linux-stable.git/include/linux/mutex.h, branch v5.15.208 Linux kernel stable tree locking: Introduce __cleanup() based infrastructure 2025-10-19T14:21:51+00:00 Peter Zijlstra peterz@infradead.org 2025-10-15T15:05:54+00:00 f550466949e822afcd0b546a4fc35795930660bc [ Upstream commit 54da6a0924311c7cf5015533991e44fb8eb12773 ] Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 54da6a0924311c7cf5015533991e44fb8eb12773 ]

Use __attribute__((__cleanup__(func))) to build:

 - simple auto-release pointers using __free()

 - 'classes' with constructor and destructor semantics for
   scope-based resource management.

 - lock guards based on the above classes.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
locking/mutex: Introduce devm_mutex_init() 2024-07-18T11:07:26+00:00 George Stark gnstark@salutedevices.com 2024-04-11T16:10:25+00:00 e8053aa2ecc4784311cfdc971c4c58ea1d8edcab [ Upstream commit 4cd47222e435dec8e3787614924174f53fcfb5ae ] Using of devm API leads to a certain order of releasing resources. So all dependent resources which are not devm-wrapped should be deleted with respect to devm-release order. Mutex is one of such objects that often is bound to other resources and has no own devm wrapping. Since mutex_destroy() actually does nothing in non-debug builds frequently calling mutex_destroy() is just ignored which is safe for now but wrong formally and can lead to a problem if mutex_destroy() will be extended so introduce devm_mutex_init(). Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: George Stark <gnstark@salutedevices.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Marek Behún <kabel@kernel.org> Acked-by: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/r/20240411161032.609544-2-gnstark@salutedevices.com Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4cd47222e435dec8e3787614924174f53fcfb5ae ]

Using of devm API leads to a certain order of releasing resources.
So all dependent resources which are not devm-wrapped should be deleted
with respect to devm-release order. Mutex is one of such objects that
often is bound to other resources and has no own devm wrapping.
Since mutex_destroy() actually does nothing in non-debug builds
frequently calling mutex_destroy() is just ignored which is safe for now
but wrong formally and can lead to a problem if mutex_destroy() will be
extended so introduce devm_mutex_init().

Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: George Stark <gnstark@salutedevices.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20240411161032.609544-2-gnstark@salutedevices.com
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
locking/rtmutex: Add mutex variant for RT 2021-08-17T17:05:29+00:00 Thomas Gleixner tglx@linutronix.de 2021-08-15T21:29:01+00:00 bb630f9f7a7d43869e4e7f5e4c002207396aea59 Add the necessary defines, helpers and API functions for replacing struct mutex on a PREEMPT_RT enabled kernel with an rtmutex based variant. No functional change when CONFIG_PREEMPT_RT=n Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210815211305.081517417@linutronix.de 
Add the necessary defines, helpers and API functions for replacing struct mutex on
a PREEMPT_RT enabled kernel with an rtmutex based variant.

No functional change when CONFIG_PREEMPT_RT=n

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211305.081517417@linutronix.de
locking/mutex: Make mutex::wait_lock raw 2021-08-17T17:03:33+00:00 Thomas Gleixner tglx@linutronix.de 2021-08-15T21:28:36+00:00 ebf4c55c1ddbabaea120fe8d48ce25b4f5da93a1 The wait_lock of mutex is really a low level lock. Convert it to a raw_spinlock like the wait_lock of rtmutex. [ mingo: backmerged the test_lockup.c build fix by bigeasy. ] Co-developed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210815211304.166863404@linutronix.de 
The wait_lock of mutex is really a low level lock. Convert it to a
raw_spinlock like the wait_lock of rtmutex.

[ mingo: backmerged the test_lockup.c build fix by bigeasy. ]

Co-developed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211304.166863404@linutronix.de
locking/ww_mutex: Move the ww_mutex definitions from <linux/mutex.h> into <linux/ww_mutex.h> 2021-08-17T16:24:31+00:00 Thomas Gleixner tglx@linutronix.de 2021-08-15T21:28:34+00:00 4f1893ec8cfb4b17e3b89158a1e3e550a9a9bf3c Move the ww_mutex definitions into the ww_mutex specific header where they belong. Preparatory change to allow compiling ww_mutexes standalone. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210815211304.110216293@linutronix.de 
Move the ww_mutex definitions into the ww_mutex specific header where they
belong.

