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-rw-r--r--sys/amd64/amd64/trap.c10
-rw-r--r--sys/conf/files.i3861
-rw-r--r--sys/conf/options.i3865
-rw-r--r--sys/dev/dc/if_dc.c83
-rw-r--r--sys/dev/dc/if_dcreg.h7
-rw-r--r--sys/dev/fxp/if_fxp.c61
-rw-r--r--sys/dev/fxp/if_fxpvar.h4
-rw-r--r--sys/i386/i386/trap.c10
-rw-r--r--sys/kern/kern_clock.c12
-rw-r--r--sys/kern/kern_intr.c14
-rw-r--r--sys/kern/kern_poll.c422
-rw-r--r--sys/net/if.h9
-rw-r--r--sys/net/if_var.h9
-rw-r--r--sys/net/netisr.h1
-rw-r--r--sys/pci/if_dc.c83
-rw-r--r--sys/pci/if_dcreg.h7
-rw-r--r--sys/pci/if_sis.c78
-rw-r--r--sys/pci/if_sisreg.h3
18 files changed, 816 insertions, 3 deletions
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index 23ad3fc..51c4c79 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -162,6 +162,11 @@ SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
extern char *syscallnames[];
#endif
+#ifdef DEVICE_POLLING
+extern u_int32_t poll_in_trap;
+extern int ether_poll __P((int count));
+#endif /* DEVICE_POLLING */
+
/*
* Exception, fault, and trap interface to the FreeBSD kernel.
* This common code is called from assembly language IDT gate entry
@@ -239,6 +244,11 @@ trap(frame)
trap_fatal(&frame, eva);
}
+#ifdef DEVICE_POLLING
+ if (poll_in_trap)
+ ether_poll(poll_in_trap);
+#endif /* DEVICE_POLLING */
+
if ((ISPL(frame.tf_cs) == SEL_UPL) ||
((frame.tf_eflags & PSL_VM) && !in_vm86call)) {
/* user trap */
diff --git a/sys/conf/files.i386 b/sys/conf/files.i386
index 4b827e3..ea9c666 100644
--- a/sys/conf/files.i386
+++ b/sys/conf/files.i386
@@ -383,6 +383,7 @@ isa/syscons_isa.c optional sc
isa/vga_isa.c optional vga
kern/imgact_aout.c standard
kern/imgact_gzip.c optional gzip
+kern/kern_poll.c optional device_polling
kern/link_aout.c standard
kern/md4c.c optional netsmb
kern/subr_diskmbr.c standard
diff --git a/sys/conf/options.i386 b/sys/conf/options.i386
index 588171a..2bb269f 100644
--- a/sys/conf/options.i386
+++ b/sys/conf/options.i386
@@ -210,5 +210,10 @@ NETSMBCRYPTO opt_netsmb.h
SMBFS
# -------------------------------
+# Polling device handling
+# -------------------------------
+DEVICE_POLLING opt_global.h
+
+# -------------------------------
# EOF
# -------------------------------
diff --git a/sys/dev/dc/if_dc.c b/sys/dev/dc/if_dc.c
index 139983b..caee9d0 100644
--- a/sys/dev/dc/if_dc.c
+++ b/sys/dev/dc/if_dc.c
@@ -2473,6 +2473,13 @@ static void dc_rxeof(sc)
while(!(sc->dc_ldata->dc_rx_list[i].dc_status & DC_RXSTAT_OWN)) {
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING) {
+ if (sc->rxcycles <= 0)
+ break;
+ sc->rxcycles--;
+ }
+#endif /* DEVICE_POLLING */
cur_rx = &sc->dc_ldata->dc_rx_list[i];
rxstat = cur_rx->dc_status;
m = sc->dc_cdata.dc_rx_chain[i];
@@ -2786,6 +2793,60 @@ static void dc_tx_underrun(sc)
return;
}
+#ifdef DEVICE_POLLING
+static poll_handler_t dc_poll;
+
+static void
+dc_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
+{
+ struct dc_softc *sc = ifp->if_softc;
+
+ if (cmd == POLL_DEREGISTER) { /* final call, enable interrupts */
+ /* Re-enable interrupts. */
+ CSR_WRITE_4(sc, DC_IMR, DC_INTRS);
+ return;
+ }
+ sc->rxcycles = count;
+ dc_rxeof(sc);
+ dc_txeof(sc);
+ if (ifp->if_snd.ifq_head != NULL && !(ifp->if_flags & IFF_OACTIVE))
+ dc_start(ifp);
+
+ if (cmd == POLL_AND_CHECK_STATUS) { /* also check status register */
+ u_int32_t status;
+
+ status = CSR_READ_4(sc, DC_ISR);
+ status &= (DC_ISR_RX_WATDOGTIMEO|DC_ISR_RX_NOBUF|
+ DC_ISR_TX_NOBUF|DC_ISR_TX_IDLE|DC_ISR_TX_UNDERRUN|
+ DC_ISR_BUS_ERR);
+ if (!status)
+ return ;
+ /* ack what we have */
+ CSR_WRITE_4(sc, DC_ISR, status);
+
+ if (status & (DC_ISR_RX_WATDOGTIMEO|DC_ISR_RX_NOBUF) ) {
+ u_int32_t r = CSR_READ_4(sc, DC_FRAMESDISCARDED);
+ ifp->if_ierrors += (r & 0xffff) + ((r >> 17) & 0x7ff);
+
+ if (dc_rx_resync(sc))
+ dc_rxeof(sc);
+ }
+ /* restart transmit unit if necessary */
+ if (status & DC_ISR_TX_IDLE && sc->dc_cdata.dc_tx_cnt)
+ CSR_WRITE_4(sc, DC_TXSTART, 0xFFFFFFFF);
+
+ if (status & DC_ISR_TX_UNDERRUN)
+ dc_tx_underrun(sc);
+
+ if (status & DC_ISR_BUS_ERR) {
+ printf("dc_poll: dc%d bus error\n", sc->dc_unit);
+ dc_reset(sc);
+ dc_init(sc);
+ }
+ }
+}
+#endif /* DEVICE_POLLING */
+
static void dc_intr(arg)
void *arg;
{
@@ -2800,6 +2861,14 @@ static void dc_intr(arg)
DC_LOCK(sc);
ifp = &sc->arpcom.ac_if;
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING)
+ goto done;
+ if (ether_poll_register(dc_poll, ifp)) { /* ok, disable interrupts */
+ CSR_WRITE_4(sc, DC_IMR, 0x00000000);
+ goto done;
+ }
+#endif /* DEVICE_POLLING */
/* Suppress unwanted interrupts */
if (!(ifp->if_flags & IFF_UP)) {
@@ -2864,6 +2933,7 @@ static void dc_intr(arg)
if (ifp->if_snd.ifq_head != NULL)
dc_start(ifp);
+done:
DC_UNLOCK(sc);
return;
@@ -3163,6 +3233,16 @@ static void dc_init(xsc)
/*
* Enable interrupts.
