Commit Graph

35 Commits

Author SHA1 Message Date
Colin Percival
8b8a7c43a9 Instrument "boot holds" for the benefit of the TSLOG framework. These
are places where the "main thread" of the booting kernel (either the
thread which later becomes swapper or the thread which later becomes
init) has to stop and wait for action to take place in another thread
before continuing.

There are currently three such holds:
1. The intr_config_hooks SYSINIT waits for hooks registered via the
config_intrhook_establish function; this allows (typically) devices
which need interrupts enabled to complete their initialization to do
so before root is mounted.

2. The g_waitidle function waits for the GEOM event queue to be empty;
this ensures that all of the disks which have been attached have been
tasted before we attempt to mount root.

3. The vfs_mountroot_wait function (in addition to calling g_waitidle)
waits for holds registered via root_mount_hold; among other things, this
is used by the USB subsystem to ensure that we don't fail to mount root
if it's located on a USB disk which takes a while to probe.
2017-12-31 09:23:52 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Ian Lepore
2db14f97de Add config_intrhook_oneshot(): schedule an intrhook function and unregister
it automatically after it runs.

The config_intrhook mechanism allows a driver to stall the boot process
until device(s) required for booting are available, by not allowing system
inits to proceed until all intrhook functions have been unregistered.
Virtually all existing code simply unregisters from within the hook function
when it gets called.

This new function makes that common usage more convenient. Instead of
allocating and filling in a struct, passing it to a function that might (in
theory) fail, and checking the return code, now a driver can simply call
this cannot-fail routine, passing just the intrhook function and its arg.

Differential Revision:	https://reviews.freebsd.org/D11963
2017-08-13 18:10:24 +00:00
Ed Maste
69a2875821 Renumber license clauses in sys/kern to avoid skipping #3 2016-09-15 13:16:20 +00:00
John Baldwin
6226ec3ef8 Retire PCONFIG and leave the priority of thread0 alone when waiting for
interrupt config hooks to execute.
2011-01-06 22:09:37 +00:00
Justin T. Gibbs
5ef8fb65f9 Allow interrupt driven config hooks to be registered from config hook callbacks.
Interrupt driven configuration hooks serve two purposes: they are a
mechanism for registering for a callback that is invoked once interrupt
services are available, and they hold off root device selection so long
as any configuration hooks are still active.  Before this change, it was
not possible to safely register additional hooks from the context of a
configuration hook callback.  The need for this feature arises when
interrupts are required to discover new devices (e.g. access to the XenStore
to find para-virtualized devices) which in turn also require the ability
to hold off root device selection until some lengthy, interrupt driven,
configuration task has completed (e.g. Xen front/back device driver
negotiation).

More specifically, the mutex protecting the list of active configuration
hooks is never held during a callback, and static information is used
to ensure proper ordering and only a single callback to each hook even
when faced with registration or removal of a hook during an active run.

Sponsored by:	Spectra Logic Corporation
MFC after:      1 week.
2010-08-12 19:50:40 +00:00
Warner Losh
04d17b6283 Prefer ANSI function definitions to K&R ones. 2009-02-03 07:52:07 +00:00
Robert Watson
828e07694c If run_interrupt_driven_config_hooks() waits 360 seconds and INVARIANTS
is compiled into the kernel, then panic.

MFC after:	3 days
Discussed with:	scottl
2008-07-21 20:50:49 +00:00
Robert Watson
1cc2bd820b Rather than simply waiting silently and indefinitely for all
interrupt-driven configuration handlers to complete, print out a
diagnostic message every 60 second indicating which handlers are
still running.  Do this at most 5 times per run so as to avoid
scrolling out any useful information from the kernel message
buffer.

The interval of 60 seconds was selected based on a best guess as
to the nature of "long enough" and may want to be tuned higher
or lower depending on real-world tolerances.

MFC after:	3 days
Discussed with:	scottl
2008-07-19 19:08:35 +00:00
Robert Watson
51c0f94ed7 Add DDB "show conifhk" command, which lists hooks currently waiting
for completion in run_interrupt_driven_config_hooks().  This is
helpful when trying to figure out which device drivers have gone
into la-la land during boot-time autoconfiguration.

MFC after:	3 days
2008-07-19 12:12:54 +00:00
Robert Watson
237fdd787b In keeping with style(9)'s recommendations on macros, use a ';'
after each SYSINIT() macro invocation.  This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.

MFC after:	1 month
Discussed with:	imp, rink
2008-03-16 10:58:09 +00:00
Antoine Brodin
74727f1209 Remove a superfluous line in run_interrupt_driven_config_hooks(),
next_entry is already initialized during TAILQ_FOREACH_SAFE().

