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Code Issues Releases Wiki Activity

Documentation/locking/locktypes: Fix local_locks documentation 

Fix issues with local_locks documentation:

 - fix function names, local_lock.h has local_unlock_irqrestore(), not
   local_lock_irqrestore()

 - fix mapping table, local_unlock_irqrestore() maps to
   local_irq_restore(), not _save()

Signed-off-by: Marta Rybczynska <rybczynska@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CAApg2=SKxQ3Sqwj6TZnV-0x0cKLXFKDaPvXT4N15MPDMKq724g@mail.gmail.com
This commit is contained in:
Marta Rybczynska 2020-07-26 20:54:40 +02:00 committed by Peter Zijlstra
parent a28e884b96
commit 92b4e9f11a
1 changed files with 12 additions and 12 deletions
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24
Documentation/locking/locktypes.rst
View File

@ -164,14 +164,14 @@ by disabling preemption or interrupts.
On non-PREEMPT_RT kernels local_lock operations map to the preemption and
interrupt disabling and enabling primitives:
=========================== ======================
local_lock(&llock) preempt_disable()
local_unlock(&llock) preempt_enable()
local_lock_irq(&llock) local_irq_disable()
local_unlock_irq(&llock) local_irq_enable()
local_lock_save(&llock) local_irq_save()
local_lock_restore(&llock) local_irq_save()
=========================== ======================
=============================== ======================
local_lock(&llock) preempt_disable()
local_unlock(&llock) preempt_enable()
local_lock_irq(&llock) local_irq_disable()
local_unlock_irq(&llock) local_irq_enable()
local_lock_irqsave(&llock) local_irq_save()
local_unlock_irqrestore(&llock) local_irq_restore()
=============================== ======================
The named scope of local_lock has two advantages over the regular
primitives:
@ -353,14 +353,14 @@ protection scope. So the following substitution is wrong::
{
local_irq_save(flags); -> local_lock_irqsave(&local_lock_1, flags);
func3();
local_irq_restore(flags); -> local_lock_irqrestore(&local_lock_1, flags);
local_irq_restore(flags); -> local_unlock_irqrestore(&local_lock_1, flags);
}
func2()
{
local_irq_save(flags); -> local_lock_irqsave(&local_lock_2, flags);
func3();
local_irq_restore(flags); -> local_lock_irqrestore(&local_lock_2, flags);
local_irq_restore(flags); -> local_unlock_irqrestore(&local_lock_2, flags);
}
func3()
@ -379,14 +379,14 @@ PREEMPT_RT-specific semantics of spinlock_t. The correct substitution is::
{
local_irq_save(flags); -> local_lock_irqsave(&local_lock, flags);
func3();
local_irq_restore(flags); -> local_lock_irqrestore(&local_lock, flags);
local_irq_restore(flags); -> local_unlock_irqrestore(&local_lock, flags);
}
func2()
{
local_irq_save(flags); -> local_lock_irqsave(&local_lock, flags);
func3();
local_irq_restore(flags); -> local_lock_irqrestore(&local_lock, flags);
local_irq_restore(flags); -> local_unlock_irqrestore(&local_lock, flags);
}
func3()