[TIMEWAIT]: Move inet_timewait_death_row routines to net/ipv4/inet_timewait_sock.c
Also export the ones that will be used in the next changeset, when
DCCP uses this infrastructure.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 81b9a52..dc08523 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -35,12 +35,6 @@
#define SYNC_INIT 1
#endif
-/* New-style handling of TIME_WAIT sockets. */
-
-static void inet_twdr_hangman(unsigned long data);
-static void inet_twdr_twkill_work(void *data);
-static void inet_twdr_twcal_tick(unsigned long data);
-
int sysctl_tcp_syncookies = SYNC_INIT;
int sysctl_tcp_abort_on_overflow;
@@ -63,10 +57,6 @@
EXPORT_SYMBOL_GPL(tcp_death_row);
-static void inet_twsk_schedule(struct inet_timewait_sock *tw,
- struct inet_timewait_death_row *twdr,
- const int timeo);
-
static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
{
if (seq == s_win)
@@ -173,9 +163,11 @@
if (tw->tw_family == AF_INET &&
tcp_death_row.sysctl_tw_recycle && tcptw->tw_ts_recent_stamp &&
tcp_v4_tw_remember_stamp(tw))
- inet_twsk_schedule(tw, &tcp_death_row, tw->tw_timeout);
+ inet_twsk_schedule(tw, &tcp_death_row, tw->tw_timeout,
+ TCP_TIMEWAIT_LEN);
else
- inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
return TCP_TW_ACK;
}
@@ -213,7 +205,8 @@
return TCP_TW_SUCCESS;
}
}
- inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
if (tmp_opt.saw_tstamp) {
tcptw->tw_ts_recent = tmp_opt.rcv_tsval;
@@ -263,7 +256,8 @@
* Do not reschedule in the last case.
*/
if (paws_reject || th->ack)
- inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN);
+ inet_twsk_schedule(tw, &tcp_death_row, TCP_TIMEWAIT_LEN,
+ TCP_TIMEWAIT_LEN);
/* Send ACK. Note, we do not put the bucket,
* it will be released by caller.
@@ -326,7 +320,8 @@
timeo = TCP_TIMEWAIT_LEN;
}
- inet_twsk_schedule(tw, &tcp_death_row, timeo);
+ inet_twsk_schedule(tw, &tcp_death_row, timeo,
+ TCP_TIMEWAIT_LEN);
inet_twsk_put(tw);
} else {
/* Sorry, if we're out of memory, just CLOSE this
@@ -341,261 +336,6 @@
tcp_done(sk);
}
-/* Returns non-zero if quota exceeded. */
-static int inet_twdr_do_twkill_work(struct inet_timewait_death_row *twdr,
- const int slot)
-{
- struct inet_timewait_sock *tw;
- struct hlist_node *node;
- unsigned int killed;
- int ret;
-
- /* NOTE: compare this to previous version where lock
- * was released after detaching chain. It was racy,
- * because tw buckets are scheduled in not serialized context
- * in 2.3 (with netfilter), and with softnet it is common, because
- * soft irqs are not sequenced.
- */
- killed = 0;
- ret = 0;
-rescan:
- inet_twsk_for_each_inmate(tw, node, &twdr->cells[slot]) {
- __inet_twsk_del_dead_node(tw);
- spin_unlock(&twdr->death_lock);
- __inet_twsk_kill(tw, twdr->hashinfo);
- inet_twsk_put(tw);
- killed++;
- spin_lock(&twdr->death_lock);
- if (killed > INET_TWDR_TWKILL_QUOTA) {
- ret = 1;
- break;
- }
-
- /* While we dropped twdr->death_lock, another cpu may have
- * killed off the next TW bucket in the list, therefore
- * do a fresh re-read of the hlist head node with the
- * lock reacquired. We still use the hlist traversal
- * macro in order to get the prefetches.
