4.16-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mike Marciniszyn <[email protected]> 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: <[email protected]> # 4.14.x Reviewed-by: Michael J. Ruhl <[email protected]> Signed-off-by: Mike Marciniszyn <[email protected]> Signed-off-by: Dennis Dalessandro <[email protected]> Signed-off-by: Doug Ledford <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/infiniband/hw/hfi1/ruc.c | 50 +++++++++++++++++++++++++++++++-------- 1 file changed, 40 insertions(+), 10 deletions(-) --- a/drivers/infiniband/hw/hfi1/ruc.c +++ b/drivers/infiniband/hw/hfi1/ruc.c @@ -733,6 +733,20 @@ static inline void hfi1_make_ruc_bth(str 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, @@ -777,6 +791,12 @@ static inline void hfi1_make_ruc_header_ 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 @@ -784,11 +804,6 @@ static inline void hfi1_make_ruc_header_ 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 = true; - } hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2); if (!ppd->lid) @@ -806,6 +821,20 @@ static inline void hfi1_make_ruc_header_ 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, @@ -839,6 +868,12 @@ static inline void hfi1_make_ruc_header_ 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 @@ -846,11 +881,6 @@ static inline void hfi1_make_ruc_header_ 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); hfi1_make_ib_hdr(&ps->s_txreq->phdr.hdr.ibh, lrh0,
