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-rw-r--r--hw/arm/musicpal.c6
-rw-r--r--hw/net/etraxfs_eth.c6
-rw-r--r--hw/net/lan9118.c6
-rw-r--r--hw/net/vmxnet3.c59
-rw-r--r--hw/net/vmxnet_rx_pkt.c12
-rw-r--r--hw/net/vmxnet_rx_pkt.h11
-rw-r--r--hw/ppc/ppc.c5
-rw-r--r--hw/ppc/spapr_rtc.c8
-rw-r--r--hw/timer/mc146818rtc.c18
-rw-r--r--hw/usb/hcd-ehci.c2
-rw-r--r--include/qemu/timer.h2
-rw-r--r--net/net.c19
-rw-r--r--net/socket.c2
-rw-r--r--tests/rtl8139-test.c8
-rw-r--r--tests/test-throttle.c8
-rw-r--r--tests/wdt_ib700-test.c12
-rw-r--r--util/throttle.c4
17 files changed, 127 insertions, 61 deletions
diff --git a/hw/arm/musicpal.c b/hw/arm/musicpal.c
index a3b1314..42f66b3 100644
--- a/hw/arm/musicpal.c
+++ b/hw/arm/musicpal.c
@@ -187,11 +187,6 @@ static void eth_rx_desc_get(uint32_t addr, mv88w8618_rx_desc *desc)
le32_to_cpus(&desc->next);
}
-static int eth_can_receive(NetClientState *nc)
-{
- return 1;
-}
-
static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
mv88w8618_eth_state *s = qemu_get_nic_opaque(nc);
@@ -381,7 +376,6 @@ static void eth_cleanup(NetClientState *nc)
static NetClientInfo net_mv88w8618_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
- .can_receive = eth_can_receive,
.receive = eth_receive,
.cleanup = eth_cleanup,
};
diff --git a/hw/net/etraxfs_eth.c b/hw/net/etraxfs_eth.c
index 4773dea..d600275 100644
--- a/hw/net/etraxfs_eth.c
+++ b/hw/net/etraxfs_eth.c
@@ -520,11 +520,6 @@ static int eth_match_groupaddr(ETRAXFSEthState *eth, const unsigned char *sa)
return match;
}
-static int eth_can_receive(NetClientState *nc)
-{
- return 1;
-}
-
static ssize_t eth_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
unsigned char sa_bcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
@@ -584,7 +579,6 @@ static const MemoryRegionOps eth_ops = {
static NetClientInfo net_etraxfs_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
- .can_receive = eth_can_receive,
.receive = eth_receive,
.link_status_changed = eth_set_link,
};
diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c
index f169c38..4f0e840 100644
--- a/hw/net/lan9118.c
+++ b/hw/net/lan9118.c
@@ -461,11 +461,6 @@ static void lan9118_reset(DeviceState *d)
lan9118_reload_eeprom(s);
}
-static int lan9118_can_receive(NetClientState *nc)
-{
- return 1;
-}
-
static void rx_fifo_push(lan9118_state *s, uint32_t val)
{
int fifo_pos;
@@ -1312,7 +1307,6 @@ static const MemoryRegionOps lan9118_16bit_mem_ops = {
static NetClientInfo net_lan9118_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
- .can_receive = lan9118_can_receive,
.receive = lan9118_receive,
.link_status_changed = lan9118_set_link,
};
diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c
index 706e060..59b06b8 100644
--- a/hw/net/vmxnet3.c
+++ b/hw/net/vmxnet3.c
@@ -885,6 +885,63 @@ vmxnet3_get_next_rx_descr(VMXNET3State *s, bool is_head,
}
}
+/* In case packet was csum offloaded (either NEEDS_CSUM or DATA_VALID),
+ * the implementation always passes an RxCompDesc with a "Checksum
+ * calculated and found correct" to the OS (cnc=0 and tuc=1, see
+ * vmxnet3_rx_update_descr). This emulates the observed ESXi behavior.
