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authorRandy Dunlap <rdunlap@infradead.org>2020-03-25 17:58:14 +0100
committerThomas Gleixner <tglx@linutronix.de>2020-03-28 12:47:34 +0100
commit51e69e6551a8c6fffe0185ba305bb4e2d7223616 (patch)
tree21b8e5559dd7de05bb00a20d2ff824e49ea67204 /Documentation/locking
parentDocumentation/locking/locktypes: Further clarifications and wordsmithing (diff)
downloadlinux-51e69e6551a8c6fffe0185ba305bb4e2d7223616.tar.xz
linux-51e69e6551a8c6fffe0185ba305bb4e2d7223616.zip
Documentation/locking/locktypes: Minor copy editor fixes
Minor editorial fixes: - remove 'enabled' from PREEMPT_RT enabled kernels for consistency - add some periods for consistency - add "'" for possessive CPU's - spell out interrupts [ tglx: Picked up Paul's suggestions ] Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lkml.kernel.org/r/ac615f36-0b44-408d-aeab-d76e4241add4@infradead.org
Diffstat (limited to 'Documentation/locking')
-rw-r--r--Documentation/locking/locktypes.rst22
1 files changed, 11 insertions, 11 deletions
diff --git a/Documentation/locking/locktypes.rst b/Documentation/locking/locktypes.rst
index 1c18bb8785e2..09f45ce38d26 100644
--- a/Documentation/locking/locktypes.rst
+++ b/Documentation/locking/locktypes.rst
@@ -84,7 +84,7 @@ rtmutex
RT-mutexes are mutexes with support for priority inheritance (PI).
-PI has limitations on non PREEMPT_RT enabled kernels due to preemption and
+PI has limitations on non-PREEMPT_RT kernels due to preemption and
interrupt disabled sections.
PI clearly cannot preempt preemption-disabled or interrupt-disabled
@@ -150,7 +150,7 @@ kernel configuration including PREEMPT_RT enabled kernels.
raw_spinlock_t is a strict spinning lock implementation in all kernels,
including PREEMPT_RT kernels. Use raw_spinlock_t only in real critical
-core code, low level interrupt handling and places where disabling
+core code, low-level interrupt handling and places where disabling
preemption or interrupts is required, for example, to safely access
hardware state. raw_spinlock_t can sometimes also be used when the
critical section is tiny, thus avoiding RT-mutex overhead.
@@ -160,20 +160,20 @@ spinlock_t
The semantics of spinlock_t change with the state of PREEMPT_RT.
-On a non PREEMPT_RT enabled kernel spinlock_t is mapped to raw_spinlock_t
-and has exactly the same semantics.
+On a non-PREEMPT_RT kernel spinlock_t is mapped to raw_spinlock_t and has
+exactly the same semantics.
spinlock_t and PREEMPT_RT
-------------------------
-On a PREEMPT_RT enabled kernel spinlock_t is mapped to a separate
-implementation based on rt_mutex which changes the semantics:
+On a PREEMPT_RT kernel spinlock_t is mapped to a separate implementation
+based on rt_mutex which changes the semantics:
- - Preemption is not disabled
+ - Preemption is not disabled.
- The hard interrupt related suffixes for spin_lock / spin_unlock
- operations (_irq, _irqsave / _irqrestore) do not affect the CPUs
- interrupt disabled state
+ operations (_irq, _irqsave / _irqrestore) do not affect the CPU's
+ interrupt disabled state.
- The soft interrupt related suffix (_bh()) still disables softirq
handlers.
@@ -279,8 +279,8 @@ fully preemptible context. Instead, use spin_lock_irq() or
spin_lock_irqsave() and their unlock counterparts. In cases where the
interrupt disabling and locking must remain separate, PREEMPT_RT offers a
local_lock mechanism. Acquiring the local_lock pins the task to a CPU,
-allowing things like per-CPU irq-disabled locks to be acquired. However,
-this approach should be used only where absolutely necessary.
+allowing things like per-CPU interrupt disabled locks to be acquired.
+However, this approach should be used only where absolutely necessary.
raw_spinlock_t