*/
+#ifdef DEVICE_POLLING
+ /*
+ * ... but only if we are not polling, and make sure they are off in
+ * the case of polling. Some cards (e.g. fxp) turn interrupts on
+ * after a reset.
+ */
+ if (ifp->if_ipending & IFF_POLLING)
+ CSR_WRITE_4(sc, DC_IMR, 0x00000000);
+ else
+#endif
CSR_WRITE_4(sc, DC_IMR, DC_INTRS);
CSR_WRITE_4(sc, DC_ISR, 0xFFFFFFFF);
@@ -3378,6 +3458,9 @@ static void dc_stop(sc)
callout_stop(&sc->dc_stat_ch);
ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
+#ifdef DEVICE_POLLING
+ ether_poll_deregister(ifp);
+#endif
DC_CLRBIT(sc, DC_NETCFG, (DC_NETCFG_RX_ON|DC_NETCFG_TX_ON));
CSR_WRITE_4(sc, DC_IMR, 0x00000000);
diff --git a/sys/dev/dc/if_dcreg.h b/sys/dev/dc/if_dcreg.h
index 0052d33..8980e44 100644
--- a/sys/dev/dc/if_dcreg.h
+++ b/sys/dev/dc/if_dcreg.h
@@ -453,7 +453,11 @@ struct dc_desc {
#define DC_FILTER_HASHONLY 0x10400000
#define DC_MAXFRAGS 16
+#ifdef DEVICE_POLLING
+#define DC_RX_LIST_CNT 192
+#else
#define DC_RX_LIST_CNT 64
+#endif
#define DC_TX_LIST_CNT 256
#define DC_MIN_FRAMELEN 60
#define DC_RXLEN 1536
@@ -717,6 +721,9 @@ struct dc_softc {
int dc_srm_media;
#endif
struct mtx dc_mtx;
+#ifdef DEVICE_POLLING
+ int rxcycles; /* ... when polling */
+#endif
};
diff --git a/sys/dev/fxp/if_fxp.c b/sys/dev/fxp/if_fxp.c
index 840ed87..27b7843 100644
--- a/sys/dev/fxp/if_fxp.c
+++ b/sys/dev/fxp/if_fxp.c
@@ -1141,6 +1141,38 @@ tbdinit:
}
}
+static void fxp_intr_body(struct fxp_softc *sc, u_int8_t statack, int count);
+
+#ifdef DEVICE_POLLING
+static poll_handler_t fxp_poll;
+
+static void
+fxp_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
+{
+ struct fxp_softc *sc = ifp->if_softc;
+ u_int8_t statack ;
+
+ if (cmd == POLL_DEREGISTER) { /* final call, enable interrupts */
+ CSR_WRITE_1(sc, FXP_CSR_SCB_INTRCNTL, 0);
+ return;
+ }
+ statack = FXP_SCB_STATACK_CXTNO | FXP_SCB_STATACK_CNA |
+ FXP_SCB_STATACK_FR ;
+ if (cmd == POLL_AND_CHECK_STATUS) {
+ u_int8_t tmp ;
+ tmp = CSR_READ_1(sc, FXP_CSR_SCB_STATACK);
+ if (tmp == 0xff || tmp == 0)
+ return ; /* nothing to do */
+ tmp &= ~statack ;
+ /* ack what we can */
+ if (tmp != 0)
+ CSR_WRITE_1(sc, FXP_CSR_SCB_STATACK, tmp);
+ statack |= tmp ;
+ }
+ fxp_intr_body(sc, statack, count);
+}
+#endif /* DEVICE_POLLING */
+
/*
* Process interface interrupts.
