From 1648b11ea7cec5b95e5a71364ac1f40bfef702d0 Mon Sep 17 00:00:00 2001 From: Karen Xie Date: Fri, 13 Feb 2009 21:38:44 -0800 Subject: [PATCH] [SCSI] cxgb3i: transmit work-request fixes - resize the work-request credit array to be based on skb's MAX_SKB_FRAGS. - split the skb cb into tx and rx portion - increase the default transmit window to 128K. - stop queueing up the outgoing pdus if transmit window is full. Signed-off-by: Karen Xie Reviewed-by: Mike Christie Signed-off-by: James Bottomley --- drivers/scsi/cxgb3i/cxgb3i_offload.c | 146 +++++++++++++++++++-------- drivers/scsi/cxgb3i/cxgb3i_offload.h | 28 +++-- 2 files changed, 121 insertions(+), 53 deletions(-) diff --git a/drivers/scsi/cxgb3i/cxgb3i_offload.c b/drivers/scsi/cxgb3i/cxgb3i_offload.c index a865f1fefe8..de3b3b614cc 100644 --- a/drivers/scsi/cxgb3i/cxgb3i_offload.c +++ b/drivers/scsi/cxgb3i/cxgb3i_offload.c @@ -23,19 +23,19 @@ #include "cxgb3i_ddp.h" #ifdef __DEBUG_C3CN_CONN__ -#define c3cn_conn_debug cxgb3i_log_info +#define c3cn_conn_debug cxgb3i_log_debug #else #define c3cn_conn_debug(fmt...) #endif #ifdef __DEBUG_C3CN_TX__ -#define c3cn_tx_debug cxgb3i_log_debug +#define c3cn_tx_debug cxgb3i_log_debug #else #define c3cn_tx_debug(fmt...) #endif #ifdef __DEBUG_C3CN_RX__ -#define c3cn_rx_debug cxgb3i_log_debug +#define c3cn_rx_debug cxgb3i_log_debug #else #define c3cn_rx_debug(fmt...) #endif @@ -47,9 +47,9 @@ static int cxgb3_rcv_win = 256 * 1024; module_param(cxgb3_rcv_win, int, 0644); MODULE_PARM_DESC(cxgb3_rcv_win, "TCP receive window in bytes (default=256KB)"); -static int cxgb3_snd_win = 64 * 1024; +static int cxgb3_snd_win = 128 * 1024; module_param(cxgb3_snd_win, int, 0644); -MODULE_PARM_DESC(cxgb3_snd_win, "TCP send window in bytes (default=64KB)"); +MODULE_PARM_DESC(cxgb3_snd_win, "TCP send window in bytes (default=128KB)"); static int cxgb3_rx_credit_thres = 10 * 1024; module_param(cxgb3_rx_credit_thres, int, 0644); @@ -301,8 +301,8 @@ static void act_open_req_arp_failure(struct t3cdev *dev, struct sk_buff *skb) static void skb_entail(struct s3_conn *c3cn, struct sk_buff *skb, int flags) { - CXGB3_SKB_CB(skb)->seq = c3cn->write_seq; - CXGB3_SKB_CB(skb)->flags = flags; + skb_tcp_seq(skb) = c3cn->write_seq; + skb_flags(skb) = flags; __skb_queue_tail(&c3cn->write_queue, skb); } @@ -457,12 +457,9 @@ static unsigned int wrlen __read_mostly; * The number of WRs needed for an skb depends on the number of fragments * in the skb and whether it has any payload in its main body. This maps the * length of the gather list represented by an skb into the # of necessary WRs. - * - * The max. length of an skb is controlled by the max pdu size which is ~16K. - * Also, assume the min. fragment length is the sector size (512), then add - * extra fragment counts for iscsi bhs and payload padding. + * The extra two fragments are for iscsi bhs and payload padding. */ -#define SKB_WR_LIST_SIZE (16384/512 + 3) +#define SKB_WR_LIST_SIZE (MAX_SKB_FRAGS + 2) static unsigned int skb_wrs[SKB_WR_LIST_SIZE] __read_mostly; static void s3_init_wr_tab(unsigned int wr_len) @@ -485,7 +482,7 @@ static void s3_init_wr_tab(unsigned int wr_len) static inline void reset_wr_list(struct s3_conn *c3cn) { - c3cn->wr_pending_head = NULL; + c3cn->wr_pending_head = c3cn->wr_pending_tail = NULL; } /* @@ -496,7 +493,7 @@ static