Re: [Qemu-devel] [RFC v7 05/16] softmmu: Add new TLB_EXCL flag

["Alex Bennée" <alex.bennee@linaro.org>]

Alvise Rigo <a.rigo@virtualopensystems.com> writes:

> Add a new TLB flag to force all the accesses made to a page to follow
> the slow-path.
>
> The TLB entries referring guest pages with the DIRTY_MEMORY_EXCLUSIVE
> bit clean will have this flag set.
>
> 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-all.h | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
> index 83b1781..f8d8feb 100644
> --- a/include/exec/cpu-all.h
> +++ b/include/exec/cpu-all.h
> @@ -277,6 +277,14 @@ CPUArchState *cpu_copy(CPUArchState *env);
>  #define TLB_NOTDIRTY    (1 << 4)
>  /* Set if TLB entry is an IO callback.  */
>  #define TLB_MMIO        (1 << 5)
> +/* Set if TLB entry references a page that requires exclusive access.  */
> +#define TLB_EXCL        (1 << 6)
> +
> +/* Do not allow a TARGET_PAGE_MASK which covers one or more bits defined
> + * above. */
> +#if TLB_EXCL >= TARGET_PAGE_SIZE
> +#error TARGET_PAGE_MASK covering the low bits of the TLB virtual address
> +#endif
>
>  void dump_exec_info(FILE *f, fprintf_function cpu_fprintf);
>  void dump_opcount_info(FILE *f, fprintf_function cpu_fprintf);

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

--
Alex Bennée