*/
@@ -1148,9 +1180,21 @@ static void
fxp_intr(void *xsc)
{
struct fxp_softc *sc = xsc;
- struct ifnet *ifp = &sc->sc_if;
u_int8_t statack;
+#ifdef DEVICE_POLLING
+ struct ifnet *ifp = &sc->sc_if;
+
+ if (ifp->if_ipending & IFF_POLLING)
+ return ;
+ if (ether_poll_register(fxp_poll, ifp)) {
+ /* disable interrupts */
+ CSR_WRITE_1(sc, FXP_CSR_SCB_INTRCNTL, FXP_SCB_INTR_DISABLE);
+ fxp_poll(ifp, 0, 1);
+ return ;
+ }
+#endif
+
if (sc->suspended) {
return;
}
@@ -1169,6 +1213,14 @@ fxp_intr(void *xsc)
* First ACK all the interrupts in this pass.
*/
CSR_WRITE_1(sc, FXP_CSR_SCB_STATACK, statack);
+ fxp_intr_body(sc, statack, -1);
+ }
+}
+
+static void
+fxp_intr_body(struct fxp_softc *sc, u_int8_t statack, int count)
+{
+ struct ifnet *ifp = &sc->sc_if;
/*
* Free any finished transmit mbuf chains.
@@ -1220,6 +1272,9 @@ rcvloop:
rfa = (struct fxp_rfa *)(m->m_ext.ext_buf +
RFA_ALIGNMENT_FUDGE);
+#ifdef DEVICE_POLLING /* loop at most count times if count >=0 */
+ if (count < 0 || count-- > 0)
+#endif
if (rfa->rfa_status & FXP_RFA_STATUS_C) {
/*
* Remove first packet from the chain.
@@ -1276,7 +1331,6 @@ rcvloop:
fxp_scb_cmd(sc, FXP_SCB_COMMAND_RU_START);
}
}
- }
}
/*
@@ -1404,6 +1458,9 @@ fxp_stop(struct fxp_softc *sc)
ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
ifp->if_timer = 0;
+#ifdef DEVICE_POLLING
+ ether_poll_deregister(ifp);
+#endif
/*
* Cancel stats updater.
*/
diff --git a/sys/dev/fxp/if_fxpvar.h b/sys/dev/fxp/if_fxpvar.h
index 23fdaa4..b2ae9b2 100644
--- a/sys/dev/fxp/if_fxpvar.h
+++ b/sys/dev/fxp/if_fxpvar.h
@@ -57,7 +57,11 @@
* Number of receive frame area buffers. These are large so chose
* wisely.
*/
+#ifdef DEVICE_POLLING
+#define FXP_NRFABUFS 192
+#else
#define FXP_NRFABUFS 64
+#endif
/*
* Maximum number of seconds that the receiver can be idle before we
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index 23ad3fc..51c4c79 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -162,6 +162,11 @@ SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
extern char *syscallnames[];
#endif
+#ifdef DEVICE_POLLING
+extern u_int32_t poll_in_trap;
+extern int ether_poll __P((int count));
+#endif /* DEVICE_POLLING */
+
/*
* Exception, fault, and trap interface to the FreeBSD kernel.
* This common code is called from assembly language IDT gate entry
@@ -239,6 +244,11 @@ trap(frame)
trap_fatal(&frame, eva);
}
+#ifdef DEVICE_POLLING
+ if (poll_in_trap)
+ ether_poll(poll_in_trap);
+#endif /* DEVICE_POLLING */
+
if ((ISPL(frame.tf_cs) == SEL_UPL) ||
((frame.tf_eflags & PSL_VM) && !in_vm86call)) {
/* user trap */
diff --git a/sys/kern/kern_clock.c b/sys/kern/kern_clock.c
index 4c2ccc0..a338dca 100644
--- a/sys/kern/kern_clock.c
+++ b/sys/kern/kern_clock.c
@@ -69,6 +69,12 @@
#include <sys/gmon.h>
#endif
+#ifdef DEVICE_POLLING
+#include <net/netisr.h> /* for NETISR_POLL */
+
+extern void ether_poll1(void);
+extern void hardclock_device_poll(void);
+#endif /* DEVICE_POLLING */
static void initclocks __P((void *dummy));
SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
@@ -140,6 +146,9 @@ initclocks(dummy)
psdiv = pscnt = 1;
cpu_initclocks();
+#ifdef DEVICE_POLLING
+ register_netisr(NETISR_POLL, ether_poll1);
+#endif
/*
* Compute profhz/stathz, and fix profhz if needed.
*/
@@ -212,6 +221,9 @@ hardclock(frame)
statclock(frame);
tc_windup();
+#ifdef DEVICE_POLLING
+ hardclock_device_poll();
+#endif /* DEVICE_POLLING */
/*
* Process callouts at a very low cpu priority, so we don't keep the
diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c
index e873c6e..88868dc 100644
--- a/sys/kern/kern_intr.c
+++ b/sys/kern/kern_intr.c
@@ -623,7 +623,16 @@ swi_net(void *dummy)
u_int bits;
int i;
+#ifdef DEVICE_POLLING
+ for (;;) {
+ int pollmore;
+#endif
bits = atomic_readandclear_int(&netisr);
+#ifdef DEVICE_POLLING
+ if (bits == 0)
+ return;
+ pollmore = bits & (1 << NETISR_POLL);
+#endif
while ((i = ffs(bits)) != 0) {
i--;
if (netisrs[i] != NULL)
@@ -632,6 +641,11 @@ swi_net(void *dummy)
printf("swi_net: unregistered isr number: %d.\n", i);
bits &= ~(1 << i);
}
+#ifdef DEVICE_POLLING
+ if (pollmore)
+ ether_pollmore();
+ }
+#endif
}
/*
diff --git a/sys/kern/kern_poll.c b/sys/kern/kern_poll.c
new file mode 100644
index 0000000..763e5cb
--- /dev/null
+++ b/sys/kern/kern_poll.c
@@ -0,0 +1,422 @@
+/*-
+ * Copyright (c) 2001 Luigi Rizzo
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/socket.h> /* needed by net/if.h */
+#include <sys/sysctl.h>
+
+#include <net/if.h> /* for IFF_* flags */
+#include <net/netisr.h> /* for NETISR_POLL */
+
+#ifdef SMP
+#error DEVICE_POLLING is not compatible with SMP
+#endif
+
+void ether_poll1(void);
+void ether_poll(int); /* polling while in trap */
+void ether_pollmore(void);
+void hardclock_device_poll(void);
+
+/*
+ * Polling support for [network] device drivers.