Preparatory change to allow compiling ww_mutexes standalone.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211304.110216293@linutronix.de
locking/mutex: Move the 'struct mutex_waiter' definition from <linux/mutex.h> to the internal header 2021-08-17T16:24:31+00:00 Thomas Gleixner tglx@linutronix.de 2021-08-15T21:28:33+00:00 43d2d52d704e025518d35c3079fcbff744623166 Move the mutex waiter declaration from the public <linux/mutex.h> header to the internal kernel/locking/mutex.h header. There is no reason to expose it outside of the core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210815211304.054325923@linutronix.de 
Move the mutex waiter declaration from the public <linux/mutex.h> header
to the internal kernel/locking/mutex.h header.

There is no reason to expose it outside of the core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211304.054325923@linutronix.de
Merge tag 'v5.12-rc5' into locking/core, to pick up fixes 2021-03-29T13:56:48+00:00 Ingo Molnar mingo@kernel.org 2021-03-29T13:56:48+00:00 feecb81732d8f271440d907beb082425e109f877 Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Signed-off-by: Ingo Molnar <mingo@kernel.org>
locking/mutex: Remove repeated declaration 2021-03-25T11:02:06+00:00 Shaokun Zhang zhangshaokun@hisilicon.com 2021-03-24T05:40:40+00:00 8af856d18bfbe89676ade38caa2a5d06f75f211d Commit 0cd39f4600ed ("locking/seqlock, headers: Untangle the spaghetti monster") introduces 'struct ww_acquire_ctx' again, remove the repeated declaration and move the pre-declarations to the top. Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/r/1616564440-61318-1-git-send-email-zhangshaokun@hisilicon.com 
Commit 0cd39f4600ed ("locking/seqlock, headers: Untangle the spaghetti monster")
introduces 'struct ww_acquire_ctx' again, remove the repeated declaration and move
the pre-declarations to the top.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/1616564440-61318-1-git-send-email-zhangshaokun@hisilicon.com
locking/mutex: Fix non debug version of mutex_lock_io_nested() 2021-03-23T11:20:23+00:00 Thomas Gleixner tglx@linutronix.de 2021-03-22T08:46:13+00:00 291da9d4a9eb3a1cb0610b7f4480f5b52b1825e7 If CONFIG_DEBUG_LOCK_ALLOC=n then mutex_lock_io_nested() maps to mutex_lock() which is clearly wrong because mutex_lock() lacks the io_schedule_prepare()/finish() invocations. Map it to mutex_lock_io(). Fixes: f21860bac05b ("locking/mutex, sched/wait: Fix the mutex_lock_io_nested() define") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/878s6fshii.fsf@nanos.tec.linutronix.de 
If CONFIG_DEBUG_LOCK_ALLOC=n then mutex_lock_io_nested() maps to
mutex_lock() which is clearly wrong because mutex_lock() lacks the
io_schedule_prepare()/finish() invocations.

Map it to mutex_lock_io().

Fixes: f21860bac05b ("locking/mutex, sched/wait: Fix the mutex_lock_io_nested() define")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/878s6fshii.fsf@nanos.tec.linutronix.de
locking/mutex: Kill mutex_trylock_recursive() 2021-02-10T13:44:40+00:00 Sebastian Andrzej Siewior bigeasy@linutronix.de 2021-02-10T08:52:47+00:00 0f319d49a4167e402b01b2b56639386f0b6846ba There are not users of mutex_trylock_recursive() in tree as of v5.11-rc7. Remove it. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210210085248.219210-2-bigeasy@linutronix.de 
There are not users of mutex_trylock_recursive() in tree as of
v5.11-rc7.

Remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210210085248.219210-2-bigeasy@linutronix.de