Re: [Qemu-devel] [RFC 01/10] target-arm: protect cpu_exclusive_*.

[Peter Maydell]

On 16 January 2015 at 17:19,  <address@hidden> wrote:
> From: KONRAD Frederic <address@hidden>
>
> This adds a lock to avoid multiple exclusive access at the same time in case 
> of
> TCG multithread.
>
> Signed-off-by: KONRAD Frederic <address@hidden>

All the same comments I had on this patch earlier still apply:

 * I think adding mutex handling code to all the target-*
   frontends rather than providing facilities in common
   code for them to use is the wrong approach
 * You will fail to unlock the mutex if the ldrex or strex
   takes a data abort
 * This is making no attempt to learn from or unify with
   the existing attempts at handling exclusives in linux-user.
   When we've done this work we should have a single
   mechanism for handling exclusives in a multithreaded
   host environment which is used by both softmmu and useronly
   configs

thanks
-- PMM