- Add RATELIMIT kernel configuration keyword which must be set to
enable the new functionality.
- Add support for hardware driven, Receive Side Scaling, RSS aware, rate
limited sendqueues and expose the functionality through the already
established SO_MAX_PACING_RATE setsockopt(). The API support rates in
the range from 1 to 4Gbytes/s which are suitable for regular TCP and
UDP streams. The setsockopt(2) manual page has been updated.
- Add rate limit function callback API to "struct ifnet" which supports
the following operations: if_snd_tag_alloc(), if_snd_tag_modify(),
if_snd_tag_query() and if_snd_tag_free().
- Add support to ifconfig to view, set and clear the IFCAP_TXRTLMT
flag, which tells if a network driver supports rate limiting or not.
- This patch also adds support for rate limiting through VLAN and LAGG
intermediate network devices.
- How rate limiting works:
1) The userspace application calls setsockopt() after accepting or
making a new connection to set the rate which is then stored in the
socket structure in the kernel. Later on when packets are transmitted
a check is made in the transmit path for rate changes. A rate change
implies a non-blocking ifp->if_snd_tag_alloc() call will be made to the
destination network interface, which then sets up a custom sendqueue
with the given rate limitation parameter. A "struct m_snd_tag" pointer is
returned which serves as a "snd_tag" hint in the m_pkthdr for the
subsequently transmitted mbufs.
2) When the network driver sees the "m->m_pkthdr.snd_tag" different
from NULL, it will move the packets into a designated rate limited sendqueue
given by the snd_tag pointer. It is up to the individual drivers how the rate
limited traffic will be rate limited.
3) Route changes are detected by the NIC drivers in the ifp->if_transmit()
routine when the ifnet pointer in the incoming snd_tag mismatches the
one of the network interface. The network adapter frees the mbuf and
returns EAGAIN which causes the ip_output() to release and clear the send
tag. Upon next ip_output() a new "snd_tag" will be tried allocated.
4) When the PCB is detached the custom sendqueue will be released by a
non-blocking ifp->if_snd_tag_free() call to the currently bound network
interface.
Reviewed by: wblock (manpages), adrian, gallatin, scottl (network)
Differential Revision: https://reviews.freebsd.org/D3687
Sponsored by: Mellanox Technologies
MFC after: 3 months
FC-Tape provides additional link level error recovery, and is
highly recommended for tape devices. It will only be turned on for
a given target if the target supports it.
Without this setting, we default to whatever FC-Tape setting is in
NVRAM on the card.
This can be overridden by setting the following loader tunable, for
example for isp0:
hint.isp.0.nofctape=1
sys/conf/options:
Add a new kernel config option, ISP_FCTAPE_OFF, that
defaults the FC-Tape configuration to off.
sys/dev/isp/isp_pci.c:
If ISP_FCTAPE_OFF is defined, turn off FC-Tape. Otherwise,
turn it on if the card supports it.
share/man/man4/isp.4:
Add a description of FC-Tape to the isp(4) man page.
Add descriptions of the fctape and nofctape options, as well as the
ISP_FCTAPE_OFF kernel configuration option.
Add the ispfw module and kernel drivers to the suggested
configurations at the top of the man page so that users are less
likely to leave it out. The driver works well with the included
firmware, but may not work at all with whatever firmware the user
has flashed on their card.
MFC after: 3 days
Sponsored by: Spectra Logic
Changes include modifications in kernel crash dump routines, dumpon(8) and
savecore(8). A new tool called decryptcore(8) was added.
A new DIOCSKERNELDUMP I/O control was added to send a kernel crash dump
configuration in the diocskerneldump_arg structure to the kernel.
The old DIOCSKERNELDUMP I/O control was renamed to DIOCSKERNELDUMP_FREEBSD11 for
backward ABI compatibility.
dumpon(8) generates an one-time random symmetric key and encrypts it using
an RSA public key in capability mode. Currently only AES-256-CBC is supported
but EKCD was designed to implement support for other algorithms in the future.
The public key is chosen using the -k flag. The dumpon rc(8) script can do this
automatically during startup using the dumppubkey rc.conf(5) variable. Once the
keys are calculated dumpon sends them to the kernel via DIOCSKERNELDUMP I/O
control.
