mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-03 09:00:21 +00:00
Code Issues Releases Activity

Introduce a new TCP mutex, isn_mtx, which protects the initial sequence

Browse Source 
number state, rather than re-using pcbinfo.  This introduces some
additional mutex operations during isn query, but avoids hitting the TCP
pcbinfo lock out of yet another frequently firing TCP timer.

MFC after:	3 months
This commit is contained in:
Robert Watson 2006-04-22 19:23:24 +00:00
parent 602cc7f12b
commit 4c0e8f41f6
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=157967
2 changed files with 12 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sys/netinet/tcp_subr.c
View File

@ -244,6 +244,7 @@ struct tcpcb_mem {
static uma_zone_t tcpcb_zone;
static uma_zone_t tcptw_zone;
struct callout isn_callout;
static struct mtx isn_mtx;
/*
* TCP initialization.
@ -313,6 +314,7 @@ tcp_init(void)
syncache_init();
tcp_hc_init();
tcp_reass_init();
mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF);
callout_init(&isn_callout, CALLOUT_MPSAFE);
tcp_isn_tick(NULL);
EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
@ -1392,9 +1394,9 @@ tcp_new_isn(struct tcpcb *tp)
u_int32_t md5_buffer[4];
tcp_seq new_isn;
INP_INFO_WLOCK_ASSERT(&tcbinfo);
INP_LOCK_ASSERT(tp->t_inpcb);
mtx_lock(&isn_mtx);
/* Seed if this is the first use, reseed if requested. */
if ((isn_last_reseed == 0) || ((tcp_isn_reseed_interval > 0) &&
(((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz)
@ -1427,6 +1429,7 @@ tcp_new_isn(struct tcpcb *tp)
isn_offset += ISN_STATIC_INCREMENT +
(arc4random() & ISN_RANDOM_INCREMENT);
new_isn += isn_offset;
mtx_unlock(&isn_mtx);
return (new_isn);
}
@ -1440,7 +1443,7 @@ tcp_isn_tick(void *xtp)
{
u_int32_t projected_offset;
INP_INFO_WLOCK(&tcbinfo);
mtx_lock(&isn_mtx);
projected_offset = isn_offset_old + ISN_BYTES_PER_SECOND / 100;
if (projected_offset > isn_offset)
@ -1448,7 +1451,7 @@ tcp_isn_tick(void *xtp)
isn_offset_old = isn_offset;
callout_reset(&isn_callout, hz/100, tcp_isn_tick, NULL);
INP_INFO_WUNLOCK(&tcbinfo);
mtx_unlock(&isn_mtx);
}
/*

9
sys/netinet/tcp_timewait.c
View File

@ -244,6 +244,7 @@ struct tcpcb_mem {
static uma_zone_t tcpcb_zone;
static uma_zone_t tcptw_zone;
struct callout isn_callout;
static struct mtx isn_mtx;
/*
* TCP initialization.
@ -313,6 +314,7 @@ tcp_init(void)
syncache_init();
tcp_hc_init();
tcp_reass_init();
mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF);
callout_init(&isn_callout, CALLOUT_MPSAFE);
tcp_isn_tick(NULL);
EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
@ -1392,9 +1394,9 @@ tcp_new_isn(struct tcpcb *tp)
u_int32_t md5_buffer[4];
tcp_seq new_isn;
INP_INFO_WLOCK_ASSERT(&tcbinfo);
INP_LOCK_ASSERT(tp->t_inpcb);
mtx_lock(&isn_mtx);
/* Seed if this is the first use, reseed if requested. */
if ((isn_last_reseed == 0) || ((tcp_isn_reseed_interval > 0) &&
(((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz)
@ -1427,6 +1429,7 @@ tcp_new_isn(struct tcpcb *tp)
isn_offset += ISN_STATIC_INCREMENT +
(arc4random() & ISN_RANDOM_INCREMENT);
new_isn += isn_offset;
mtx_unlock(&isn_mtx);
return (new_isn);
}
@ -1440,7 +1443,7 @@ tcp_isn_tick(void *xtp)
{
u_int32_t projected_offset;
INP_INFO_WLOCK(&tcbinfo);
mtx_lock(&isn_mtx);
projected_offset = isn_offset_old + ISN_BYTES_PER_SECOND / 100;
if (projected_offset > isn_offset)
@ -1448,7 +1451,7 @@ tcp_isn_tick(void *xtp)
isn_offset_old = isn_offset;
callout_reset(&isn_callout, hz/100, tcp_isn_tick, NULL);
INP_INFO_WUNLOCK(&tcbinfo);
mtx_unlock(&isn_mtx);
}
/*