+ *
+ * Therefore, if packet has the NEEDS_CSUM set, we must calculate
+ * and place a fully computed checksum into the tcp/udp header.
+ * Otherwise, the OS driver will receive a checksum-correct indication
+ * (CHECKSUM_UNNECESSARY), but with the actual tcp/udp checksum field
+ * having just the pseudo header csum value.
+ *
+ * While this is not a problem if packet is destined for local delivery,
+ * in the case the host OS performs forwarding, it will forward an
+ * incorrectly checksummed packet.
+ */
+static void vmxnet3_rx_need_csum_calculate(struct VmxnetRxPkt *pkt,
+ const void *pkt_data,
+ size_t pkt_len)
+{
+ struct virtio_net_hdr *vhdr;
+ bool isip4, isip6, istcp, isudp;
+ uint8_t *data;
+ int len;
+
+ if (!vmxnet_rx_pkt_has_virt_hdr(pkt)) {
+ return;
+ }
+
+ vhdr = vmxnet_rx_pkt_get_vhdr(pkt);
+ if (!VMXNET_FLAG_IS_SET(vhdr->flags, VIRTIO_NET_HDR_F_NEEDS_CSUM)) {
+ return;
+ }
+
+ vmxnet_rx_pkt_get_protocols(pkt, &isip4, &isip6, &isudp, &istcp);
+ if (!(isip4 || isip6) || !(istcp || isudp)) {
+ return;
+ }
+
+ vmxnet3_dump_virt_hdr(vhdr);
+
+ /* Validate packet len: csum_start + scum_offset + length of csum field */
+ if (pkt_len < (vhdr->csum_start + vhdr->csum_offset + 2)) {
+ VMW_PKPRN("packet len:%d < csum_start(%d) + csum_offset(%d) + 2, "
+ "cannot calculate checksum",
+ len, vhdr->csum_start, vhdr->csum_offset);
+ return;
+ }
+
+ data = (uint8_t *)pkt_data + vhdr->csum_start;
+ len = pkt_len - vhdr->csum_start;
+ /* Put the checksum obtained into the packet */
+ stw_be_p(data + vhdr->csum_offset, net_raw_checksum(data, len));
+
+ vhdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ vhdr->flags |= VIRTIO_NET_HDR_F_DATA_VALID;
+}
+
static void vmxnet3_rx_update_descr(struct VmxnetRxPkt *pkt,
struct Vmxnet3_RxCompDesc *rxcd)
{
@@ -1897,6 +1954,8 @@ vmxnet3_receive(NetClientState *nc, const uint8_t *buf, size_t size)
get_eth_packet_type(PKT_GET_ETH_HDR(buf)));
if (vmxnet3_rx_filter_may_indicate(s, buf, size)) {
+ vmxnet_rx_pkt_set_protocols(s->rx_pkt, buf, size);
+ vmxnet3_rx_need_csum_calculate(s->rx_pkt, buf, size);
vmxnet_rx_pkt_attach_data(s->rx_pkt, buf, size, s->rx_vlan_stripping);
bytes_indicated = vmxnet3_indicate_packet(s) ? size : -1;
if (bytes_indicated < size) {
diff --git a/hw/net/vmxnet_rx_pkt.c b/hw/net/vmxnet_rx_pkt.c
index acbca6a..aa54629 100644
--- a/hw/net/vmxnet_rx_pkt.c
+++ b/hw/net/vmxnet_rx_pkt.c
@@ -92,9 +92,6 @@ void vmxnet_rx_pkt_attach_data(struct VmxnetRxPkt *pkt, const void *data,
}
pkt->tci = tci;
-
- eth_get_protocols(data, len, &pkt->isip4, &pkt->isip6,
- &pkt->isudp, &pkt->istcp);
}
void vmxnet_rx_pkt_dump(struct VmxnetRxPkt *pkt)
@@ -131,6 +128,15 @@ size_t vmxnet_rx_pkt_get_total_len(struct VmxnetRxPkt *pkt)
return pkt->tot_len;
}
+void vmxnet_rx_pkt_set_protocols(struct VmxnetRxPkt *pkt, const void *data,
+ size_t len)
+{
+ assert(pkt);
+
+ eth_get_protocols(data, len, &pkt->isip4, &pkt->isip6,
+ &pkt->isudp, &pkt->istcp);
+}
+
void vmxnet_rx_pkt_get_protocols(struct VmxnetRxPkt *pkt,
bool *isip4, bool *isip6,
bool *isudp, bool *istcp)