When the kernel receives the DIOCSKERNELDUMP I/O control it generates a random
IV and sets up the key schedule for the specified algorithm. Each time the
kernel tries to write a crash dump to the dump device, the IV is replaced by
a SHA-256 hash of the previous value. This is intended to make a possible
differential cryptanalysis harder since it is possible to write multiple crash
dumps without reboot by repeating the following commands:
# sysctl debug.kdb.enter=1
db> call doadump(0)
db> continue
# savecore
A kernel dump key consists of an algorithm identifier, an IV and an encrypted
symmetric key. The kernel dump key size is included in a kernel dump header.
The size is an unsigned 32-bit integer and it is aligned to a block size.
The header structure has 512 bytes to match the block size so it was required to
make a panic string 4 bytes shorter to add a new field to the header structure.
If the kernel dump key size in the header is nonzero it is assumed that the
kernel dump key is placed after the first header on the dump device and the core
dump is encrypted.
Separate functions were implemented to write the kernel dump header and the
kernel dump key as they need to be unencrypted. The dump_write function encrypts
data if the kernel was compiled with the EKCD option. Encrypted kernel textdumps
are not supported due to the way they are constructed which makes it impossible
to use the CBC mode for encryption. It should be also noted that textdumps don't
contain sensitive data by design as a user decides what information should be
dumped.
savecore(8) writes the kernel dump key to a key.# file if its size in the header
is nonzero. # is the number of the current core dump.
decryptcore(8) decrypts the core dump using a private RSA key and the kernel
dump key. This is performed by a child process in capability mode.
If the decryption was not successful the parent process removes a partially
decrypted core dump.
Description on how to encrypt crash dumps was added to the decryptcore(8),
dumpon(8), rc.conf(5) and savecore(8) manual pages.
EKCD was tested on amd64 using bhyve and i386, mipsel and sparc64 using QEMU.
The feature still has to be tested on arm and arm64 as it wasn't possible to run
FreeBSD due to the problems with QEMU emulation and lack of hardware.
Designed by: def, pjd
Reviewed by: cem, oshogbo, pjd
Partial review: delphij, emaste, jhb, kib
Approved by: pjd (mentor)
Differential Revision: https://reviews.freebsd.org/D4712
If bufring is used for per-TX ring descs, don't update "available"
counter, which is only used to help debugging.
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8674
The default (512) wastes quite a bit of space which doesn't really buy
us much on highly embedded systems which don't take a lot of locks in
parallel.
This makes it at least build time configurable so people can experiment.
Upstream the BUF_TRACKING and FULL_BUF_TRACKING buffer debugging code.
This can be handy in tracking down what code touched hung bios and bufs
last. The full history is especially useful, but adds enough bloat that
it shouldn't be enabled in release builds.
Function names (or arbitrary string constants) are tracked in a
fixed-size ring in bufs. Bios gain a pointer to the upper buf for
tracking. SCSI CCBs gain a pointer to the upper bio for tracking.
Reviewed by: markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D8366
All devices:
- add support for rate adaptation via ieee80211_amrr(9);
- use short preamble for transmitted frames when needed;
- multi-bss support:
* for RTL8821AU: 2 VAPs at the same time;
* other: 1 any VAP + 1 sta VAP.
RTL8188CE:
- fix IQ calibration bug (reason of significant speed degradation);
- add h/w crypto acceleration support.
USB:
- A-MPDU Tx support;
- short GI support;
Other:
- add support for RTL8812AU / RTL8821AU chipsets
(a/b/g/n only; no ac yet);
- split merged code into subparts:
* bus glue (usb/*, pci/*, rtl*/usb/*, rtl*/pci/*)
* common (if_rtwn*)
* chip-specific (rtl*/*)
- various other bugfixes.
Due to code reorganization, module names / requirements were changed too:
urtwn urtwnfw -> rtwn rtwn_usb rtwnfw
rtwn rtwnfw -> rtwn rtwn_pci rtwnfw
Tested with RTL8188CE, RTL8188CUS, RTL8188EU and RTL8821AU.
Tested by: kevlo, garga,
Peter Garshtja <peter.garshtja@ambient-md.com>,
Kevin McAleavey <kevin.mcaleavey@knosproject.com>,
Ilias-Dimitrios Vrachnis <id@vrachnis.com>,
<otacilio.neto@bsd.com.br>
Relnotes: yes
to add actions that run when a TCP frame is sent or received on a TCP
session in the ESTABLISHED state. In the base tree, this functionality is
only used for the h_ertt module, which is used by the cc_cdg, cc_chd, cc_hd,
and cc_vegas congestion control modules.
