Use sx locks rather than lockmgr locks for eventhandlers.

Submitted by: Jonathan Mini <mini@haikugeek.com>

Remove __P

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is fu

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

show more ...

Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys

Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.

Sort sys/*.h includes where possible in affected files.

OK'ed by: bde (with reservations)

show more ...

- Convert the per-eventhandler list mutex to a lockmgr lock so that it can
be safely held across an eventhandler function call.
- Fix an instance of the head of an eventhandler list being read with

- Convert the per-eventhandler list mutex to a lockmgr lock so that it can
be safely held across an eventhandler function call.
- Fix an instance of the head of an eventhandler list being read without
the lock being held.
- Break down and use a SYSINIT at the new SI_SUB_EVENTHANDLER to initialize
the eventhandler global mutex and the eventhandler list of lists rather
than using a non-MP safe initialization during the first call to
eventhandler_register().
- Add in a KASSERT() to eventhandler_register() to ensure that we don't try
to register an eventhandler before things have been initialized.

show more ...

Only hold the mutex for an eventhandler list while the list is being accessed.
Specifically, don't hold the lock while calling event handlers as a handler
may tsleep() while holding the mutex.

Found

Only hold the mutex for an eventhandler list while the list is being accessed.
Specifically, don't hold the lock while calling event handlers as a handler
may tsleep() while holding the mutex.

Found by: witness

show more ...

- Make the eventhandler_mutex mutex a private variable in
subr_eventhandler.c
- Move the extra #include's in sys/eventhandler.h to be protected by
the #ifndef SYS_EVENTHANDLER/#endif

Catch up to moving headers:
- machine/ipl.h -> sys/ipl.h
- machine/mutex.h -> sys/mutex.h

Change the way that eventhandler lists are processed so that an event
handler can safely remove itself from a list while being run.

(Note that it is not safe to remove anything else from the same li

Change the way that eventhandler lists are processed so that an event
handler can safely remove itself from a list while being run.

(Note that it is not safe to remove anything else from the same list,
as this may still cause corruption in the case where the removed
item is next on the list.)

show more ...

Fix EVENTHANDLER_FAST_DEREGISTER

Don't include proc.h now that mutex.h does it for us.

Make the EVENTHANDLER mechanism MP-safe. Events can now be invoked
without holding the Giant lock.

Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by: msmith and others

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

Fixed pedantic syntax errors caused by a trailing semicolon in the
definition of EVENTHANDLER_DECLARE().

Removed all other trailing semicolons in macro definitions. The
ones after `do ... while (0)

Fixed pedantic syntax errors caused by a trailing semicolon in the
definition of EVENTHANDLER_DECLARE().

Removed all other trailing semicolons in macro definitions. The
ones after `do ... while (0)' wrappers defeated the point of the
wrappers but were harmless.

Enforce semicolons after invocation of declaration-like macros.

show more ...

Remove the unused 'func' arguments to the deregistration functions.

Submitted by: Darrell Anderson <anderson@cs.duke.edu>

$Id$ -> $FreeBSD$

Add a missing underscore that made EVENTHANDLER_FAST_INVOKE broken.

Implement a new generic mechanism for attaching handler functions to
events, in order to pave the way for removing a number of the ad-hoc
implementations currently in use.

Retire the at_shutdown fam

Implement a new generic mechanism for attaching handler functions to
events, in order to pave the way for removing a number of the ad-hoc
implementations currently in use.

Retire the at_shutdown family of functions and replace them with
new event handler lists.

Rework kern_shutdown.c to take greater advantage of the use of event
handlers.

Reviewed by: green

show more ...

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

show more ...

kern_reboot(9): describe event handlers

Add more details about the execution and purpose of these shutdown
handlers. Make a point to mention the requirement that they can be run
in a normal or panic

kern_reboot(9): describe event handlers

Add more details about the execution and purpose of these shutdown
handlers. Make a point to mention the requirement that they can be run
in a normal or panic context. Add some simple examples.

Add a brief comment to the declaration in sys/eventhandler.h.

Reviewed by: markj
Discussed with: rpokala, Pau Amma <pauamma@gundo.com>
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39135

show more ...

protosw: retire pr_drain and use EVENTHANDLER(9) directly

The method was called for two different conditions: 1) the VM layer is
low on pages or 2) one of UMA zones of mbuf allocator exhausted.
This

protosw: retire pr_drain and use EVENTHANDLER(9) directly

The method was called for two different conditions: 1) the VM layer is
low on pages or 2) one of UMA zones of mbuf allocator exhausted.
This change 2) into a new event handler, but all affected network
subsystems modified to subscribe to both, so this change shall not
bring functional changes under different low memory situations.

There were three subsystems still using pr_drain: TCP, SCTP and frag6.
The latter had its protosw entry for the only reason to register its
pr_drain method.

Reviewed by: tuexen, melifaro
Differential revision: https://reviews.freebsd.org/D36164

show more ...

devd: move all devd notification logic to a separate file.

Currently, subr_bus.c shares logic for (a) maintaining all HW devices
(e.g. discovery/attach/detach logic) and (b) generic devctl notifica

devd: move all devd notification logic to a separate file.

Currently, subr_bus.c shares logic for (a) maintaining all HW devices
(e.g. discovery/attach/detach logic) and (b) generic devctl notification
layer for devices/PMU/GEOM/interfaces/etc).
These two subsystems share really tiny interaction interface, composed of 3
notification functions. With that in mind, move devctl layer to a
separate file, establishing a clear notification interface between the
sub.c bus layer and the provider (devctl).

The primary driver of this change is netlink implementation (D36002).
The idea is to propagate device-level events to netlink as well, so all
netlink customers can subscribe to these changes.
The long-term goal is to deprecate devctl and to use netlink as the
kernel<> userland transport provided netlink gets enough traction.

Reviewed by: imp, markj
Differential Revision: https://reviews.freebsd.org/D36091
MFC after: 1 month

show more ...

eventhandler: Remove a double world in two comments

- s/be be/be/

MFC after: 3 days

Minor style cleanup

We prefer 'while (0)' to 'while(0)' according to grep and stlye(9)'s
space after keyword rule. Remove a few stragglers of the latter.
Many of these usages were inconsistent withi

Minor style cleanup

We prefer 'while (0)' to 'while(0)' according to grep and stlye(9)'s
space after keyword rule. Remove a few stragglers of the latter.
Many of these usages were inconsistent within the file.

MFC After: 3 days
Sponsored by: Netflix

show more ...