@item loader.S
@itemx loader.h
The kernel loader. Assembles to 512 bytes of code and data that the
-PC BIOS loads into memory and which in turn loads the kernel into
-memory, does basic processor initialization, and jumps to the
-beginning of the kernel. @xref{Pintos Loader}, for details. You should
-not need to look at this code or modify it.
+PC BIOS loads into memory and which in turn finds the kernel on disk,
+loads it into memory, and jumps to @func{start} in @file{start.S}.
+@xref{Pintos Loader}, for details. You should not need to look at
+this code or modify it.
+
+@item start.S
+Does basic setup needed for memory protection and 32-bit
+operation on 80@var{x}86 CPUs. Unlike the loader, this code is
+actually part of the kernel. @xref{Kernel Initialization},
+for details.
@item kernel.lds.S
The linker script used to link the kernel. Sets the load address of
-the kernel and arranges for @file{start.S} to be at the very beginning
+the kernel and arranges for @file{start.S} to be near the beginning
of the kernel image. @xref{Pintos Loader}, for details. Again, you
should not need to look at this code
or modify it, but it's here in case you're curious.
-@item start.S
-Jumps to @func{main}.
-
@item init.c
@itemx init.h
Kernel initialization, including @func{main}, the kernel's ``main
so you don't need to do so yourself.
It handles serial input by passing it to the input layer (see below).
-@item disk.c
-@itemx disk.h
-Supports reading and writing sectors on up to 4 IDE disks. This won't
-actually be used until project 2.
+@item block.c
+@itemx block.h
+An abstraction layer for @dfn{block devices}, that is, random-access,
+disk-like devices that are organized as arrays of fixed-size blocks.
+Out of the box, Pintos supports two types of block devices: IDE disks
+and partitions. Block devices, regardless of type, won't actually be
+used until project 2.
+
+@item ide.c
+@itemx ide.h
+Supports reading and writing sectors on up to 4 IDE disks.
+
+@item partition.c
+@itemx partition.h
+Understands the structure of partitions on disks, allowing a single
+disk to be carved up into multiple regions (partitions) for
+independent use.
@item kbd.c
@itemx kbd.h
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.
+
+@item speaker.c
+@itemx speaker.h
+Driver that can produce tones on the PC speaker.
+
+@item pit.c
+@itemx pit.h
+Code to configure the 8254 Programmable Interrupt Timer. This code is
+used by both @file{devices/timer.c} and @file{devices/speaker.c}
+because each devices uses one of the PIT's output channel.
@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
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
projects / pintos-anon / blobdiff