linux.git/kernel/notifier.c, branch v6.18.21

reboot: move reboot_notifier_list to kernel/reboot.c

2024-11-06T01:12:31+00:00

All the functions related to the reboot notifier list are in
kernel/reboot.c.  Move the list itself, too.  As there are no direct users
anymore, make the declaration static.

Link: https://lkml.kernel.org/r/20241012-reboot_notifier_list-v1-1-6093bb9455ce@weissschuh.net
Signed-off-by: Thomas Weißschuh 
Cc: Greg Kroah-Hartman 
Signed-off-by: Andrew Morton

notifiers: add tracepoints to the notifiers infrastructure

2023-04-08T20:45:38+00:00

Currently there is no way to show the callback names for registered,
unregistered or executed notifiers. This is very useful for debug
purposes, hence add this functionality here in the form of notifiers'
tracepoints, one per operation.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20230314200058.1326909-1-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli 
Cc: Arjan van de Ven 
Cc: Michael Kelley 
Cc: Steven Rostedt 
Cc: Xiaoming Ni 
Cc: Baoquan He 
Cc: Cong Wang 
Cc: Dmitry Osipenko 
Cc: Guilherme G. Piccoli 
Cc: Guilherme G. Piccoli 
Cc: Petr Mladek 
Cc: Rafael J. Wysocki 
Cc: Sebastian Andrzej Siewior 
Cc: Valentin Schneider 
Signed-off-by: Andrew Morton

kernel/notifier: Remove CONFIG_SRCU

2023-02-03T00:26:06+00:00

Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in conditional compilation based on CONFIG_SRCU.
Therefore, remove the #ifdef.

Signed-off-by: Paul E. McKenney 
Cc: "Rafael J. Wysocki" 
Cc: "Michał Mirosław" 
Cc: Borislav Petkov 
Cc: Alan Stern 
Acked-by: Rafael J. Wysocki 
Reviewed-by: John Ogness

notifier: repair slips in kernel-doc comments

2022-11-30T18:32:30+00:00

Invoking ./scripts/kernel-doc -none kernel/notifier.c warns:

  kernel/notifier.c:71: warning: Excess function parameter 'returns' description in 'notifier_call_chain'
  kernel/notifier.c:119: warning: Function parameter or member 'v' not described in 'notifier_call_chain_robust'

These two warning are easy to fix, as they are just due to some minor slips
that makes the comment not follow kernel-doc's syntactic expectation.

Fix those minor slips in kernel-doc comments for make W=1 happiness.

Signed-off-by: Lukas Bulwahn 
Signed-off-by: Rafael J. Wysocki

notifier: Add blocking/atomic_notifier_chain_register_unique_prio()

2022-05-19T17:30:30+00:00

Add variant of blocking/atomic_notifier_chain_register() functions that
allow registration of a notifier only if it has unique priority, otherwise
-EBUSY error code is returned by the new functions.

Reviewed-by: Michał Mirosław 
Signed-off-by: Dmitry Osipenko 
Signed-off-by: Rafael J. Wysocki

notifier: Add atomic_notifier_call_chain_is_empty()

2022-05-19T17:25:06+00:00

Add atomic_notifier_call_chain_is_empty() that returns true if given
atomic call chain is empty.

The first user of this new notifier API function will be the kernel
power-off core code that will support power-off call chains. The core
code will need to check whether there is a power-off handler registered
at all in order to decide whether to halt machine or power it off.

Reviewed-by: Michał Mirosław 
Signed-off-by: Dmitry Osipenko 
Signed-off-by: Rafael J. Wysocki

notifier: Return an error when a callback has already been registered

2021-12-29T09:37:33+00:00

Return -EEXIST when a notifier callback has already been registered on a
notifier chain.

This should avoid any homegrown registration tracking at the callsite
like

  https://lore.kernel.org/amd-gfx/20210512013058.6827-1-mukul.joshi@amd.com

for example.

This version is an alternative of

  https://lore.kernel.org/r/20211108101157.15189-1-bp@alien8.de

which needed to touch every caller not checking the registration
routine's return value.

Signed-off-by: Borislav Petkov 
Reviewed-by: Sebastian Andrzej Siewior 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/YcSWNdUBS8A2ZB3s@zn.tnic

notifier: Remove atomic_notifier_call_chain_robust()

2021-08-16T16:55:32+00:00

This now has no more users, remove it.

Suggested-by: Sebastian Andrzej Siewior 
Signed-off-by: Valentin Schneider 
Acked-by: Sebastian Andrzej Siewior 
Signed-off-by: Rafael J. Wysocki

notifier: Fix broken error handling pattern

2020-09-01T07:58:03+00:00

The current notifiers have the following error handling pattern all
over the place:

	int err, nr;

	err = __foo_notifier_call_chain(&chain, val_up, v, -1, &nr);
	if (err & NOTIFIER_STOP_MASK)
		__foo_notifier_call_chain(&chain, val_down, v, nr-1, NULL)

And aside from the endless repetition thereof, it is broken. Consider
blocking notifiers; both calls take and drop the rwsem, this means
that the notifier list can change in between the two calls, making @nr
meaningless.

Fix this by replacing all the __foo_notifier_call_chain() functions
with foo_notifier_call_chain_robust() that embeds the above pattern,
but ensures it is inside a single lock region.

Note: I switched atomic_notifier_call_chain_robust() to use
      the spinlock, since RCU cannot provide the guarantee
      required for the recovery.

Note: software_resume() error handling was broken afaict.

Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Ingo Molnar 
Acked-by: Rafael J. Wysocki 
Link: https://lore.kernel.org/r/20200818135804.325626653@infradead.org

mm: remove vmalloc_sync_(un)mappings()

2020-06-02T17:59:12+00:00

These functions are not needed anymore because the vmalloc and ioremap
mappings are now synchronized when they are created or torn down.

Remove all callers and function definitions.

Signed-off-by: Joerg Roedel 
Signed-off-by: Andrew Morton 
Tested-by: Steven Rostedt (VMware) 
Acked-by: Andy Lutomirski 
Acked-by: Peter Zijlstra (Intel) 
Cc: Arnd Bergmann 
Cc: Christoph Hellwig 
Cc: Dave Hansen 
Cc: "H . Peter Anvin" 
Cc: Ingo Molnar 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: "Rafael J. Wysocki" 
Cc: Thomas Gleixner 
Cc: Vlastimil Babka 
Link: http://lkml.kernel.org/r/20200515140023.25469-7-joro@8bytes.org
Signed-off-by: Linus Torvalds