Presently, we incur overhead to check for hooks each time a TCP frame is
sent or received on an ESTABLISHED TCP session.
This change adds a new compile-time option (TCP_HHOOK) to determine whether
to include the hhook(9) framework for TCP. To retain backwards
compatibility, I added the TCP_HHOOK option to every configuration file that
already defined "options INET". (Therefore, this patch introduces no
functional change. In order to see a functional difference, you need to
compile a custom kernel without the TCP_HHOOK option.) This change will
allow users to easily exclude this functionality from their kernel, should
they wish to do so.
Note that any users who use a custom kernel configuration and use one of the
congestion control modules listed above will need to add the TCP_HHOOK
option to their kernel configuration.
Reviewed by: rrs, lstewart, hiren (previous version), sjg (makefiles only)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D8185
- Convert "options EVDEV" to "device evdev" and "device uinput", add
modules for both new devices. They are isolated subsystems and do not
require any compile-time changes to general kernel subsytems
- For hybrid drivers that have evdev as an optional way to deliver input
events add option EVDEV_SUPPORT. Update all existing hybrid drivers
to use it instead of EVDEV
- Remove no-op DECLARE_MODULE in evdev, it's not required, MODULE_VERSION
is enough
- Add evdev module dependency to uinput
Submitted by: Vladimir Kondratiev <wulf@cicgroup.ru>
evdev is a generic input event interface compatible with Linux
evdev API at ioctl level. It allows using unmodified (apart from
header name) input evdev drivers in Xorg, Wayland, Qt.
This commit has only generic kernel API. evdev support for individual
hardware drivers like ukbd, ums, atkbd, etc. will be committed later.
Project was started by Jakub Klama as part of GSoC 2014. Jakub's
evdev implementation was later used as a base, updated and finished
by Vladimir Kondratiev.
Submitted by: Vladimir Kondratiev <wulf@cicgroup.ru>
Reviewed by: adrian, hans
Differential Revision: https://reviews.freebsd.org/D6998
Essentially, this is a literal copy of the code in sys/compat/cloudabi64,
except that it now makes use of 32-bits datatypes and limits. In
sys/conf/files, we now need to take care to build the code in
sys/compat/cloudabi if either COMPAT_CLOUDABI32 or COMPAT_CLOUDABI64 is
turned on.
This change does not yet include any of the CPU dependent bits. Right
now I have implementations for running i386 binaries both on i386 and
x86-64, which I will send out for review separately.
The wl(4) driver supports pre-802.11 PCCard wireless adapters that
are slower than 802.11b. They do not work with any of the 802.11
framework and the driver hasn't been reported to actually work in a
long time.
Relnotes: yes
The module works together with ipfw(4) and implemented as its external
action module.
Stateless NAT64 registers external action with name nat64stl. This
keyword should be used to create NAT64 instance and to address this
instance in rules. Stateless NAT64 uses two lookup tables with mapped
IPv4->IPv6 and IPv6->IPv4 addresses to perform translation.
A configuration of instance should looks like this:
1. Create lookup tables:
# ipfw table T46 create type addr valtype ipv6
# ipfw table T64 create type addr valtype ipv4
2. Fill T46 and T64 tables.
3. Add rule to allow neighbor solicitation and advertisement:
# ipfw add allow icmp6 from any to any icmp6types 135,136
4. Create NAT64 instance:
# ipfw nat64stl NAT create table4 T46 table6 T64
5. Add rules that matches the traffic:
# ipfw add nat64stl NAT ip from any to table(T46)
# ipfw add nat64stl NAT ip from table(T64) to 64:ff9b::/96
6. Configure DNS64 for IPv6 clients and add route to 64:ff9b::/96
via NAT64 host.
Stateful NAT64 registers external action with name nat64lsn. The only
one option required to create nat64lsn instance - prefix4. It defines
the pool of IPv4 addresses used for translation.
A configuration of instance should looks like this:
1. Add rule to allow neighbor solicitation and advertisement:
# ipfw add allow icmp6 from any to any icmp6types 135,136
2. Create NAT64 instance:
# ipfw nat64lsn NAT create prefix4 A.B.C.D/28
3. Add rules that matches the traffic:
# ipfw add nat64lsn NAT ip from any to A.B.C.D/28
# ipfw add nat64lsn NAT ip6 from any to 64:ff9b::/96
4. Configure DNS64 for IPv6 clients and add route to 64:ff9b::/96
via NAT64 host.
