user/sven/linux.git/include/linux/mutex.h, branch v6.0.9

locking/rtmutex: Add mutex variant for RT

2021-08-17T17:05:29Z

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 Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211305.081517417@linutronix.de

locking/mutex: Make mutex::wait_lock raw

2021-08-17T17:03:33Z

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 Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211304.166863404@linutronix.de

locking/ww_mutex: Move the ww_mutex definitions from into

2021-08-17T16:24:31Z

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 Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211304.110216293@linutronix.de

locking/mutex: Move the 'struct mutex_waiter' definition from to the internal header

2021-08-17T16:24:31Z

Move the mutex waiter declaration from the public 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 Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211304.054325923@linutronix.de

Merge tag 'v5.12-rc5' into locking/core, to pick up fixes

2021-03-29T13:56:48Z

Signed-off-by: Ingo Molnar

locking/mutex: Remove repeated declaration

2021-03-25T11:02:06Z

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 Signed-off-by: Ingo Molnar Acked-by: Waiman Long 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()

2021-03-23T11:20:23Z

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 Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/878s6fshii.fsf@nanos.tec.linutronix.de

locking/mutex: Kill mutex_trylock_recursive()

2021-02-10T13:44:40Z

There are not users of mutex_trylock_recursive() in tree as of v5.11-rc7. Remove it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20210210085248.219210-2-bigeasy@linutronix.de

locking/seqlock, headers: Untangle the spaghetti monster

2020-08-06T14:13:13Z

By using lockdep_assert_*() from seqlock.h, the spaghetti monster attacked. Attack back by reducing seqlock.h dependencies from two key high level headers: - : -Remove - : -Remove - : +Add The price was to add it to sched.h ... Core header fallout, we add direct header dependencies instead of gaining them parasitically from higher level headers: - : +Add - : +Add - : +Add - : +Add - : +Add - : +Add Arch headers fallout: - PARISC: : +Add - SH: : +Add - SPARC: : +Add - SPARC: : +Add , -Remove - X86: : +Add -Remove There's also a bunch of parasitic header dependency fallout in .c files, not listed separately. [ mingo: Extended the changelog, split up & fixed the original patch. ] Co-developed-by: Ingo Molnar Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net

lockdep: Introduce wait-type checks

2020-03-21T15:00:24Z

Extend lockdep to validate lock wait-type context. The current wait-types are: LD_WAIT_FREE, /* wait free, rcu etc.. */ LD_WAIT_SPIN, /* spin loops, raw_spinlock_t etc.. */ LD_WAIT_CONFIG, /* CONFIG_PREEMPT_LOCK, spinlock_t etc.. */ LD_WAIT_SLEEP, /* sleeping locks, mutex_t etc.. */ Where lockdep validates that the current lock (the one being acquired) fits in the current wait-context (as generated by the held stack). This ensures that there is no attempt to acquire mutexes while holding spinlocks, to acquire spinlocks while holding raw_spinlocks and so on. In other words, its a more fancy might_sleep(). Obviously RCU made the entire ordeal more complex than a simple single value test because RCU can be acquired in (pretty much) any context and while it presents a context to nested locks it is not the same as it got acquired in. Therefore its necessary to split the wait_type into two values, one representing the acquire (outer) and one representing the nested context (inner). For most 'normal' locks these two are the same. [ To make static initialization easier we have the rule that: .outer == INV means .outer == .inner; because INV == 0. ] It further means that its required to find the minimal .inner of the held stack to compare against the outer of the new lock; because while 'normal' RCU presents a CONFIG type to nested locks, if it is taken while already holding a SPIN type it obviously doesn't relax the rules. Below is an example output generated by the trivial test code: raw_spin_lock(&foo); spin_lock(&bar); spin_unlock(&bar); raw_spin_unlock(&foo); [ BUG: Invalid wait context ] ----------------------------- swapper/0/1 is trying to lock: ffffc90000013f20 (&bar){....}-{3:3}, at: kernel_init+0xdb/0x187 other info that might help us debug this: 1 lock held by swapper/0/1: #0: ffffc90000013ee0 (&foo){+.+.}-{2:2}, at: kernel_init+0xd1/0x187 The way to read it is to look at the new -{n,m} part in the lock description; -{3:3} for the attempted lock, and try and match that up to the held locks, which in this case is the one: -{2,2}. This tells that the acquiring lock requires a more relaxed environment than presented by the lock stack. Currently only the normal locks and RCU are converted, the rest of the lockdep users defaults to .inner = INV which is ignored. More conversions can be done when desired. The check for spinlock_t nesting is not enabled by default. It's a separate config option for now as there are known problems which are currently addressed. The config option allows to identify these problems and to verify that the solutions found are indeed solving them. The config switch will be removed and the checks will permanently enabled once the vast majority of issues has been addressed. [ bigeasy: Move LD_WAIT_FREE,… out of CONFIG_LOCKDEP to avoid compile failure with CONFIG_DEBUG_SPINLOCK + !CONFIG_LOCKDEP] [ tglx: Add the config option ] Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200321113242.427089655@linutronix.de