lkml.org 
[lkml]   [2007]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 00/12] Syslets, Threadlets, generic AIO support, v5

Hi Ingo,

> this is the v5 release of the syslet/threadlet subsystem:
>
> http://redhat.com/~mingo/syslet-patches/

Nice!

I tried to port this to ppc64 but found a few problems:

The 64bit powerpc ABI has the concept of a TOC (r2) which is used for
per function data. This means this wont work:

if (ah->restore_stack) {
set_task_stack_reg(new_task, ah->restore_stack);
task_ip_reg(new_task) = ah->restore_ip;
/*
* The return code 0 is needed to tell the
* head user-context that the threadlet went async:
*/
task_ret_reg(new_task) = 0;
}

I think we would want to change restore_ip to restore_function, and then
create a per arch helper, perhaps:

void set_user_context(struct task_struct *task, unsigned long stack,
unsigned long function, unsigned long retval);

ppc64 could then grab the ip and r2 values from the function descriptor.

The other issue involves the syscall table:

asmlinkage struct syslet_uatom __user *
sys_async_exec(struct syslet_uatom __user *uatom,
struct async_head_user __user *ahu)
{
return __sys_async_exec(uatom, ahu, sys_call_table, NR_syscalls);
}

This exposes the layout of the syscall table. Unfortunately it wont work
on ppc64. In arch/powerpc/kernel/systbl.S:

#define COMPAT_SYS(func) .llong .sys_##func,.compat_sys_##func

Both syscall tables are overlaid.

Anton
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-03-07 21:16    [W:0.063 / U:0.392 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site