

Sponsored by:		Citrix Systems R&D
Reviewed by:		kevans, markj
Differential revision:	https://reviews.freebsd.org/D20148
2019-05-06 09:48:34 +00:00
kib
9e9048e3c2 Do not flush NFS node from NFS VOP_SET_TEXT().
The more appropriate place to do the flushing is VOP_OPEN().  This was
uncovered because VOP_SET_TEXT() is now called with the vnode'
vm_object rlocked, which is incompatible with the flush operations.

After the move, there is no need for NFS-specific VOP_SET_TEXT
overload.

Sponsored by:	The FreeBSD Foundation
MFC after:	30 days
2019-05-06 08:49:43 +00:00
kib
9d98ef7bc1 Noted by: alc
Reviewed by:	alc, markj (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	6 days
2019-05-06 08:46:11 +00:00
ae
f60e7d9600 Add ipsec.ko to required_modules for rc.d/ipsec script.
Thus it can be automatically loaded if ipsec_enable="YES" and option IPSEC
is not in the kernel config.

MFC after:	1 week
2019-05-06 08:30:53 +00:00
tychon
49786fb7ad zero inputs to vm_page_initfake() for predictable results
Reviewed by:	kib
Submitted by:	Anton Rang <rang at acm.org>
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D20162
2019-05-06 00:57:05 +00:00
jhibbits
09419c83ec powerpc/booke: Use #ifdef __powerpc64__ instead of hw_direct_map in places
Since the DMAP is only available on powerpc64, and is *always* available on
Book-E powerpc64, don't penalize either side (32-bit or 64-bit) by always
checking hw_direct_map to perform operations.  This saves 5-10% time on
various ports builds, and on buildworld+buildkernel on Book-E hardware.

MFC after:	3 weeks
2019-05-05 20:23:43 +00:00
jhibbits
76a7416922 powerpc/booke: Fix size check for phys_avail in pmap bootstrap
Use the nitems() macro instead of the expansion, a'la r298352.  Also, fix the
location of this check to after initializing availmem_regions_sz, so that the
check isn't always against 0, thus always failing (nitems(phys_avail) is always
more than 0).
2019-05-05 20:05:50 +00:00
mav
afd259f1d6 Decode some more ATA commands found in ACS-4.
MFC after:	1 week
2019-05-05 17:10:12 +00:00
markj
e346003b41 Ensure that error is initialized in ufs_bmap_seekdata().
Reported and tested by:	jhibbits
MFC with:	r346932
Sponsored by:	The FreeBSD Foundation
2019-05-05 16:57:03 +00:00
mav
6b175066b3 Decode Deallocate Logical Block Features.
MFC after:	1 week
2019-05-05 15:47:21 +00:00
kib
2dc0d9edaa Switch to use shared vnode locks for text files during image activation.
kern_execve() locks text vnode exclusive to be able to set and clear
VV_TEXT flag. VV_TEXT is mutually exclusive with the v_writecount > 0
condition.

The change removes VV_TEXT, replacing it with the condition
v_writecount <= -1, and puts v_writecount under the vnode interlock.
Each text reference decrements v_writecount.  To clear the text
reference when the segment is unmapped, it is recorded in the
vm_map_entry backed by the text file as MAP_ENTRY_VN_TEXT flag, and
v_writecount is incremented on the map entry removal

The operations like VOP_ADD_WRITECOUNT() and VOP_SET_TEXT() check that
v_writecount does not contradict the desired change.  vn_writecheck()
is now racy and its use was eliminated everywhere except access.
Atomic check for writeability and increment of v_writecount is
performed by the VOP.  vn_truncate() now increments v_writecount
around VOP_SETATTR() call, lack of which is arguably a bug on its own.

nullfs bypasses v_writecount to the lower vnode always, so nullfs
vnode has its own v_writecount correct, and lower vnode gets all
references, since object->handle is always lower vnode.

On the text vnode' vm object dealloc, the v_writecount value is reset
to zero, and deadfs vop_unset_text short-circuit the operation.
Reclamation of lowervp always reclaims all nullfs vnodes referencing
lowervp first, so no stray references are left.

Reviewed by:	markj, trasz
Tested by:	mjg, pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
Differential revision:	https://reviews.freebsd.org/D19923
2019-05-05 11:20:43 +00:00
kib
ce1a272ee3 Do not collapse objects with OBJ_NOSPLIT backing swap object.
NOSPLIT swap objects are not anonymous, they are used by tmpfs regular
files and POSIX shared memory.  For such objects, collapse is not
permitted.

Reported by:	mjg
Reviewed by:	markj, trasz
Tested by:	mjg, pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D19923
2019-05-05 11:06:19 +00:00
kib
e3b87f7a32 imgact_elf: do not relock the text vnode if possible.
We unlock the vnode around malloc(M_WAITOK), to make it possible for
pagedaemon to flush vnode pages for us.  Instead of doing it
unconditionally, first try M_NOWAIT allocation, which typically
succeed.  Only on failure, unlock the vnode and retry with M_WAITOK.