- */
- goto rescan;
- }
-
- twdr->tw_count -= killed;
- NET_ADD_STATS_BH(LINUX_MIB_TIMEWAITED, killed);
-
- return ret;
-}
-
-static void inet_twdr_hangman(unsigned long data)
-{
- struct inet_timewait_death_row *twdr;
- int unsigned need_timer;
-
- twdr = (struct inet_timewait_death_row *)data;
- spin_lock(&twdr->death_lock);
-
- if (twdr->tw_count == 0)
- goto out;
-
- need_timer = 0;
- if (inet_twdr_do_twkill_work(twdr, twdr->slot)) {
- twdr->thread_slots |= (1 << twdr->slot);
- mb();
- schedule_work(&twdr->twkill_work);
- need_timer = 1;
- } else {
- /* We purged the entire slot, anything left? */
- if (twdr->tw_count)
- need_timer = 1;
- }
- twdr->slot = ((twdr->slot + 1) & (INET_TWDR_TWKILL_SLOTS - 1));
- if (need_timer)
- mod_timer(&twdr->tw_timer, jiffies + twdr->period);
-out:
- spin_unlock(&twdr->death_lock);
-}
-
-extern void twkill_slots_invalid(void);
-
-static void inet_twdr_twkill_work(void *data)
-{
- struct inet_timewait_death_row *twdr = data;
- int i;
-
- if ((INET_TWDR_TWKILL_SLOTS - 1) > (sizeof(twdr->thread_slots) * 8))
- twkill_slots_invalid();
-
- while (twdr->thread_slots) {
- spin_lock_bh(&twdr->death_lock);
- for (i = 0; i < INET_TWDR_TWKILL_SLOTS; i++) {
- if (!(twdr->thread_slots & (1 << i)))
- continue;
-
- while (inet_twdr_do_twkill_work(twdr, i) != 0) {
- if (need_resched()) {
- spin_unlock_bh(&twdr->death_lock);
- schedule();
- spin_lock_bh(&twdr->death_lock);
- }
- }
-
- twdr->thread_slots &= ~(1 << i);
- }
- spin_unlock_bh(&twdr->death_lock);
- }
-}
-
-/* These are always called from BH context. See callers in
- * tcp_input.c to verify this.
- */
-
-/* This is for handling early-kills of TIME_WAIT sockets. */
-void inet_twsk_deschedule(struct inet_timewait_sock *tw,
- struct inet_timewait_death_row *twdr)
-{
- spin_lock(&twdr->death_lock);
- if (inet_twsk_del_dead_node(tw)) {
- inet_twsk_put(tw);
- if (--twdr->tw_count == 0)
- del_timer(&twdr->tw_timer);
- }
- spin_unlock(&twdr->death_lock);
- __inet_twsk_kill(tw, twdr->hashinfo);
-}
-
-static void inet_twsk_schedule(struct inet_timewait_sock *tw,
- struct inet_timewait_death_row *twdr,
- const int timeo)
-{
- struct hlist_head *list;
- int slot;
-
- /* timeout := RTO * 3.5
- *
- * 3.5 = 1+2+0.5 to wait for two retransmits.
- *
- * RATIONALE: if FIN arrived and we entered TIME-WAIT state,
- * our ACK acking that FIN can be lost. If N subsequent retransmitted
- * FINs (or previous seqments) are lost (probability of such event
- * is p^(N+1), where p is probability to lose single packet and
- * time to detect the loss is about RTO*(2^N - 1) with exponential
- * backoff). Normal timewait length is calculated so, that we
- * waited at least for one retransmitted FIN (maximal RTO is 120sec).
- * [ BTW Linux. following BSD, violates this requirement waiting
- * only for 60sec, we should wait at least for 240 secs.
- * Well, 240 consumes too much of resources 8)
- * ]
- * This interval is not reduced to catch old duplicate and
- * responces to our wandering segments living for two MSLs.
- * However, if we use PAWS to detect
- * old duplicates, we can reduce the interval to bounds required
- * by RTO, rather than MSL. So, if peer understands PAWS, we
- * kill tw bucket after 3.5*RTO (it is important that this number
- * is greater than TS tick!) and detect old duplicates with help
- * of PAWS.