diff --git a/hw/net/vmxnet_rx_pkt.h b/hw/net/vmxnet_rx_pkt.h
index 5f8352a..a425846 100644
--- a/hw/net/vmxnet_rx_pkt.h
+++ b/hw/net/vmxnet_rx_pkt.h
@@ -55,6 +55,17 @@ void vmxnet_rx_pkt_init(struct VmxnetRxPkt **pkt, bool has_virt_hdr);
size_t vmxnet_rx_pkt_get_total_len(struct VmxnetRxPkt *pkt);
/**
+ * parse and set packet analysis results
+ *
+ * @pkt: packet
+ * @data: pointer to the data buffer to be parsed
+ * @len: data length
+ *
+ */
+void vmxnet_rx_pkt_set_protocols(struct VmxnetRxPkt *pkt, const void *data,
+ size_t len);
+
+/**
* fetches packet analysis results
*
* @pkt: packet
diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index 2a4b8e1..b77e303 100644
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -873,8 +873,9 @@ static int timebase_post_load(void *opaque, int version_id)
*/
host_ns = qemu_clock_get_ns(QEMU_CLOCK_HOST);
ns_diff = MAX(0, host_ns - tb_remote->time_of_the_day_ns);
- migration_duration_ns = MIN(NSEC_PER_SEC, ns_diff);
- migration_duration_tb = muldiv64(migration_duration_ns, freq, NSEC_PER_SEC);
+ migration_duration_ns = MIN(NANOSECONDS_PER_SECOND, ns_diff);
+ migration_duration_tb = muldiv64(migration_duration_ns, freq,
+ NANOSECONDS_PER_SECOND);
guest_tb = tb_remote->guest_timebase + MIN(0, migration_duration_tb);
tb_off_adj = guest_tb - cpu_get_real_ticks();
diff --git a/hw/ppc/spapr_rtc.c b/hw/ppc/spapr_rtc.c
index d20b8f2..34b27db 100644
--- a/hw/ppc/spapr_rtc.c
+++ b/hw/ppc/spapr_rtc.c
@@ -51,7 +51,7 @@ void spapr_rtc_read(DeviceState *dev, struct tm *tm, uint32_t *ns)
assert(rtc);
guest_ns = host_ns + rtc->ns_offset;
- guest_s = guest_ns / NSEC_PER_SEC;
+ guest_s = guest_ns / NANOSECONDS_PER_SECOND;
if (tm) {
gmtime_r(&guest_s, tm);
@@ -71,7 +71,7 @@ int spapr_rtc_import_offset(DeviceState *dev, int64_t legacy_offset)
rtc = SPAPR_RTC(dev);
- rtc->ns_offset = legacy_offset * NSEC_PER_SEC;
+ rtc->ns_offset = legacy_offset * NANOSECONDS_PER_SECOND;
return 0;
}
@@ -146,7 +146,7 @@ static void rtas_set_time_of_day(PowerPCCPU *cpu, sPAPRMachineState *spapr,
host_ns = qemu_clock_get_ns(rtc_clock);
- rtc->ns_offset = (new_s * NSEC_PER_SEC) - host_ns;
+ rtc->ns_offset = (new_s * NANOSECONDS_PER_SECOND) - host_ns;
rtas_st(rets, 0, RTAS_OUT_SUCCESS);
}
@@ -168,7 +168,7 @@ static void spapr_rtc_realize(DeviceState *dev, Error **errp)
qemu_get_timedate(&tm, 0);
host_s = mktimegm(&tm);
rtc_ns = qemu_clock_get_ns(rtc_clock);
- rtc->ns_offset = host_s * NSEC_PER_SEC - rtc_ns;
+ rtc->ns_offset = host_s * NANOSECONDS_PER_SECOND - rtc_ns;
object_property_add_tm(OBJECT(rtc), "date", spapr_rtc_qom_date, NULL);
}
diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index 954c34d..a9f0efd 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -56,7 +56,7 @@
#define RTC_REINJECT_ON_ACK_COUNT 20
#define RTC_CLOCK_RATE 32768
-#define UIP_HOLD_LENGTH (8 * NSEC_PER_SEC / 32768)
+#define UIP_HOLD_LENGTH (8 * NANOSECONDS_PER_SECOND / 32768)
#define MC146818_RTC(obj) OBJECT_CHECK(RTCState, (obj), TYPE_MC146818_RTC)
@@ -105,7 +105,7 @@ static uint64_t get_guest_rtc_ns(RTCState *s)