Obtained from: Yandex LLC
Relnotes: yes
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D6434
number of core files allowed by a particular process when using the %I core
file name pattern.
Sanity check at compile time to ensure the value is within the valid range of
0-10.
Reviewed by: jtl, sjg
Approved by: sjg (mentor)
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D6812
as defined in RFC 6296. The module works together with ipfw(4) and
implemented as its external action module. When it is loaded, it registers
as eaction and can be used in rules. The usage pattern is similar to
ipfw_nat(4). All matched by rule traffic goes to the NPT module.
Reviewed by: hrs
Obtained from: Yandex LLC
MFC after: 1 month
Relnotes: yes
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D6420
"iflib is a library to eliminate the need for frequently duplicated device
independent logic propagated (poorly) across many network drivers."
Participation is purely optional. The IFLIB kernel config option is
provided for drivers that want to transition between legacy and iflib
modes of operation. ixl and ixgbe driver conversions will be committed
shortly. We hope to see participation from the Broadcom and maybe
Chelsio drivers in the near future.
Submitted by: mmacy@nextbsd.org
Reviewed by: gallatin
Differential Revision: D5211
It has no counterpart among the other lock primitives and has been a
no-op for years. Mutex consistency checks are generally done whenver
INVARIANTS is enabled.
There are 5 logging levels:
* ERROR
* WARN
* INFO
* DEBUG
* TRACE
There are 2 logging context:
* with
* without device
DEBUG and TRACE records are printed only if bootverbose.
Logging records are printed with source code line information if acceptable
logging level is DEBUG or TRACE.
Submitted by: Michael Zhilin <mizhka@gmail.com>
Differential Revision: https://reviews.freebsd.org/D6247
Currently, Application Processors (non-boot CPUs) are started by
MD code at SI_SUB_CPU, but they are kept waiting in a "pen" until
SI_SUB_SMP at which point they are released to run kernel threads.
SI_SUB_SMP is one of the last SYSINIT levels, so APs don't enter
the scheduler and start running threads until fairly late in the
boot.
This change moves SI_SUB_SMP up to just before software interrupt
threads are created allowing the APs to start executing kernel
threads much sooner (before any devices are probed). This allows
several initialization routines that need to perform initialization
on all CPUs to now perform that initialization in one step rather
than having to defer the AP initialization to a second SYSINIT run
at SI_SUB_SMP. It also permits all CPUs to be available for
handling interrupts before any devices are probed.
This last feature fixes a problem on with interrupt vector exhaustion.
Specifically, in the old model all device interrupts were routed
onto the boot CPU during boot. Later after the APs were released at
SI_SUB_SMP, interrupts were redistributed across all CPUs.
However, several drivers for multiqueue hardware allocate N interrupts
per CPU in the system. In a system with many CPUs, just a few drivers
doing this could exhaust the available pool of interrupt vectors on
the boot CPU as each driver was allocating N * mp_ncpu vectors on the
boot CPU. Now, drivers will allocate interrupts on their desired CPUs
during boot meaning that only N interrupts are allocated from the boot
CPU instead of N * mp_ncpu.
Some other bits of code can also be simplified as smp_started is
now true much earlier and will now always be true for these bits of
code. This removes the need to treat the single-CPU boot environment
as a special case.
As a transition aid, the new behavior is available under a new kernel
option (EARLY_AP_STARTUP). This will allow the option to be turned off
if need be during initial testing. I plan to enable this on x86 by
default in a followup commit in the next few days and to have all
platforms moved over before 11.0. Once the transition is complete,
the option will be removed along with the !EARLY_AP_STARTUP code.
These changes have only been tested on x86. Other platform maintainers
are encouraged to port their architectures over as well. The main
things to check for are any uses of smp_started in MD code that can be
simplified and SI_SUB_SMP SYSINITs in MD code that can be removed in
the EARLY_AP_STARTUP case (e.g. the interrupt shuffling).
PR: kern/199321
Reviewed by: markj, gnn, kib
Sponsored by: Netflix
PCI-express HotPlug support is implemented via bits in the slot
registers of the PCI-express capability of the downstream port along
with an interrupt that triggers when bits in the slot status register
change.
