net: ethernet: ti: cpts: optimize packet to event matching

Now the CPTS driver performs packet (skb) parsing every time when it needs
to match packet to CPTS event (including ptp_classify_raw() calls).

This patch optimizes matching process by parsing packet only once upon
arrival and stores PTP specific data in skb->cb using the same fromat as in
CPTS HW event. As result, all future matching reduces to comparing two u32
values.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 1f738bb..6efb809 100644 (file)
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -23,15 +23,13 @@
 #define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */
 
 struct cpts_skb_cb_data {
+       u32 skb_mtype_seqid;
        unsigned long tmo;
 };
 
 #define cpts_read32(c, r)      readl_relaxed(&c->reg->r)
 #define cpts_write32(c, v, r)  writel_relaxed(v, &c->reg->r)
 
-static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
-                     u16 ts_seqid, u8 ts_msgtype);
-
 static int event_expired(struct cpts_event *event)
 {
        return time_after(jiffies, event->tmo);
@@ -97,29 +95,29 @@ static void cpts_purge_txq(struct cpts *cpts)
 static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
 {
        struct sk_buff *skb, *tmp;
-       u16 seqid;
-       u8 mtype;
        bool found = false;
+       u32 mtype_seqid;
 
-       mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
-       seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
+       mtype_seqid = event->high &
+                     ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+                      (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+                      (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
 
        /* no need to grab txq.lock as access is always done under cpts->lock */
        skb_queue_walk_safe(&cpts->txq, skb, tmp) {
                struct skb_shared_hwtstamps ssh;
-               unsigned int class = ptp_classify_raw(skb);
                struct cpts_skb_cb_data *skb_cb =
                                        (struct cpts_skb_cb_data *)skb->cb;
 
-               if (cpts_match(skb, class, seqid, mtype)) {
+               if (mtype_seqid == skb_cb->skb_mtype_seqid) {
                        memset(&ssh, 0, sizeof(ssh));
                        ssh.hwtstamp = ns_to_ktime(event->timestamp);
                        skb_tstamp_tx(skb, &ssh);
                        found = true;
                        __skb_unlink(skb, &cpts->txq);
                        dev_consume_skb_any(skb);
-                       dev_dbg(cpts->dev, "match tx timestamp mtype %u seqid %04x\n",
-                               mtype, seqid);
+                       dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
+                               mtype_seqid);
                        break;
                }
 
@@ -338,12 +336,15 @@ static const struct ptp_clock_info cpts_info = {
        .do_aux_work    = cpts_overflow_check,
 };
 
-static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
-                     u16 ts_seqid, u8 ts_msgtype)
+static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
 {
-       u16 *seqid;
-       unsigned int offset = 0;
+       unsigned int ptp_class = ptp_classify_raw(skb);
        u8 *msgtype, *data = skb->data;
+       unsigned int offset = 0;
+       u16 *seqid;
+
+       if (ptp_class == PTP_CLASS_NONE)
+               return 0;
 
        if (ptp_class & PTP_CLASS_VLAN)
                offset += VLAN_HLEN;
@@ -371,22 +372,20 @@ static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
                msgtype = data + offset;
 
        seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
+       *mtype_seqid = (*msgtype & MESSAGE_TYPE_MASK) << MESSAGE_TYPE_SHIFT;
+       *mtype_seqid |= (ntohs(*seqid) & SEQUENCE_ID_MASK) << SEQUENCE_ID_SHIFT;
 
-       return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
+       return 1;
 }
 
-static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
+static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
+                       int ev_type, u32 skb_mtype_seqid)
 {
-       u64 ns = 0;
-       struct cpts_event *event;
        struct list_head *this, *next;
-       unsigned int class = ptp_classify_raw(skb);
+       struct cpts_event *event;
        unsigned long flags;
-       u16 seqid;
-       u8 mtype;
-
-       if (class == PTP_CLASS_NONE)
-               return 0;
+       u32 mtype_seqid;
+       u64 ns = 0;
 
        spin_lock_irqsave(&cpts->lock, flags);
        cpts_fifo_read(cpts, -1);
@@ -397,10 +396,13 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
                        list_add(&event->list, &cpts->pool);
                        continue;
                }
-               mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
-               seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
-               if (ev_type == event_type(event) &&
-                   cpts_match(skb, class, seqid, mtype)) {
+
+               mtype_seqid = event->high &
+                             ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
+                              (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
+                              (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
+
+               if (mtype_seqid == skb_mtype_seqid) {
                        ns = event->timestamp;
                        list_del_init(&event->list);
                        list_add(&event->list, &cpts->pool);
@@ -427,10 +429,21 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
-       u64 ns;
+       struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
        struct skb_shared_hwtstamps *ssh;
+       int ret;
+       u64 ns;
+
+       ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
+       if (!ret)
+               return;
+
+       skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
 
-       ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
+       dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
+               __func__, skb_cb->skb_mtype_seqid);
+
+       ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
        if (!ns)
                return;
        ssh = skb_hwtstamps(skb);
@@ -441,12 +454,24 @@ EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
-       u64 ns;
+       struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
        struct skb_shared_hwtstamps ssh;
+       int ret;
+       u64 ns;
 
        if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
                return;
-       ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
+
+       ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
+       if (!ret)
+               return;
+
+       skb_cb->skb_mtype_seqid |= (CPTS_EV_TX << EVENT_TYPE_SHIFT);
+
+       dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
+               __func__, skb_cb->skb_mtype_seqid);
+
+       ns = cpts_find_ts(cpts, skb, CPTS_EV_TX, skb_cb->skb_mtype_seqid);
        if (!ns)
                return;
        memset(&ssh, 0, sizeof(ssh));