From 92b4e9f11a636d1723cc0866bf8b9111b1e24339 Mon Sep 17 00:00:00 2001 From: Marta Rybczynska Date: Sun, 26 Jul 2020 20:54:40 +0200 Subject: 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 Signed-off-by: Peter Zijlstra (Intel) Acked-by: Will Deacon Link: https://lkml.kernel.org/r/CAApg2=SKxQ3Sqwj6TZnV-0x0cKLXFKDaPvXT4N15MPDMKq724g@mail.gmail.com --- Documentation/locking/locktypes.rst | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'Documentation/locking') diff --git a/Documentation/locking/locktypes.rst b/Documentation/locking/locktypes.rst index 4cefed8048ca..ddada4a53749 100644 --- a/Documentation/locking/locktypes.rst +++ b/Documentation/locking/locktypes.rst @@ -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() -- cgit v1.2.3