PR:		kern/119604
Approved by:	rwatson (mentor)
MFC after:	1 month
2008-02-15 21:54:21 +00:00
John Baldwin
9079458ad2 Add a mutex to protect the list of interrupt config hooks. We do assume
that the only remove hook operation that can occur while processing the
hooks is to remove the currently executing hook.  This should be safe as
the existing code has assumed this already for a long time now.

Reviewed by:	scottl
MFC after:	1 week
2006-07-19 18:53:56 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
Warner Losh
7f8a436ff2 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-05 21:03:37 +00:00
Poul-Henning Kamp
68f2d20b70 Revert stuff which accidentally ended up in the previous commit. 2003-07-22 10:36:36 +00:00
Poul-Henning Kamp
55d1d7034f Don't attempt to inline large functions mb_alloc() and mb_free(),
it more than doubles the text size of this file.

GCC has wisely ignored us on this previously
2003-07-22 10:24:41 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Jake Burkholder
e39756439c Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
Jake Burkholder
740a1973a6 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
Nick Hibma
3e2c6ca3b9 Removal of sys/device.h
- Move intrhook stuff into kernel.h
- Remove all occurrences of #device <device.h>
- Add kernel.h were necessary (nowhere)
- delete device.h

This file contained the structures for cfdata (old style config) and is no
longer used. It was included by most drivers.

It confuses the remote debugger as the definition of 'struct device' in
device.h is found before the one in bus_private.h.
1999-10-05 21:19:41 +00:00
Nick Hibma
879eff8ee6 Change explicit use of the queue fields into use of the definitions
in queue.h.

Change the name of two variables for consistency.

Reviewed-By:	peter
1999-09-26 18:48:53 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Peter Wemm
fc51d58e62 Fix a very long standing bug in run_interrupt_driven_config_hooks(). It
was fetching the next pointer from memory that could have been free()'d.
1999-04-25 22:13:34 +00:00
Peter Wemm
2072df97aa GC some unused code. 1999-04-17 09:12:35 +00:00
Peter Wemm
e91896117b Well folks, this is it - The second stage of the removal for build support
for LKM's..
1999-04-17 08:36:07 +00:00
Eivind Eklund
5526d2d920 Split DIAGNOSTIC -> DIAGNOSTIC, INVARIANTS, and INVARIANT_SUPPORT as
discussed on -hackers.

Introduce 'KASSERT(assertion, ("panic message", args))' for simple
check + panic.

Reviewed by:	msmith
1999-01-08 17:31:30 +00:00
Archie Cobbs
2127f26023 Examine all occurrences of sprintf(), strcat(), and str[n]cpy()
for possible buffer overflow problems. Replaced most sprintf()'s
with snprintf(); for others cases, added terminating NUL bytes where
appropriate, replaced constants like "16" with sizeof(), etc.

These changes include several bug fixes, but most changes are for
maintainability's sake. Any instance where it wasn't "immediately
obvious" that a buffer overflow could not occur was made safer.

Reviewed by:	Bruce Evans <bde@zeta.org.au>
Reviewed by:	Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by:	Mike Spengler <mks@networkcs.com>
1998-12-04 22:54:57 +00:00
Bruce Evans
e4474ce8bf Removed an unused #include. Ifdefed a conditionally used #include. 1997-11-18 12:43:41 +00:00
Justin T. Gibbs
ab36c06737 init_main.c subr_autoconf.c:
Add support for "interrupt driven configuration hooks".
	A component of the kernel can register a hook, most likely
	during auto-configuration, and receive a callback once
	interrupt services are available.  This callback will occur before
	the root and dump devices are configured, so the configuration
	task can affect the selection of those two devices or complete
	any tasks that need to be performed prior to launching init.
	System boot is posponed so long as a hook is registered.  The
	hook owner is responsible for removing the hook once their task
	is complete or the system boot can continue.

kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c:
	Change the interface and implementation for the kernel callout
	service.  The new implemntaion is based on the work of
	Adam M. Costello and George Varghese, published in a technical
	report entitled "Redesigning the BSD Callout and Timer Facilities".
	The interface used in FreeBSD is a little different than the one
	outlined in the paper.  The new function prototypes are:

	struct callout_handle timeout(void (*func)(void *),
				      void *arg, int ticks);

	void untimeout(void (*func)(void *), void *arg,
		       struct callout_handle handle);

	If a client wishes to remove a timeout, it must store the
	callout_handle returned by timeout and pass it to untimeout.

	The new implementation gives 0(1) insert and removal of callouts
	making this interface scale well even for applications that
	keep 100s of callouts outstanding.

	See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Jordan K. Hubbard
1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00
David Greenman
3c4dd3568f Added $Id$ 1994-08-02 07:55:43 +00:00
Rodney W. Grimes
df8bae1de4 BSD 4.4 Lite Kernel Sources 1994-05-24 10:09:53 +00:00