From f130c2205dba8f02372c794c6c4e6cc4906376f4 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 11 Feb 2016 11:05:38 -0800 Subject: [PATCH] IB/srpt: Simplify channel state management The only allowed channel state changes are those that change the channel state into a state with a higher numerical value. This allows to merge the functions srpt_set_ch_state() and srpt_test_and_set_ch_state() into a single function. Signed-off-by: Bart Van Assche Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Cc: Alex Estrin Signed-off-by: Doug Ledford --- drivers/infiniband/ulp/srpt/ib_srpt.c | 44 ++++++++------------------- 1 file changed, 13 insertions(+), 31 deletions(-) diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c index 716f4292838a..863fdd130b2b 100644 --- a/drivers/infiniband/ulp/srpt/ib_srpt.c +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c @@ -96,37 +96,25 @@ static int srpt_queue_status(struct se_cmd *cmd); static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc); static void srpt_send_done(struct ib_cq *cq, struct ib_wc *wc); -static enum rdma_ch_state -srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new_state) -{ - unsigned long flags; - enum rdma_ch_state prev; - - spin_lock_irqsave(&ch->spinlock, flags); - prev = ch->state; - ch->state = new_state; - spin_unlock_irqrestore(&ch->spinlock, flags); - return prev; -} - -/** - * srpt_test_and_set_ch_state() - Test and set the channel state. - * - * Returns true if and only if the channel state has been set to the new state. +/* + * The only allowed channel state changes are those that change the channel + * state into a state with a higher numerical value. Hence the new > prev test. */ -static bool -srpt_test_and_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state old, - enum rdma_ch_state new) +static bool srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new) { unsigned long flags; enum rdma_ch_state prev; + bool changed = false; spin_lock_irqsave(&ch->spinlock, flags); prev = ch->state; - if (prev == old) + if (new > prev) { ch->state = new; + changed = true; + } spin_unlock_irqrestore(&ch->spinlock, flags); - return prev == old; + + return changed; } /** @@ -199,8 +187,7 @@ static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch) ib_cm_notify(ch->cm_id, event->event); break; case IB_EVENT_QP_LAST_WQE_REACHED: - if (srpt_test_and_set_ch_state(ch, CH_DRAINING, - CH_RELEASING)) + if (srpt_set_ch_state(ch, CH_RELEASING)) srpt_release_channel(ch); else pr_debug("%s: state %d - ignored LAST_WQE.\n", @@ -1947,12 +1934,7 @@ static void srpt_drain_channel(struct ib_cm_id *cm_id) spin_lock_irq(&sdev->spinlock); list_for_each_entry(ch, &sdev->rch_list, list) { if (ch->cm_id == cm_id) { - do_reset = srpt_test_and_set_ch_state(ch, - CH_CONNECTING, CH_DRAINING) || - srpt_test_and_set_ch_state(ch, - CH_LIVE, CH_DRAINING) || - srpt_test_and_set_ch_state(ch, - CH_DISCONNECTING, CH_DRAINING); + do_reset = srpt_set_ch_state(ch, CH_DRAINING); break; } } @@ -2353,7 +2335,7 @@ static void srpt_cm_rtu_recv(struct ib_cm_id *cm_id) ch = srpt_find_channel(cm_id->context, cm_id); BUG_ON(!ch); - if (srpt_test_and_set_ch_state(ch, CH_CONNECTING, CH_LIVE)) { + if (srpt_set_ch_state(ch, CH_LIVE)) { struct srpt_recv_ioctx *ioctx, *ioctx_tmp; ret = srpt_ch_qp_rts(ch, ch->qp);