I think this patch (on top of the previous one) actually makes the code clearer, and also makes it smaller: add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-41 (-41) function old new delta mthca_tavor_post_send 1344 1335 -9 mthca_tavor_post_receive 792 776 -16 mthca_arbel_post_send 1481 1465 -16 So I'll test this a bit and probably merge it. --- diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c index 0e9ef24..186bade 100644 --- a/drivers/infiniband/hw/mthca/mthca_qp.c +++ b/drivers/infiniband/hw/mthca/mthca_qp.c @@ -1590,13 +1590,14 @@ int mthca_tavor_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, int nreq; int i; int size; - int size0 = 0; /* - * f0 is only used if nreq != 0, and f0 will be initialized - * the first time through the main loop, since size0 == 0 the - * first time through. So nreq cannot become non-zero without - * initializing f0, and f0 is in fact never used uninitialized. + * f0 and size0 are only used if nreq != 0, and they will + * always be initialized the first time through the main loop + * before nreq is incremented. So nreq cannot become non-zero + * without initializing f0 and size0, and they are in fact + * never used uninitialized. */ + int uninitialized_var(size0); u32 uninitialized_var(f0); int ind; u8 op0 = 0; @@ -1774,11 +1775,11 @@ int mthca_tavor_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, mthca_opcode[wr->opcode]); wmb(); ((struct mthca_next_seg *) prev_wqe)->ee_nds = - cpu_to_be32((size0 ? 0 : MTHCA_NEXT_DBD) | size | + cpu_to_be32((nreq ? 0 : MTHCA_NEXT_DBD) | size | ((wr->send_flags & IB_SEND_FENCE) ? MTHCA_NEXT_FENCE : 0)); - if (!size0) { + if (!nreq) { size0 = size; op0 = mthca_opcode[wr->opcode]; f0 = wr->send_flags & IB_SEND_FENCE ? @@ -1828,7 +1829,14 @@ int mthca_tavor_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, int nreq; int i; int size; - int size0 = 0; + /* + * size0 is only used if nreq != 0, and it will always be + * initialized the first time through the main loop before + * nreq is incremented. So nreq cannot become non-zero + * without initializing size0, and it is in fact never used + * uninitialized. + */ + int uninitialized_var(size0); int ind; void *wqe; void *prev_wqe; @@ -1887,7 +1895,7 @@ int mthca_tavor_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, ((struct mthca_next_seg *) prev_wqe)->ee_nds = cpu_to_be32(MTHCA_NEXT_DBD | size); - if (!size0) + if (!nreq) size0 = size; ++ind; @@ -1909,7 +1917,6 @@ int mthca_tavor_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, qp->rq.next_ind = ind; qp->rq.head += MTHCA_TAVOR_MAX_WQES_PER_RECV_DB; - size0 = 0; } } @@ -1951,13 +1958,14 @@ int mthca_arbel_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, int nreq; int i; int size; - int size0 = 0; /* - * f0 is only used if nreq != 0, and f0 will be initialized - * the first time through the main loop, since size0 == 0 the - * first time through. So nreq cannot become non-zero without - * initializing f0, and f0 is in fact never used uninitialized. + * f0 and size0 are only used if nreq != 0, and they will + * always be initialized the first time through the main loop + * before nreq is incremented. So nreq cannot become non-zero + * without initializing f0 and size0, and they are in fact + * never used uninitialized. */ + int uninitialized_var(size0); u32 uninitialized_var(f0); int ind; u8 op0 = 0; @@ -1978,7 +1986,6 @@ int mthca_arbel_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, doorbell[1] = cpu_to_be32((qp->qpn << 8) | size0); qp->sq.head += MTHCA_ARBEL_MAX_WQES_PER_SEND_DB; - size0 = 0; /* * Make sure that descriptors are written before @@ -2163,7 +2170,7 @@ int mthca_arbel_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, ((wr->send_flags & IB_SEND_FENCE) ? MTHCA_NEXT_FENCE : 0)); - if (!size0) { + if (!nreq) { size0 = size; op0 = mthca_opcode[wr->opcode]; f0 = wr->send_flags & IB_SEND_FENCE ? - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html