- */
- slot = (timeo + (1 << INET_TWDR_RECYCLE_TICK) - 1) >> INET_TWDR_RECYCLE_TICK;
-
- spin_lock(&twdr->death_lock);
-
- /* Unlink it, if it was scheduled */
- if (inet_twsk_del_dead_node(tw))
- twdr->tw_count--;
- else
- atomic_inc(&tw->tw_refcnt);
-
- if (slot >= INET_TWDR_RECYCLE_SLOTS) {
- /* Schedule to slow timer */
- if (timeo >= TCP_TIMEWAIT_LEN) {
- slot = INET_TWDR_TWKILL_SLOTS - 1;
- } else {
- slot = (timeo + twdr->period - 1) / twdr->period;
- if (slot >= INET_TWDR_TWKILL_SLOTS)
- slot = INET_TWDR_TWKILL_SLOTS - 1;
- }
- tw->tw_ttd = jiffies + timeo;
- slot = (twdr->slot + slot) & (INET_TWDR_TWKILL_SLOTS - 1);
- list = &twdr->cells[slot];
- } else {
- tw->tw_ttd = jiffies + (slot << INET_TWDR_RECYCLE_TICK);
-
- if (twdr->twcal_hand < 0) {
- twdr->twcal_hand = 0;
- twdr->twcal_jiffie = jiffies;
- twdr->twcal_timer.expires = twdr->twcal_jiffie +
- (slot << INET_TWDR_RECYCLE_TICK);
- add_timer(&twdr->twcal_timer);
- } else {
- if (time_after(twdr->twcal_timer.expires,
- jiffies + (slot << INET_TWDR_RECYCLE_TICK)))
- mod_timer(&twdr->twcal_timer,
- jiffies + (slot << INET_TWDR_RECYCLE_TICK));
- slot = (twdr->twcal_hand + slot) & (INET_TWDR_RECYCLE_SLOTS - 1);
- }
- list = &twdr->twcal_row[slot];
- }
-
- hlist_add_head(&tw->tw_death_node, list);
-
- if (twdr->tw_count++ == 0)
- mod_timer(&twdr->tw_timer, jiffies + twdr->period);
- spin_unlock(&twdr->death_lock);
-}
-
-void inet_twdr_twcal_tick(unsigned long data)
-{
- struct inet_timewait_death_row *twdr;
- int n, slot;
- unsigned long j;
- unsigned long now = jiffies;
- int killed = 0;
- int adv = 0;
-
- twdr = (struct inet_timewait_death_row *)data;
-
- spin_lock(&twdr->death_lock);
- if (twdr->twcal_hand < 0)
- goto out;
-
- slot = twdr->twcal_hand;
- j = twdr->twcal_jiffie;
-
- for (n = 0; n < INET_TWDR_RECYCLE_SLOTS; n++) {
- if (time_before_eq(j, now)) {
- struct hlist_node *node, *safe;
- struct inet_timewait_sock *tw;
-
- inet_twsk_for_each_inmate_safe(tw, node, safe,
- &twdr->twcal_row[slot]) {
- __inet_twsk_del_dead_node(tw);
- __inet_twsk_kill(tw, twdr->hashinfo);
- inet_twsk_put(tw);
- killed++;
- }
- } else {
- if (!adv) {
- adv = 1;
- twdr->twcal_jiffie = j;
- twdr->twcal_hand = slot;
- }
-
- if (!hlist_empty(&twdr->twcal_row[slot])) {
- mod_timer(&twdr->twcal_timer, j);
- goto out;
- }
- }
- j += 1 << INET_TWDR_RECYCLE_TICK;
- slot = (slot + 1) & (INET_TWDR_RECYCLE_SLOTS - 1);
- }
- twdr->twcal_hand = -1;
-
-out:
- if ((twdr->tw_count -= killed) == 0)
- del_timer(&twdr->tw_timer);
- NET_ADD_STATS_BH(LINUX_MIB_TIMEWAITKILLED, killed);
- spin_unlock(&twdr->death_lock);
-}
-
/* This is not only more efficient than what we used to do, it eliminates
* a lot of code duplication between IPv4/IPv6 SYN recv processing. -DaveM
*
@@ -933,4 +673,3 @@
EXPORT_SYMBOL(tcp_child_process);
EXPORT_SYMBOL(tcp_create_openreq_child);
EXPORT_SYMBOL(tcp_timewait_state_process);
-EXPORT_SYMBOL(inet_twsk_deschedule);