inline void reset_wr_list(struct s3_conn *c3cn) static inline void enqueue_wr(struct s3_conn *c3cn, struct sk_buff *skb) { - skb_wr_data(skb) = NULL; + skb_tx_wr_next(skb) = NULL; /* * We want to take an extra reference since both us and the driver @@ -509,10 +506,22 @@ static inline void enqueue_wr(struct s3_conn *c3cn, if (!c3cn->wr_pending_head) c3cn->wr_pending_head = skb; else - skb_wr_data(skb) = skb; + skb_tx_wr_next(c3cn->wr_pending_tail) = skb; c3cn->wr_pending_tail = skb; } +static int count_pending_wrs(struct s3_conn *c3cn) +{ + int n = 0; + const struct sk_buff *skb = c3cn->wr_pending_head; + + while (skb) { + n += skb->csum; + skb = skb_tx_wr_next(skb); + } + return n; +} + static inline struct sk_buff *peek_wr(const struct s3_conn *c3cn) { return c3cn->wr_pending_head; @@ -529,8 +538,8 @@ static inline struct sk_buff *dequeue_wr(struct s3_conn *c3cn) if (likely(skb)) { /* Don't bother clearing the tail */ - c3cn->wr_pending_head = skb_wr_data(skb); - skb_wr_data(skb) = NULL; + c3cn->wr_pending_head = skb_tx_wr_next(skb); + skb_tx_wr_next(skb) = NULL; } return skb; } @@ -543,13 +552,14 @@ static void purge_wr_queue(struct s3_conn *c3cn) } static inline void make_tx_data_wr(struct s3_conn *c3cn, struct sk_buff *skb, - int len) + int len, int req_completion) { struct tx_data_wr *req; skb_reset_transport_header(skb); req = (struct tx_data_wr *)__skb_push(skb, sizeof(*req)); - req->wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_TX_DATA)); + req->wr_hi = htonl(V_WR_OP(FW_WROPCODE_OFLD_TX_DATA) | + (req_completion ? F_WR_COMPL : 0)); req->wr_lo = htonl(V_WR_TID(c3cn->tid)); req->sndseq = htonl(c3cn->snd_nxt); /* len includes the length of any HW ULP additions */ @@ -592,7 +602,7 @@ static int c3cn_push_tx_frames(struct s3_conn *c3cn, int req_completion) if (unlikely(c3cn->state == C3CN_STATE_CONNECTING || c3cn->state == C3CN_STATE_CLOSE_WAIT_1 || - c3cn->state == C3CN_STATE_ABORTING)) { + c3cn->state >= C3CN_STATE_ABORTING)) { c3cn_tx_debug("c3cn 0x%p, in closing state %u.\n", c3cn, c3cn->state); return 0; @@ -615,7 +625,7 @@ static int c3cn_push_tx_frames(struct s3_conn *c3cn, int req_completion) if (c3cn->wr_avail < wrs_needed) { c3cn_tx_debug("c3cn 0x%p, skb len %u/%u, frag %u, " "wr %d < %u.\n", - c3cn, skb->len, skb->datalen, frags, + c3cn, skb->len, skb->data_len, frags, wrs_needed, c3cn->wr_avail); break; } @@ -627,20 +637,24 @@ static int c3cn_push_tx_frames(struct s3_conn *c3cn, int req_completion) c3cn->wr_unacked += wrs_needed; enqueue_wr(c3cn, skb); - if (likely(CXGB3_SKB_CB(skb)->flags & C3CB_FLAG_NEED_HDR)) { - len += ulp_extra_len(skb); - make_tx_data_wr(c3cn, skb, len); - c3cn->snd_nxt += len; - if ((req_completion - && c3cn->wr_unacked == wrs_needed) - || (CXGB3_SKB_CB(skb)->flags & C3CB_FLAG_COMPL) - || c3cn->wr_unacked >= c3cn->wr_max / 2) { - struct work_request_hdr *wr = cplhdr(skb); + c3cn_tx_debug("c3cn 0x%p, enqueue, skb len %u/%u, frag %u, " + "wr %d, left %u, unack %u.