From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Wise Subject: [PATCH 05/11] RDMA/cxgb4: Fix overflow bug in cq arm. Date: Thu, 20 May 2010 16:57:49 -0500 Message-ID: <20100520215748.32394.1063.stgit@build.ogc.int> References: <20100520215727.32394.90669.stgit@build.ogc.int> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100520215727.32394.90669.stgit-T4OLL4TyM9aNDNWfRnPdfg@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org - wrap cq->cqidx_inc based on cq size. - optimize t4_arm_cq logic. Signed-off-by: Steve Wise --- drivers/infiniband/hw/cxgb4/t4.h | 31 ++++++++++++------------------- 1 files changed, 12 insertions(+), 19 deletions(-) diff --git a/drivers/infiniband/hw/cxgb4/t4.h b/drivers/infiniband/hw/cxgb4/t4.h index 712bc56..333abd3 100644 --- a/drivers/infiniband/hw/cxgb4/t4.h +++ b/drivers/infiniband/hw/cxgb4/t4.h @@ -449,25 +449,17 @@ struct t4_cq { static inline int t4_arm_cq(struct t4_cq *cq, int se) { u32 val; - u16 inc; - - do { - /* - * inc must be less the both the max update value -and- - * the size of the CQ. - */ - inc = cq->cidx_inc <= CIDXINC_MASK ? cq->cidx_inc : - CIDXINC_MASK; - inc = inc <= (cq->size - 1) ? inc : (cq->size - 1); - if (inc == cq->cidx_inc) - val = SEINTARM(se) | CIDXINC(inc) | TIMERREG(6) | - INGRESSQID(cq->cqid); - else - val = SEINTARM(0) | CIDXINC(inc) | TIMERREG(7) | - INGRESSQID(cq->cqid); - cq->cidx_inc -= inc; + + while (cq->cidx_inc > CIDXINC_MASK) { + val = SEINTARM(0) | CIDXINC(CIDXINC_MASK) | TIMERREG(7) | + INGRESSQID(cq->cqid); writel(val, cq->gts); - } while (cq->cidx_inc); + cq->cidx_inc -= CIDXINC_MASK; + } + val = SEINTARM(se) | CIDXINC(cq->cidx_inc) | TIMERREG(6) | + INGRESSQID(cq->cqid); + writel(val, cq->gts); + cq->cidx_inc = 0; return 0; } @@ -488,7 +480,8 @@ static inline void t4_swcq_consume(struct t4_cq *cq) static inline void t4_hwcq_consume(struct t4_cq *cq) { cq->bits_type_ts = cq->queue[cq->cidx].bits_type_ts; - cq->cidx_inc++; + if (++cq->cidx_inc == cq->size) + cq->cidx_inc = 0; if (++cq->cidx == cq->size) { cq->cidx = 0; cq->gen ^= 1; -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html