rxrpc: Keep the call timeouts as ktimes rather than jiffies

Keep that call timeouts as ktimes rather than jiffies so that they can be
expressed as functions of RTT.

Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2016-09-26 22:12:49 +01:00
parent c31410ea00
commit df0adc788a
8 changed files with 82 additions and 74 deletions

View File

@ -453,17 +453,18 @@ TRACE_EVENT(rxrpc_rtt_rx,
TRACE_EVENT(rxrpc_timer,
TP_PROTO(struct rxrpc_call *call, enum rxrpc_timer_trace why,
unsigned long now),
ktime_t now, unsigned long now_j),
TP_ARGS(call, why, now),
TP_ARGS(call, why, now, now_j),
TP_STRUCT__entry(
__field(struct rxrpc_call *, call )
__field(enum rxrpc_timer_trace, why )
__field(unsigned long, now )
__field(unsigned long, expire_at )
__field(unsigned long, ack_at )
__field(unsigned long, resend_at )
__field_struct(ktime_t, now )
__field_struct(ktime_t, expire_at )
__field_struct(ktime_t, ack_at )
__field_struct(ktime_t, resend_at )
__field(unsigned long, now_j )
__field(unsigned long, timer )
),
@ -474,17 +475,17 @@ TRACE_EVENT(rxrpc_timer,
__entry->expire_at = call->expire_at;
__entry->ack_at = call->ack_at;
__entry->resend_at = call->resend_at;
__entry->now_j = now_j;
__entry->timer = call->timer.expires;
),
TP_printk("c=%p %s now=%lx x=%ld a=%ld r=%ld t=%ld",
TP_printk("c=%p %s x=%lld a=%lld r=%lld t=%ld",
__entry->call,
rxrpc_timer_traces[__entry->why],
__entry->now,
__entry->expire_at - __entry->now,
__entry->ack_at - __entry->now,
__entry->resend_at - __entry->now,
__entry->timer - __entry->now)
ktime_to_ns(ktime_sub(__entry->expire_at, __entry->now)),
ktime_to_ns(ktime_sub(__entry->ack_at, __entry->now)),
ktime_to_ns(ktime_sub(__entry->resend_at, __entry->now)),
__entry->timer - __entry->now_j)
);
TRACE_EVENT(rxrpc_rx_lose,

View File

@ -464,9 +464,9 @@ struct rxrpc_call {
struct rxrpc_connection *conn; /* connection carrying call */
struct rxrpc_peer *peer; /* Peer record for remote address */
struct rxrpc_sock __rcu *socket; /* socket responsible */
unsigned long ack_at; /* When deferred ACK needs to happen */
unsigned long resend_at; /* When next resend needs to happen */
unsigned long expire_at; /* When the call times out */
ktime_t ack_at; /* When deferred ACK needs to happen */
ktime_t resend_at; /* When next resend needs to happen */
ktime_t expire_at; /* When the call times out */
struct timer_list timer; /* Combined event timer */
struct work_struct processor; /* Event processor */
rxrpc_notify_rx_t notify_rx; /* kernel service Rx notification function */
@ -805,7 +805,7 @@ int rxrpc_reject_call(struct rxrpc_sock *);
/*
* call_event.c
*/
void rxrpc_set_timer(struct rxrpc_call *, enum rxrpc_timer_trace);
void rxrpc_set_timer(struct rxrpc_call *, enum rxrpc_timer_trace, ktime_t);
void rxrpc_propose_ACK(struct rxrpc_call *, u8, u16, u32, bool, bool,
enum rxrpc_propose_ack_trace);
void rxrpc_process_call(struct work_struct *);