uint64_t guest_rtc;
uint64_t guest_clock = qemu_clock_get_ns(rtc_clock);
- guest_rtc = s->base_rtc * NSEC_PER_SEC
+ guest_rtc = s->base_rtc * NANOSECONDS_PER_SECOND
+ guest_clock - s->last_update + s->offset;
return guest_rtc;
}
@@ -231,16 +231,17 @@ static void check_update_timer(RTCState *s)
return;
}
- guest_nsec = get_guest_rtc_ns(s) % NSEC_PER_SEC;
+ guest_nsec = get_guest_rtc_ns(s) % NANOSECONDS_PER_SECOND;
/* if UF is clear, reprogram to next second */
next_update_time = qemu_clock_get_ns(rtc_clock)
- + NSEC_PER_SEC - guest_nsec;
+ + NANOSECONDS_PER_SECOND - guest_nsec;
/* Compute time of next alarm. One second is already accounted
* for in next_update_time.
*/
next_alarm_sec = get_next_alarm(s);
- s->next_alarm_time = next_update_time + (next_alarm_sec - 1) * NSEC_PER_SEC;
+ s->next_alarm_time = next_update_time +
+ (next_alarm_sec - 1) * NANOSECONDS_PER_SECOND;
if (s->cmos_data[RTC_REG_C] & REG_C_UF) {
/* UF is set, but AF is clear. Program the timer to target
@@ -456,7 +457,7 @@ static void cmos_ioport_write(void *opaque, hwaddr addr,
/* if disabling set mode, update the time */
if ((s->cmos_data[RTC_REG_B] & REG_B_SET) &&
(s->cmos_data[RTC_REG_A] & 0x70) <= 0x20) {
- s->offset = get_guest_rtc_ns(s) % NSEC_PER_SEC;
+ s->offset = get_guest_rtc_ns(s) % NANOSECONDS_PER_SECOND;
rtc_set_time(s);
}
}
@@ -580,7 +581,7 @@ static void rtc_update_time(RTCState *s)
int64_t guest_nsec;
guest_nsec = get_guest_rtc_ns(s);
- guest_sec = guest_nsec / NSEC_PER_SEC;
+ guest_sec = guest_nsec / NANOSECONDS_PER_SECOND;
gmtime_r(&guest_sec, &ret);
/* Is SET flag of Register B disabled? */
@@ -608,7 +609,8 @@ static int update_in_progress(RTCState *s)
guest_nsec = get_guest_rtc_ns(s);
/* UIP bit will be set at last 244us of every second. */
- if ((guest_nsec % NSEC_PER_SEC) >= (NSEC_PER_SEC - UIP_HOLD_LENGTH)) {
+ if ((guest_nsec % NANOSECONDS_PER_SECOND) >=
+ (NANOSECONDS_PER_SECOND - UIP_HOLD_LENGTH)) {
return 1;
}
return 0;
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index d7cd40b..64a54c6 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -32,7 +32,7 @@
#include "trace.h"
#define FRAME_TIMER_FREQ 1000
-#define FRAME_TIMER_NS (NSEC_PER_SEC / FRAME_TIMER_FREQ)
+#define FRAME_TIMER_NS (NANOSECONDS_PER_SECOND / FRAME_TIMER_FREQ)
#define UFRAME_TIMER_NS (FRAME_TIMER_NS / 8)
#define NB_MAXINTRATE 8 // Max rate at which controller issues ints
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index 4dda20b..5923d60 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -5,7 +5,7 @@
#include "qemu-common.h"
#include "qemu/notify.h"
-#define NSEC_PER_SEC 1000000000LL
+#define NANOSECONDS_PER_SECOND 1000000000LL
/* timers */
diff --git a/net/net.c b/net/net.c
index 6ff7fec..28a5597 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1257,14 +1257,19 @@ void qmp_set_link(const char *name, bool up, Error **errp)
static void net_vm_change_state_handler(void *opaque, int running,
RunState state)
{
- /* Complete all queued packets, to guarantee we don't modify
- * state later when VM is not running.
