This was purely automatically massaged... some parts are still imperfect,
but this is close enough to make it more readable/easy to work on.
Unfortunately the vt/syscons/kdb situation slightly complicates changes to
tty locking, so some work will need to be done to remediate that.
tightening constraints on busy as a precursor to lockless page lookup and
should largely be a NOP for these cases.
Reviewed by: alc, kib, markj
Differential Revision: https://reviews.freebsd.org/D22611
the sched_preempt() switch optimization and causes the sched lock to be dropped
and immediately reacquired.
Reviewed by: jhb, kib, mav, markj (with changes)
Differential Revision: https://reviews.freebsd.org/D22623
This makes it possible to retrieve per-connection statistical
information such as the receive window size, RTT, or goodput,
using a newly added TCP_STATS getsockopt(3) option, and extract
them using the stats_voistat_fetch(3) API.
See the net/tcprtt port for an example consumer of this API.
Compared to the existing TCP_INFO system, the main differences
are that this mechanism is easy to extend without breaking ABI,
and provides statistical information instead of raw "snapshots"
of values at a given point in time. stats(3) is more generic
and can be used in both userland and the kernel.
Reviewed by: thj
Tested by: thj
Obtained from: Netflix
Relnotes: yes
Sponsored by: Klara Inc, Netflix
Differential Revision: https://reviews.freebsd.org/D20655
Some of the printf statements only use LF to get a newline. However, a CR character is also required for the serial console to print debug logs in a nice way.
Fix those code locations that only use LF, by adding a CR character.
Reviewed by: markj, aleksandr.fedorov@itglobal.com
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D22552
My changes in 351599 (kindly committed by avg) made the cd(4) media check
asynchronous to avoid a sleep while holding a mutex.
There was a difficult to reproduce bug with those changes that caused a
hang on boot on some single processor machines/VMs. Leandro Lupori
managed to reproduce the bug, diagnose it, and supplied a patch! Here is
his analysis, from the PR:
======
I was able to reproduce the problem described in comment#14.
Actually, I wasn't trying to reproduce it, I just started seeing it a few
weeks ago, in CURRENT.
I can reproduce it consistently, by using QEMU to run a PowerPC64 VM with a
single core/thread (-smp 1).
It happens only when there is no media in the emulated CD-ROM, a device
that QEMU adds by default, unless -nodefaults is specified in command line.
I've debugged it and this is what I've found:
1- After the CD probe is successful, GEOM will try to open the device,
which will end up calling cdcheckmedia(), that sets CD state to
CD_STATE_MEDIA_PREVENT.
2- Next, scsi_prevent() is executed and succeeds, the CD_FLAG_DISC_LOCKED
flag is set and CD state moves to CD_STATE_MEDIA_SIZE.
3- Next, scsi_read_capacity() is executed and fails, state is set to
CD_STATE_MEDIA_ALLOW, cdmediaprobedone() is called and wakes up
cdcheckmedia().
4- Then, when cdstart() is invoked to process CD_STATE_MEDIA_ALLOW, it
first checks if CD_FLAG_DISC_LOCKED is set, and if so skips directly to
CD_STATE_MEDIA_SIZE state. This will repeat the steps of bullet 3, entering
an infinite MEDIA_SIZE command loop.
When there is a least another core/thread, the GEOM thread that performed
the initial cdopen() will get scheduled again, closing the CD device, that
will call cdprevent(PR_ALLOW) that clears the CD_FLAG_DISC_LOCKED flag and
breaks the loop.
So, apparently, the problem is CD_STATE_MEDIA_ALLOW being skipped when
CD_FLAG_DISC_LOCKED is set. If I understand correctly, in this case, the
state should be advanced to CD_STATE_MEDIA size only when the current state
is CD_STATE_MEDIA_PREVENT.
=====
PR: kern/219857
Submitted by: Leandro Lupori <leandro.lupori@gmail.com>
MFC after: 1 week
struct gpio_pin. It turns out these two sets of flags are completely
unrelated to each other.