Reviewed by:	markj, trasz
Tested by:	mjg, pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D19923
2019-05-05 11:04:01 +00:00
cs
0d62ce2428 Colemak Mod DH keyboard layout
This is a minor modification of the Colemak keyboard layout.
See: http://colemakmods.github.io/mod-dh/

Reviewed by:	philip
Differential Revision:	https://reviews.freebsd.org/D20133
2019-05-05 09:02:32 +00:00
tsoome
38b668d19f loader: validate sectorsize argument in disk_open()
The bug and patch is reported against 11.2, but it is good idea to have
the check in place for all versions.

PR:		236585
Submitted by:	john@feith.com
Reported by:	john@feith.com
MFC after:	1 day
2019-05-05 06:38:47 +00:00
adrian
cae80982c1 [ath_rate_sample] Have the final attempted rate in 11n modes to be the lowest one.
Right now ath_rate_sample has a fixed rate schedule, rather than the minstrel_ht
style "best, good, most reliable" triplet.  So, if higher rates are tried then
it'll not fail back to a lower MCS rate in that transmission schedule.

This means that in low SNR situations it'll not easily drop to MCS0 unless enough
transmissions occur to allow rate control to eventually decide to drop; and if
it's TCP traffic it'll get slowed down because of packet loss.

It's worse for 2-stream and 3-stream rates; it doesn't ever fall back to lower
stream rates, and these higher stream rates required higher SNR to work.

So instead let's (for now?) have each of the 11n transmit rates use MCS0 as
the last attempt. ath_rate_sample will quickly see that rate succeeds more
and will move to it much quicker.

Testing:

* AR9344 (Wasp) - 2G STA mode
2019-05-05 06:32:40 +00:00
adrian
c8d5298b87 [ath] [ath_rate] Fix ANI calibration during non-ACTIVE states; start poking at rate control
These are some fun issues I've found with my upstairs wifi link at such a ridiculous
low signal level (like, < 5dB.)

* Add per-station tx/rx rssi statistics, in potential preparation to use that
  in the RX rate control.

* Call the rate control on each received frame to let it potentially use
  it as a hint for what rates to potentially use.  It's a no-op right now.

* Do ANI calibration during scan as well. The ath_newstate() call was disabling the
  ANI timer and only re-enabling it during transitions to _RUN.  This has the
  unfortunate side-effect that if ANI deafened the NIC because of interference
  and it disassociated, it wouldn't be reset and the scan would never hear beacons.

The ANI configuration is stored at least globally on some HALs and per-channel
on others.  Because of this a NIC reset wouldn't help; the ANI parameters would
simply be programmed back in.

Now, I have a feeling I also need to do this during AUTH/ASSOC too and maybe,
if I'm feeling clever, I need to reset the ANI parameters on a given channel
during a transition through INIT or if the VAP is destroyed/re-created.
However for now this gets me out of the immediate weeds with connectivity
upstairs (and thus I /can/ commit); I'll keep chipping away at tidying this
stuff up in subsequent commits.

Tested:

* AR9344 (Wasp), 2G STA mode
2019-05-05 04:56:37 +00:00
cy
e786d5adfb MFV r347136:
Update sqlite3-3.27.2 (3270200) --> sqlite3-3.28.0 (3280000)

MFC after:	3 days
Security:	CVE-2019-9937, CVE-2019-9936
2019-05-05 04:14:17 +00:00
cem
8140e9f055 x86: Implement MWAIT support for stopping a CPU
IPI_STOP is used after panic or when ddb is entered manually.  MONITOR/
MWAIT allows CPUs that support the feature to sleep in a low power way
instead of spinning.  Something similar is already used at idle.

It is perhaps especially useful in oversubscribed VM environments, and is
safe to use even if the panic/ddb thread is not the BSP.  (Except in the
presence of MWAIT errata, which are detected automatically on platforms with
known wakeup problems.)

It can be tuned/sysctled with "machdep.stop_mwait," which defaults to 0
(off).  This commit also introduces the tunable
"machdep.mwait_cpustop_broken," which defaults to 0, unless the CPU has
known errata, but may be set to "1" in loader.conf to signal that mwait
wakeup is broken on CPUs FreeBSD does not yet know about.

Unfortunately, Bhyve doesn't yet support MONITOR extensions, so this doesn't
help bhyve hypervisors running FreeBSD guests.

Submitted by:   Anton Rang <rang AT acm.org> (earlier version)
Reviewed by:	kib
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D20135
2019-05-04 20:34:26 +00:00
kib
58510286a0 arm64: Properly restore PAN when done with userspace access in casueword.
Approved by:	andrew
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-05-04 19:40:30 +00:00
mjg
e4f7c7c91c sysv: get rid of fork/exit hooks if the code is compiled in
Sponsored by:	The FreeBSD Foundation
2019-05-04 19:05:30 +00:00
mjg
977b479291 Annotate nprocs with __exclusive_cache_line
Sponsored by:	The FreeBSD Foundation
2019-05-04 19:04:17 +00:00
mckusick
54d65ae934 Zero out the file directory entry metadata to reduce disk
scavenging disclosure.

Submitted by: David G. Lawrence <dg@dglawrence.com>
MFC after:    1 week
2019-05-04 18:00:57 +00:00