+ *
+ * Drivers which support this feature try to register with the
+ * polling code.
+ *
+ * If registration is successful, the driver must disable interrupts,
+ * and further I/O is performed through the handler, which is invoked
+ * (at least once per clock tick) with 3 arguments: the "arg" passed at
+ * register time (a struct ifnet pointer), a command, and a "count" limit.
+ *
+ * The command can be one of the following:
+ * POLL_ONLY: quick move of "count" packets from input/output queues.
+ * POLL_AND_CHECK_STATUS: as above, plus check status registers or do
+ * other more expensive operations. This command is issued periodically
+ * but less frequently than POLL_ONLY.
+ * POLL_DEREGISTER: deregister and return to interrupt mode.
+ *
+ * The first two commands are only issued if the interface is marked as
+ * 'IFF_UP and IFF_RUNNING', the last one only if IFF_RUNNING is set.
+ *
+ * The count limit specifies how much work the handler can do during the
+ * call -- typically this is the number of packets to be received, or
+ * transmitted, etc. (drivers are free to interpret this number, as long
+ * as the max time spent in the function grows roughly linearly with the
+ * count).
+ *
+ * Deregistration can be requested by the driver itself (typically in the
+ * *_stop() routine), or by the polling code, by invoking the handler.
+ *
+ * Polling can be globally enabled or disabled with the sysctl variable
+ * kern.polling.enable (default is 0, disabled)
+ *
+ * A second variable controls the sharing of CPU between polling/kernel
+ * network processing, and other activities (typically userlevel tasks):
+ * kern.polling.user_frac (between 0 and 100, default 50) sets the share
+ * of CPU allocated to user tasks. CPU is allocated proportionally to the
+ * shares, by dynamically adjusting the "count" (poll_burst).
+ *
+ * Other parameters can should be left to their default values.
+ * The following constraints hold
+ *
+ * 1 <= poll_each_burst <= poll_burst <= poll_burst_max
+ * 0 <= poll_in_trap <= poll_each_burst
+ * MIN_POLL_BURST_MAX <= poll_burst_max <= MAX_POLL_BURST_MAX
+ */
+
+#define MIN_POLL_BURST_MAX 10
+#define MAX_POLL_BURST_MAX 1000
+
+SYSCTL_NODE(_kern, OID_AUTO, polling, CTLFLAG_RW, 0,
+ "Device polling parameters");
+
+static u_int32_t poll_burst = 5;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, burst, CTLFLAG_RW,
+ &poll_burst, 0, "Current polling burst size");
+
+static u_int32_t poll_each_burst = 5;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, each_burst, CTLFLAG_RW,
+ &poll_each_burst, 0, "Max size of each burst");
+
+static u_int32_t poll_burst_max = 150; /* good for 100Mbit net and HZ=1000 */
+SYSCTL_ULONG(_kern_polling, OID_AUTO, burst_max, CTLFLAG_RW,
+ &poll_burst_max, 0, "Max Polling burst size");
+
+u_int32_t poll_in_trap; /* used in trap.c */
+SYSCTL_ULONG(_kern_polling, OID_AUTO, poll_in_trap, CTLFLAG_RW,
+ &poll_in_trap, 0, "Poll burst size during a trap");
+
+static u_int32_t user_frac = 50;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, user_frac, CTLFLAG_RW,
+ &user_frac, 0, "Desired user fraction of cpu time");
+
+static u_int32_t reg_frac = 20 ;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, reg_frac, CTLFLAG_RW,
+ &reg_frac, 0, "Every this many cycles poll register");
+
+static u_int32_t short_ticks;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, short_ticks, CTLFLAG_RW,
+ &short_ticks, 0, "Hardclock ticks shorter than they should be");
+
+static u_int32_t lost_polls;
+SYSCTL_ULONG(_kern_polling, OID_AUTO, lost_polls, CTLFLAG_RW,
+ &lost_polls, 0, "How many times we would have lost a poll tick");
+
+static u_int32_t poll_handlers; /* next free entry in pr[]. */
+SYSCTL_ULONG(_kern_polling, OID_AUTO, handlers, CTLFLAG_RD,
+ &poll_handlers, 0, "Number of registered poll handlers");
+
+static int polling = 0; /* global polling enable */
+SYSCTL_ULONG(_kern_polling, OID_AUTO, enable, CTLFLAG_RW,
+ &polling, 0, "Polling enabled");
+
+
+static u_int32_t poll1_active;
+static u_int32_t need_poll_again;
+
+#define POLL_LIST_LEN 128
+struct pollrec {
+ poll_handler_t *handler;
+ struct ifnet *ifp;
+};
+
+static struct pollrec pr[POLL_LIST_LEN];
+
+/*
+ * Hook from hardclock. Tries to schedule a netisr, but keeps track
+ * of lost ticks due to the previous handler taking too long.