Also, update the comment for GPIO_ACTIVE_LOW to reflect the fact that it
does get set, somewhat unobviously, by code that parses FDT data. The bits
from the FDT cell containing flags are just copied to gpiobus_pin.flags, so
there's never any obvious reference to the symbol GPIO_ACTIVE_LOW being
stored into the flags field.
After discussing with mmel@, it was clear this is insufficient to address
all the needs. mmel@ will commit his original patch, from
https://reviews.freebsd.org/D13861, and the additions needed from r354714
will be made afterward.
Requested by: mmel
Sponsored by: Juniper Networks, Inc.
When using sysrc to modify a file, the file should be created silently.
However, with the introduction of SVN r335280, an error of "No such file
or directory" would appear despite everything else working as-expected.
The nature of this spurious error is that SVN r335280 did not check if
the file exists first, before trying to fixup the line-endings in the
file just prior to modification.
PR: bin/240875
Reported by: Jose Luis Duran
MFC after: 3 days
FDT bindings document for gpio-i2c devices.
Using the gpio_pin_* functions to acquire/release/manipulate gpio pins
removes the constraint that both gpio pins must belong to the same gpio
controller/bank, and that the gpioiic instance must be a child of gpiobus.
Removing those constraints allows the driver to be fully compatible with
the modern dts bindings for a gpio bitbanged i2c bus.
For hinted attachment, the two gpio pins still must be on the same gpiobus,
and the device instance must be a child of that bus. This preserves
compatibility for existing installations that have use gpioiic(4) with hints.
This lets us print, for example, the user's trap frame when a panic occurs.
The frame address is given in the backtrace at the trap point, which can
then be passed to 'show frame'. This is useful for debugging as it can show
inputs that lead to a panic or fault. It can also be used to print trap
frames from other CPUs that get stuck.
i386 already has a similar command, but no others do.
that they can be used by drivers on non-FDT-configured systems. Only the
functions related to acquiring pins by parsing FDT data remain in
ofw_gpiobus. Also, add two new functions for acquiring gpio pins based on
child device_t and index, or on the bus device_t and pin number. And
finally, defer reserving pins for gpiobus children until they acquire the
pin, rather than reserving them as soon as the child is added (before it's
even known whether the child will attach).
This will allow drivers configured with hints (or any other mechanism) to
use the same code as drivers configured via FDT data. Until now, a hinted
driver and an FDT driver had to be two completely different sets of code,
because hinted drivers could only use gpiobus calls to manipulate pins,
while fdt-configured drivers could not use that API (due to not always being
children of the bus that owns the pins) and had to use the newer
gpio_pin_xxxx() functions. Now drivers can be written in the more
traditional form, where most of the code is shared and only the resource
acquisition code at attachment time changes.
This allows adding more ECN related flags in the future.
No functional change intended.
Submitted by: Richard Scheffenegger
Reviewed by: rrs@, tuexen@
Differential Revision: https://reviews.freebsd.org/D22497
to make them aligned.
Submitted by: Richard Scheffenegger
Reviewed by: rgrimes@, rrs@, tuexen@
Differential Revision: https://reviews.freebsd.org/D22428
As part of my journey to make it easy to determine what's relying on tty
bits, remove a couple more. Some of these just outright didn't need it,
while others did rely on <sys/tty.h> pollution for mutex headers.
The handle value is stable for all shadow objects in the inheritance
chain. This allows to avoid descending the shadow chain to get to the
bottom of it in vm_map_entry_set_vnode_text(), and eliminate
corresponding object relocking which appeared to be contending.
Change vm_object_allocate_anon() and vm_object_shadow() to handle more
of the cred/charge initialization for the new shadow object, in
addition to set up the handle.
Reported by: jeff
Reviewed by: alc (previous version), jeff (previous version)
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differrential revision: https://reviews.freebsd.org/D22541
It was introduced by r290122, but no documentation was provided.
