On Mon, Jan 25, 2016 at 10:37:42AM -0800, Andy Lutomirski wrote:
> This adds helpers for each of the four currently-specified INVPCID
> modes.
>
> Signed-off-by: Andy Lutomirski <[email protected]>
> ---
> arch/x86/include/asm/tlbflush.h | 41
> +++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 41 insertions(+)
>
> diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
> index 6df2029405a3..20fc38d8478a 100644
> --- a/arch/x86/include/asm/tlbflush.h
> +++ b/arch/x86/include/asm/tlbflush.h
> @@ -7,6 +7,47 @@
> #include <asm/processor.h>
> #include <asm/special_insns.h>
>
> +static inline void __invpcid(unsigned long pcid, unsigned long addr,
> + unsigned long type)
> +{
> + u64 desc[2] = { pcid, addr };
> +
> + /*
> + * The memory clobber is because the whole point is to invalidate
> + * stale TLB entries and, especially if we're flushing global
> + * mappings, we don't want the compiler to reorder any subsequent
> + * memory accesses before the TLB flush.
> + */
> + asm volatile (
Yeah, no need for that linebreak here:
asm volatile (".byte 0x66, 0x0f, 0x38, 0x82, 0x01"
reads fine too.
> + ".byte 0x66, 0x0f, 0x38, 0x82, 0x01" /* invpcid (%cx), %ax */
> + : : "m" (desc), "a" (type), "c" (desc) : "memory");
> +}
> +
Please add defines for the invalidation types:
#define INVPCID_TYPE_INDIVIDUAL 0
#define INVPCID_TYPE_SINGLE_CTXT 1
#define INVPCID_TYPE_ALL 2
#define INVPCID_TYPE_ALL_NON_GLOBAL 3
and add macros:
#define invpcid_flush_one(pcid, addr) __invpcid(pcid, addr,
INVPCID_TYPE_INDIVIDUAL)
...
and so on.
Oh, and the "flush everything" macro I'd call invpcid_flush_all() like
tlb_flush_all().
Thanks.
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
