diff options
Diffstat (limited to 'net/rds/ib_frmr.c')
| -rw-r--r-- | net/rds/ib_frmr.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/net/rds/ib_frmr.c b/net/rds/ib_frmr.c index adaa8e99e5a9..06ecf9d2d4bf 100644 --- a/net/rds/ib_frmr.c +++ b/net/rds/ib_frmr.c @@ -32,6 +32,24 @@ #include "ib_mr.h" +static inline void +rds_transition_frwr_state(struct rds_ib_mr *ibmr, + enum rds_ib_fr_state old_state, + enum rds_ib_fr_state new_state) +{ + if (cmpxchg(&ibmr->u.frmr.fr_state, + old_state, new_state) == old_state && + old_state == FRMR_IS_INUSE) { + /* enforce order of ibmr->u.frmr.fr_state update + * before decrementing i_fastreg_inuse_count + */ + smp_mb__before_atomic(); + atomic_dec(&ibmr->ic->i_fastreg_inuse_count); + if (waitqueue_active(&rds_ib_ring_empty_wait)) + wake_up(&rds_ib_ring_empty_wait); + } +} + static struct rds_ib_mr *rds_ib_alloc_frmr(struct rds_ib_device *rds_ibdev, int npages) { @@ -118,13 +136,18 @@ static int rds_ib_post_reg_frmr(struct rds_ib_mr *ibmr) if (unlikely(ret != ibmr->sg_len)) return ret < 0 ? ret : -EINVAL; + if (cmpxchg(&frmr->fr_state, + FRMR_IS_FREE, FRMR_IS_INUSE) != FRMR_IS_FREE) + return -EBUSY; + + atomic_inc(&ibmr->ic->i_fastreg_inuse_count); + /* Perform a WR for the fast_reg_mr. Each individual page * in the sg list is added to the fast reg page list and placed * inside the fast_reg_mr WR. The key used is a rolling 8bit * counter, which should guarantee uniqueness. */ ib_update_fast_reg_key(frmr->mr, ibmr->remap_count++); - frmr->fr_state = FRMR_IS_INUSE; frmr->fr_reg = true; memset(®_wr, 0, sizeof(reg_wr)); @@ -141,7 +164,8 @@ static int rds_ib_post_reg_frmr(struct rds_ib_mr *ibmr) ret = ib_post_send(ibmr->ic->i_cm_id->qp, ®_wr.wr, NULL); if (unlikely(ret)) { /* Failure here can be because of -ENOMEM as well */ - frmr->fr_state = FRMR_IS_STALE; + rds_transition_frwr_state(ibmr, FRMR_IS_INUSE, FRMR_IS_STALE); + atomic_inc(&ibmr->ic->i_fastreg_wrs); if (printk_ratelimit()) pr_warn("RDS/IB: %s returned error(%d)\n", @@ -268,8 +292,12 @@ static int rds_ib_post_inv(struct rds_ib_mr *ibmr) ret = ib_post_send(i_cm_id->qp, s_wr, NULL); if (unlikely(ret)) { - frmr->fr_state = FRMR_IS_STALE; + rds_transition_frwr_state(ibmr, FRMR_IS_INUSE, FRMR_IS_STALE); frmr->fr_inv = false; + /* enforce order of frmr->fr_inv update + * before incrementing i_fastreg_wrs + */ + smp_mb__before_atomic(); atomic_inc(&ibmr->ic->i_fastreg_wrs); pr_err("RDS/IB: %s returned error(%d)\n", __func__, ret); goto out; @@ -297,7 +325,7 @@ void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc) struct rds_ib_frmr *frmr = &ibmr->u.frmr; if (wc->status != IB_WC_SUCCESS) { - frmr->fr_state = FRMR_IS_STALE; + rds_transition_frwr_state(ibmr, FRMR_IS_INUSE, FRMR_IS_STALE); if (rds_conn_up(ic->conn)) rds_ib_conn_error(ic->conn, "frmr completion <%pI4,%pI4> status %u(%s), vendor_err 0x%x, disconnecting and reconnecting\n", @@ -309,8 +337,7 @@ void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc) } if (frmr->fr_inv) { - if (frmr->fr_state == FRMR_IS_INUSE) - frmr->fr_state = FRMR_IS_FREE; + rds_transition_frwr_state(ibmr, FRMR_IS_INUSE, FRMR_IS_FREE); frmr->fr_inv = false; wake_up(&frmr->fr_inv_done); } @@ -320,6 +347,10 @@ void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc) wake_up(&frmr->fr_reg_done); } + /* enforce order of frmr->{fr_reg,fr_inv} update + * before incrementing i_fastreg_wrs + */ + smp_mb__before_atomic(); atomic_inc(&ic->i_fastreg_wrs); } |