This is taken from https://reviews.freebsd.org/D21798, since it
is not related to the feature added there.
Submitted by: Richard Scheffenegger
MFC after: 1 week
to add support for L4S or SCE, which require processing of the IP TOS
field.
Submitted by: Richard Scheffenegger
Reviewed by: rgrimes@, rrs@, tuexen@
Differential Revision: https://reviews.freebsd.org/D22426
improvements, the ECN bits need to be exposed to the TCP SYNcache.
This change is a minimal modification to the function headers, without any
functional change intended.
Submitted by: Richard Scheffenegger
Reviewed by: rgrimes@, rrs@, tuexen@
Differential Revision: https://reviews.freebsd.org/D22436
RTT measurements, but also scheldule new ones for the future.
Submitted by: Julius Flohr
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D22547
No need to log all the commands in command ring but only the last one for which completion failed.
Reported by: np@freebsd.org
Reviewed by: np, markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22566
r354748-354750 replaced the KAME macros with m_pulldown() calls.
Contrary to the rest of the network stack m_len checks before m_pulldown()
were not put in placed (see r354748).
Put these m_len checks in place for now (to go along with the style of the
network stack since the initial commits). These are not put in for
performance but to avoid an error scenario (even though it also will help
performance at the moment as it avoid allocating an extra mbuf; not because
of the unconditional function call).
The observed error case went like this:
(1) an mbuf with M_EXT arrives and we call m_pullup() unconditionally on it.
(2) m_pullup() will call m_get() unless the requested length is larger than
MHLEN (in which case it'll m_freem() the perfectly fine mbuf) and migrate the
requested length of data and pkthdr into the new mbuf.
(3) If m_get() succeeds, a further m_pullup() call going over MHLEN will fail.
This was observed with failing auto-configuration as an RA packet of
200 bytes exceeded MHLEN and the m_pullup() called from nd6_ra_input()
dropped the mbuf.
(Re-)adding the m_len checks before m_pullup() calls avoids this problems
with mbufs using external storage for now.
MFC after: 3 weeks
Sponsored by: Netflix
Generally, it's preferred that an application fork/setsid if it doesn't want
to keep its controlling TTY, but it could be that a debugger is trying to
steal it instead -- so it would hook in, drop the controlling TTY, then do
some magic to set things up again. In this case, TIOCNOTTY is quite handy
and still respected by at least OpenBSD, NetBSD, and Linux as far as I can
tell.
I've dropped the note about obsoletion, as I intend to support TIOCNOTTY as
long as it doesn't impose a major burden.
Reviewed by: bcr (manpages), kib
Differential Revision: https://reviews.freebsd.org/D22572
Before this commit, the save-entropy script rotates entropy files
like logs. This involves creating a new file that holds the entropy
and renaming of all existing entropy files. However, the entropy
data do not really need to be kept in a particular order, and
replacing the oldest file is sufficient.
This commit replaces the rotation with a scan in the
[1..entropy_save_num] space that finds the first empty slot, or
the slot of the oldest file, and writes entropy into that slot.
This also fixes an issue that prevents save-entropy from saving
any entropy when there is one non-regular file in any slot as a
side effect.
Based on an earlier patch from peterj@.
PR: 134225
Reported by: peterj
Reviewed by: csprng (cem, markm)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22612
The previously used quiesce_all_cpus walks all CPUs and waits until curthread
can run on them. Even on contemporary machines this becomes a significant
problem under load when it can literally take minutes for the operation to
complete. With the patch the stall is normally less than 1 second.
Reviewed by: kib, jeff (previous version)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21740
A variant of this facility was already used by rmlocks where IPIs would
enforce ordering.
This allows to elide fences where they are rarely needed and the cost of
IPI (should it be necessary) is cheaper.
Reviewed by: kib, jeff (previous version)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21740
This allows bumping threadcount without taking the global devmtx lock.
In particular this eliminates contention on said lock while using bhyve
with multiple vms.
Reviewed by: kib
Tested by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D22548