+ * The first part of the code is just for debugging purposes, and tries
+ * to count how often hardclock ticks are shorter than they should,
+ * meaning either stray interrupts or delayed events.
+ */
+void
+hardclock_device_poll(void)
+{
+ static struct timeval prev_t, t;
+ int delta;
+
+ microuptime(&t);
+ delta = (t.tv_usec - prev_t.tv_usec) +
+ (t.tv_sec - prev_t.tv_sec)*1000000;
+ if (delta * hz < 500000)
+ short_ticks++;
+ else
+ prev_t = t;
+
+ if (poll_handlers > 0) {
+ if (poll1_active) {
+ lost_polls++;
+ need_poll_again++;
+ } else {
+ poll1_active = 1;
+ schednetisr(NETISR_POLL);
+ }
+ }
+}
+
+/*
+ * ether_poll is called from the idle loop or from the trap handler.
+ */
+void
+ether_poll(int count)
+{
+ int i;
+ int s = splimp();
+
+ mtx_lock(&Giant);
+
+ if (count > poll_each_burst)
+ count = poll_each_burst;
+ for (i = 0 ; i < poll_handlers ; i++)
+ if (pr[i].handler && (IFF_UP|IFF_RUNNING) ==
+ (pr[i].ifp->if_flags & (IFF_UP|IFF_RUNNING)) )
+ pr[i].handler(pr[i].ifp, 0, count); /* quick check */
+ mtx_unlock(&Giant);
+ splx(s);
+}
+
+/*
+ * ether_pollmore is called after other netisr's, possibly scheduling
+ * another NETISR_POLL call, or adapting the burst size for the next cycle.
+ *
+ * It is very bad to fetch large bursts of packets from a single card at once,
+ * because the burst could take a long time to be completely processed, or
+ * could saturate the intermediate queue (ipintrq or similar) leading to
+ * losses or unfairness. To reduce the problem, and also to account better for
+ * time spent in network-related processnig, we split the burst in smaller
+ * chunks of fixed size, giving control to the other netisr's between chunks.
+ * This helps in improving the fairness, reducing livelock (because we
+ * emulate more closely the "process to completion" that we have with
+ * fastforwarding) and accounting for the work performed in low level
+ * handling and forwarding.
+ */
+
+static int residual_burst = 0;
+
+static struct timeval poll_start_t;
+
+void
+ether_pollmore()
+{
+ struct timeval t;
+ int kern_load;
+ int s = splhigh();
+
+ if (residual_burst > 0) {
+ schednetisr(NETISR_POLL);
+ /* will run immediately on return, followed by netisrs */
+ splx(s);
+ return ;
+ }
+ /* here we can account time spent in netisr's in this tick */
+ microuptime(&t);
+ kern_load = (t.tv_usec - poll_start_t.tv_usec) +
+ (t.tv_sec - poll_start_t.tv_sec)*1000000; /* us */
+ kern_load = (kern_load * hz) / 10000; /* 0..100 */
+ if (kern_load > (100 - user_frac)) { /* try decrease ticks */
+ if (poll_burst > 1)
+ poll_burst--;
+ } else {
+ if (poll_burst < poll_burst_max)
+ poll_burst++;
+ }
+
+ if (need_poll_again) {
+ /*
+ * Last cycle was long and caused us to miss one or more
+ * hardclock ticks. Restart processnig again, but slightly
+ * reduce the burst size to prevent that this happens again.
+ */
+ need_poll_again--;
+ poll_burst -= (poll_burst / 8);
+ if (poll_burst < 1)
+ poll_burst = 1;
+ schednetisr(NETISR_POLL);
+ } else
+ poll1_active = 0;
+ splx(s);
+}
+
+/*
+ * ether_poll1 is called by schednetisr when appropriate, typically once
+ * per tick. It is called at splnet() so first thing to do is to upgrade to
+ * splimp(), and call all registered handlers.
+ */
+void
+ether_poll1(void)
+{
+ static int reg_frac_count;
+ int i, cycles;
+ enum poll_cmd arg = POLL_ONLY;
+ int s=splimp();
+ mtx_lock(&Giant);
+
+ if (residual_burst == 0) { /* first call in this tick */
+ microuptime(&poll_start_t);
+ /*
+ * Check that paremeters are consistent with runtime
+ * variables. Some of these tests could be done at sysctl
+ * time, but the savings would be very limited because we
+ * still have to check against reg_frac_count and
+ * poll_each_burst. So, instead of writing separate sysctl
+ * handlers, we do all here.
+ */
+
+ if (reg_frac > hz)
+ reg_frac = hz;
+ else if (reg_frac < 1)
+ reg_frac = 1;
+ if (reg_frac_count > reg_frac)
+ reg_frac_count = reg_frac - 1;
+ if (reg_frac_count-- == 0) {
+ arg = POLL_AND_CHECK_STATUS;
+ reg_frac_count = reg_frac - 1;
+ }
+ if (poll_burst_max < MIN_POLL_BURST_MAX)
+ poll_burst_max = MIN_POLL_BURST_MAX;
+ else if (poll_burst_max > MAX_POLL_BURST_MAX)
+ poll_burst_max = MAX_POLL_BURST_MAX;
+
+ if (poll_each_burst < 1)
+ poll_each_burst = 1;
+ else if (poll_each_burst > poll_burst_max)
+ poll_each_burst = poll_burst_max;
+
+ residual_burst = poll_burst;
+ }
+ cycles = (residual_burst < poll_each_burst) ?