- */
- if (!running) {
- NetClientState *nc;
- NetClientState *tmp;
+ NetClientState *nc;
+ NetClientState *tmp;
- QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
+ QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
+ if (running) {
+ /* Flush queued packets and wake up backends. */
+ if (nc->peer && qemu_can_send_packet(nc)) {
+ qemu_flush_queued_packets(nc->peer);
+ }
+ } else {
+ /* Complete all queued packets, to guarantee we don't modify
+ * state later when VM is not running.
+ */
qemu_flush_or_purge_queued_packets(nc, true);
}
}
diff --git a/net/socket.c b/net/socket.c
index c752696..b1e3b1c 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -213,7 +213,7 @@ static void net_socket_send(void *opaque)
if (s->index >= s->packet_len) {
s->index = 0;
s->state = 0;
- if (qemu_send_packet_async(&s->nc, s->buf, size,
+ if (qemu_send_packet_async(&s->nc, s->buf, s->packet_len,
net_socket_send_completed) == 0) {
net_socket_read_poll(s, false);
break;
diff --git a/tests/rtl8139-test.c b/tests/rtl8139-test.c
index 3bff0e3..e749be3 100644
--- a/tests/rtl8139-test.c
+++ b/tests/rtl8139-test.c
@@ -86,7 +86,7 @@ static void test_timer(void)
fatal("time too big %u\n", curr);
}
for (cnt = 0; ; ) {
- clock_step(1 * NSEC_PER_SEC);
+ clock_step(1 * NANOSECONDS_PER_SECOND);
prev = curr;
curr = in_Timer();
@@ -125,7 +125,7 @@ static void test_timer(void)
out_IntrStatus(0x4000);
curr = in_Timer();
out_TimerInt(curr + 0.5 * CLK);
- clock_step(1 * NSEC_PER_SEC);
+ clock_step(1 * NANOSECONDS_PER_SECOND);
out_Timer(0);
if ((in_IntrStatus() & 0x4000) == 0) {
fatal("we should have an interrupt here!\n");
@@ -137,7 +137,7 @@ static void test_timer(void)
out_IntrStatus(0x4000);
curr = in_Timer();
out_TimerInt(curr + 0.5 * CLK);
- clock_step(1 * NSEC_PER_SEC);
+ clock_step(1 * NANOSECONDS_PER_SECOND);
out_TimerInt(0);
if ((in_IntrStatus() & 0x4000) == 0) {
fatal("we should have an interrupt here!\n");
@@ -148,7 +148,7 @@ static void test_timer(void)
next = curr + 5.0 * CLK;
out_TimerInt(next);
for (cnt = 0; ; ) {
- clock_step(1 * NSEC_PER_SEC);
+ clock_step(1 * NANOSECONDS_PER_SECOND);
prev = curr;
curr = in_Timer();
diff = (curr-prev) & 0xffffffffu;
diff --git a/tests/test-throttle.c b/tests/test-throttle.c
index 33b6b95..0168445 100644
--- a/tests/test-throttle.c
+++ b/tests/test-throttle.c
@@ -40,19 +40,19 @@ static void test_leak_bucket(void)
bkt.level = 1.5;
/* leak an op work of time */
- throttle_leak_bucket(&bkt, NSEC_PER_SEC / 150);
+ throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