This is implemented for FreeBSD by adding HotPlug support to the
PCI-PCI bridge driver which attaches to the virtual PCI-PCI bridges
representing downstream ports on HotPlug slots. The PCI-PCI bridge
driver registers an interrupt handler to receive HotPlug events. It
also uses the slot registers to determine the current HotPlug state
and drive an internal HotPlug state machine. For simplicty of
implementation, the PCI-PCI bridge device detaches and deletes the
child PCI device when a card is removed from a slot and creates and
attaches a PCI child device when a card is inserted into the slot.
The PCI-PCI bridge driver provides a bus_child_present which claims
that child devices are present on HotPlug-capable slots only when a
card is inserted. Rather than requiring a timeout in the RC for
config accesses to not-present children, the pcib_read/write_config
methods fail all requests when a card is not present (or not yet
ready).
These changes include support for various optional HotPlug
capabilities such as a power controller, mechanical latch,
electro-mechanical interlock, indicators, and an attention button.
It also includes support for devices which require waiting for
command completion events before initiating a subsequent HotPlug
command. However, it has only been tested on ExpressCard systems
which support surprise removal and have none of these optional
capabilities.
PCI-express HotPlug support is conditional on the PCI_HP option
which is enabled by default on arm64, x86, and powerpc.
Reviewed by: adrian, imp, vangyzen (older versions)
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D6136
as before. The common scheduling bits have moved from inline code in
each of the CAM periph drivers into a library that implements the
default scheduling.
In addition, a number of rate-limiting and I/O preference options can
be enabled by adding CAM_IOSCHED_NETFLIX to your config file. A number
of extra stats are also maintained. CAM_IOSCHED_NETFLIX isn't on by
default because it uses a separate BIO_READ and BIO_WRITE queue, so
doesn't honor BIO_ORDERED between these two types of operations. We
already didn't honor it for BIO_DELETE, and we don't depend on
BIO_ORDERED between reads and writes anywhere in the system (it is
currently used with BIO_FLUSH in ZFS to make sure some writes are
complete before others start and as a poor-man's soft dependency in
one place in UFS where we won't be issuing READs until after the
operation completes). However, out of an abundance of caution, it
isn't enabled by default.
Plus, this also brings in NCQ TRIM support for those SSDs that support
it. A black list is also provided for known rogues that use NCQ trim
as an excuse to corrupt the drive. It was difficult to separate out
into a separate commit.
This code has run in production at Netflix for over a year now.
Sponsored by: Netflix, Inc
Differential Revision: https://reviews.freebsd.org/D4609
VM_NUMA_ALLOC is used to enable use of domain-aware memory allocation in
the virtual memory system. DEVICE_NUMA is used to enable affinity
reporting for devices such as bus_get_domain().
MAXMEMDOM must still be set to a value greater than for any NUMA support
to be effective. Note that 'cpuset -gd' always works if MAXMEMDOM is
enabled and the system supports NUMA.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D5782
improve cancellation robustness.
Introduce a new file operation, fo_aio_queue, which is responsible for
queueing and completing an asynchronous I/O request for a given file.
The AIO subystem now exports library of routines to manipulate AIO
requests as well as the ability to run a handler function in the
"default" pool of AIO daemons to service a request.
A default implementation for file types which do not include an
fo_aio_queue method queues requests to the "default" pool invoking the
fo_read or fo_write methods as before.
The AIO subsystem permits file types to install a private "cancel"
routine when a request is queued to permit safe dequeueing and cleanup
of cancelled requests.
Sockets now use their own pool of AIO daemons and service per-socket
requests in FIFO order. Socket requests will not block indefinitely
permitting timely cancellation of all requests.
Due to the now-tight coupling of the AIO subsystem with file types,
the AIO subsystem is now a standard part of all kernels. The VFS_AIO
kernel option and aio.ko module are gone.
Many file types may block indefinitely in their fo_read or fo_write
callbacks resulting in a hung AIO daemon. This can result in hung
user processes (when processes attempt to cancel all outstanding
requests during exit) or a hung system. To protect against this, AIO
requests are only permitted for known "safe" files by default. AIO
requests for all file types can be enabled by setting the new
vfs.aio.enable_usafe sysctl to a non-zero value. The AIO tests have
been updated to skip operations on unsafe file types if the sysctl is
zero.
Currently, AIO requests on sockets and raw disks are considered safe
and are enabled by default. aio_mlock() is also enabled by default.
Reviewed by: cem, jilles
Discussed with: kib (earlier version)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D5289
- Add URTWN_WITHOUT_UCODE option (will disable any firmware specific code
when set).