\n", + c3cn, skb->len, skb->data_len, frags, + wrs_needed, c3cn->wr_avail, c3cn->wr_unacked); + - wr->wr_hi |= htonl(F_WR_COMPL); + if (likely(skb_flags(skb) & C3CB_FLAG_NEED_HDR)) { + if ((req_completion && + c3cn->wr_unacked == wrs_needed) || + (skb_flags(skb) & C3CB_FLAG_COMPL) || + c3cn->wr_unacked >= c3cn->wr_max / 2) { + req_completion = 1; c3cn->wr_unacked = 0; } - CXGB3_SKB_CB(skb)->flags &= ~C3CB_FLAG_NEED_HDR; + len += ulp_extra_len(skb); + make_tx_data_wr(c3cn, skb, len, req_completion); + c3cn->snd_nxt += len; + skb_flags(skb) &= ~C3CB_FLAG_NEED_HDR; } total_size += skb->truesize; @@ -735,8 +749,11 @@ static void process_act_establish(struct s3_conn *c3cn, struct sk_buff *skb) if (unlikely(c3cn_flag(c3cn, C3CN_ACTIVE_CLOSE_NEEDED))) /* upper layer has requested closing */ send_abort_req(c3cn); - else if (c3cn_push_tx_frames(c3cn, 1)) + else { + if (skb_queue_len(&c3cn->write_queue)) + c3cn_push_tx_frames(c3cn, 1); cxgb3i_conn_tx_open(c3cn); + } } static int do_act_establish(struct t3cdev *cdev, struct sk_buff *skb, @@ -1082,8 +1099,8 @@ static void process_rx_iscsi_hdr(struct s3_conn *c3cn, struct sk_buff *skb) return; } - CXGB3_SKB_CB(skb)->seq = ntohl(hdr_cpl->seq); - CXGB3_SKB_CB(skb)->flags = 0; + skb_tcp_seq(skb) = ntohl(hdr_cpl->seq); + skb_flags(skb) = 0; skb_reset_transport_header(skb); __skb_pull(skb, sizeof(struct cpl_iscsi_hdr)); @@ -1103,12 +1120,12 @@ static void process_rx_iscsi_hdr(struct s3_conn *c3cn, struct sk_buff *skb) goto abort_conn; skb_ulp_mode(skb) = ULP2_FLAG_DATA_READY; - skb_ulp_pdulen(skb) = ntohs(ddp_cpl.len); - skb_ulp_ddigest(skb) = ntohl(ddp_cpl.ulp_crc); + skb_rx_pdulen(skb) = ntohs(ddp_cpl.len); + skb_rx_ddigest(skb) = ntohl(ddp_cpl.ulp_crc); status = ntohl(ddp_cpl.ddp_status); c3cn_rx_debug("rx skb 0x%p, len %u, pdulen %u, ddp status 0x%x.\n", - skb, skb->len, skb_ulp_pdulen(skb), status); + skb, skb->len, skb_rx_pdulen(skb), status); if (status & (1 << RX_DDP_STATUS_HCRC_SHIFT)) skb_ulp_mode(skb) |= ULP2_FLAG_HCRC_ERROR; @@ -1126,7 +1143,7 @@ static void process_rx_iscsi_hdr(struct s3_conn *c3cn, struct sk_buff *skb) } else if (status & (1 << RX_DDP_STATUS_DDP_SHIFT)) skb_ulp_mode(skb) |= ULP2_FLAG_DATA_DDPED; - c3cn->rcv_nxt = ntohl(ddp_cpl.seq) + skb_ulp_pdulen(skb); + c3cn->rcv_nxt = ntohl(ddp_cpl.seq) + skb_rx_pdulen(skb); __pskb_trim(skb, len); __skb_queue_tail(&c3cn->receive_queue, skb); cxgb3i_conn_pdu_ready(c3cn); @@ -1151,12 +1168,27 @@ static int do_iscsi_hdr(struct t3cdev *t3dev, struct sk_buff *skb, void *ctx) * Process an acknowledgment of WR completion. Advance snd_una and send the * next batch of work requests from the write queue. */ +static void check_wr_invariants(struct s3_conn *c3cn) +{ + int pending = count_pending_wrs(c3cn); + + if (unlikely(c3cn->wr_avail + pending != c3cn->wr_max)) + cxgb3i_log_error("TID %u: credit imbalance: avail %u, " + "pending %u, total should be %u\n", + c3cn->tid, c3cn->wr_avail, pending, + c3cn->wr_max); +} + static void process_wr_ack(struct s3_conn *c3cn, struct sk_buff *skb) { struct cpl_wr_ack *hdr = cplhdr(skb); unsigned int credits = ntohs(hdr->credits); u32 snd_una = ntohl(hdr->snd_una); + c3cn_tx_debug("%u WR credits, avail %u, unack %u, TID %u, state %u.