From 79181a45aa9a2427c6320a2d50e8710fc6931cce Mon Sep 17 00:00:00 2001 From: Mike Marciniszyn Date: Tue, 1 May 2018 05:35:51 -0700 Subject: [PATCH] IB/hfi1: Fix loss of BECN with AHG commit 0a0bcb046b2f0c15b89f8c1b08ad3de601a83c66 upstream. AHG may be armed to use the stored header, which by design is limited to edits in the PSN/A 32 bit word (bth2). When the code is trying to send a BECN, the use of the stored header will lose the BECN bit. Fix by avoiding AHG when getting ready to send a BECN. This is accomplished by always claiming the packet is not a middle packet which is an AHG precursor. BECNs are not a normal case and this should not hurt AHG optimizations. Cc: # 4.14.x Reviewed-by: Michael J. Ruhl Signed-off-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/hfi1/ruc.c | 50 +++++++++++++++++++++++++------- 1 file changed, 40 insertions(+), 10 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/ruc.c b/drivers/infiniband/hw/hfi1/ruc.c index b3291f0fde9a..5866ccc0fc21 100644 --- a/drivers/infiniband/hw/hfi1/ruc.c +++ b/drivers/infiniband/hw/hfi1/ruc.c @@ -745,6 +745,20 @@ static inline void hfi1_make_ruc_bth(struct rvt_qp *qp, ohdr->bth[2] = cpu_to_be32(bth2); } +/** + * hfi1_make_ruc_header_16B - build a 16B header + * @qp: the queue pair + * @ohdr: a pointer to the destination header memory + * @bth0: bth0 passed in from the RC/UC builder + * @bth2: bth2 passed in from the RC/UC builder + * @middle: non zero implies indicates ahg "could" be used + * @ps: the current packet state + * + * This routine may disarm ahg under these situations: + * - packet needs a GRH + * - BECN needed + * - migration state not IB_MIG_MIGRATED + */ static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp, struct ib_other_headers *ohdr, u32 bth0, u32 bth2, int middle, @@ -789,6 +803,12 @@ static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp, else middle = 0; + if (qp->s_flags & RVT_S_ECN) { + qp->s_flags &= ~RVT_S_ECN; + /* we recently received a FECN, so return a BECN */ + becn = true; + middle = 0; + } if (middle) build_ahg(qp, bth2); else @@ -796,11 +816,6 @@ static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp, bth0 |= pkey; bth0 |= extra_bytes << 20; - if (qp->s_flags & RVT_S_ECN) { - qp->s_flags &= ~RVT_S_ECN; - /* we recently received a FECN, so return a BECN */ - becn = 1; - } hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2); if (!ppd->lid) @@ -818,6 +833,20 @@ static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp, pkey, becn, 0, l4, priv->s_sc); } +/** + * hfi1_make_ruc_header_9B - build a 9B header + * @qp: the queue pair + * @ohdr: a pointer to the destination header memory + * @bth0: bth0 passed in from the RC/UC builder + * @bth2: bth2 passed in from the RC/UC builder + * @middle: non zero implies indicates ahg "could" be used + * @ps: the current packet state + * + * This routine may disarm ahg under these situations: + * - packet needs a GRH + * - BECN needed + * - migration state not IB_MIG_MIGRATED + */ static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp, struct ib_other_headers *ohdr, u32 bth0, u32 bth2, int middle, @@ -853,6 +882,12 @@ static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp, else middle = 0; + if (qp->s_flags & RVT_S_ECN) { + qp->s_flags &= ~RVT_S_ECN; + /* we recently received a FECN, so return a BECN */ + bth1 |= (IB_BECN_MASK << IB_BECN_SHIFT); + middle = 0; + } if (middle) build_ahg(qp, bth2); else @@ -860,11 +895,6 @@ static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp, bth0 |= pkey; bth0 |= extra_bytes << 20; - if (qp->s_flags & RVT_S_ECN) { - qp->s_flags &= ~RVT_S_ECN; - /* we recently received a FECN, so return a BECN */ - bth1 |= (IB_BECN_MASK << IB_BECN_SHIFT); - } hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2); if (!ppd->lid) -- 2.20.1