+ residual_burst : poll_each_burst;
+ residual_burst -= cycles;
+
+ if (polling) {
+ for (i = 0 ; i < poll_handlers ; i++)
+ if (pr[i].handler && (IFF_UP|IFF_RUNNING) ==
+ (pr[i].ifp->if_flags & (IFF_UP|IFF_RUNNING)) )
+ pr[i].handler(pr[i].ifp, arg, cycles);
+ } else { /* unregister */
+ for (i = 0 ; i < poll_handlers ; i++) {
+ if (pr[i].handler &&
+ pr[i].ifp->if_flags & IFF_RUNNING) {
+ pr[i].ifp->if_ipending &= ~IFF_POLLING;
+ pr[i].handler(pr[i].ifp, POLL_DEREGISTER, 1);
+ }
+ pr[i].handler=NULL;
+ }
+ residual_burst = 0;
+ poll_handlers = 0;
+ }
+ /* on -stable, schednetisr(NETISR_POLLMORE); */
+ mtx_unlock(&Giant);
+ splx(s);
+}
+
+/*
+ * Try to register routine for polling. Returns 1 if successful
+ * (and polling should be enabled), 0 otherwise.
+ * A device is not supposed to register itself multiple times.
+ *
+ * This is called from within the *_intr() function, so we should
+ * probably not need further locking. XXX
+ */
+int
+ether_poll_register(poll_handler_t *h, struct ifnet *ifp)
+{
+ int s;
+
+ if (polling == 0) /* polling disabled, cannot register */
+ return 0;
+ if (h == NULL || ifp == NULL) /* bad arguments */
+ return 0;
+ if ( !(ifp->if_flags & IFF_UP) ) /* must be up */
+ return 0;
+ if (ifp->if_ipending & IFF_POLLING) /* already polling */
+ return 0;
+
+ s = splhigh();
+ if (poll_handlers >= POLL_LIST_LEN) {
+ /*
+ * List full, cannot register more entries.
+ * This should never happen; if it does, it is probably a
+ * broken driver trying to register multiple times. Checking
+ * this at runtime is expensive, and won't solve the problem
+ * anyways, so just report a few times and then give up.
+ */
+ static int verbose = 10 ;
+ splx(s);
+ if (verbose >0) {
+ printf("poll handlers list full, "
+ "maybe a broken driver ?\n");
+ verbose--;
+ }
+ return 0; /* no polling for you */
+ }
+
+ pr[poll_handlers].handler = h;
+ pr[poll_handlers].ifp = ifp;
+ poll_handlers++;
+ ifp->if_ipending |= IFF_POLLING;
+ splx(s);
+ return 1; /* polling enabled in next call */
+}
+
+/*
+ * Remove the interface from the list of polling ones.
+ * Normally run by *_stop().
+ * We allow it being called with IFF_POLLING clear, the
+ * call is sufficiently rare so it is preferable to save the
+ * space for the extra test in each device in exchange of one
+ * additional function call.
+ */
+int
+ether_poll_deregister(struct ifnet *ifp)
+{
+ int i;
+
+ mtx_lock(&Giant);
+ if ( !ifp || !(ifp->if_ipending & IFF_POLLING) ) {
+ mtx_unlock(&Giant);
+ return 0;
+ }
+ for (i = 0 ; i < poll_handlers ; i++)
+ if (pr[i].ifp == ifp) /* found it */
+ break;
+ ifp->if_ipending &= ~IFF_POLLING; /* found or not... */
+ if (i == poll_handlers) {
+ mtx_unlock(&Giant);
+ printf("ether_poll_deregister: ifp not found!!!\n");
+ return 0;
+ }
+ poll_handlers--;
+ if (i < poll_handlers) { /* Last entry replaces this one. */
+ pr[i].handler = pr[poll_handlers].handler;
+ pr[i].ifp = pr[poll_handlers].ifp;
+ }
+ mtx_unlock(&Giant);
+ return 1;
+}
diff --git a/sys/net/if.h b/sys/net/if.h
index 83116b9..6cc5522 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -131,6 +131,15 @@ struct if_data {
#define IFF_ALTPHYS IFF_LINK2 /* use alternate physical connection */
#define IFF_MULTICAST 0x8000 /* supports multicast */
+/*
+ * The following flag(s) ought to go in if_flags, but we cannot change
+ * struct ifnet because of binary compatibility, so we store them in
+ * if_ipending, which is not used so far.
+ * If possible, make sure the value is not conflicting with other
+ * IFF flags, so we have an easier time when we want to merge them.
+ */
+#define IFF_POLLING 0x10000 /* Interface is in polling mode. */
+
/* flags set internally only: */
#define IFF_CANTCHANGE \
(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 58d3780..dacea63 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -459,6 +459,15 @@ int if_clone_destroy __P((const char *));
#define IF_LLADDR(ifp) \
LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
+#ifdef DEVICE_POLLING
+enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
+
+typedef void poll_handler_t __P((struct ifnet *ifp,
+ enum poll_cmd cmd, int count));
+int ether_poll_register __P((poll_handler_t *h, struct ifnet *ifp));
+int ether_poll_deregister __P((struct ifnet *ifp));
+#endif /* DEVICE_POLLING */
+
#endif /* _KERNEL */
#endif /* !_NET_IF_VAR_H_ */
diff --git a/sys/net/netisr.h b/sys/net/netisr.h
index 621cf22..35e8cc1 100644
--- a/sys/net/netisr.h
+++ b/sys/net/netisr.h
@@ -52,6 +52,7 @@
* interrupt used for scheduling the network code to calls
* on the lowest level routine of each protocol.
