bootblocks, the kernel shows up as the primary module:
[3:24am]~-100# kldstat
Id Refs Address Size Name
1 1 0xf0100000 ff00000 /kernel
^^^^ oops.. :-)
Based heavily on aout_freebsd.c. Hmm.. There's so much in common that
these could probably be combined and just check the metadata to see which
format it is.
so far, and should probably be able to be made to work for the alpha
without too much trouble once it's connected up and my assumptions tested.
I think (but have not tested) it will also load "old" ELF kernels that
were not linked with DYNAMIC headers.
The module glue is yet to come. (oh fun.. :-)
It does not explicitly load symbols [yet]. The _DYNAMIC data contains a
runtime symbol set that ddb can use via ddb/db_kld.c. It'll be missing
some detail that stabs normally provides (eg: number of args to a function,
line numbers, etc). On the other hand, those minimal symbols will always
be available even on a stripped kernel.
This is mostly stolen from load_aout.c with some ideas from
alpha/libalpha/elf_freebsd.c.
the in-kernel linker to access the _DYNAMIC data for doing loadable elf
modules. The alpha kernel is already done this way, I've borrowed some of
the hacks from there.
This is primarily aimed at the 3-stage boot process which is intended to
be able to do pre-loading of kernel modules.
Note that the entry point isn't 0xf0100000 any more, it'll be a little
further on - but this value is stored in the headers. I don't think this
will be a problem, but I'm sure somebody will tell me if it is. :-)
I'm not sure if btxboot is going to like this, it doesn't do proper ELF
header checking and assumes that there are exactly two program header
entries and that they are both PT_LOAD entries - a bad assumption.
the thread kernel into a garbage collector thread which is started when
the fisrt thread is created (other than the initial thread). This
removes the window of opportunity where a context switch will cause a
thread that has locked the malloc spinlock, to enter the thread kernel,
find there is a dead thread and try to free memory, therefore trying
to lock the malloc spinlock against itself.
The garbage collector thread acts just like any other thread, so
instead of having a spinlock to control accesses to the dead thread
list, it uses a mutex and a condition variable so that it can happily
wait to be signalled when a thread exists.
launching an application into space when someone tries to debug it.
The dead thread list now has it's own link pointer, so use that when
reporting the grateful dead.
- Add support of a thread being listed in the dead thread list as well
as the thread list.
- Add a new thread state to make sigwait work properly. (Submitted by
Daniel M. Eischen <eischen@vigrid.com>)
- Add global variable for the garbage collector mutex and condition
variable.
- Delete a couple of prototypes that are no longer required.
- Add a prototype for the garbage collector thread.
realloc functions check for recursion within the malloc code itself. In
a thread-safe library, the single spinlock ensures that no two threads
go inside the protected code at the same time. The thread implementation
is responsible for ensuring that the spinlock does in fact protect malloc.
There was a window of opportunity in which this was not the case. I'll fix
that with a commit RSN.
