Re: [PATCH 2/2] enic: Silence Sparse Warning: "dubious: x | !y"

From: walter harms
Date: Fri Feb 24 2012 - 12:27:51 EST




Am 24.02.2012 17:57, schrieb santosh nayak:
> From: Santosh Nayak <santoshprasadnayak@xxxxxxxxx>
>
> Sparse is giving the following warning:
> "warning: dubious: x | !y"
>
> "enic_are_pp_different" is static and expected to return true or false.
> Logical or is indended here. With logical or, in best case, execution will be
> faster because if leftmost operand is true then no need to check other operands.
>
> Signed-off-by: Santosh Nayak <santoshprasadnayak@xxxxxxxxx>
> ---
> drivers/net/ethernet/cisco/enic/enic_pp.c | 8 ++++----
> 1 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/ethernet/cisco/enic/enic_pp.c b/drivers/net/ethernet/cisco/enic/enic_pp.c
> index dafea1e..3a6de22 100644
> --- a/drivers/net/ethernet/cisco/enic/enic_pp.c
> +++ b/drivers/net/ethernet/cisco/enic/enic_pp.c
> @@ -159,10 +159,10 @@ static int enic_unset_port_profile(struct enic *enic, int vf)
> static int enic_are_pp_different(struct enic_port_profile *pp1,
> struct enic_port_profile *pp2)
> {
> - return strcmp(pp1->name, pp2->name) |
!!memcmp(pp1->instance_uuid,pp2->instance_uuid, PORT_UUID_MAX) |
> - !!memcmp(pp1->host_uuid, pp2->host_uuid, PORT_UUID_MAX) |
> - !!memcmp(pp1->mac_addr, pp2->mac_addr, ETH_ALEN);
> + return strcmp(pp1->name, pp2->name) ||
!!memcmp(pp1->instance_uuid,pp2->instance_uuid, PORT_UUID_MAX) ||
> + !!memcmp(pp1->host_uuid, pp2->host_uuid, PORT_UUID_MAX) ||
> + !!memcmp(pp1->mac_addr, pp2->mac_addr, ETH_ALEN);
> }
>

to be fair, this is next to unreadable (not your fault of cause).
Instead of squeezing this into a one statement i would suggest more statements.

just my 2 cents,
re,
wh



> static int enic_pp_preassociate(struct enic *enic, int vf,
--
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