2015-06-19 03:15:21

by Vaishali Thakkar

Subject: [PATCH] aoe: Convert use of __constant_<foo> to <foo>

In little endian cases, the macros htons and cpu_to_be16 unfolds
to __swab16 which provides special case for constants. In big
endian cases, __constant_htons and htons expand directly to the
same expression. The same applies for __constant_cpu_to_be16 and
cpu_to_be16.

So, replace __constant_htons with htons and __constant_cpu_to_be16
with cpu_to_be16 with the goal of getting rid of the definitions
__constant_htons and __constant_cpu_to_be16 completely.

The semantic patch that performs this transformation is as follows:

@@expression x;@@

(
- __constant_htons(x)
+ htons(x)
|
- __constant_cpu_to_be16(x)
+ cpu_to_be16(x)
)

Signed-off-by: Vaishali Thakkar <[email protected]>
---
drivers/block/aoe/aoecmd.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 422b7d8..6e891d2 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -69,7 +69,7 @@ new_skb(ulong len)
skb_reserve(skb, MAX_HEADER);
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
- skb->protocol = __constant_htons(ETH_P_AOE);
+ skb->protocol = htons(ETH_P_AOE);
skb_checksum_none_assert(skb);
}
return skb;
@@ -132,7 +132,7 @@ aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)

memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
memcpy(h->dst, t->addr, sizeof h->dst);
- h->type = __constant_cpu_to_be16(ETH_P_AOE);
+ h->type = cpu_to_be16(ETH_P_AOE);
h->verfl = AOE_HVER;
h->major = cpu_to_be16(d->aoemajor);
h->minor = d->aoeminor;
@@ -437,7 +437,7 @@ aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *qu

memset(h->dst, 0xff, sizeof h->dst);
memcpy(h->src, ifp->dev_addr, sizeof h->src);
- h->type = __constant_cpu_to_be16(ETH_P_AOE);
+ h->type = cpu_to_be16(ETH_P_AOE);
h->verfl = AOE_HVER;
h->major = cpu_to_be16(aoemajor);
h->minor = aoeminor;
--
1.9.1

2015-06-20 00:51:53

by Ed Cashin

Subject: Re: [PATCH] aoe: Convert use of __constant_<foo> to <foo>

OK. Thanks.

On 06/18/2015 11:15 PM, Vaishali Thakkar wrote:
> In little endian cases, the macros htons and cpu_to_be16 unfolds
> to __swab16 which provides special case for constants. In big
> endian cases, __constant_htons and htons expand directly to the
> same expression. The same applies for __constant_cpu_to_be16 and
> cpu_to_be16.
>
> So, replace __constant_htons with htons and __constant_cpu_to_be16
> with cpu_to_be16 with the goal of getting rid of the definitions
> __constant_htons and __constant_cpu_to_be16 completely.
>
> The semantic patch that performs this transformation is as follows:
>
> @@expression x;@@
>
> (
> - __constant_htons(x)
> + htons(x)
> |
> - __constant_cpu_to_be16(x)
> + cpu_to_be16(x)
> )
>
> Signed-off-by: Vaishali Thakkar <[email protected]>
> ---
> drivers/block/aoe/aoecmd.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
> index 422b7d8..6e891d2 100644
> --- a/drivers/block/aoe/aoecmd.c
> +++ b/drivers/block/aoe/aoecmd.c
> @@ -69,7 +69,7 @@ new_skb(ulong len)
> skb_reserve(skb, MAX_HEADER);
> skb_reset_mac_header(skb);
> skb_reset_network_header(skb);
> - skb->protocol = __constant_htons(ETH_P_AOE);
> + skb->protocol = htons(ETH_P_AOE);
> skb_checksum_none_assert(skb);
> }
> return skb;
> @@ -132,7 +132,7 @@ aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
>
> memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
> memcpy(h->dst, t->addr, sizeof h->dst);
> - h->type = __constant_cpu_to_be16(ETH_P_AOE);
> + h->type = cpu_to_be16(ETH_P_AOE);
> h->verfl = AOE_HVER;
> h->major = cpu_to_be16(d->aoemajor);
> h->minor = d->aoeminor;
> @@ -437,7 +437,7 @@ aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *qu
>
> memset(h->dst, 0xff, sizeof h->dst);
> memcpy(h->src, ifp->dev_addr, sizeof h->src);
> - h->type = __constant_cpu_to_be16(ETH_P_AOE);
> + h->type = cpu_to_be16(ETH_P_AOE);
> h->verfl = AOE_HVER;
> h->major = cpu_to_be16(aoemajor);
> h->minor = aoeminor;