From 1393109f23f8ad753a60a3e461c6caa96d8524f3 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Tue, 21 Apr 2009 15:32:34 -0500 Subject: [SCSI] cxgb3i: fix cpu use abuse during writes When doing a lot (128) of large writes (256K) we can hit the cxgb3_snd_win check pretty easily. The driver's xmit thread then takes 100% of the cpu. The driver should not be returning -EAGAIN for this problem. It should be returing -ENOBUFS, then when the window is opened again it should queue the xmit thread (it already wakes the xmit thread). Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- drivers/scsi/cxgb3i/cxgb3i_offload.c | 4 +++- drivers/scsi/cxgb3i/cxgb3i_pdu.c | 19 ++++++++++--------- 2 files changed, 13 insertions(+), 10 deletions(-) (limited to 'drivers') diff --git a/drivers/scsi/cxgb3i/cxgb3i_offload.c b/drivers/scsi/cxgb3i/cxgb3i_offload.c index 4d8654cdbdae..e11c9c180f39 100644 --- a/drivers/scsi/cxgb3i/cxgb3i_offload.c +++ b/drivers/scsi/cxgb3i/cxgb3i_offload.c @@ -1737,7 +1737,7 @@ int cxgb3i_c3cn_send_pdus(struct s3_conn *c3cn, struct sk_buff *skb) c3cn_tx_debug("c3cn 0x%p, snd %u - %u > %u.\n", c3cn, c3cn->write_seq, c3cn->snd_una, cxgb3_snd_win); - err = -EAGAIN; + err = -ENOBUFS; goto out_err; } @@ -1775,6 +1775,8 @@ done: out_err: if (copied == 0 && err == -EPIPE) copied = c3cn->err ? c3cn->err : -EPIPE; + else + copied = err; goto done; } diff --git a/drivers/scsi/cxgb3i/cxgb3i_pdu.c b/drivers/scsi/cxgb3i/cxgb3i_pdu.c index 7eebc9a7cb35..709105071177 100644 --- a/drivers/scsi/cxgb3i/cxgb3i_pdu.c +++ b/drivers/scsi/cxgb3i/cxgb3i_pdu.c @@ -400,17 +400,18 @@ int cxgb3i_conn_xmit_pdu(struct iscsi_task *task) return 0; } - if (err < 0 && err != -EAGAIN) { - kfree_skb(skb); - cxgb3i_tx_debug("itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n", - task->itt, skb, skb->len, skb->data_len, err); - iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err); - iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED); + if (err == -EAGAIN || err == -ENOBUFS) { + /* reset skb to send when we are called again */ + tdata->skb = skb; return err; } - /* reset skb to send when we are called again */ - tdata->skb = skb; - return -EAGAIN; + + kfree_skb(skb); + cxgb3i_tx_debug("itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n", + task->itt, skb, skb->len, skb->data_len, err); + iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err); + iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED); + return err; } int cxgb3i_pdu_init(void) -- cgit v1.2.3