*/
+#define NETISR_POLL 0 /* polling callback, must be first */
#define NETISR_IP 2 /* same as AF_INET */
#define NETISR_NS 6 /* same as AF_NS */
#define NETISR_ATALK 16 /* same as AF_APPLETALK */
diff --git a/sys/pci/if_dc.c b/sys/pci/if_dc.c
index 139983b..caee9d0 100644
--- a/sys/pci/if_dc.c
+++ b/sys/pci/if_dc.c
@@ -2473,6 +2473,13 @@ static void dc_rxeof(sc)
while(!(sc->dc_ldata->dc_rx_list[i].dc_status & DC_RXSTAT_OWN)) {
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING) {
+ if (sc->rxcycles <= 0)
+ break;
+ sc->rxcycles--;
+ }
+#endif /* DEVICE_POLLING */
cur_rx = &sc->dc_ldata->dc_rx_list[i];
rxstat = cur_rx->dc_status;
m = sc->dc_cdata.dc_rx_chain[i];
@@ -2786,6 +2793,60 @@ static void dc_tx_underrun(sc)
return;
}
+#ifdef DEVICE_POLLING
+static poll_handler_t dc_poll;
+
+static void
+dc_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
+{
+ struct dc_softc *sc = ifp->if_softc;
+
+ if (cmd == POLL_DEREGISTER) { /* final call, enable interrupts */
+ /* Re-enable interrupts. */
+ CSR_WRITE_4(sc, DC_IMR, DC_INTRS);
+ return;
+ }
+ sc->rxcycles = count;
+ dc_rxeof(sc);
+ dc_txeof(sc);
+ if (ifp->if_snd.ifq_head != NULL && !(ifp->if_flags & IFF_OACTIVE))
+ dc_start(ifp);
+
+ if (cmd == POLL_AND_CHECK_STATUS) { /* also check status register */
+ u_int32_t status;
+
+ status = CSR_READ_4(sc, DC_ISR);
+ status &= (DC_ISR_RX_WATDOGTIMEO|DC_ISR_RX_NOBUF|
+ DC_ISR_TX_NOBUF|DC_ISR_TX_IDLE|DC_ISR_TX_UNDERRUN|
+ DC_ISR_BUS_ERR);
+ if (!status)
+ return ;
+ /* ack what we have */
+ CSR_WRITE_4(sc, DC_ISR, status);
+
+ if (status & (DC_ISR_RX_WATDOGTIMEO|DC_ISR_RX_NOBUF) ) {
+ u_int32_t r = CSR_READ_4(sc, DC_FRAMESDISCARDED);
+ ifp->if_ierrors += (r & 0xffff) + ((r >> 17) & 0x7ff);
+
+ if (dc_rx_resync(sc))
+ dc_rxeof(sc);
+ }
+ /* restart transmit unit if necessary */
+ if (status & DC_ISR_TX_IDLE && sc->dc_cdata.dc_tx_cnt)
+ CSR_WRITE_4(sc, DC_TXSTART, 0xFFFFFFFF);
+
+ if (status & DC_ISR_TX_UNDERRUN)
+ dc_tx_underrun(sc);
+
+ if (status & DC_ISR_BUS_ERR) {
+ printf("dc_poll: dc%d bus error\n", sc->dc_unit);
+ dc_reset(sc);
+ dc_init(sc);
+ }
+ }
+}
+#endif /* DEVICE_POLLING */
+
static void dc_intr(arg)
void *arg;
{
@@ -2800,6 +2861,14 @@ static void dc_intr(arg)
DC_LOCK(sc);
ifp = &sc->arpcom.ac_if;
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING)
+ goto done;
+ if (ether_poll_register(dc_poll, ifp)) { /* ok, disable interrupts */
+ CSR_WRITE_4(sc, DC_IMR, 0x00000000);
+ goto done;
+ }
+#endif /* DEVICE_POLLING */
/* Suppress unwanted interrupts */
if (!(ifp->if_flags & IFF_UP)) {
@@ -2864,6 +2933,7 @@ static void dc_intr(arg)
if (ifp->if_snd.ifq_head != NULL)
dc_start(ifp);
+done:
DC_UNLOCK(sc);
return;
@@ -3163,6 +3233,16 @@ static void dc_init(xsc)
/*
* Enable interrupts.
*/
+#ifdef DEVICE_POLLING
+ /*
+ * ... but only if we are not polling, and make sure they are off in
+ * the case of polling. Some cards (e.g. fxp) turn interrupts on
+ * after a reset.
