Am 17.01.2012 14:23, schrieb Peter Maydell:
> Clarify the comment about tlb_flush()'s flush_global parameter,
> so it is clearer what it does and why it is OK that the implementation
> currently ignores it.
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
Reviewed-by: Andreas Färber <afaer...@suse.de>
CC'ing qemu-trivial.
Andreas
> ---
> Minor clarification following a conversation on IRC...
>
> exec.c | 14 ++++++++++++--
> 1 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index 7f9f730..f667cf0 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1876,8 +1876,18 @@ static CPUTLBEntry s_cputlb_empty_entry = {
> .addend = -1,
> };
>
> -/* NOTE: if flush_global is true, also flush global entries (not
> - implemented yet) */
> +/* NOTE:
> + * If flush_global is true (the usual case), flush all tlb entries.
> + * If flush_global is false, flush (at least) all tlb entries not
> + * marked global.
> + *
> + * Since QEMU doesn't currently implement a global/not-global flag
> + * for tlb entries, at the moment tlb_flush() will also flush all
> + * tlb entries in the flush_global == false case. This is OK because
> + * CPU architectures generally permit an implementation to drop
> + * entries from the TLB at any time, so flushing more entries than
> + * required is only an efficiency issue, not a correctness issue.
> + */
> void tlb_flush(CPUState *env, int flush_global)
> {
> int i;
--
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