The title of this paper is an homage to David Goldberg’s classic paper “What Every Computer Scientist Should Know About Floating-Point Arithmetic” [goldberg]. Goldberg’s paper is still not widely known, although it should be a prerequisite for anybody daring to touch a keyboard for serious programming.
Read What every programmer should know about memory - […]
Tags: Electronics · Kernel
In the 2.4 series kernels, the handle_scancode function was used to transmit scancodes to the tty layer. The 2.6 kernels don’t seem to have this function - but mysteriously, even though the definition of this function is nowhere to be seen, its being called from a few places. Maybe, this code is never getting […]
Tags: Kernel
The Linux kernel developers have come out with some kind of `position statement’ on the GPLv3:
The Dangers and problems with GPLv3
It’s unlikely that people like Andrew Morton (and for that matter, Linus) don’t understand the dangers of Tivoization. Then why spread FUD about the GPLv3?
Shashank Sharma has written a very readable article on […]
Tags: Free Software · Kernel
Greg Kroah-Hartman has written a document for people interested in getting involved with kernel development:
Read Greg K-H’s HOWTO do Linux kernel development
Tags: Kernel
It’s great if students are exposed to professional, high quality code early in their engineering education. The difficulty is in identifying code which challenges the newbie student intellectually but doesn’t fly far above his head. I am trying to build a small collection of code snippets taken from real programs which demonstrates the subtleties […]
Tags: Favourite · Kernel · Programming
Faster system calls
The classical Linux system call mechanism is to put the
call number in the eax register (in the case of i386) and
simply invoke:
int $0×80
Here is a code fragment which measures the time taken to
invoke `getpid’ 10000000 times:
#define N 10000000
int pid;
main()
{
int i;
for(i = 0; i < N; i++) {
asm(”movl $20, %%eax \n”
[…]