Use macros for 8259A PIC registers, instead of writing them literally.

[pintos-anon] / doc / 44bsd.texi

diff --git a/doc/44bsd.texi b/doc/44bsd.texi
index d27343f655d979540f74b1243fcffb4000e6bbe8..f1638f80d31daae0739a263d7e5ddaa02583a2b7 100644 (file)
--- a/doc/44bsd.texi
+++ b/doc/44bsd.texi
@@ -113,7 +113,9 @@ the formula
 
 @noindent where @var{recent_cpu} is an estimate of the CPU time the
 thread has used recently (see below) and @var{nice} is the thread's
-@var{nice} value.  The coefficients @math{1/4} and 2 on @var{recent_cpu}
+@var{nice} value.  The result should be rounded down to the nearest
+integer (truncated).
+The coefficients @math{1/4} and 2 on @var{recent_cpu}
 and @var{nice}, respectively, have been found to work well in practice
 but lack deeper meaning.  The calculated @var{priority} is always
 adjusted to lie in the valid range @code{PRI_MIN} to @code{PRI_MAX}.
@@ -182,7 +184,7 @@ current value of @var{recent_cpu} decays to a weight of .1 in
 received ``recently,'' with the rate of decay inversely proportional to
 the number of threads competing for the CPU.
 
-Assumptions made by some of the tests require that updates to
+Assumptions made by some of the tests require that these recalculations of
 @var{recent_cpu} be made exactly when the system tick counter reaches a
 multiple of a second, that is, when @code{timer_ticks () % TIMER_FREQ ==
 0}, and not at any other time.