Re: generic rwsem [Re: Alpha "process table hang"]

[David Howells <dhowells@cambridge.redhat.com>]

Andrea,

How did you generate the 00_rwsem-generic-1 patch? Against what did you diff?
You seem to have removed all the optimised i386 rwsem stuff... Did it not work
for you?

> (the generic rwsemaphores in those kernels is broken, try to use them in
> other archs or x86 and you will notice) and I cannot reproduce the hang any
> longer.

Can you supply a test case that demonstrates it not working?

> My generic rwsem should be also cleaner and faster than the generic ones in
> 2.4.4pre3 and they can be turned off completly so an architecture can really
> takeover with its own asm implementation.

I quick look says it shouldn't be faster (inline functions and all that).

However, I think you might be right about it being too dependent on the
algorithm I put in, and that is easy to change.

> (while with the 2.4.4pre3 design this is obviously not possible because
> lib/rwsem.c compilation isn't conditional and such file knows the internals
> of the struct rw_semaphore).

Could be very easily changed.

David