RDMA/ocrdma: Use unsigned for bit index
authorRasmus Villemoes <linux@rasmusvillemoes.dk>
Fri, 16 Jan 2015 14:39:56 +0000 (15:39 +0100)
committerRoland Dreier <roland@purestorage.com>
Wed, 18 Feb 2015 16:31:06 +0000 (08:31 -0800)
In the expressions idx/32 and idx%32, both idx and 32 have signed
type, and unfortunately the C standard prescribes rounding to 0, so
unless gcc can prove that idx is non-negative, these cannot be
implemented as simple shift respectively mask operations. Help gcc by
changing the type of idx to unsigned - this cuts another few
instructions from the generated code.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Selvin Xavier <selvin.xavier@emulex.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
drivers/infiniband/hw/ocrdma/ocrdma_verbs.c

index c1e9f96..397a367 100644 (file)
@@ -1586,10 +1586,10 @@ mbx_err:
        return status;
 }
 
-static void ocrdma_srq_toggle_bit(struct ocrdma_srq *srq, int idx)
+static void ocrdma_srq_toggle_bit(struct ocrdma_srq *srq, unsigned int idx)
 {
-       int i = idx / 32;
-       unsigned int mask = (1 << (idx % 32));
+       unsigned int i = idx / 32;
+       u32 mask = (1U << (idx % 32));
 
        srq->idx_bit_fields[i] ^= mask;
 }