From 36771800f7bfa985736db684d0c820c96db887ae Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Tue, 14 Dec 2004 18:13:34 +0000 Subject: [PATCH] Wording improvements. --- doc/tour.texi | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/doc/tour.texi b/doc/tour.texi index e9ba008..ed1f92b 100644 --- a/doc/tour.texi +++ b/doc/tour.texi @@ -495,7 +495,7 @@ is, kernel threads can be preempted at any time. Traditional Unix systems are ``nonpreemptible,'' that is, kernel threads can only be preempted at points where they explicitly call into the scheduler. User programs can be preempted at any time in both models. As you -might imagine, preemptible kernels require more use of +might imagine, preemptible kernels require more explicit synchronization. You should have little need to set the interrupt state directly. Most @@ -530,8 +530,8 @@ Turns interrupts off and returns the previous interrupt state. @node Semaphores @subsubsection Semaphores -A semaphore is a nonnegative integer along with two atomic operators -for manipulating it, which are: +A semaphore is a nonnegative integer along with two operators +for atomically manipulating it, which are: @itemize @bullet @item @@ -594,7 +594,7 @@ semaphore is twofold. First, a semaphore can have a value greater than 1, but a lock can only be owned by a single thread at a time. Second, a semaphore does not have an owner, meaning that one thread can ``down'' the semaphore and then another one ``up'' it, but with a -lock the same thread must both acquire and release it. When these +lock a single thread must both acquire and release it. When these restrictions prove onerous, it's a good sign that a semaphore should be used, instead of a lock. @@ -633,8 +633,8 @@ A condition variable allows one piece of code to signal a condition and cooperating code to receive the signal and act upon it. Each condition variable is associated with a lock. A given condition variable is associated with only a single lock, but one lock may be -associated with any number of condition variables. A lock along with -all of its condition variables is known as a ``monitor.'' +associated with any number of condition variables. A set of condition +variables taken together with their lock is called a ``monitor.'' A thread that owns the monitor lock is said to be ``in the monitor.'' The thread in the monitor has control over all the data protected with @@ -736,7 +736,7 @@ timer, keyboard, serial ports, and disks. External interrupts are @dfn{asynchronous}, meaning that they don't occur in a fashion synchronized with anything going on in the CPU. External interrupts are what @func{intr_disable} and related functions can arrange to -temporarily ignore (@pxref{Disabling Interrupts}). +postpone (@pxref{Disabling Interrupts}). @item @dfn{Internal interrupts}, that is, interrupts caused by something -- 2.30.2