Re: [Qemu-devel] [RFC 1/5] exec: Add new exclusive bitmap to ram_list

[Richard Henderson <rth@twiddle.net>]

On 05/06/2015 08:38 AM, Alvise Rigo wrote:
> The purpose of this new bitmap is to flag the memory pages that are in
> the middle of LL/SC operations (after a LL, before a SC).
> For all these pages, the corresponding TLB entries will be generated
> in such a way to force the slow-path.
> 
> The accessors to this bitmap are currently not atomic, but they have to
> be so in a real multi-threading TCG.
> 
> Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com>
> Suggested-by: Claudio Fontana <claudio.fontana@huawei.com>
> Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
> ---
>  include/exec/cpu-defs.h |  2 ++
>  include/exec/memory.h   |  3 ++-
>  include/exec/ram_addr.h | 19 ++++++++++++++++++-
>  3 files changed, 22 insertions(+), 2 deletions(-)
> 
> diff --git a/include/exec/cpu-defs.h b/include/exec/cpu-defs.h
> index 0ca6f0b..d12cb4c 100644
> --- a/include/exec/cpu-defs.h
> +++ b/include/exec/cpu-defs.h
> @@ -123,5 +123,7 @@ QEMU_BUILD_BUG_ON(sizeof(CPUTLBEntry) != (1 << CPU_TLB_ENTRY_BITS));
>  #define CPU_COMMON                                                      \
>      /* soft mmu support */                                              \
>      CPU_COMMON_TLB                                                      \
> +    /* true if in the middle of a LoadLink/StoreConditional */          \
> +    bool ll_sc_context;                                                 \

Belongs to a different patch?


r~