g_assert(bkt.avg == 150);
g_assert(bkt.max == 15);
g_assert(double_cmp(bkt.level, 0.5));
/* leak again emptying the bucket */
- throttle_leak_bucket(&bkt, NSEC_PER_SEC / 150);
+ throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
g_assert(bkt.avg == 150);
g_assert(bkt.max == 15);
g_assert(double_cmp(bkt.level, 0));
/* check that the bucket level won't go lower */
- throttle_leak_bucket(&bkt, NSEC_PER_SEC / 150);
+ throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
g_assert(bkt.avg == 150);
g_assert(bkt.max == 15);
g_assert(double_cmp(bkt.level, 0));
@@ -90,7 +90,7 @@ static void test_compute_wait(void)
bkt.level = 15.5;
wait = throttle_compute_wait(&bkt);
/* time required to do half an operation */
- result = (int64_t) NSEC_PER_SEC / 150 / 2;
+ result = (int64_t) NANOSECONDS_PER_SECOND / 150 / 2;
g_assert(wait == result);
}
diff --git a/tests/wdt_ib700-test.c b/tests/wdt_ib700-test.c
index 10a5472..82ca597 100644
--- a/tests/wdt_ib700-test.c
+++ b/tests/wdt_ib700-test.c
@@ -40,29 +40,29 @@ static QDict *qmp_get_event(const char *name)
static QDict *ib700_program_and_wait(QTestState *s)
{
- clock_step(NSEC_PER_SEC * 40);
+ clock_step(NANOSECONDS_PER_SECOND * 40);
qmp_check_no_event();
/* 2 second limit */
outb(0x443, 14);
/* Ping */
- clock_step(NSEC_PER_SEC);
+ clock_step(NANOSECONDS_PER_SECOND);
qmp_check_no_event();
outb(0x443, 14);
/* Disable */
- clock_step(NSEC_PER_SEC);
+ clock_step(NANOSECONDS_PER_SECOND);
qmp_check_no_event();
outb(0x441, 1);
- clock_step(3 * NSEC_PER_SEC);
+ clock_step(3 * NANOSECONDS_PER_SECOND);
qmp_check_no_event();
/* Enable and let it fire */
outb(0x443, 13);
- clock_step(3 * NSEC_PER_SEC);
+ clock_step(3 * NANOSECONDS_PER_SECOND);
qmp_check_no_event();
- clock_step(2 * NSEC_PER_SEC);
+ clock_step(2 * NANOSECONDS_PER_SECOND);
return qmp_get_event("WATCHDOG");
}
diff --git a/util/throttle.c b/util/throttle.c
index ec70476..706c131 100644
--- a/util/throttle.c
+++ b/util/throttle.c
@@ -36,7 +36,7 @@ void throttle_leak_bucket(LeakyBucket *bkt, int64_t delta_ns)
double leak;
/* compute how much to leak */
- leak = (bkt->avg * (double) delta_ns) / NSEC_PER_SEC;
+ leak = (bkt->avg * (double) delta_ns) / NANOSECONDS_PER_SECOND;
/* make the bucket leak */
bkt->level = MAX(bkt->level - leak, 0);
@@ -72,7 +72,7 @@ static void throttle_do_leak(ThrottleState *ts, int64_t now)
*/
static int64_t throttle_do_compute_wait(double limit, double extra)
{
- double wait = extra * NSEC_PER_SEC;
+ double wait = extra * NANOSECONDS_PER_SECOND;
wait /= limit;
return wait;
}