\n", + credits, c3cn->wr_avail, c3cn->wr_unacked, + c3cn->tid, c3cn->state); + c3cn->wr_avail += credits; if (c3cn->wr_unacked > c3cn->wr_max - c3cn->wr_avail) c3cn->wr_unacked = c3cn->wr_max - c3cn->wr_avail; @@ -1171,6 +1203,17 @@ static void process_wr_ack(struct s3_conn *c3cn, struct sk_buff *skb) break; } if (unlikely(credits < p->csum)) { + struct tx_data_wr *w = cplhdr(p); + cxgb3i_log_error("TID %u got %u WR credits need %u, " + "len %u, main body %u, frags %u, " + "seq # %u, ACK una %u, ACK nxt %u, " + "WR_AVAIL %u, WRs pending %u\n", + c3cn->tid, credits, p->csum, p->len, + p->len - p->data_len, + skb_shinfo(p)->nr_frags, + ntohl(w->sndseq), snd_una, + ntohl(hdr->snd_nxt), c3cn->wr_avail, + count_pending_wrs(c3cn) - credits); p->csum -= credits; break; } else { @@ -1180,15 +1223,24 @@ static void process_wr_ack(struct s3_conn *c3cn, struct sk_buff *skb) } } - if (unlikely(before(snd_una, c3cn->snd_una))) + check_wr_invariants(c3cn); + + if (unlikely(before(snd_una, c3cn->snd_una))) { + cxgb3i_log_error("TID %u, unexpected sequence # %u in WR_ACK " + "snd_una %u\n", + c3cn->tid, snd_una, c3cn->snd_una); goto out_free; + } if (c3cn->snd_una != snd_una) { c3cn->snd_una = snd_una; dst_confirm(c3cn->dst_cache); } - if (skb_queue_len(&c3cn->write_queue) && c3cn_push_tx_frames(c3cn, 0)) + if (skb_queue_len(&c3cn->write_queue)) { + if (c3cn_push_tx_frames(c3cn, 0)) + cxgb3i_conn_tx_open(c3cn); + } else cxgb3i_conn_tx_open(c3cn); out_free: __kfree_skb(skb); @@ -1452,7 +1504,7 @@ static void init_offload_conn(struct s3_conn *c3cn, struct dst_entry *dst) { BUG_ON(c3cn->cdev != cdev); - c3cn->wr_max = c3cn->wr_avail = T3C_DATA(cdev)->max_wrs; + c3cn->wr_max = c3cn->wr_avail = T3C_DATA(cdev)->max_wrs - 1; c3cn->wr_unacked = 0; c3cn->mss_idx = select_mss(c3cn, dst_mtu(dst)); @@ -1671,9 +1723,17 @@ int cxgb3i_c3cn_send_pdus(struct s3_conn *c3cn, struct sk_buff *skb) goto out_err; } - err = -EPIPE; if (c3cn->err) { c3cn_tx_debug("c3cn 0x%p, err %d.\n", c3cn, c3cn->err); + err = -EPIPE; + goto out_err; + } + + if (c3cn->write_seq - c3cn->snd_una >= cxgb3_snd_win) { + c3cn_tx_debug("c3cn 0x%p, snd %u - %u > %u.\n", + c3cn, c3cn->write_seq, c3cn->snd_una, + cxgb3_snd_win); + err = -EAGAIN; goto out_err; } diff --git a/drivers/scsi/cxgb3i/cxgb3i_offload.h b/drivers/scsi/cxgb3i/cxgb3i_offload.h index d23156907ff..df1eae0ee4b 100644 --- a/drivers/scsi/cxgb3i/cxgb3i_offload.h +++ b/drivers/scsi/cxgb3i/cxgb3i_offload.h @@ -178,25 +178,33 @@ void cxgb3i_c3cn_release(struct s3_conn *); * @flag: see C3CB_FLAG_* below * @ulp_mode: ULP mode/submode of sk_buff * @seq: tcp sequence number - * @ddigest: pdu data digest - * @pdulen: recovered pdu length - * @wr_data: scratch area for tx wr */ +struct cxgb3_skb_rx_cb { + __u32 ddigest; /* data digest */ + __u32 pdulen; /* recovered pdu length */ +}; + +struct cxgb3_skb_tx_cb { + struct sk_buff *wr_next; /* next wr */ +}; + struct cxgb3_skb_cb { __u8 flags; __u8 ulp_mode; __u32 seq; - __u32 ddigest; - __u32 pdulen; - struct sk_buff *wr_data; + union { + struct cxgb3_skb_rx_cb rx; + struct cxgb3_skb_tx_cb tx; + }; }; #define CXGB3_SKB_CB(skb) ((struct cxgb3_skb_cb *)&((skb)->cb[0])) - +#define skb_flags(skb) (CXGB3_SKB_CB(skb)->flags) #define skb_ulp_mode(skb) (CXGB3_SKB_CB(skb)->ulp_mode) -#define skb_ulp_ddigest(skb) (CXGB3_SKB_CB(skb)->ddigest) -#define skb_ulp_pdulen(skb) (CXGB3_SKB_CB(skb)->pdulen) -#define skb_wr_data(skb) (CXGB3_SKB_CB(skb)->wr_data) +#define skb_tcp_seq(skb) (CXGB3_SKB_CB(skb)->seq) +#define skb_rx_ddigest(skb) (CXGB3_SKB_CB(skb)->rx.ddigest) +#define skb_rx_pdulen(skb) (CXGB3_SKB_CB(skb)->rx.pdulen) +#define skb_tx_wr_next(skb) (CXGB3_SKB_CB(skb)->tx.wr_next) enum c3cb_flags { C3CB_FLAG_NEED_HDR = 1 << 0, /* packet needs a TX_DATA_WR header */ -- 2.41.1