Commit graph

23 commits

Author SHA1 Message Date
rsc ef30c2c749 no more w 2007-08-20 18:55:51 +00:00
rsc 64659055bd ditto 2007-08-14 04:06:02 +00:00
rsc 3163085ace Cannot use "g" as an arg constraint because
some memory references aren't actually valid
and gcc is a bit too smart in parsing (%0) and
a bit too dumb in knowing which memory refs
are not valid.  Using "r" seems to constrain gcc
to use a register as in (%eax) and not substitute
a memory reference like (-36(%ebp)).

No one really understands these things.
2007-08-14 04:05:27 +00:00
rsc 31085bb416 more comments 2006-09-07 14:12:30 +00:00
rsc f552738889 no /* */ comments 2006-09-06 17:50:20 +00:00
rsc 9e9bcaf143 standardize various * conventions 2006-09-06 17:27:19 +00:00
rsc a650c606fe spacing fixes: no tabs, 2-space indents (for rtm) 2006-09-06 17:04:06 +00:00
kaashoek 7abf49d2f2 remove duplication
don't use the same name for two different pieces of code
2006-09-03 15:39:29 +00:00
rtm 2b19190c13 clean up stale error checks and panics
delete unused functions
a few comments
2006-08-29 14:45:45 +00:00
rtm 8a8be1b8c3 low-level keyboard input (not hooked up to /dev yet)
fix acquire() to cli() *before* incrementing nlock
make T_SYSCALL a trap gate, not an interrupt gate
sadly, various crashes if you hold down a keyboard key...
2006-08-10 02:07:10 +00:00
rtm 2927081628 uint32_t -> uint &c 2006-07-20 09:07:53 +00:00
rsc b5f17007f4 standarize on unix-like lowercase struct names 2006-07-17 01:58:13 +00:00
rsc ee9c7f3bfc goodbye PushRegs 2006-07-17 01:36:39 +00:00
rsc 564f787e91 Eliminate annoying Pseudodesc structure.
Eliminate unnecessary parts of mmu.h.
2006-07-16 16:55:52 +00:00
rsc ef2bd07ae4 standardize on not using foo_ prefix in struct foo 2006-07-16 15:41:47 +00:00
rsc 65bd8e139a New scheduler.
Removed cli and sti stack in favor of tracking
number of locks held on each CPU and explicit
conditionals in spinlock.c.
2006-07-16 01:15:28 +00:00
rtm 8148b6ee53 i think my cmpxchg use was wrong in acquire
nesting cli/sti: release shouldn't always enable interrupts
separate setup of lapic from starting of other cpus, so cpu() works earlier
flag to disable locking in console output
make locks work even when curproc==0
(still crashes in clock interrupt)
2006-07-12 11:15:38 +00:00
rsc 5ce9751cab Changes to allow use of native x86 ELF compilers, which on my
Linux 2.4 box using gcc 3.4.6 don't seem to follow the same
conventions as the i386-jos-elf-gcc compilers.
Can run make 'TOOLPREFIX=' or edit the Makefile.

curproc[cpu()] can now be NULL, indicating that no proc is running.
This seemed safer to me than having curproc[0] and curproc[1]
both pointing at proc[0] potentially.

The old implementation of swtch depended on the stack frame layout
used inside swtch being okay to return from on the other stack
(exactly the V6 you are not expected to understand this).
It also could be called in two contexts: at boot time, to schedule
the very first process, and later, on behalf of a process, to sleep
or schedule some other process.

I split this into two functions: scheduler and swtch.

The scheduler is now a separate never-returning function, invoked
by each cpu once set up.  The scheduler looks like:

	scheduler() {
		setjmp(cpu.context);

		pick proc to schedule
		blah blah blah

		longjmp(proc.context)
	}

The new swtch is intended to be called only when curproc[cpu()] is not NULL,
that is, only on behalf of a user proc.  It does:

	swtch() {
		if(setjmp(proc.context) == 0)
			longjmp(cpu.context)
	}

to save the current proc context and then jump over to the scheduler,
running on the cpu stack.

Similarly the system call stubs are now in assembly in usys.S to avoid
needing to know the details of stack frame layout used by the compiler.

Also various changes in the debugging prints.
2006-07-11 01:07:40 +00:00
kaashoek 7837c71b32 disable all interrupts when acquiring lock
user program that makes a blocking system call
2006-07-06 21:47:22 +00:00
kaashoek b22d898297 timer interrupts
disk interrupts (assuming bochs has a bug)
2006-07-05 20:00:14 +00:00
rtm 8b4e2a08fe swtch saves callee-saved registers
swtch idles on per-CPU stack, not on calling process's stack
fix pipe bugs
usertest.c tests pipes, fork, exit, close
2006-07-01 21:26:01 +00:00
kaashoek 21a88fd487 checkpoint. booting second processor. stack is messed up, but thanks to cliff
and plan 9 code, at least boots and gets into C code.
2006-06-22 01:28:57 +00:00
rtm 55e95b16db import 2006-06-12 15:22:12 +00:00