Re: [Qemu-devel] [PATCH] include: Add roundup_pow_of_two helper function

[Marcel Apfelbaum <marcel@redhat.com>]

On 11/28/2016 09:18 AM, Yuval Shaia wrote:
> Move private implementation of rthe function to osdep.h

Hi Yuval,

In my opinion we need to use the function in at least
two places in order to promote it to a global utility.

You are welcome to try to find another place needing it.

Thanks,
Marcel

>
> Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
> ---
>  hw/pci/shpc.c        | 12 +-----------
>  include/qemu/osdep.h | 10 ++++++++++
>  2 files changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/hw/pci/shpc.c b/hw/pci/shpc.c
> index 3dcd472..4b8982d 100644
> --- a/hw/pci/shpc.c
> +++ b/hw/pci/shpc.c
> @@ -122,16 +122,6 @@
>  #define SHPC_PCI_TO_IDX(pci_slot) ((pci_slot) - 1)
>  #define SHPC_IDX_TO_PHYSICAL(slot) ((slot) + 1)
>
> -static int roundup_pow_of_two(int x)
> -{
> -    x |= (x >> 1);
> -    x |= (x >> 2);
> -    x |= (x >> 4);
> -    x |= (x >> 8);
> -    x |= (x >> 16);
> -    return x + 1;
> -}
> -
>  static uint16_t shpc_get_status(SHPCDevice *shpc, int slot, uint16_t msk)
>  {
>      uint8_t *status = shpc->config + SHPC_SLOT_STATUS(slot);
> @@ -654,7 +644,7 @@ int shpc_init(PCIDevice *d, PCIBus *sec_bus, MemoryRegion *bar, unsigned offset)
>
>  int shpc_bar_size(PCIDevice *d)
>  {
> -    return roundup_pow_of_two(SHPC_SLOT_REG(SHPC_MAX_SLOTS));
> +    return round_up_pow_of_two(SHPC_SLOT_REG(SHPC_MAX_SLOTS));
>  }
>
>  void shpc_cleanup(PCIDevice *d, MemoryRegion *bar)
> diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
> index 689f253..74d5c30 100644
> --- a/include/qemu/osdep.h
> +++ b/include/qemu/osdep.h
> @@ -194,6 +194,16 @@ extern int daemon(int, int);
>  #define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
>  #endif
>
> +static inline int round_up_pow_of_two(int x)
> +{
> +	x |= (x >> 1);
> +	x |= (x >> 2);
> +	x |= (x >> 4);
> +	x |= (x >> 8);
> +	x |= (x >> 16);
> +	return x + 1;
> +}
> +
>  #ifndef DIV_ROUND_UP
>  #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
>  #endif
>