- Do not exclude the driver from build when MK_SOURCELESS_UCODE is set
(URTWN_WITHOUT_UCODE will be enforced unconditionally).
- Do not abort initialization when firmware cannot be loaded;
behave like the URTWN_WITHOUT_UCODE option was set.
- Drop some unused variables from urtwn_softc structure.
Tested with RTL8188EU and RTL8188CUS in HOSTAP and STA modes.
Reviewed by: kevlo
Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D4849
a mips big-endian board.
This is (hopefully! ish!) a temporary change until a slightly better way
can be found to express this without a config option.
Tested:
* BUFFALO WZR-HP-G300NH 1stGen (by submitter)
Submitted by: Mori Hiroki <yamori813@yahoo.co.jp>
support frameworks(i.e. reset/regulators/phy/tsensors/fuses...).
The clock framework significantly simplifies handling of complex clock
structures found in modern SoCs. It provides the unified consumers
interface, holds and manages actual clock topology, frequency and gating.
It's tested on three different ARM boards (Nvidia Tegra TK1, Inforce 6410 and
Odroid XU2) and on one MIPS board (Creator Ci20) by kan@.
The framework is still far from perfect and probably doesn't have stable
interface yet, but we want to start testing it on more real boards and
different architectures.
Reviewed by: ian, kan (earlier version)
TFO is disabled by default in the kernel build. See the top comment
in sys/netinet/tcp_fastopen.c for implementation particulars.
Reviewed by: gnn, jch, stas
MFC after: 3 days
Sponsored by: Verisign, Inc.
Differential Revision: https://reviews.freebsd.org/D4350
Use hhook(9) framework to achieve ability of loading and unloading
if_enc(4) kernel module. INET and INET6 code on initialization registers
two helper hooks points in the kernel. if_enc(4) module uses these helper
hook points and registers its hooks. IPSEC code uses these hhook points
to call helper hooks implemented in if_enc(4).
It turns out on a 16550 w/ a 25MHz SoC reference clock you get a little
over 3% error at 115200 baud, which causes this to fail.
Just .. cope. Things cope these days.
Default to 30 (3.0%) as before, but allow UART_DEV_TOLERANCE_PCT to be
set at build time to change that.
packets and/or state transitions from each TCP socket. That would help with
narrowing down certain problems we see in the field that are hard to reproduce
without understanding the history of how we got into a certain state. This
change provides just that.
It saves copies of the last N packets in a list in the tcpcb. When the tcpcb is
destroyed, the list is freed. I thought this was likely to be more
performance-friendly than saving copies of the tcpcb. Plus, with the packets,
you should be able to reverse-engineer what happened to the tcpcb.
To enable the feature, you will need to compile a kernel with the TCPPCAP
option. Even then, the feature defaults to being deactivated. You can activate
it by setting a positive value for the number of captured packets. You can do
that on either a global basis or on a per-socket basis (via a setsockopt call).
There is no way to get the packets out of the kernel other than using kmem or
getting a coredump. I thought that would help some of the legal/privacy concerns
regarding such a feature. However, it should be possible to add a future effort
to export them in PCAP format.
I tested this at low scale, and found that there were no mbuf leaks and the peak
mbuf usage appeared to be unchanged with and without the feature.
The main performance concern I can envision is the number of mbufs that would be
used on systems with a large number of sockets. If you save five packets per
direction per socket and have 3,000 sockets, that will consume at least 30,000
mbufs just to keep these packets. I tried to reduce the concerns associated with
this by limiting the number of clusters (not mbufs) that could be used for this
feature. Again, in my testing, that appears to work correctly.
Differential Revision: D3100
Submitted by: Jonathan Looney <jlooney at juniper dot net>
Reviewed by: gnn, hiren
RANDOM_LOADABLE and RANDOM_YARROW's definitions from opt_random.h to
opt_global.h
This unbreaks `make depend` in sys/modules with multiple drivers (tmpfs, etc)
after r286839
X-MFC with: r286839
Reviewed by: imp
Submitted by: lwhsu
Differential Revision: D3486
Provide and document the RANDOM_ENABLE_UMA option.
Change RANDOM_FAST to RANDOM_UMA to clarify the harvesting.
Remove RANDOM_DEBUG option, replace with SDT probes. These will be of
use to folks measuring the harvesting effect when deciding whether to
use RANDOM_ENABLE_UMA.
Requested by: scottl and others.
Approved by: so (/dev/random blanket)
Differential Revision: https://reviews.freebsd.org/D3197