View File

@ -24,28 +24,40 @@
/*
* Set the timer
*/
void rxrpc_set_timer(struct rxrpc_call *call, enum rxrpc_timer_trace why)
void rxrpc_set_timer(struct rxrpc_call *call, enum rxrpc_timer_trace why,
ktime_t now)
{
unsigned long t, now = jiffies;
unsigned long t_j, now_j = jiffies;
ktime_t t;
read_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE) {
t = call->expire_at;
if (time_before_eq(t, now))
if (!ktime_after(t, now))
goto out;
if (time_after(call->resend_at, now) &&
time_before(call->resend_at, t))
if (ktime_after(call->resend_at, now) &&
ktime_before(call->resend_at, t))
t = call->resend_at;
if (time_after(call->ack_at, now) &&
time_before(call->ack_at, t))
if (ktime_after(call->ack_at, now) &&
ktime_before(call->ack_at, t))
t = call->ack_at;
if (call->timer.expires != t || !timer_pending(&call->timer)) {
mod_timer(&call->timer, t);
trace_rxrpc_timer(call, why, now);
t_j = nsecs_to_jiffies(ktime_to_ns(ktime_sub(t, now)));
t_j += jiffies;
/* We have to make sure that the calculated jiffies value falls
* at or after the nsec value, or we may loop ceaselessly
* because the timer times out, but we haven't reached the nsec
* timeout yet.
*/
t_j++;
if (call->timer.expires != t_j || !timer_pending(&call->timer)) {
mod_timer(&call->timer, t_j);
trace_rxrpc_timer(call, why, now, now_j);
}
}
@ -62,7 +74,8 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
enum rxrpc_propose_ack_trace why)
{
enum rxrpc_propose_ack_outcome outcome = rxrpc_propose_ack_use;
unsigned long now, ack_at, expiry = rxrpc_soft_ack_delay;
unsigned int expiry = rxrpc_soft_ack_delay;
ktime_t now, ack_at;
s8 prior = rxrpc_ack_priority[ack_reason];
/* Update DELAY, IDLE, REQUESTED and PING_RESPONSE ACK serial
@ -111,7 +124,6 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
break;
}
now = jiffies;
if (test_bit(RXRPC_CALL_EV_ACK, &call->events)) {
_debug("already scheduled");
} else if (immediate || expiry == 0) {
@ -120,11 +132,11 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
background)
rxrpc_queue_call(call);
} else {
ack_at = now + expiry;
_debug("deferred ACK %ld < %ld", expiry, call->ack_at - now);
if (time_before(ack_at, call->ack_at)) {
now = ktime_get_real();
ack_at = ktime_add_ms(now, expiry);
if (ktime_before(ack_at, call->ack_at)) {
call->ack_at = ack_at;
rxrpc_set_timer(call, rxrpc_timer_set_for_ack);
rxrpc_set_timer(call, rxrpc_timer_set_for_ack, now);
}
}
@ -157,12 +169,12 @@ static void rxrpc_congestion_timeout(struct rxrpc_call *call)
/*
* Perform retransmission of NAK'd and unack'd packets.
*/
static void rxrpc_resend(struct rxrpc_call *call)
static void rxrpc_resend(struct rxrpc_call *call, ktime_t now)
{
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
rxrpc_seq_t cursor, seq, top;
ktime_t now = ktime_get_real(), max_age, oldest, resend_at, ack_ts;
ktime_t max_age, oldest, ack_ts;
int ix;
u8 annotation, anno_type, retrans = 0, unacked = 0;
@ -212,14 +224,7 @@ static void rxrpc_resend(struct rxrpc_call *call)
ktime_to_ns(ktime_sub(skb->tstamp, max_age)));
}
resend_at = ktime_add_ms(oldest, rxrpc_resend_timeout);
call->resend_at = jiffies +
nsecs_to_jiffies(ktime_to_ns(ktime_sub(resend_at, now))) +
1; /* We have to make sure that the calculated jiffies value
* falls at or after the nsec value, or we shall loop
* ceaselessly because the timer times out, but we haven't
* reached the nsec timeout yet.
*/
call->resend_at = ktime_add_ms(oldest, rxrpc_resend_timeout);
if (unacked)
rxrpc_congestion_timeout(call);
@ -229,7 +234,7 @@ static void rxrpc_resend(struct rxrpc_call *call)
* retransmitting data.
*/
if (!retrans) {
rxrpc_set_timer(call, rxrpc_timer_set_for_resend);
rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now);
spin_unlock_bh(&call->lock);
ack_ts = ktime_sub(now, call->acks_latest_ts);
if (ktime_to_ns(ack_ts) < call->peer->rtt)
@ -301,7 +306,7 @@ void rxrpc_process_call(struct work_struct *work)
{
struct rxrpc_call *call =
container_of(work, struct rxrpc_call, processor);
unsigned long now;
ktime_t now;
rxrpc_see_call(call);
@ -320,15 +325,15 @@ recheck_state:
goto out_put;
}
now = jiffies;
if (time_after_eq(now, call->expire_at)) {
now = ktime_get_real();
if (ktime_before(call->expire_at, now)) {
rxrpc_abort_call("EXP", call, 0, RX_CALL_TIMEOUT, ETIME);
set_bit(RXRPC_CALL_EV_ABORT, &call->events);
goto recheck_state;
}
if (test_and_clear_bit(RXRPC_CALL_EV_ACK, &call->events) ||
time_after_eq(now, call->ack_at)) {
ktime_before(call->ack_at, now)) {
call->ack_at = call->expire_at;
if (call->ackr_reason) {
rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK);
@ -337,12 +342,12 @@ recheck_state:
}
if (test_and_clear_bit(RXRPC_CALL_EV_RESEND, &call->events) ||
time_after_eq(now, call->resend_at)) {
rxrpc_resend(call);
ktime_before(call->resend_at, now)) {
rxrpc_resend(call, now);
goto recheck_state;
}
rxrpc_set_timer(call, rxrpc_timer_set_for_resend);
rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now);
/* other events may have been raised since we started checking */
if (call->events && call->state < RXRPC_CALL_COMPLETE) {

