[src/trunk]: src/sys/dev/pci Implement a sliding interrupt delay window for T...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/758336b1129d
branches:  trunk
changeset: 533449:758336b1129d
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sun Jun 30 18:52:21 2002 +0000

description:
Implement a sliding interrupt delay window for Tx interrupts.

diffstat:

 sys/dev/pci/if_sip.c |  52 +++++++++++++++++++++++++++++++++++-----------------
 1 files changed, 35 insertions(+), 17 deletions(-)

diffs (130 lines):

diff -r 55390a673266 -r 758336b1129d sys/dev/pci/if_sip.c
--- a/sys/dev/pci/if_sip.c      Sun Jun 30 18:04:12 2002 +0000
+++ b/sys/dev/pci/if_sip.c      Sun Jun 30 18:52:21 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_sip.c,v 1.55 2002/06/30 18:04:12 thorpej Exp $      */
+/*     $NetBSD: if_sip.c,v 1.56 2002/06/30 18:52:21 thorpej Exp $      */
 
 /*-
  * Copyright (c) 2001, 2002 The NetBSD Foundation, Inc.
@@ -82,7 +82,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_sip.c,v 1.55 2002/06/30 18:04:12 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_sip.c,v 1.56 2002/06/30 18:52:21 thorpej Exp $");
 
 #include "bpfilter.h"
 
@@ -254,7 +254,9 @@
         */
        struct evcnt sc_ev_txsstall;    /* Tx stalled due to no txs */
        struct evcnt sc_ev_txdstall;    /* Tx stalled due to no txd */
-       struct evcnt sc_ev_txintr;      /* Tx interrupts */
+       struct evcnt sc_ev_txforceintr; /* Tx interrupts forced */
+       struct evcnt sc_ev_txdintr;     /* Tx descriptor interrupts */
+       struct evcnt sc_ev_txiintr;     /* Tx idle interrupts */
        struct evcnt sc_ev_rxintr;      /* Rx interrupts */
 #ifdef DP83820
        struct evcnt sc_ev_rxipsum;     /* IP checksums checked in-bound */
@@ -286,6 +288,7 @@
 
        int     sc_txfree;              /* number of free Tx descriptors */
        int     sc_txnext;              /* next ready Tx descriptor */
+       int     sc_txwin;               /* Tx descriptors since last intr */
 
        struct sip_txsq sc_txfreeq;     /* free Tx descsofts */
        struct sip_txsq sc_txdirtyq;    /* dirty Tx descsofts */
@@ -936,8 +939,12 @@
            NULL, sc->sc_dev.dv_xname, "txsstall");
        evcnt_attach_dynamic(&sc->sc_ev_txdstall, EVCNT_TYPE_MISC,
            NULL, sc->sc_dev.dv_xname, "txdstall");
-       evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_INTR,
-           NULL, sc->sc_dev.dv_xname, "txintr");
+       evcnt_attach_dynamic(&sc->sc_ev_txforceintr, EVCNT_TYPE_INTR,
+           NULL, sc->sc_dev.dv_xname, "txforceintr");
+       evcnt_attach_dynamic(&sc->sc_ev_txdintr, EVCNT_TYPE_INTR,
+           NULL, sc->sc_dev.dv_xname, "txdintr");
+       evcnt_attach_dynamic(&sc->sc_ev_txiintr, EVCNT_TYPE_INTR,
+           NULL, sc->sc_dev.dv_xname, "txiintr");
        evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_INTR,
            NULL, sc->sc_dev.dv_xname, "rxintr");
 #ifdef DP83820
@@ -1193,6 +1200,17 @@
                /* Clear the MORE bit on the last segment. */
                sc->sc_txdescs[lasttx].sipd_cmdsts &= htole32(~CMDSTS_MORE);
 
+               /*
+                * If we're in the interrupt delay window, delay the
+                * interrupt.
+                */
+               if (++sc->sc_txwin >= (SIP_TXQUEUELEN * 2 / 3)) {
+                       SIP_EVCNT_INCR(&sc->sc_ev_txforceintr);
+                       sc->sc_txdescs[lasttx].sipd_cmdsts |=
+                           htole32(CMDSTS_INTR);
+                       sc->sc_txwin = 0;
+               }
+
 #ifdef DP83820
                /*
                 * If VLANs are enabled and the packet has a VLAN tag, set
@@ -1272,14 +1290,6 @@
 
        if (sc->sc_txfree != ofree) {
                /*
-                * Cause a descriptor interrupt to happen on the
-                * last packet we enqueued.
-                */
-               sc->sc_txdescs[lasttx].sipd_cmdsts |= htole32(CMDSTS_INTR);
-               SIP_CDTXSYNC(sc, lasttx, 1,
-                   BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
-
-               /*
                 * The entire packet chain is set up.  Give the
                 * first descrptor to the chip now.
                 */
@@ -1436,8 +1446,13 @@
                        }
                }
 
-               if (isr & (ISR_TXURN|ISR_TXDESC)) {
-                       SIP_EVCNT_INCR(&sc->sc_ev_txintr);
+               if (isr & (ISR_TXURN|ISR_TXDESC|ISR_TXIDLE)) {
+#ifdef SIP_EVENT_COUNTERS
+                       if (isr & ISR_TXDESC)
+                               SIP_EVCNT_INCR(&sc->sc_ev_txdintr);
+                       else if (isr & ISR_TXIDLE)
+                               SIP_EVCNT_INCR(&sc->sc_ev_txiintr);
+#endif
 
                        /* Sweep up transmit descriptors. */
                        SIP_DECL(txintr)(sc);
@@ -1563,8 +1578,10 @@
         * If there are no more pending transmissions, cancel the watchdog
         * timer.
         */
-       if (txs == NULL)
+       if (txs == NULL) {
                ifp->if_timer = 0;
+               sc->sc_txwin = 0;
+       }
 }
 
 #if defined(DP83820)
@@ -2089,6 +2106,7 @@
            BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
        sc->sc_txfree = SIP_NTXDESC;
        sc->sc_txnext = 0;
+       sc->sc_txwin = 0;
 
        /*
         * Initialize the transmit job descriptors.
@@ -2224,7 +2242,7 @@
         * Initialize the interrupt mask.
         */
        sc->sc_imr = ISR_DPERR|ISR_SSERR|ISR_RMABT|ISR_RTABT|ISR_RXSOVR|
-           ISR_TXURN|ISR_TXDESC|ISR_RXORN|ISR_RXIDLE|ISR_RXDESC;
+           ISR_TXURN|ISR_TXDESC|ISR_TXIDLE|ISR_RXORN|ISR_RXIDLE|ISR_RXDESC;
        bus_space_write_4(st, sh, SIP_IMR, sc->sc_imr);
 
        /* Set up the receive filter. */