Interrupt queue, for managing a circular queue that both kernel
threads and interrupt handlers want to access. Used by the keyboard
and serial drivers.
+
+@item rtc.c
+@itemx rtc.h
+Real-time clock driver, to enable the kernel to determine the current
+date and time. By default, this is only used by @file{thread/init.c}
+to choose an initial seed for the random number generator.
@end table
@node lib files
@item random.c
@itemx random.h
-Pseudo-random number generator.
+Pseudo-random number generator. The actual sequence of random values
+will not vary from one Pintos run to another, unless you do one of
+three things: specify a new random seed value on the @option{-rs}
+kernel command-line option on each run, or use a simulator other than
+Bochs, or specify the @option{-r} option to @command{pintos}.
@item round.h
Macros for rounding.
who have done this have turned in code that did not even compile or
boot, much less pass any tests.
-Instead, we recommend integrating your team's changes early and often,
-using a source code control system such as CVS (@pxref{CVS}) or a
-group collaboration site such as SourceForge (@pxref{SourceForge}).
-This is less likely to produce surprises, because everyone can see
-everyone else's code as it is written, instead of just when it is
-finished. These systems also make it possible to review changes and,
-when a change introduces a bug, drop back to working versions of code.
+@localcvspolicy{}
You should expect to run into bugs that you simply don't understand
while working on this and subsequent projects. When you do,
nested priority donation, such as 8 levels.
You must implement priority donation for locks. You need not
-implement priority donation for semaphores or condition variables
-(but you are welcome to do so). You do need to implement
-priority scheduling in all cases.
+implement priority donation for the other Pintos synchronization
+constructs. You do need to implement priority scheduling in all
+cases.
Finally, implement the following functions that allow a thread to
examine and modify its own priority. Skeletons for these functions are
fact, @func{fail} called @func{debug_panic} (via the @func{PANIC}
macro). GCC knows that @func{debug_panic} does not return, because it
is declared @code{NO_RETURN} (@pxref{Function and Parameter
-Attributes}), so it doesn't include any code in @func{pass} to take
+Attributes}), so it doesn't include any code in @func{fail} to take
control when @func{debug_panic} returns. This means that the return
address on the stack looks like it is at the beginning of the function
that happens to follow @func{fail} in memory, which in this case happens
Don't worry about the possibility of timer values overflowing. Timer
values are expressed as signed 64-bit numbers, which at 100 ticks per
second should be good for almost 2,924,712,087 years. By then, we
-expect Pintos to have been phased out of the CS 140 curriculum.
+expect Pintos to have been phased out of the @value{coursenumber} curriculum.
@end table
@node Priority Scheduling FAQ