View File

@ -19,11 +19,6 @@
#include <net/af_rxrpc.h>
#include "ar-internal.h"
/*
* Maximum lifetime of a call (in jiffies).
*/
unsigned int rxrpc_max_call_lifetime = 60 * HZ;
const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
[RXRPC_CALL_UNINITIALISED] = "Uninit ",
[RXRPC_CALL_CLIENT_AWAIT_CONN] = "ClWtConn",
@ -77,7 +72,8 @@ static void rxrpc_call_timer_expired(unsigned long _call)
_enter("%d", call->debug_id);
if (call->state < RXRPC_CALL_COMPLETE) {
trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
trace_rxrpc_timer(call, rxrpc_timer_expired,
ktime_get_real(), jiffies);
rxrpc_queue_call(call);
}
}
@ -207,14 +203,14 @@ static struct rxrpc_call *rxrpc_alloc_client_call(struct sockaddr_rxrpc *srx,
*/
static void rxrpc_start_call_timer(struct rxrpc_call *call)
{
unsigned long expire_at;
ktime_t now = ktime_get_real(), expire_at;
expire_at = jiffies + rxrpc_max_call_lifetime;
expire_at = ktime_add_ms(now, rxrpc_max_call_lifetime);
call->expire_at = expire_at;
call->ack_at = expire_at;
call->resend_at = expire_at;
call->timer.expires = expire_at + 1;
rxrpc_set_timer(call, rxrpc_timer_begin);
call->timer.expires = jiffies + LONG_MAX / 2;
rxrpc_set_timer(call, rxrpc_timer_begin, now);
}
/*

View File

@ -328,7 +328,8 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
call->resend_at = call->expire_at;
call->ack_at = call->expire_at;
spin_unlock_bh(&call->lock);
rxrpc_set_timer(call, rxrpc_timer_init_for_reply);
rxrpc_set_timer(call, rxrpc_timer_init_for_reply,
ktime_get_real());
}
if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags))

View File

@ -20,29 +20,34 @@
*/
unsigned int rxrpc_max_backlog __read_mostly = 10;
/*
* Maximum lifetime of a call (in mx).
*/
unsigned int rxrpc_max_call_lifetime = 60 * 1000;
/*
* How long to wait before scheduling ACK generation after seeing a
* packet with RXRPC_REQUEST_ACK set (in jiffies).
* packet with RXRPC_REQUEST_ACK set (in ms).
*/
unsigned int rxrpc_requested_ack_delay = 1;
/*
* How long to wait before scheduling an ACK with subtype DELAY (in jiffies).
* How long to wait before scheduling an ACK with subtype DELAY (in ms).
*
* We use this when we've received new data packets. If those packets aren't
* all consumed within this time we will send a DELAY ACK if an ACK was not
* requested to let the sender know it doesn't need to resend.
*/
unsigned int rxrpc_soft_ack_delay = 1 * HZ;
unsigned int rxrpc_soft_ack_delay = 1 * 1000;
/*
* How long to wait before scheduling an ACK with subtype IDLE (in jiffies).
* How long to wait before scheduling an ACK with subtype IDLE (in ms).
*
* We use this when we've consumed some previously soft-ACK'd packets when
* further packets aren't immediately received to decide when to send an IDLE
* ACK let the other end know that it can free up its Tx buffer space.
*/
unsigned int rxrpc_idle_ack_delay = 0.5 * HZ;
unsigned int rxrpc_idle_ack_delay = 0.5 * 1000;
/*
* Receive window size in packets. This indicates the maximum number of

View File

@ -149,13 +149,13 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
_debug("need instant resend %d", ret);
rxrpc_instant_resend(call, ix);
} else {
unsigned long resend_at;
ktime_t now = ktime_get_real(), resend_at;
resend_at = jiffies + msecs_to_jiffies(rxrpc_resend_timeout);
resend_at = ktime_add_ms(now, rxrpc_resend_timeout);
if (time_before(resend_at, call->resend_at)) {
if (ktime_before(resend_at, call->resend_at)) {
call->resend_at = resend_at;
rxrpc_set_timer(call, rxrpc_timer_set_for_send);
rxrpc_set_timer(call, rxrpc_timer_set_for_send, now);
}
}

View File

@ -35,7 +35,7 @@ static struct ctl_table rxrpc_sysctl_table[] = {
.data = &rxrpc_requested_ack_delay,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_ms_jiffies,
.proc_handler = proc_dointvec,
.extra1 = (void *)&zero,
},
{
@ -43,7 +43,7 @@ static struct ctl_table rxrpc_sysctl_table[] = {
.data = &rxrpc_soft_ack_delay,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_ms_jiffies,
.proc_handler = proc_dointvec,
.extra1 = (void *)&one,
},
{
@ -51,7 +51,7 @@ static struct ctl_table rxrpc_sysctl_table[] = {
.data = &rxrpc_idle_ack_delay,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_ms_jiffies,
.proc_handler = proc_dointvec,
.extra1 = (void *)&one,
},
{
@ -85,7 +85,7 @@ static struct ctl_table rxrpc_sysctl_table[] = {
.data = &rxrpc_max_call_lifetime,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
.proc_handler = proc_dointvec,
.extra1 = (void *)&one,
},