On Mon, Jul 28, 2025 at 07:26:36PM -0700, Yuzhuo Jing wrote:
> Import only prefetch and prefetchw but not page and range related
> methods.
>
> Signed-off-by: Yuzhuo Jing <yuzhuo@google.com>
> ---
> tools/include/linux/prefetch.h | 41 ++++++++++++++++++++++++++++++++++
> 1 file changed, 41 insertions(+)
> create mode 100644 tools/include/linux/prefetch.h
>
> diff --git a/tools/include/linux/prefetch.h b/tools/include/linux/prefetch.h
> new file mode 100644
> index 000000000000..1ed8678f4824
> --- /dev/null
> +++ b/tools/include/linux/prefetch.h
> @@ -0,0 +1,41 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Generic cache management functions. Everything is arch-specific,
> + * but this header exists to make sure the defines/functions can be
> + * used in a generic way.
> + *
> + * 2000-11-13 Arjan van de Ven <arjan@fenrus.demon.nl>
> + *
> + */
> +
> +#ifndef _LINUX_PREFETCH_H
> +#define _LINUX_PREFETCH_H
> +
> +/*
> + prefetch(x) attempts to pre-emptively get the memory pointed to
> + by address "x" into the CPU L1 cache.
> + prefetch(x) should not cause any kind of exception, prefetch(0) is
> + specifically ok.
> +
> + prefetch() should be defined by the architecture, if not, the
> + #define below provides a no-op define.
> +
> + There are 2 prefetch() macros:
> +
> + prefetch(x) - prefetches the cacheline at "x" for read
> + prefetchw(x) - prefetches the cacheline at "x" for write
> +
> + there is also PREFETCH_STRIDE which is the architecure-preferred
> + "lookahead" size for prefetching streamed operations.
> +
> +*/
> +
> +#ifndef ARCH_HAS_PREFETCH
> +#define prefetch(x) __builtin_prefetch(x)
> +#endif
Do we have ARCH_HAS_PREFETCH somewhere?
Thanks,
Namhyung
> +
> +#ifndef ARCH_HAS_PREFETCHW
> +#define prefetchw(x) __builtin_prefetch(x,1)
> +#endif
> +
> +#endif
> --
> 2.50.1.487.gc89ff58d15-goog
>