+ */
+ if (ifp->if_ipending & IFF_POLLING)
+ CSR_WRITE_4(sc, DC_IMR, 0x00000000);
+ else
+#endif
CSR_WRITE_4(sc, DC_IMR, DC_INTRS);
CSR_WRITE_4(sc, DC_ISR, 0xFFFFFFFF);
@@ -3378,6 +3458,9 @@ static void dc_stop(sc)
callout_stop(&sc->dc_stat_ch);
ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
+#ifdef DEVICE_POLLING
+ ether_poll_deregister(ifp);
+#endif
DC_CLRBIT(sc, DC_NETCFG, (DC_NETCFG_RX_ON|DC_NETCFG_TX_ON));
CSR_WRITE_4(sc, DC_IMR, 0x00000000);
diff --git a/sys/pci/if_dcreg.h b/sys/pci/if_dcreg.h
index 0052d33..8980e44 100644
--- a/sys/pci/if_dcreg.h
+++ b/sys/pci/if_dcreg.h
@@ -453,7 +453,11 @@ struct dc_desc {
#define DC_FILTER_HASHONLY 0x10400000
#define DC_MAXFRAGS 16
+#ifdef DEVICE_POLLING
+#define DC_RX_LIST_CNT 192
+#else
#define DC_RX_LIST_CNT 64
+#endif
#define DC_TX_LIST_CNT 256
#define DC_MIN_FRAMELEN 60
#define DC_RXLEN 1536
@@ -717,6 +721,9 @@ struct dc_softc {
int dc_srm_media;
#endif
struct mtx dc_mtx;
+#ifdef DEVICE_POLLING
+ int rxcycles; /* ... when polling */
+#endif
};
diff --git a/sys/pci/if_sis.c b/sys/pci/if_sis.c
index e74cfa0..ec7ee82 100644
--- a/sys/pci/if_sis.c
+++ b/sys/pci/if_sis.c
@@ -1273,6 +1273,13 @@ static void sis_rxeof(sc)
while(SIS_OWNDESC(&sc->sis_ldata.sis_rx_list[i])) {
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING) {
+ if (sc->rxcycles <= 0)
+ break;
+ sc->rxcycles--;
+ }
+#endif /* DEVICE_POLLING */
cur_rx = &sc->sis_ldata.sis_rx_list[i];
rxstat = cur_rx->sis_rxstat;
bus_dmamap_sync(sc->sis_tag,
@@ -1441,6 +1448,55 @@ static void sis_tick(xsc)
return;
}
+#ifdef DEVICE_POLLING
+static poll_handler_t sis_poll;
+
+static void
+sis_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
+{
+ struct sis_softc *sc = ifp->if_softc;
+ SIS_LOCK(sc);
+ if (cmd == POLL_DEREGISTER) { /* final call, enable interrupts */
+ CSR_WRITE_4(sc, SIS_IER, 1);
+ goto done;
+ }
+
+ /*
+ * On the sis, reading the status register also clears it.
+ * So before returning to intr mode we must make sure that all
+ * possible pending sources of interrupts have been served.
+ * In practice this means run to completion the *eof routines,
+ * and then call the interrupt routine
+ */
+ sc->rxcycles = count;
+ sis_rxeof(sc);
+ sis_txeof(sc);
+ if (ifp->if_snd.ifq_head != NULL)
+ sis_start(ifp);
+
+ if (sc->rxcycles > 0 || cmd == POLL_AND_CHECK_STATUS) {
+ u_int32_t status;
+
+ /* Reading the ISR register clears all interrupts. */
+ status = CSR_READ_4(sc, SIS_ISR);
+
+ if (status & (SIS_ISR_RX_ERR|SIS_ISR_RX_OFLOW))
+ sis_rxeoc(sc);
+
+ if (status & (SIS_ISR_RX_IDLE))
+ SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
+
+ if (status & SIS_ISR_SYSERR) {
+ sis_reset(sc);
+ sis_init(sc);
+ }
+ }
+done:
+ SIS_UNLOCK(sc);
+ return;
+}
+#endif /* DEVICE_POLLING */
+
static void sis_intr(arg)
void *arg;
{
@@ -1452,6 +1508,15 @@ static void sis_intr(arg)
ifp = &sc->arpcom.ac_if;
SIS_LOCK(sc);
+#ifdef DEVICE_POLLING
+ if (ifp->if_ipending & IFF_POLLING)
+ goto done;
+ if (ether_poll_register(sis_poll, ifp)) { /* ok, disable interrupts */
+ CSR_WRITE_4(sc, SIS_IER, 0);
+ goto done;
+ }
+#endif /* DEVICE_POLLING */
+
/* Supress unwanted interrupts */
if (!(ifp->if_flags & IFF_UP)) {
sis_stop(sc);
@@ -1741,6 +1806,15 @@ static void sis_init(xsc)
* Enable interrupts.
*/
CSR_WRITE_4(sc, SIS_IMR, SIS_INTRS);
+#ifdef DEVICE_POLLING
+ /*
+ * ... only enable interrupts if we are not polling, make sure
+ * they are off otherwise.
+ */
+ if (ifp->if_ipending & IFF_POLLING)
+ CSR_WRITE_4(sc, SIS_IER, 0);
+ else
+#endif /* DEVICE_POLLING */
CSR_WRITE_4(sc, SIS_IER, 1);
/* Enable receiver and transmitter. */
@@ -1910,7 +1984,9 @@ static void sis_stop(sc)
untimeout(sis_tick, sc, sc->sis_stat_ch);
ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
-
+#ifdef DEVICE_POLLING
+ ether_poll_deregister(ifp);
+#endif
CSR_WRITE_4(sc, SIS_IER, 0);
CSR_WRITE_4(sc, SIS_IMR, 0);
SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE|SIS_CSR_RX_DISABLE);
diff --git a/sys/pci/if_sisreg.h b/sys/pci/if_sisreg.h
index 7ac424f..8032175 100644
--- a/sys/pci/if_sisreg.h
+++ b/sys/pci/if_sisreg.h
@@ -418,6 +418,9 @@ struct sis_softc {
bus_dma_tag_t sis_tag;
struct sis_ring_data sis_cdata;
struct callout_handle sis_stat_ch;
+#ifdef DEVICE_POLLING
+ int rxcycles;
+#endif
struct mtx sis_mtx;
};
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